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Results for “high torque”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1972

High torque CMG rotary actuator

A high torque rotary actuator was designed, fabricated and tested. Exacting requirements were placed on performance and physical characteristics of the actuator, particularly in the area of stiffness, backlash, torque ripple, power and size and weight. A brushless dc motor was designed utilizing rare earth magnets to meet power and weight requirements. A 26-to-1 planetary roller gear transmission was selected to best meet overall requirements. The transmission utilizes parallel gear and roller paths to minimize backlash and breakaway torque.

Source record↗
NASA NTRS1968

High-torque power wrench, a concept

High-torque power wrench is small enough to be handled by one or two men yet has sufficient torque to remove 1-1/2- to 4-inch nuts from high-pressure tanks and valves. The action can be made automatic by use of solenoid-operated valves and suitable switches.

Cox, E. F.↗
NASA NTRS1972

High torque bellows seal rotary drive

Bellows seal rotary drive device was developed which allows high torque transmission through sealed compartments. Bearing friction which would normally be carried by sealing bellows in comparable devices is absorbed by universal-gimbal joint. It can be used to transmit high torque, low speed, rotary motion through sealed barriers to prevent contamination or escape of fluids.

Diaguila, A. J.↗
NASA NTRS1976

High torque DC motor fabrication and test program

The testing of a standard iron and standard alnico permanent magnet two-phase, brushless dc spin motor for potential application to the space telescope has been concluded. The purpose of this study was to determine spin motor power losses, magnetic drag, efficiency and torque speed characteristics of a high torque dc motor. The motor was designed and built to fit an existing reaction wheel as a test vehicle and to use existing brass-board commutation and torque command electronics. The results of the tests are included in this report.

Makus, P.↗
NASA NTRS1978

High-torque open-end wrench

A wrench is described that is usable where limited access normally requires an open-end wrench, but which has substantially the high-torque capacity and small radial clearance characteristics of a closed-end wrench. The wrench includes a sleeve forming a nut-engageable socket with a gap in its side, and an adaptor forming a socket with a gap in its side, the adaptor closely surrounding the sleeve and extending across the gap in the sleeve. The sleeve and adaptor have surfaces that become fully engaged when a wrench handle is applied to the adaptor to turn it so as to tighten a nut engaged by the sleeve.

Giandomenico, A.↗
NASA NTRS1995

Special-Purpose High-Torque Permanent-Magnet Motors

Permanent-magnet brushless motors that must provide high commanded torques and satisfy unusual heat-removal requirement are developed. Intended for use as thrust-vector-control actuators in large rocket engines. Techniques and concepts used to design improved motors for special terrestrial applications. Conceptual motor design calls for use of rotor containing latest high-energy-product rare-earth permanent magnets so that motor produces required torque while drawing smallest possible currents from power supply. Torque generated by electromagnetic interaction between stator and permanent magnets in rotor when associated electronic circuits applied appropriately temporally and spatially phased currents to stator windings. Phase relationships needed to produce commanded torque computed in response to torque command and to electronically sensed angular position of rotor relative to stator.

Doane, George B., III↗
NASA NTRS1968

High-torque precision stepping drive

Stepping drive has been designed for precise incremental angular positioning of scale models of spacecraft about a horizontal axis in order to accurately measure antenna receiving and transmitting characteristics. Positioning is insured by spring-loaded, self-locking plungers.

Kaspareck, W. E.↗
NASA NTRS1986

Evaluation of a high-torque backlash-free roller actuator

The results are presented of a test program that evaluated the stiffness, accuracy, torque ripple, frictional losses, and torque holding capability of a 16:1 ratio, 430 N-m (320 ft-lb) planetary roller drive for a potential space vehicle actuator application. The drive's planet roller supporting structure and bearings were found to be the largest contributors to overall drive compliance, accounting for more than half of the total. In comparison, the traction roller contacts themselves contributed only 9 percent of the drive's compliance based on an experimentally verified stiffness model. The drive exhibited no backlash although 8 arc sec of hysteresis deflection were recorded due to microcreep within the contact under torque load. Because of these load-dependent displacements, some form of feedback control would be required for arc second positioning applications. Torque ripple tests showed the drive to be extremely smooth, actually providing some damping of input torsional oscillations. The drive also demonstrated the ability to hold static torque with drifts of 7 arc sec or less over a 24 hr period at 35 percent of full load.

Steinetz, Bruce M.↗
NASA NTRS1988

Evaluation of a high-torque backlash-free roller actuator

The results are presented of a test program that evaluated the stiffness, accuracy, torque ripple, frictional losses, and torque holding capability of a 16:1 ratio, 430 N-m (320 ft-lb) planetary roller drive for a potential space vehicle actuator application. The drive's planet roller supporting structure and bearings were found to be the largest contributors to overall drive compliance, accounting for more than half the total. In comparison, the traction roller contacts themselves contributed only 9 percent of the drive's compliance based on an experimentally verified stiffnesss model. Torque ripple tests showed the drive to be extremely smooth, actually providing some damping of input torsional oscillations. The drive also demonstrated the ability to hold static torque with drifts of 7 arc sec or less over a 24-hour period at 35 percent of full load.

Steinetz, Bruce M.↗
NASA NTRS1995

High-Torque, Lightweight, Pneumatically Driven Wrench For Small Spaces

Pneumatically driven wrench provides torque up to 3,000 lb. per ft. in small space. Designed to reach into 2.6 x 2.75 x 6 in. pocket. Weighs approximately 25 lbs. Includes reversible pneumatic motor (electric motor could be used instead) and slip clutch. Also includes device indicating total angle through which wrench turned bolt or nut. This feature used for turn-of-the-nut tightening method.

Miller, Thomas W.↗
NASA NTRS1986

Evaluation of a High-Torque Backlash-Free Roller Actuator

The results are presented herein of a test program that evaluated the stiffness, accuracy, torque ripple, frictional losses, and torque holding capability of a 16:1 ratio, 430 N-m (320 ft-lb) planetary roller drive for a potential space vehicle actuator application. The drive's planet roller supporting structure and bearings were found to be the largest contributors to overall drive compliance, accounting for more than half of the total. In comparison, the traction roller contacts themselves contributed only nine percent of the drive's compliance based on an experimentally verified stiffness model. The drive exhibited no backlash although 8 arc sec of hysteresis deflection were recorded due to microcreep within the contact under torque load. Because of these load-dependent displacements, some form of feedback control would be required for arc second positioning applications. Torque ripple tests showed the drive to be extremely smooth, actually providing some damping of input torsional oscillations. The drive also demonstrated the ability to hold static torque with drifts of 7 arc sec or less over a 24 hr period at 35 percent of full load.

Steinetz, Bruce M.↗
NASA NTRS1992

A comparison between theoretical prediction and experimental measurement of the dynamic behavior of spur gears

A comparison was made between computer model predictions of gear dynamics behavior and experimental results. The experimental data were derived from the NASA gear noise rig, which was used to record dynamic tooth loads and vibration. The experimental results were compared with predictions from the DSTO Aeronautical Research Laboratory's gear dynamics code for a matrix of 28 load speed points. At high torque the peak dynamic load predictions agree with the experimental results with an average error of 5 percent in the speed range 800 to 6000 rpm. Tooth separation (or bounce), which was observed in the experimental data for light torque, high speed conditions, was simulated by the computer model. The model was also successful in simulating the degree of load sharing between gear teeth in the multiple tooth contact region.

Rebbechi, Brian↗
NASA NTRS1993

Hubble Space Telescope EVA Power Ratchet Tool redesign

The Power Ratchet Tool (PRT) is a self contained, power-driven, 3/8 inch drive ratchet wrench which will be used by astronauts during Extravehicular Activities (EVA). This battery-powered tool is controlled by a dedicated electonic controller. The PRT was flown during the Hubble Space Telescope (HST) Deployment Mission STS-31 to deploy the solar arrays if the automatic mechanisms failed. The PRT is currently intended for use during the first HST Servicing Mission STS-61 as a general purpose power tool. The PRT consists of three major components; the wrench, the controller, and the battery module. Fourteen discrete combinations of torque, turns, and speed may be programmed into the controller before the EVA. The crewmember selects the desired parameter profile by a switch mounted on the controller. The tool may also be used in the manual mode as a non-powered ratchet wrench. The power is provided by a silver-zinc battery module, which fits into the controller and is replaceable during an EVA. The original PRT did not meet the design specification of torque output and hours of operation. To increase efficiency and reliability the PRT underwent a redesign effort. The majority of this effort focused on the wrench. The original PRT drive train consisted of a low torque, high speed brushless DC motor, a face gear set, and a planocentric gear assembly. The total gear reduction was 300:1. The new PRT wrench consists of a low speed, high torque brushless DC motor, two planetary gear sets and a bevel gear set. The total gear reduction is now 75:1. A spline clutch has also been added to disengage the drive train in the manual mode. The design changes to the controller will consist of only those modifications necessary to accomodate the redesigned wrench. The battery design will be unaffected.

Richards, Paul W.↗
NASA NTRS1964

Optics used to measure torque at high rotational speeds

In measuring torque transmitted by a high speed rotation shaft, an apparatus has been devised which includes a shaft, an optical system and readout servomechanism. This highly accurate method uses only optical contact with moving part and is statically calibrated.

Krsek, A., Jr.↗
NASA NTRS2001

Testing of Face-milled Spiral Bevel Gears at High-speed and Load

Spiral bevel gears are an important drive system components of rotorcraft (helicopters) currently in use. In this application the spiral bevel gears are required to transmit very high torque at high rotational speed. Available experimental data on the operational characteristics for thermal and structural behavior is relatively small in comparison to that found for parallel axis gears. An ongoing test program has been in place at NASA Glenn Research Center over the last ten years to investigate their operational behavior at operating conditions found in aerospace applications. This paper will summarize the results of the tests conducted on face-milled spiral bevel gears. The data from the pinion member (temperature and stress) were taken at conditions from slow-roll to 14400 rpm and up to 537 kW (720 hp). The results have shown that operating temperature is affected by the location of the lubricating jet with respect to the point it is injected and the operating conditions that are imposed. Also the stress measured from slow-roll to very high rotational speed, at various torque levels, indicated little dynamic affect over the rotational speeds tested.

Handschuh, Robert F.↗
NASA NTRS2001

Testing of Face-milled Spiral Bevel Gears at High-speed and Load

Spiral bevel gears are an important drive system components of rotorcraft (helicopters) currently in use. In this application the spiral bevel gears are required to transmit very high torque at high rotational speed. Available experimental data on the operational characteristics for thermal and structural behavior is relatively small in comparison to that found for parallel axis gears. An ongoing test program has been in place at NASA Glenn Research Center over the last ten years to investigate their operational behavior at operating conditions found in aerospace applications. This paper will summarize the results of the tests conducted on face-milled spiral bevel gears. The data from the pinion member (temperature and stress) were taken at conditions from slow-roll to 14400 rpm and up to 537 kW (720 hp). The results have shown that operating temperature is affected by the location of the lubricating jet with respect to the point it is injected and the operating conditions that are imposed. Also the stress measured from slow-roll to very high rotational speed, at various torque levels, indicated little dynamic affect over the rotational speeds tested.

Handschuh, Robert F.↗
NASA NTRS2002

Testing of Face-Milled Spiral Bevel Gears at High-Speed and Load

Spiral bevel gears are important drive system components of rotorcraft (helicopters) currently in use. In this application the spiral bevel gears are required to transmit very high torque at high rotational speed. Available experimental data on the operational characteristics for thermal and structural behavior is relatively small in comparison to that found for parallel axis gears. An ongoing test program has been in place at NASA Glenn Research Center over the last ten years to investigate their operational behavior at operating conditions found in aerospace applications. This paper will summarize the results of the tests conducted on face-milled spiral bevel gears. The data from the pinion member (temperature and stress) were taken at conditions from slow-roll to 14400 rpm and up to 537 kW (720 hp). The results have shown that operating temperature is affected by the location of the lubricating jet with respect to the point it is injected and the operating conditions that are imposed. Also the stress measured from slow-roll to very high rotational speed, at various torque levels, indicated little dynamic affect over the rotational speeds tested.

Handschuch, Robert F.↗