gears

Articles About gears

Articles are sorted by RELEVANCE. Sort by Date.

1 Dynamic Behavior of Planetary Gears (June 2020)

In planetary gear systems of high power density and high gear ratio, helical gears create undesirable tilting moments on the planet gears; therefore, spur gears are still preferred for planetary gears -- a special challenge with respect to noise. Specifically, the different behavior of planetary gears with sequential and symmetric gear mesh is explained in this paper.

2 Rating of Asymmetric Tooth Gears (April 2016)

Asymmetric tooth gears and their rating are not described by existing gear design standards. Presented is a rating approach for asymmetric tooth gears by their bending and contact stress levels, in comparison with symmetric tooth gears, whose rating are defined by standards. This approach applies finite element analysis (FEA) for bending stress definition and the Hertzian equation for contact stress definition. It defines equivalency factors for practical asymmetric tooth gear design and rating. This paper illustrates the rating of asymmetric tooth gears with numerical examples.

3 Efficiency and Heat Balance Calculation of Worm Gears (December 2020)

If torque conversion with high gear ratio, compact installation space and 90-degree axis-crossing angle is needed, often worm gears are used. Due to their high power density and sliding speeds within the tooth contact, frictional heat and thermal stresses are higher compared to helical, bevel and hypoid gears, and thus the thermal load capacity of worm gears is lower.

4 Precision Plastic Gears (Fall 2007)

Some gear geometries are more practical to produce than others. Since choices made early in the design process aff ect the ease and cost of fabrication, those who design gears would do well to consider molding and how molders operate, especially when they create precision gears.

5 Load Capacity and Efficiency of Grease-Lubricated Worm Gears (September 2014)

Varying installation requirements for worm gears, as, for example, when used in modular gear systems, can necessitate grease lubrication - especially when adequate sealing for oil lubrication would be too complex. Such worm gears are being increasingly used in outside applications such as solar power plants and slew drives. While knowledge about the operating conditions is often appropriate, the basic understanding for load capacity and efficiency under grease lubrication is quite poor. Investigations done at FZG and sponsored by FVA/AiF are shown here to give an impression of the basic factors of load capacity and efficiency. The results of the investigation indicate a satisfying quality of calculations on heat, load capacity and efficiency based on characteristic parameters of the base oil with only slight modifications to the methodology known from DIN 3996 or ISO TR 14521.

6 Evolution of Worm Gear Standards and their Consequences on Load Capacity Calculation Approach (September 2014)

Beginning with a brief summary and update of the latest advances in the calculation methods for worm gears, the author then presents the detailed approach to worm gear geometry found in the revised ISO TR 10828. With that information, and by presenting examples, these new methods are explained, as are their possibilities for addressing the geometrical particularities of worm gears and their impact upon the behavior and load capacity of a gearset under working conditions based on ISO TR 14521 — Methods B and C. The author also highlights the new possibilities offered on that basis for the further evolution of load capacity calculation of a worm gearset based on load and contact pressure distribution.

7 Powder Metal Gear Technology: A Review of the State of the Art (March 2016)

During the past 10 years, the PM industry has put a lot of focus on how to make powder metal gears for automotive transmissions a reality. To reach this goal, several hurdles had to be overcome, such as fatigue data generation on gears, verification of calculation methods, production technology, materials development, heat treatment recipes, design development, and cost studies. All of these advancements will be discussed, and a number of vehicles with powder metal gears in their transmissions will be presented. How the transmissions have been redesigned in order to achieve the required stress levels while minimizing weight and inertia, thus increasing efficiency, will also be discussed.

8 3-D Printing and Plastic Gears (March 2015)

Regarding 3-D printing of gears and machine tools, etc. — does plastic gearing have a future in 3-D printing/additive manufacturing?

9 Design Investigations and Indications for Acoustical Optimized Gear Meshes Using Plastic Gears (February 2019)

When it comes to a steel-gear mesh, there are several common standards and design rules on how to reduce noise emissions in the mesh. But if plastic gears are involved, this is no longer the case. The topic of this presentation is to highlight some of the differences between metal-and-plastic gear meshes, i.e. which design strategies can be stated as valid for metal as well as plastic and which are not?

10 FEM Analysis of the Load Distribution over the Face Width of Helical Gear Pairs Considering Deviations, Misalignments and Deformations (August 2020)

The load carrying capacity of spur gears may be calculated by ISO 6336 using influence factors. The face load factor considers the impact of the non-uniform load distribution over the face width. Even if the gears had perfect geometry, the load would not distribute uniformly along the contact lines. The face load factor depends on deformations of all parts of the containing gearbox and mainly of the teeth, gears and shafts as well as on manufacturing and assembly deviations.

11 Driving Gears 2019 (September 2019)

Efficiency, power-loss reduction and enhanced performance are just a few examples of what the PT community wants from their gears and gear drives in 2019. Some companies are doubling down on service and assembly capabilities while other others are integrating components in an effort to increase flexibility and control.

12 Lubrication of Plastic Worm Gears (August 2019)

In the selection of lubricating greases for plastic worm gears, the user needs to know the influence of each grease constituent on the tribological performance in order to choose the appropriate lubricant. In this work, the effect of NLGI class, viscosity, base oil and thickener type are investigated separately regarding the efficiency and temperature close to the tribocontact. With the help of this contribution the user understands the effect of each parameter and learns about the potentially reachable efficiency and temperature ranges.

13 Net-Forged Bevel and Transmission Gears (August 2014)

What are the applications for net-forged gears. Are they used outside automotive differentials?

14 Efficient Layout Process of Cylindrical Gears with Manufacturing Constraints (March 2019)

Cylindrical gear design can be divided into three steps. In the first step, rough gear pair dimensions such as center distance and face width are being estimated. Center distance and face width are directly linked to the available space (housing dimensions) and influence the overall size, weight and cost of the gears.

15 Product Focus: Gears and Gear Drives (February 2011)

In this special news section, the editors of Power Transmission Engineering have gathered the latest product news and information from the gears and gear drives sector.

16 Gears and Gear Drives Product Focus (February 2013)

Our product focus includes the latest technology in gears and gear drives from the leading manufacturers.

17 Up in the Air - Aerospace Gears (April 2013)

Volatile aerospace market keeps gear manufacturers guessing.

18 Gear Expo 2015: Gears Galore! (September 2015)

You may well have already read the following Gear Expo description on the AGMA Website.

19 Effects of Contact Ratios on Mesh Stiffness of Helical Gears for Lower Noise Design (August 2015)

In this paper, the influences of various gear parameters on the mesh stiffness are systematically investigated by using the finite element method. The comprehensive analysis shows that contact ratios are the key factors affecting the fluctuation value of mesh stiffness.

20 Vibration and Operational Characteristics of a Composite-Steel (Hybrid) Gear (December 2017)

Free vibration and dynamic operation testing of hybrid gears at NASA Glenn Spur Gear Fatigue Test Facility; hybrid gears are compared to their steel counterparts.

21 Engineering Showcase - Gears and Gear Drives (September 2018)

Machinists Inc. is integrating the machinery, equipment and know-how of The Gear Works-Seattle Inc.

22 3x3 Puzzle Cubes with Gears (June 2020)

Looking at a Gear Cube XXL, you can't help but think about a Rubik's Cube. Both are 3x3 puzzle cubes with brightly colored pieces. Moreover, both are sold commercially as toys.

23 Validation Approach of PM Gears for e-Drive Applications (October 2019)

Key technical drivers which can be addressed by advanced PM manufacturing technologies are, for example, the need for system downsizing in transmissions and differentials, the need for developing systems with higher power density and the strong NVH (Noise Vibration Harshness) requirements - especially for electrified transmissions or e-axle solutions.

24 Gears for Industry, Gears for Defense, Gears for Almost Anything at Gear Expo 2011 (October 2011)

What would Gear Expo be without gear manufacturers? While it is useful and indeed necessary to keep abreast of the new machinery out there that will be front-and-center at the show, it is of equal import to check out the finished product - GEARS.

25 Gear Wear Calculation and Prediction (February 2015)

Wear is a very important topic for dry running plastic gears. Over the past few years, the authors have worked closely with a number of manufacturers of plastic gears to investigate the problems of gear wear in detail. Together they have developed a calculation method that can be used to predict where and when local wear will occur on a tooth flank. Their findings have also just been published in the final version of VDI 2736.

26 Design of Plastic Microgear Teeth for Mass Production with High Manufacturing Tolerances for a Medical Device (March 2018)

Microgears for some types of medical technology need to be inexpensively mass produced. But at the same time, they need to be both precise and reliable, even though their design lifetime is relatively short. Here's how microgears were developed for blood glucose measuring devices, insulin pumps for diabetics and other very small devices.

27 A Model for Predicting Churning Losses in Planetary Gears (September 2019)

In the general context of the reduction of energy consumption and polluting emissions, gearbox efficiency has become a major issue.

28 Electric Vehicles Need Quieter Gears (October 2014)

For Mark Findlay of UK specialist driveline consultancy Drive System Design, reducing gear noise to suit the low noise levels in an electric vehicle cabin has meant throwing away the rule book.

29 Gear Lubrication: Long-Term Protection for Wind Turbines (April 2014)

The chemical and physical properties of gear oils may change, depending - more or less - upon their formulation and the environmental conditions under which they are used. This is why - after three years of use in a wind turbine - a gear oil was examined to determine if indeed changes were evident and if the protection of the gears and rolling bearings still met the same requirements as would be expected of fresh oil. Our findings revealed that the existing gear oil - as well as its ability to protect the gears and rolling bearings - had degraded very little compared to fresh oil.

30 The Applications of Bevel Gears (December 2014)

EDITORS’ NOTE: “The Applications of Bevel Gears” is the excerpted third chapter of Dr. Hermann Stadtfeld’s latest book — Gleason Bevel Gear Technology (The Gleason Works, Rochester, New York, USA; All rights reserved. 2014; ISBN 978-0-615-96492-8.), which appears here unabridged through the kind graces of Dr. Stadtfeld and Gleason Corp. Future installments will appear exclusively in Power Transmission Engineering and Gear Technology magazine over the next 12 to 18 months.

31 Gears for Hydraulic Pumps: Development and Results (March 2014)

After a brief introduction to the importance of gear pumps in internal combustion engines, as well as in the most diverse hydraulic applications, a calculation method was applied that allows for sizing with considerably higher delivery rates. Upon identifying and analyzing a traditional pump, along with two construction solutions of asymmetric gear pumps, we then compared their related performances.

32 Gear Expo is for Gear Buyers (September 2017)

Most of you who read this magazine have a close relationship with gears and gear drives. According to our surveys, 75% of you recommend, specify or buy them. It's a shame, then, that the majority of you will miss Gear Expo (Oct. 24-26 in Columbus, OH) this year.

33 Gear Design Effects on Performance of High-Speed Helical Geartrains as Used in Aerospace Drive Systems (March 2016)

The performance of high-speed helical geartrains is of particular importance for tiltrotor aircraft drive systems. These drive systems are used to provide speed reduction/torque multiplication from the gas turbine output shaft and provide the necessary offset between these parallel shafts in the aircraft. Four different design configurations have been tested in the NASA Glenn Research Center, High-Speed Helical Geartrain Test Facility. The design configurations included the current aircraft design, current design with isotropic superfinished gear surfaces, double-helical design (inward and outward pumping), increased pitch (finer teeth), and an increased helix angle. All designs were tested at multiple input shaft speeds (up to 15,000 rpm) and applied power (up to 5,000 hp). Also two lubrication, system-related, variables were tested: oil inlet temperature (160–250° F) and lubricating jet pressure (60–80 psig). Experimental data recorded from these tests included power loss of the helical system under study, the temperature increase of the lubricant from inlet to outlet of the drive system and fling-off temperatures (radially and axially). Also, all gear systems were tested with and without shrouds around the gears.

34 Determination of Load Distributions on Double Helical-Geared Planetary Gearboxes (June 2017)

Standardized calculation methods such as ISO 6336 and DIN 3990 already exist to determine the load distributions on gears inside a planetary gearbox, but by their very universal nature, these methods offer varying results depending on the gearbox design. Double helical gears, in particular, can benefit from more specific, complex algorithms to reach a maximum level of efficiency. Double helical gears interact with the rest of the gearbox differently than helical or spur gears, and thus benefit from different analytical models outside the standardized methods. The present research project describes the algorithm to determine the load distribution of planetary gearboxes with double helical gears.

35 Homogeneous Geometry Calculation of Arbitrary Tooth Shapes: Mathematical Approach and Practical Applications (February 2016)

This paper provides a mathematical framework and its implementation for calculating the tooth geometry of arbitrary gear types, based on the basic law of gear kinematics. The rack or gear geometry can be generated in two different ways: by calculating the conjugate geometry and the line of contact of a gear to the given geometric shape of a known geometry (e.g., a cutting hob), or by prescribing the surface of action of two gears in contact and calculating the correspondent flank shapes.

36 Gear Design (December 2017)

Our expert explores standard vs. optimized gears, as well as high contact ratio gearing.

37 The Latest Design Technologies For Gear Devices with Great Transmission Ratios (December 2014)

Four types of gear devices with great transmission ratios (simply called great ratio gears or GRGs) are discussed in this paper. They are strain wave gearing devices (SWGs), trochoidal gear reducers (TGRs), hypocyclic gear reducers (HGRs) and James Ferguson-type planetary drives (JFDs). The structures, advantages and basic performances of these four devices are compared. The latest design and strength analysis methods are also introduced. To conclude, the future tendencies of GRGs are predicted.

38 A New Standardizable Calculation Method to Predict the Efficiency of Worm Gear Drives (March 2018)

In this work a physically based method for the tribological investigation of worm gears is presented.

39 A Case for Large-Scale Manufacturing (October 2011)

Big components aim to revive the North American industrial market.

40 CFD Simulation of Geared Transmissions with Injection Lubrication (August 2019)

In this study, a finite volume CFD simulation model of a single-stage injection-lubricated test gearbox was applied to investigate its oil flow and no-load power loss. The results provide physically plausible information on the oil supply and its distribution.

41 Influential Criteria on the Optimization of a Gearbox, with Application to an Automatic Transmission (September 2018)

In the design of an automatic transmission gearbox, the variation of one parameter can result in different system performances due to the strong interdependencies among all components. For given transmission ratios, component lifetimes and safeties, or space restrictions, improvements in efficiency, noise, and weight can be achieved.

42 Analyzing Contact Patterns for UAV Helicopter Transmissions (August 2019)

In a research project at the Vienna University of Technology, the KISSsoft design software was used to check a new drivetrain concept and the micro-geometry of the bevel gear stage for a UAV (unmanned aerial vehicle).

43 Mold Machining Center Maintains Accuracy (June 2008)

Entrust enlists Advanced Machine & Engineering for 7-axis, 2-spindle performance.

44 MPT Expo 2019 Booth Previews (September 2019)

MPT Expo takes place October 15-17 at TCF CENTER (formerly the Cobo Center) in Detroit. Here are booth previews of some of the exhibitors most relevant to buyers of mechanical power transmission components.

45 Industry News (December 2018)

The complete Industry News section from the December 2018 issue of Power Transmission Engineering.

46 Working in AutoCAD (April 2014)

How does one draw and mesh involute gear teeth in AutoCAD?

47 Specifying a Gear - Ask the Expert (February 2014)

A reader asks what are the required parameters to properly specify a gear.

48 Comparing Data Sources for Condition Monitoring Suitability (September 2020)

Condition-based maintenance requires detailed state knowledge, often acquired by means of sensors.

49 A Little Peace of Mind (June 2020)

Condition Monitoring Technology Evolves for Gear Drives, Gearmotors and Gearboxes. Here's a look at what some leading manufacturers are offering.

50 Development of an Actuator for Ambient to Cryo Application (December 2010)

During the qualification campaign of the NIRSpec (near-infrared spectrometer) instrument mechanism, the actuator could not achieve the expected lifetime that had been extended during the development phase. The initial design could not be adapted to the requested number of revolutions during that phase. Consequently the actuator needed to be modified so that the function of the mechanism would not be endangered or, by extension, the overall function of the NIRSpec instrument. The modification included a change of the overall actuator design—internal dimensions, tolerances, materials, lubrication and assembly process—while keeping the interface to the mechanism, mass and function.

51 Considerations for Gearmaking in Wind Turbine Applications (June 2010)

A Q&A with N.K. Chinnusamy, president of Excel Gear of Roscoe, IL.

52 Total System Efficiency (February 2010)

Much of the industrial energy being consumed by systems is wasted through inefficiency. For this article, a system will be defined as the following components working together: electrical input power, variable frequency drives, induction motors, gearboxes and transmission elements (chains, belts, etc.).

53 Phase Management as a Strategy to Reduce Gear Whine in Idler Gear Sets (April 2020)

This work explains why some idler sets produce so much gear whine. While transmission error must be managed, there is another tool in the gear whine management toolbox.

54 Help Wanted (September 2020)

Options available for those looking for safe, online/in-person gear knowledge.

55 Wall to Wall Technology (August 2014)

With the addition of Industrial Automation North America (IANA) as well as Motion, Drive & Automation North America(MDA NA), IMTS 2014 has greatly expanded its range of manufacturing technology services. These co-located shows complement the metalworking solutions found at IMTS by bringing in key suppliers from around the world.

56 Geography Quiz (October 2019)

How well do you know your public gear art? Match wits with the Power Play travel team by trying to identify the locations of these awesome works of public art. Answers at the bottom of the page!

57 Computing Gear Sliding Losses (February 2020)

As concerns surrounding the environmental impact of fossil fuels continue to grow, so does the need to produce vehicles with higher overall efficiency. The importance of enhanced vehicles has spurred drivetrain component manufacturers to study every aspect of efficiency loss in their products. The gearbox is a key contributor to the overall drivetrain efficiency.

58 MPT Expo Showstoppers (September 2019)

These exhibitors want you to know they're making a splash at MPT Expo 2019.

59 How to Spec a Mill Gear (February 2014)

This paper outlines the design considerations that go into construction of a drive system in order to explain the importance of specific data, why it is required, and where design freedom is necessary. Apart from loads and speeds, interface dimensions and site specific conditions are also needed. Deciding up front which gear rating practice to select can affect the torque capacity of the drive train by ~15%.

60 Dont Tap the Glass (June 2015)

Behind a thick sheet of unblemished glass that stretches from wall-to-wall, ceilingto- floor at Delta Gear, just south of a shop lined with ultramodern grinding machines whirring away, is Scott Sakuta’s aquarium.

61 Calculation of the Efficiency of Worm Gear Drives (June 2015)

This paper presents a physically grounded calculation method to determine the efficiency of worm gear drives. This computation is based on the Institute of Machine Elements, Gears, and Transmissions (MEGT) tribological simulation, which can determine the local tooth friction coefficients (Ref. 1). With this knowledge other power losses such as the bearings, oil churnings and seals power losses can also be calculated.

62 Mapping the World of Manufacturing (August 2018)

After decades of iteration, you might think manufacturing software suites are running out of new modules to add, but improving hardware is opening up new avenues for them to explore.

63 Crowning Spur Teeth - Ask the Expert - December 2013 PTE (December 2013)

When designing spur teeth, is there a formula/guideline/design guide for determining the amount of crowning?

64 Product News (April 2015)

Latest Products

65 How to Get the Most Realistic Efficiency Calculation for Gearboxes (April 2015)

In recent years the estimation of gearbox power loss is attracting more interest — especially in the wind turbine and automotive gearbox industry — but also in industrial gearboxes where heat dissipation is a consideration as well. As new transmissions concepts are being researched to meet both ecological and commercial demands, a quick and reliable estimation of overall efficiency becomes inevitable in designing the optimal gearbox.

66 The 5 Golden Rules of Gear Buying (February 2015)

Let’s be clear about something up front here: Delta Gear does not make parts for lawnmowers. This is a fairly flippant point that falls under the timeless, clichéd designation of “goes without saying.” Yet, not all that long ago,Tony Werschky had to say it.

67 How to Design a Spur-Crown Gear Set (October 2013)

When designing a spur-crown pair, is there a formula, guideline or design guide for adapting the spur teeth for the radial angle of the teeth in the crown?

68 There Is a Great Future in Plastics (April 2015)

The first thing you see when you walk into Winzeler Gear is a pretty face. No, scratch that — the face is beautiful. Streamlined with chiseled cheek bones, delicate yet bold and strong, a half dozen photos of the feminine face line the building’s entranceway, enclosed tastefully in simple black picture frames, beckoning you to come further in with its pleasant warmth, repelling you to turn and leave with its foreign presence in such a location.

69 Diametral Pitch Calculation (April 2015)

Circular pitch gives me the size of the teeth in my mind, but diametral pitch does not. What is the purpose of the diametral pitch concept? Does it merely avoid pi in calculation?

70 Engineering Showcase 2016 (March 2016)

One of our goals at Power Transmission Engineering is to help you understand, identify and select the best technology for your mechanical power transmission or motion control applications. With every project, you have to decide which components to use, and which suppliers, based on functionality, quality and price. We aim to help you make those decisions informed by providing the latest information on current technology, especially when it comes to mechanical components.

71 Is Splash Lubrication Compatible with Efficient Gear Units for High-Speed Applications (October 2015)

A thermo-mechanical model of a splash lubricated one-stage gear unit is presented. This system corresponds to a first step towards the design of a hybrid vehicle gearbox that can operate up to 40,000 rpm on its primary shaft. The numerical model is based on the thermal network method and takes into account power losses due to teeth friction, rolling-elements bearings and oil churning. Some calculations underline that oil churning causes a high amount of power loss. A simple method to reduce this source of power losses is presented, and its influence on the gear unit efficiency and its thermal capacity is computed.

72 Product News (December 2017)

The complete Product News section from the December 2017 issue of Power Transmission Engineering, featuring the latest from SKF, R+W, Brecoflex, Nexen, Güdel, Renold Gears, Hansford Sensors, Ogura Industrial, Igus, Destaco, Röhm and Iwis.

73 Applying Open Gear Lubricants (February 2012)

When selecting an open gear lubricant for use in a particular application, the method of application used must be considered.

74 The Development of Worm Drives (February 2018)

A worm drive is a geared power transmission device in which a worm meshes with a worm gear to transmit power between two non-intersecting shafts that are oriented at a right angle. The worm drive has been an active and challenging topic of technological study since Leonardo da Vinci (1452-1519).

75 Gear Design Software, Engineer Beware (February 2014)

When software goes bad, what do we call it? System failure? Human failure? A virus? A number of words will work. How about this? Glitch. It has that onomatopoeic quality that fairly screams, Downtime! And with good reason -- software-generated miscalculations can have very expensive -- if not perilous -- repercussions.

76 Gear Span Measurements (August 2017)

A reader is looking for the best reference materials with formulas for gear measurements over pins.

77 Testing of Alternative Spiral Bevel and Hypoid Gear Theory (August 2014)

Following is a presentation of a gear design based upon a theoretically perfect gear technology, for which an overview is offered for consideration. What follows is a report on the design's testing and subsequent manufacture of a hypoid gear pair for a 1999 Ford Mustang.

78 Industry News (December 2013)

The complete Industry News section from the December 2013 issue of Power Transmission Engineering.

79 Harvesting Knowledge (August 2017)

The season of harvest is upon us. And I don't mean crops, although here in the U.S. Midwest, there's plenty of that going on, too. No, what I mean is knowledge, because in addition to being the end of the growing season, the transition between summer and fall also marks the busiest time of year when it comes to trade shows, conferences and industry gatherings.

80 Worm Gear Cutting (August 2016)

I have a fairly straightforward question about a worm gear segment. But as of yet, I haven’t gotten a straight answer from any of the gear job shops I’ve approached about this job. Is there a "traditional" gear cutting method that can produce a ~180 degree enveloping worm gear segment when a feature on the back of the part will interfere with a complete rotation of the part? Or am I left with only the option of 4- or 5-axis surfacing with a CNC mill? I have presented this part to several well-known gear shops in the U.S. without a straight answer on how the part can be made. Any help you could offer would be appreciated.

81 Industry News (December 2016)

News from around the industry.

82 Gear Materials (April 2017)

A reader wants to know how to figure out the fatigues strength, tooth root tension and other technical values of new, high-performance gear materials.

83 Mutiple Gearset-Type Calculation Software (September 2015)

Is there a gear software package out there that will calculate the design of spur, helical, worm, and planetary gearsets? Also, we would like a program that calculates stresses and material selection. Finally, we would like to have the program calculate bearings loads, too. Thank you for your help.

84 Frictionless, Magnetic Gears and Couplings Gain Traction (February 2010)

The Magnetic Gearing and Turbine Corp. (MGT), founded by Australian inventor Andrew French in 2000, manufactures injection molded gears and couplings based entirely on magnetic technology. The repulsive magnetic forces are used to transmit power without losing any energy, and drive shafts rotate completely independently of each other.

85 Engineering Showcase - Gears and Gear Drives (September 2019)

See our special advertising section focused on gears and gear drives from the September 2019 issue of Power Transmission Engineering.

86 Mathematical Modeling for the Design of Spiroid, Helical, Spiral Bevel and Worm Gears (April 2015)

Spiroid and worm gears have superior advantages for hightorque and miniaturization applications. And for this reason they are particularly preferred in aerospace, robotic and medical applications. They are typically manufactured by hobbing technology, a process with a typical overall lead time of 4 to 14 weeks.

87 Determining Diametral Pitch, Center Distance (October 2016)

I need help determining the diametral pitch needed to achieve the closest center-to-center distance for 2 spur gears. The 1st gear is a 34-tooth and the 2nd gear is a 28-tooth. The center-to-center distance between the gears needs to be as close to 2 1/8" as possible.

88 Optimization of Power Density by Local Gear Failure Modeling (March 2019)

Power density is a key factor in gear design. Increasing the power density enables engineers to use smaller gears for their applications which lead to smaller and lighter gear boxes. The benefit for example for the automotive industry is less moving load in the vehicles and therefor a reduction of fuel consumption and subsequently a reduction of CO2 emission. The limiting factor for the increase in power density of gears is the material strength in regard to the critical failure mode.

89 Low-Efficiency Motors and Gears Still Prevalent (October 2014)

Electric motor-driven systems are the single largest enduser of electricity, accounting for over 40% of global consumption according to the International Energy Agency.

90 Experimental Determination of Oil Rheology Parameters to be Implemented in Power Loss Predictions of Gears and Rolling Element Bearings (April 2019)

Rheology models express the way tribological conditions translate to shear stress of the lubricant and friction force on the interacting surfaces. Due to the complexity of the lubricant rheology, the friction coefficient is usually obtained experimentally either under the same operating conditions or by curve fitting in a properly chosen friction map. The current study aims at determining the rheological parameters of a lubricant based on friction measurements carried out on a commercial, readily available ball-on-disc machine.

91 Bearings and Motors and Gears (September 2020)

Oh my. It's been another busy month here at Power Transmission Engineering, and we have another full issue for you. This time around we have a focus on bearings, with plenty of great examples of applications and technology from the world's leading manufacturers. Of course, bearings are essential to power transmission and a core subject we cover every issue. But when it's the focus, we like to attack the subject from multiple different angles.

92 Gears, Fluid Power and Electric (February 2019)

The American Gear Manufacturers Association has evolved its trade show. What was formerly Gear Expo is now the Motion + Power Technology Expo (MPT Expo), an event intended to represent the entire motion and power transmission supply chain. As part of the expansion of the show’s scope, AGMA has partnered with the NFPA (National Fluid Power Association) to include a fluid power pavilion and additional educational sessions.

93 It Doesn't End Here (December 2016)

This issue, we're pleased to present our annual Buyers Guide. It's our comprehensive directory of suppliers of mechanical components, including gears, bearings, motors, couplings, clutches, brakes, gear drives and more. This directory represents our best effort to give you updated information about the companies who can provide you with the components you need to design, build and maintain better machinery.

94 2016 PTE Buyers Guide (December 2016)

A comprehensive directory of suppliers of gears, bearings, motors, couplings and other mechanical power transmission and motion control components.

95 He Shoots, He Scores! (April 2016)

There’s nothing quite as satisfying as scoring a goal. Here at Power Transmission Engineering, our goal is to provide you with as much relevant educational and technical material as possible, and every issue we strive to cover the subjects of power transmission and motion control from as many different angles as possible, so that no matter your job title, and no matter your industry, if gears, bearings, motors and related components are important to you, we’ve got you covered.

96 An Open-And-Shut Case: Greases for Gear Applications (September 2016)

For the lubrication of open gear drives used in different industrial applications such as cement and coal mills, rotary furnaces, or where the sealing conditions are difficult, semi-fluid greases are often used in preference to fluid oils. For girth gear applications the greases are used with a splash or spray lubrication system. The selection of such greases influences pitting lifetime and the load-carrying capacity of the gears, as well as wear behavior

97 High Gear Ratio Epicyclic Drives (June 2016)

Referencing a June 2014 Article, “High Gear Ratio Epicyclic Drives Analysis,” by Dr. Alex Kapelevich: I have designed a small compound epicyclic gearbox with common planets. Sun = 10 teeth Planet = 14 teeth Ring Gear stationary = 38 teeth Ring gear output = 41 teeth profile shifted onto a 38 tooth pitch diameter. Carriers are simply cages for the planet alignment and location. According to your article, and according to my calculations and the prototype I have built, my inputto- output ratio is a reduction of 65.6:1. I am using a ~ VG1 viscosity grease and Nylatron materials for the gears and carriers.

98 Alternative to Ni-Bearing Carburizing Steels (June 2016)

Standard carburizing steel 18CrNiMo7-6 is often used when high hardenability is required, but due to its highly fluctuating price, there has always been an incentive to develop Ni-free steel grades. The 23MnCrMo5-5-2 — or Jomasco 23mod — has been developed for this purpose. But to ensure smooth substitution within existing production lines, a number of points must be addressed: first, checking the response to carburizing treatments; and second, having similar mechanical properties with identical tooth root bending performance on gears. The latter is the purpose of this paper.

99 The Big Picture (February 2017)

When you work day-in and day-out with components like gears, bearings or electric motors, for example, it's easy to forget that those components are always part of a much bigger system.

100 Battle Bots - Victorian Edition (April 2017)

Airships, gears, robots, steam power and buzzer-beating theatrics highlight the 2017 FIRST (For Inspiration and Recognition of Science and Technology) Robotics Competition known as FIRST Steamworks.

101 The Influence of Bevel Pinion Retractability on Casing Design (March 2021)

The intuitive modeling techniques in the FVA-Workbench guarantee consistent, valid, and manufacturable gears every time.

102 Core Subjects (October 2019)

magazine. Instead of focusing on a specific industry, we focus on specific subject: namely, the mechanical power transmission components that drive many different types of machinery. So we find ourselves continuously writing about the same things: gears, bearings, motors, gear drives and so on. But this is a good thing.

103 Your Search Starts Here (December 2018)

This issue, we're pleased to present our annual Buyers Guide. It's our comprehensive directory of suppliers of mechanical components, including gears, bearings, motors, couplings, clutches, brakes, gear drives and more.

104 Engineering Showcase 2018 (March 2018)

We are pleased to present our fourth annual Engineering Showcase, a celebration of some of the leading products and companies in mechanical power transmission. In the pages that follow, you'll find examples of engineering excellence and technological know-how in the field of gears, drives, couplings, machine parts and other mechanical components.

105 Machine Elements - Shaping the Future through Continuous Evolution (February 2022)

Does Moore's Law apply to machine elements such as gears, bearings and mechanical components?

106 Leading through Crisis (April 2020)

Manufacturers are awesome. Over the past month, we've talked to a lot of manufacturers of gears, bearings, motors, gearboxes, couplings and other mechanical power transmission components. Despite the challenges brought about by the COVID-19 pandemic and the current economic crisis, they've been universally positive and remarkably confident about their current operations and ability to continue through the crisis and after.

107 Intermetallic Nickel-Titanium Alloys for Oil-Lubricated Bearing Applications (August 2009)

Nitinol 60 (60NiTi), an intermetallic nickel-titanium alloy containing 60 wt % nickel and 40 wt % titanium, is shown to be a promising material for oil-lubricated, rolling and sliding contact applications such as bearings and gears.

108 Motion, Drive and Automation at Hannover Messe 2013 (February 2013)

Power transmission and motion control companies will be on-hand during Hannover Messe 2013 to display the latest technology offerings in key product categories including roller bearings, gears, pumps, motors, transmissions, drive system components, clutches and braking systems.

109 Preventing Fretting Fatigue in Blade Dovetail Roots by Modifying Geometry of Contact Surfaces (August 2013)

Dovetails, gears and splines have been widely used in aero engines where fretting is an important failure mode due to loading variation and vibration during extended service. Failure caused by fretting fatigue becomes a prominent issue when service time continues beyond 4,000 hours. In some cases, microslip at the edge of a contact zone can reduce the life by as much as 40–60 percent.

110 Seeking Suppliers (October 2013)

Last month's Gear Expo in Indianapolis provided a great opportunity to meet potential suppliers of mechanical power transmission components -- mostly gears and gear drives, of course, but also a smattering of suppliers of bearings and motors as well.

111 Gearbox Bearing Service Life: A Matter of Mastering Many Design Parameters (April 2012)

The availability of high-strength shaft materials, in combination with bearings with high carrying capacity, allows use of slimmer shafts. However, the modulus of elasticity remains the same, so seat design for bearings and gears must be given close attention.

112 Run Like the Wind - Windpower Conference Heads to Chicago (April 2009)

Wind is the talk of the town. It has become especially relevant to the power transmission community where bearings, gears, couplings, motors and gearboxes are providing the equipment for this thriving alternative energy industry. It comes as no surprise that the Windpower 2009 Conference and Exhibition, arriving in Chicago from May 4–7, will be the largest gathering of wind energy professionals and technologies to date.

113 Gear Expo - Gear Buyers Bonanza (August 2013)

If you’re reading this magazine, there's a good chance you're somehow involved in the design, specification or purchase of gears or geared products. As such, I urge you to make plans now to attend Gear Expo in Indianapolis, September 17-19

114 Rolling-Element Bearing Analysis (June 2013)

This article describes how more sophisticated modeling techniques allow the latest software to identify design issues with bearings, shafts, gears and complicated multi-body systems.

115 Clutches: Declassified (March 2016)

In the world of PT components, the clutch gets absolutely no recognition whatsoever. There are entire magazines dedicated to gears, bearings and motors, but clutches get very little press outside of the automotive industry.

116 Influence of Gear Loads on Spline Couplings (February 2014)

Involute splines are commonly used in gearboxes to connect gears and shafts, especially when high torque is transmitted through the coupling. The load is shared among multiple teeth around the coupling circumference, resulting in higher load capacity than a conventional single key. However, the total load is not equally shared among all spline teeth, mainly because of pitch deviations resulting from the manufacturing process. The load distribution along the spline engagement length is also nonuniform because of tooth misalignments and shaft torsional effects. This paper presents an investigation of the influence of spur gear loads on the load distribution of spline teeth.

117 Top 5 Reasons To Go to Gear Expo (September 2015)

Gear Expo 2015 takes place October 20–22 in Detroit. If you haven’t already made plans to attend the show, you might be might be missing out on a great chance to learn more about gears, find new potential suppliers and network with your peers.

118 Preventing Roller Bearing Failure (December 2015)

I’m building a custom gearbox with 7075 T-6 spur gears, and I’m concerned that aluminum flakes will enter the races on the roller bearings (SKF 2307) and cause premature failure. So my question is — should I place an oil seal on the shaft first to protect the bearing — or is this an unfounded concern and I should mount the seal in the typical manner outside the bearing? Or both? Or go with a sealed bearing? I’m confused and could use your expertise, please.

119 Engineering Smart (February 2016)

Our theme for 2016 is “Engineering Smart.” Our goal as a publication is to help you engineer better systems, taking advantage of the latest in technology to create mechanical systems that last longer, save energy, cost less and increase performance. The way we do that is by bringing you the best information possible on the design and engineering of gears, gear drives, bearings, motors, couplings and related power transmission components and systems.

120 Engineering Showcase 2014 (March 2014)

We are pleased to present our first annual Engineering Showcase, a celebration of some of the leading products and companies in mechanical power transmission. In the pages that follow, you’ll find examples of engineering excellence and technological know-how in the field of gears, drives, couplings, machine parts and other mechanical components.

121 Motors and Motion Meet in St. Louis (December 2014)

The motors might be small, but the big-brain technology driving these electrical wonders was on full display at the 2014 Small Motor & Motion Association Fall Technical Conference, convened November 4-6 in St. Louis, MO. SMMA, the manufacturing trade association (120 members strong) that tends to the best interests of the electric motor and motion control industries — including manufacturers, suppliers, users, consultants and universities — played gracious host to a wide array of presenters from an equally diverse range of sources — from academia to the federal government. Like gears, motors are most everywhere, as evidenced by SMMA’s membership (consumer-, public interest-, national defense- and commercial-oriented) demographic which includes: appliance; transportation; medical equipment; office automation and computers; aerospace; and industrial automation. The association’s mission: To “serve as the principal voice of the electric motors and drives industry” and to provide a forum to “develop, collect and disseminate technical and management knowledge.”

122 Best Practices for Gearbox Assembly and Disassembly (March 2014)

In most applications, gearbox reliability is critical to the productivity of the overall plant operation. So it follows that when industry is looking at the best ways to increase efficiency, reduce downtime, and increase profitability, gearbox performance and reliability are key factors. Designing for repair, and writing effective repair procedures, can speed the service time, and provide a quality refurbishment. The best practices listed in this article are proven, effective methods used to install and remove bearings, seals, gears, couplings and shafts within a gearbox.

123 Finite Element Evaluation of Bearing Instrumentation Method (December 2014)

This paper presents an evaluation of measurements being taken on a 750 kW wind turbine gearbox being tested by the National Renewable Energy Laboratory (NREL). High-speed stage gears and bearings have been identified as critical components of the gearbox; during gearbox testing, these components were instrumented and tests were developed to evaluate loads on high-speed tapered roller bearings (TRBs). In this paper an advanced finite element-based contact modeling procedure has been applied to model the high-speed stage with the bearings fully modeled in order to evaluate strain levels. A major conclusion is that the strains of the slotted grooves are at such a level that they have acceptable signal-to-noise levels. This was verified by the results of the initial experiments presented here.

124 Gonzo Gear Design (April 2014)

Artist Tom Longtin adds completely non-circular planetary gears to his unique portfolio.

125 What Are the Limits (February 2022)

Gears and bearings can only be arranged so many ways, after all. You'd think by now that we'd have discovered every possible way to make mechanical devices as strong and efficient as possible.

126 The Packaging Perspective (September 2021)

Pack Expo Las Vegas Gears Up for In-Person Trade Show

News Items About gears

1 Worm and Spur Gears, English and Metric (May 30, 2007)
SDP/SI is an ISO 9001 manufacturer of over 13,627 spur gears, plastic gears, helical gears, bevel gears, worm gears, precision gears, int...

2 KISSsoft Adds Beveloid Gears Module (October 28, 2014)
Beveloid gears have their own new module in the KISSsoft system (module ZH1). Sizing and dimensioning of beveloid gears have been impleme...

3 KHK Announces Line of Metric Helical Gears (September 7, 2021)
KHK USA Inc., distributor of the market leading KHK brand of metric gears, announces its extensive line of helical gears, manufactured to...

4 mG miniGears Installs Furnace Loading System (June 25, 2007)
mG miniGears installed a furnace loading system in its powder metal department to avoid defects, especially for gears where small damage of the...

5 KISSsoft 03/2017 Release Allows Users to Evaluate Reliability of Gear Units, Individual Gears and Rolling Bearings (August 23, 2017)
A function in KISSsoft Release 03/2017 enables you to evaluate the reliability of gear units, individual gears and rolling bearings. ...

6 Sterling Instruments New Precision Internal Gears Selectable by Inches or Millimeters (April 30, 2006)
New precision internal gears from Sterling Instrument are available from stock in inch and metric sizes. The 20? pressure angle inch ...

7 Gleason Renames its Plastic Gears Division (June 30, 2015)
Gleason Corporation recently announced a new name for its plastic gears division: Gleason Plastic Gears. The division was formerly k...

8 Precipart to Exhibit Gears at MD&M West (December 16, 2013)
Precipart, a global supplier of custom mechanical components, gears and motion control assemblies, will be exhibiting at MD&M West, F...

9 GE Oil and Gas to Acquire Allen Gears (December 12, 2013)
Expanding its presence in the industrial gears sector, GE Oil & Gas, recently announced it has signed an agreement to acquire Allen G...

10 B&R Adds Planetary Gears to Motor Line (November 5, 2010)
B&R Industrial Automation recently announced the addition of precision planetary gears to its line of synchronous and stepper motors....

11 KISSsoft Determines Misalignment of Bevel Gears in Latest Update (October 18, 2016)
The relative position of the pinion and the ring gear is critical in determining the wear patterns of bevel gears. To determine the bevel...

12 United Stars Acquires Precision Gears (November 5, 2018)
United Stars, Inc. has announced it has acquired Precision Gears, Inc., a nearly 100-year old producer of custom gears for agriculture, f...

13 GWJ Technology Offers Enhanced Calculation of Cylindrical Gears (July 14, 2020)
GWJ Technology GmbH from Germany has updated the calculation module for cylindrical gears in its web-based software solution eAssistant.I...

14 KISSsoft Examines Plastic Gears and Tooth Form Aspects (February 11, 2021)
With injection molded plastic gears, the designer has a great degree of freedom in defining the tooth form because it is not the result o...

15 KHK Announces Line of Metric Internal Ring Gears (August 24, 2021)
KHK USA Inc., a factory owned distributor of the market leading KHK brand of metric gears, announces its extensive line of metric interna...

16 GWJ Technology Offers Detailed Online Calculation of Plastic Gears (May 26, 2020)
GWJ Technology has updated its web-based calculation software eAssistant. The calculation of plastic gears is now available.In addition t...

17 Sterling Instrument’s Anti-Backlash Gears Eliminate Marred Shafts (March 10, 2006)
A new series of 1158 anti-backlash gears manufactured by Sterling Instruments feature the Fairloc integral hub fastening system, which el...

18 KISSsoft Offers Contact Analysis (LTCA) of Asymmetric Gears (August 26, 2019)
KISSsoft now also offers contact analysis for asymmetric gears according to Langheinrich's dissertation (module ZA38). This allows, i...

19 Samputensili Master Gears Personalized to Customer or DIN Specifications (April 12, 2006)
Samputensili has introduced a range of master gears to determine work gear accuracy and setting masters to adjust checking equipment. ...

20 Ronson Gears Recognized with Enterprise Award (May 17, 2013)
Victorian gear manufacturer Ronson Gears was recently announced winner of the “Enterprise Connect Significant Achievement Award&rdq...

21 mG miniGears Acquires New Furnace (March 9, 2005)
mG miniGears acquired a high temperatures furnace that can perform at 1,300 degrees C sintering temperature. According to the company&...

22 Flowserve Introduces New Models to PT Series Worm Gears (April 13, 2005)
Flowserve Corp., a provider of fluid motion and control products and services, added two new sizes to the Flowserve Limitorque PT series ...

23 Moventas Receives Order for Mass Deliveries of Wind Turbine Gears to Acciona (January 14, 2006)
Moventas signed a supply agreement for substantial deliveries of wind turbine gearbo...

24 Helical Gears & Ground Helical Gears, Helical Gear (July 10, 2007)
QTC offers all types of Helical Gears and Ground Helical Gears. Quality Transmission Co. offers over 230 standard Helical Gear options fo...

25 mG miniGears Named One of Europe’s Fastest Growing Companies (April 15, 2006)
mG miniGears SpA of Padua announced that it has been listed No. 272 among the fastest growing European companies included in the 2006 Eur...

26 Spur Gears, Metric Gears, Gears with Internal Shafts (July 12, 2007)
These 20 degree Pressure Angle pinion shafts are made of S45C (AISI 1045) steel and feature induction hardened and ground teeth which are...

27 Renold Gears Assists Tire Manufacturer with Gearbox (February 7, 2008)
Mitas, one of the largest tire manufacturers in the Czech Republic, recently commented on the use of Renold gearboxes for their calendar ...

28 Bison Gears Adds Custom AC Motors (March 15, 2006)
Bison Gear and Engineering plans to begin manufacturing their own line of AC motors in their St. Charles, IL, facility beginning in April...

29 EFD Induction Awarded Orders for Induction Scanners to Harden Sun Gears and Output Shafts (May 26, 2015)
EFD Induction USA has recently won major orders from two American tier-one automotive suppliers.The orders involve EFD Induction ‘H...

30 Victrex Awarded Automotive Standard for Manufacture of Gears (August 9, 2019)
Victrex has achieved a new milestone for its automotive offerings. Its gear design and manufacturing facility in Grantsburg, USA, has rec...

31 Höganäs and Dontyne Gears Collaborate with Car Manufacturer (May 20, 2019)
Lighter Metal Powder components with complex designs can bring substantial cost savings for car manufacturers and system suppliers in the...

32 Thomson Offers RediMount Upgrade Option for Motors or Gears (October 25, 2018)
Thomson Industries, Inc. has launched an upgraded RediMount option, a pre-engineered, modular adapter kit for seamlessly installing motor...

33 Sumitomo Acquires Luftex Gears (January 10, 2020)
Sumitomo Machinery Corp. of America (SMA), one of the nation’s leading industrial gearbox manufacturers, is pleased to announce the...

34 Klingelnberg Offers Latest Issue of Gears Inline (November 12, 2020)
The seventh edition of “GEARS inline” is all about the big trends: Industry 4.0, automation, and electric drive concepts. New...

35 GWJ Technology Provides 3D Gears in STEP Format (April 16, 2021)
GWJ Technology GmbH has added another CAD functionality to the web-based calculation software eAssistant and the software application TBK...

36 Drivetrain Hub Launches Gears App (January 15, 2021)
Drivetrain Hub has launched its fully web-based gear software, Gears App.  Gears App is the only Software-as-a-Service (SaaS) g...

37 International Conference on Gears 2021 Extends Call for Papers Deadline (November 16, 2020)
VDI/FZG Conference on Gears 2021 has extended its call for papers deadline. Abstracts for the International Conference on Gears can be ha...

38 KISSsoft Offers 55 Plastics for Sizing Gears (September 26, 2018)
Nowadays, gear units are increasingly being made out of different types of plastic. In many cases, this class of materials is a good alte...

39 Renold Gears Displays Range of Gearing Solutions at IAAPA (November 15, 2017)
Renold displayed its range of gearing solutions for theme park rides at the IAAPA Attractions Expo in November. IAAPA is the Internationa...

40 AKGears Unveils Latest Tooth Root Fillet Optimization Software (April 14, 2015)
AKGears recently introduced the only commercially available tooth root fillet optimization software that defines the tooth root fillet pr...

41 Arrow Gear Becomes Distributor for SAMP Gears (December 9, 2014)
Arrow Gear has signed an exclusive agreement with SAMP of Bologna, Italy to market and sell their gear products in North America. Arrow G...

42 Quality Transmission Components Rebranded as QTC Metric Gears (November 10, 2014)
Designatronics, Inc., a provider of complete mechatronic engineered solutions and services to the aerospace and defense, robotics, pac...

43 Santasalo Launches Quatro+ Planetary Gears (May 18, 2015)
Santasalo recently introduced their new series of planetary gear units to the global industrial market. The new Quatro+ range offers high...

44 KISSsoft Offers Strength Analysis for Cylindrical Gears (March 24, 2016)
The strength calculation method specified in Lloyd's Register:2013 has now been implemented. This specific standard for ships is now ...

45 Renold Gears Designs Heavy-Duty Gearbox Solution for Log Washer Manufacturer (August 14, 2017)
Renold Gears has designed a heavy-duty, custom gearbox solution for a manufacturer of a special type of coarse material washers known as ...

46 GWJ Technology Offers New Calculation Modules for Cylindrical Gears (June 22, 2016)
GWJ Technology GmbH, a manufacturer of calculation software for machine elements and gearboxes, has upgraded its web-based calculation so...

47 New Redex Gears Offer Increased Versatility (November 10, 2014)
Versatility is the key issue for manufacturers of multi-axis milling machines and vertical turning lathes. The same machine must be able ...