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Showing papers on "Pulley published in 1994"


Patent
07 Feb 1994
TL;DR: An improved surgical stapling instrument for applying surgical staples to human tissue is presented in this paper, which includes a fixed jaw with a staple cartridge and a movable jaw with an anvil for clamping the tissue there.
Abstract: An improved surgical stapling instrument is provided for applying surgical staples to human tissue. The instrument has an articulated stapling head assembly mounted by a rotatable and flexible support shaft on an actuator handle assembly with an improved actuator mechanism for closing and firing the stapling head assembly. The stapling head assembly comprises a fixed jaw with a staple cartridge and a movable jaw with an anvil for clamping the tissue therebetween. The actuator mechanism comprises a jaw closure lever for closing the jaws and a staple firing lever for actuating a staple driver to drive the staples from the staple cartridge into the tissue and against the anvil. The actuator mechanism also includes a cam pulley mounted for rotation by the staple firing lever and secured to a firing cable for actuating the staple driver. A set of drive gears rotatably positioned on opposite sides of the cam pulley mesh with gear sectors on the staple firing lever to rotate the cam pulley and apply tension to the firing cable when the staple firing lever is actuated. The cam pulley has a contoured cam lobe for actuating the firing cable with different mechanical advantages as the pulley is rotated. An anti-backup member engages the cam pulley to prevent the pay-out of the firing cable before and after the staple firing lever is actuated. The length of the support shaft can be adjusted to set the tension in the closure cable so that the jaws are completely closed by the jaw closure lever to produce staples of uniform height when the staple firing lever is actuated.

745 citations


Journal ArticleDOI
TL;DR: In this article, a nonlinear model is developed which describes the rotational response of automotive serpentine belt drive systems, and the model is linearized about the equilibrium state and rotational mode vibration characteristics are determined from the eigenvalue problem governing free response.
Abstract: A nonlinear model is developed which describes the rotational response of automotive serpentine belt drive systems. Serpentine drives utilize a single {long) belt to drive all engine accessories from the crankshaft. An equilibrium analysis leads to a closedform procedure for determining steady-state tensions in each belt span. The equations of motion are linearized about the equilibrium state and rotational mode vibration characteristics are determined from the eigenvalue problem governing free response. Numerical solutions of the nonlinear equations of motion indicate that, under certain engine operating conditions, the dynamic tension fluctuations may be sufficient to cause the belt to slip on particular accessory pulleys. Experimental measurements of dynamic response are in good agreement with theoretical results and confirm theoretical predictions of system vibration, tension fluctuations, and slip.

98 citations


Patent
09 Dec 1994
TL;DR: In this paper, the axial load, applied to the variator pulley units, comprises two parts -a first part to maintain traction between sheaves and band, and a second part related to the applied torque- and a variator using more than one band.
Abstract: A continuously-variable-ratio transmission ("CVT") of the band-and-sheave type capable of "torque control", so that what the operator demands, by movement of the accelerator pedal or other control member, is a particular driving torque applied to the ratio-varying component ("variator"). A connection (21, 22) between at least one of the variator sheaves (3, 4) and its shaft (5) is torque-sensitive, so that torque at that sheave generates an axial force which is a function of the magnitude and direction of the torque to which the sheave is subjected. Examples are described in which the operating axial load, applied to the variator pulley units, comprises two parts -a first part to maintain traction between sheaves and band, and a second part related to the applied torque- and a variator using more than one band.

73 citations


Patent
27 Jun 1994
TL;DR: In this paper, a range of motion splint (10) is used for applying constant torque across a joint undergoing rehabilitation therapy, which includes a first arm (18) and a second arm (20).
Abstract: This is a range of motion splint (10) for applying constant torque across a joint undergoing rehabilitative therapy. The splint (10) includes a first brace section (12) and a second brace section (14). A first arm (18) extends from the first brace section (12) and a second arm (20) extends from the second brace section (14). The first and second brace section arms (18 and 20) are pivotally connected about a splint pivot axis by a pivot mechanism (24). A driven pulley (42) is mounted to the second arm (20) about the splint pivot axis. A drive pulley (56) is rotatably mounted to the first arm (18) about a drive axis which is spaced from the splint pivot axis. Torque is applied to the drive pulley (56) with respect to the first arm (18) by a spiral spring (50) positioned about the drive axis. A belt (30) couples the drive pulley (56) and the driven pulley (42). The amount of torque applied between the brace sections can be adjusted by a torque adjusting mechanism (52 and 54) which winds and unwinds the spring (50). An adjustable stop mechanism (80) can be used to limit the range of rotational motion between the brace sections. The brace section can be locked with respect to one another by a locking mechanism (66) which engages and prevents movement (52 and 54) of the drive pulley (56).

67 citations


Patent
20 Apr 1994
TL;DR: In this article, a variable wheel with a hub, a plurality of extendable ram rods connecting the hub and a shape adaptable rim is described, which adjusts to the most effective, efficient shape for travel over varying surfaces such as asphalt, concrete, sand, mud, rock, snow, ice and others.
Abstract: A variable shaped wheel having a hub, a plurality of extendable ram rods connecting the hub and shape adaptable rim. Extension and retraction of the ram rods cause the rim to harmonize to a selected wheel shape such as horizontal oval, vertical oval, elliptical, tractor like and numerous other shapes, when stationary and while moving. The selected shape of the variable wheel in motion is maintained by continual length adjustment of the ram rods. The variable shaped wheel adjusts to the most effective, efficient shape for travel over varying surfaces such as asphalt, concrete, sand, mud, rock, snow, ice and others, providing optimum speed and comfort. It is another purpose of the present invention, through change in shape of the variable wheel, pulley, gear from conventional circular to oval, elliptical, and shapes other than circular, to make contact at the periphery along the elongated axis with another wheel, pulley, gear, providing for simple and effective rotational energy transmission from one wheel, pulley, gear, to another.

58 citations


Patent
03 Feb 1994
TL;DR: In this article, an exercising machine with an adjustable actuator arm assembly coupled to a weight stack by a pulley/cable assembly is described, which can be rotated through an arc to provide a number of operating locations.
Abstract: An exercising machine that has an adjustable actuator arm assembly coupled to a weight stack by a pulley/cable assembly. The actuator arm assembly includes an actuator arm that lifts the weight stack when rotated through an arc. The machine is constructed with a frame that has a vertical bar. The actuator arm is coupled to a sleeve assembly that can slide along the vertical bar, to provide a number of operating locations. The machine also has a first cable that is coupled to the actuator arm. The cable is looped around a first tension pulley, a first floating pulley and then fixed to the sleeve assembly. The first floating pulley is coupled to a second cable that loops around a second tension pulley and is attached to the weight stack. When the actuator arm is rotated, the first floating pulley is pulled in a downward direction. The movement of the first floating pulley pulls the second cable and lifts the weight stack in an upward direction. When the sleeve assembly is adjusted to a new position on the vertical bar, the cable lengths between the first tension pulley and actuator arm assembly, and between the first floating pulley and sleeve, change an equal and offsetting amount.

54 citations


Patent
04 Feb 1994
TL;DR: A cable and pulley system for a multi-station exercise machine involving a tensioned cable led over a series of pulleys, at least one of which is a cradled pulley normally nested in a cradle and radially held in the cradle by the force of the tension on the tensioned cables, was described in this article.
Abstract: A cable and pulley system for a multi-station exercise machine involving a tensioned cable led over a series of pulleys, at least one of which is a cradled pulley normally nested in a cradle and radially held in the cradle by the force of the tension on the tensioned cable and radially movable out of the cradle by a greater force applied to the cradled pulley by a second pull cable mechanically connected to the cradled pulley and functioning to move the cradled pulley radially out of its cradle when sufficient tensional force is applied to the second cable to overcome the tension applied to the cradled pulley by the tensioned cable. Additional exercise stations can be added to operate with additional cables and cradled pulleys without changing the manner of operation of other cables and exercise stations.

43 citations


Journal ArticleDOI
TL;DR: Findings indicate that repair or reconstruction of either the A1 or oblique pulley after injury will restore normal thumb kinematics.
Abstract: The purpose of this study was to quantify the contributions of the thumb flexor pulleys on the mechanical efficiency and angular joint displacement of the human thumb. Fourteen human (below elbow) cadaveric specimens were divided into two study groups. Four experimental trials were performed with each thumb. Group 1 was tested with an intact pulley system, as well as after sequential sectioning of the oblique, A1, and A2 pulleys. Group 2 was tested with all pulleys intact and following the sequential sectioning of the (A1), oblique, and (A2) pulleys. Each forearm was mounted to a dynamic testing apparatus, and an 815 g load was applied at the thumb tip. The flexor pollicus longus tendon was attached to a force transducer and computer-driven stepper motor, and tension was recorded through full range of motion of the interphalangeal and metacarpophalangeal joints. The initial sectioning of either the A1 or oblique pulley did not significantly alter the thumb efficiency or its interphalangeal or metacarpophalangeal joint angular displacement. When both the A1 and oblique pulleys were cut, significant bowstringing was observed, as well as decreased interphalangeal flexion and increased metacarpophalangeal flexion; total angular motion remained unchanged. The tension required to achieve a given displacement also decreased following the sectioning of both the A1 and oblique pulleys. There was no statistical difference between an isolated, intact A2 pulley and no intact pulleys. These findings indicate that repair or reconstruction of either the A1 or oblique pulley after injury will restore normal thumb kinematics.

43 citations


Patent
04 Jan 1994
TL;DR: In this paper, an apparatus for controlling the angular positioning and stiffness modulations of a joint of a robotic manipulator by use of first and second motors and a control mechanism is presented.
Abstract: The present invention provides an apparatus for controlling the angular positioning and stiffness modulations of a joint of a robotic manipulator by use of first and second motors and a control mechanisms. The first motor, preferably a direct current motor, controls angular positioning, while the second motor, preferably a servo motor, controls stiffness modulations. The angular positioning and stiffness modulations take place simultaneously, yet independently, thereby preventing interference. The first and second motors and the control mechanism are positioned within a housing. The control mechanism includes a shaft support member and threaded and non-threaded shafts. The threaded and non-threaded shafts extend from the first and second motors through threaded and non-threaded apertures, respectively, in the shaft support member to the housing where the threaded shaft is bearing mounted and the non-threaded shaft is supported in an aperture in the endwall of the housing to connect a pulley outside of the housing which is connected to a joint and link arrangement of a robotic manipulator. The shaft support member translates back and forth within the housing dependent on its position on the threaded shaft. When the shaft support member is nearer the housing endwall, the effective length of the shaft is short, the joint is stiff, effectively making the link stiff. When the shaft support member is nearer the shaft connection end of the motors, the effective length of the shaft is longer, the effective spring is soft, effectively making the actuator and link soft.

42 citations


Patent
23 Sep 1994
TL;DR: In this article, an adjustable lifting force of an adjustable magnitude was applied on the patient through the cable (16) and the harness (14) of a walking substrate to enable a limited variation of the length of the cable's bight.
Abstract: An arrangement for practizing walking comprises a treadmill (10) serving as a walking substrate, a harness (14) which may be mounted on a patient (11), a suspension cable (16) connectable to the harness, and a device (19) by which a lifting force of an adjustable magnitude may be applied on the patient (11) through the cable (16) and the harness (14). Said device (19) comprises a pulley (20) around which the cable (16) extends in a bight (41). This pulley (20) is arranged for limited movement in a direction transverse to its rotary axis (22) in order to permit a limited variation of the length of said bight (41). By means of an elastically yieldable force generating means (30), an adjustable force, which is substantially independent of the instantaneous position of said pulley (20), may be applied on the pulley (20) in a direction to cause said bight (41) of the cable (16) to assume its maximum length.

38 citations


Patent
29 Jul 1994
TL;DR: In this article, the authors described a single-stage exercise cycle with a drive wheel and friction brake resistance, which is automatically controlled by an electronic system, which receives actual load information from a load cell, and RPM information from speed sensor.
Abstract: A stationary exercise cycle is disclosed having a drive wheel (40) which receives both user driving force and automatically controlled friction brake resistance, i.e., it is a single stage device. Freewheeling is pivoted between a user driven shaft and the periphery of the drive wheel, which is braked by a friction belt (60). Automatic resistance control is provided by an electronic system, which receives actual load information from a load cell, and RPM information from a speed sensor. The friction belt is tightened or loosened by a motor driven pulley, in response to signals indicating an 'error' between load command and actual load.

Proceedings ArticleDOI
12 Sep 1994
TL;DR: The transmission system of the Utah/MIT Dextrous Hand is investigated theoretically and experimentally and it is shown that the friction of the routing pulleys is not negligible and should be considered in the force control of the UMDH.
Abstract: The transmission system of the Utah/MIT Dextrous Hand (UMDH) is investigated theoretically and experimentally. It is shown that the friction of the routing pulleys is not negligible and should be considered in the force control of the UMDH. In the frequency range of the pneumatic actuators (80 Hz), tendons act like springs and the first mode of the tendons is above that frequency range. >

Patent
20 Dec 1994
TL;DR: In this article, a vibration damper assembly is designed to dampen torsional, bending, and transitional vibrations transmitted from the output shaft through the poly-V belt and engine frame to the belt tensioner.
Abstract: A vibration damper assembly operatively connecting a driving pulley with an automotive engine output shaft which drives a serpentine belt system with an automatic belt tensioner. The vibration damper assembly serves to dampen torsional, bending, and transitional vibrations transmitted from the output shaft through the poly-V belt and engine frame to the belt tensioner. The vibration damper assembly comprises a mounting element, fixed to the output shaft, in torsional transmitting relation therewith, bearing means operatively disposed between the driving pulley and the mounting element to restrict relative movement therebetween to torsional relative movement, and a resilient member operatively connected between the driving pulley and the mounting element in resilient torsional transmitting relation therebetween.

Journal ArticleDOI
TL;DR: In this article, the metal V-belt behavior of a V belt CVT was investigated analytically and experimentally, and it was found that the gross slip points depend on the torque transmission capacity of the driven side.

Patent
17 Oct 1994
TL;DR: In this paper, an actuator cover plate is connected by rods to a lower half of a split pulley, with the upper pulley half mounting a helix or cam cone extending towards the actuator under-surface.
Abstract: The invention in a torque responsive actuator device for a belt drive system as is commonly utilized with snowmobile and like type vehicles. An actuator cover plate of the invention is connected by rods to a lower half of a split pulley, with the upper pulley half mounting a helix or cam cone extending towards the actuator cover plate undersurface that includes a plurality of cam tracks formed therein that are each to receive a cam follower for travel therealong that extends from the actuator cover plate undersurface. Movement of the actuator cover plate towards the top face of the pulley upper half is thereby translated through the rods to spread the pulley upper and lower halves apart, opening a V slot therebetween to a drive belt that is maintained therein. A cylindrical shaft is journaled through the actuator cover plate and fitted through pulley that includes a coil spring disposed therearound for providing spring biasing to urge the actuator cover plate away from the pulley upper half, closing the pulley halves together. To provide minimum friction operation and actuator wear the invention employs cam follower roller bearings as the cam followers and radiuses or forms the cam tracks to have a center apex wherealong a roller of the roller bearing travels through a variety of cam degree angles as the cam followers experience as they travel along the cam tracks during actuator operation.

Patent
21 Dec 1994
TL;DR: In this paper, a block and tackle window balance includes an extension spring and two blocks of pulleys mounted within a rigid channel, and a spring coupling connects a free end of the extension spring to the first block of pulley.
Abstract: A block and tackle window balance includes an extension spring and two blocks of pulleys mounted within a rigid channel. A spring coupling connects a free end of the extension spring to the first block of pulleys. The pulleys of the first block are sized in width to center the spring coupling and the free end of the extension spring within the channel. The second block of pulleys are mounted on an axle that is received in slots formed in the channel. A center portion of the axle guides a pulley cord through the second block for exiting the balance.

Patent
29 Mar 1994
TL;DR: In this paper, a V-belt-type transmission system incorporating a plurality of cam lobes that extend in an axial direction at a predetermined radial distance from the pulley axis is described.
Abstract: A cam for axially shifting the pulley faces of a variable width, torque sensing V-belt pulley in a variable speed, belt-type transmission system. The cam includes a plurality of cam lobes that extend in an axial direction at a predetermined radial distance from the pulley axis. Each cam lobe is triangular and is symmetrical about a cam lobe axis that is parallel with the pulley axis, and each cam lobe includes two cam surfaces that engage with respective cam followers to change the pulley face spacing as the load on the belt changes. The cam surfaces are convex and are in the form of circular arcs. The transmission system incorporating the cam structure is particularly suitable for vehicular use, and it provides improved performance by reducing engine overspeed upon initial acceleration and provides a smoother backshift when climbing hills.

Patent
27 Jan 1994
TL;DR: In this article, a pulley device includes a moveable conical pulley component which is moveable to a stationary conical component by a servo motor, and an auxiliary piston is received in the auxiliary cylinder.
Abstract: A pulley device includes a moveable conical pulley component which is moveable to a stationary conical pulley component by a servo motor. The servo motor includes a cylinder fixedly held with respect to a shaft portion of the stationary conical pulley component, and a piston fixed to the moveable conical pulley component and slidably engaging the cylinder. The servo motor also includes an auxiliary cylinder reduced in diameter than the cylinder and fixed with respect to the shaft portion, and an auxiliary piston fixed to the moveable conical pulley component. The auxiliary piston is received in the auxiliary cylinder.

Patent
25 Jul 1994
TL;DR: In this article, a trapezoidal belt is used to counterbalance the radial force exerted by the trapezoid belt, the helicoidal spring and the internal resultant forces acting alone.
Abstract: In a driven pulley used in a variable speed transmission adapted to receive a trapezoidal belt by which power is transmitted from a driving pulley to the driven pulley having a fixed flange, a movable flange and an internal helicoidal spring, there is provided a set of flyweights forced by torsion springs on an annular-conical surface located at the rear of the movable flange. At the minimum rotation speed, the driven pulley generates a high gripping force but as the rotation speed increases, the centrifugal force acting on the flyweights lowers the force exerted by the trapezoidal belt. At a given high rotation speed, the flyweights leave the annular-conical surface and no longer contribute to counterbalancing the radial force exerted by the trapezoidal belt, the helicoidal spring and the internal resultant forces acting alone. The improved driven pulley generates a high initial gripping force while having a reasonably low gripping force at high speed for good efficiency.

Patent
08 Sep 1994
TL;DR: An unbalance measuring machine has an arrangement for clamping and releasing a motor vehicle wheel or other rotary member on a motor-driven shaft as discussed by the authors, where the machine has a bar which is guided movably in the shaft in its axial direction.
Abstract: An unbalance measuring machine has an arrangement for clamping and release a motor vehicle wheel or other rotary member on a motor-driven shaft. The machine has a bar which is guided movably in the shaft in its axial direction. The bar is engaged at one end with the rotary member and at the other end with a belt pulley via interengaged screw threads. When the belt pulley is driven by the drive motor in one direction of rotation, the bar axially clamps the rotary member on the shaft to hold it fast. When the belt pulley is driven by the drive motor in the other direction, the bar moves in the opposite direction to release the rotary member.

Patent
15 Nov 1994
TL;DR: In this paper, the authors presented an apparatus and method for receiving flat articles having a top edge alignment and horizontal orientation and transporting the articles along a transport path to a vertical orientation and a bottom edge alignment.
Abstract: The present invention provides an apparatus and method for receiving flat articles having a top edge alignment and horizontal orientation and transporting the articles along a transport path to a vertical orientation and a bottom edge alignment. The apparatus comprises a frame, a deck plate adjustably mounted to the frame, and structure for adjusting the position of the deck plate in a direction transverse to the paper path. A pair of entrance pulleys and exit pulleys are each mounted to the deck plate. The entrance pulleys rotate on a horizontal axis and the exit pulleys rotate on a vertical axis. First and second flexible, endless belts, are each wrapped around one of the entrance pulley and the exit pulleys wherein the belts complete a 90 degree twist from the respective entrance pulley to the respective exit pulley. The apparatus further comprises structure for driving the exit pulleys to move the first and second belts in the same direction and at the same velocity for transporting the articles from the entrance location to the exit location, wherein the driving structure is mounted under the deck plate.

Patent
31 May 1994
TL;DR: In this article, a traction control system combines engine output power limiting with a single point brake for controlling wheel slip, which is preferably connected to the engine to reduce torque requirements and avoid drive line shock.
Abstract: A traction control system combines engine output power limiting with a single point brake for controlling wheel slip. The brake is preferably connected to the engine to reduce torque requirements and avoid drive line shock. One friction member of the preferred brake is coupled to the engine block, and another friction member member is coupled together with a drive pulley to the engine output shaft. An electromagnetic actuator moves the two friction members into engagement with each other within a hollow interior of the drive pulley.

Patent
04 Mar 1994
TL;DR: In this paper, parking pallets are supported on endless conveyor belts at the sides which are associated with a driving guide pulley (4) which is driven with a single shaft (11) to form the single drive element for the belts.
Abstract: The parking pallets (1) are supported on endless conveyor belts (3) at the sides which are associated with a driving guide pulley (4) which is driven with a single shaft (11) to form the single drive element for the belts The pallet is lifted from the belt (3) by a lift mechanism whose rollers which support the pallet can rotate about rotary axes running perpendicular to those of the guide pulleys of the endless belts Each endless belt can be guided round two guide pulleys (4,5) between which are mounted several support rollers which support the upper side of the endless belt Each belt pref only extends over the dimensions of one pallet and several such belts can be arranged adjoining one another in modular formation

Patent
12 Dec 1994
TL;DR: In this article, a trimming device consisting of a platform, a plurality of wheels and cutters is used for trimming a rigid obstacle, where the cutting blades are pivotally mounted to the cutting pulleys so that they may free float and recoil in response to contacting rigid obstacles.
Abstract: A trimming apparatus comprising a platform, a plurality of wheels and a plurality of cutters. The platform has a kickback capability and is biased into an operable position, but capable of kicking back when the apparatus contacts rigid obstacles during the trimming operation. The cutting elements include a plurality of flexible blades having a cutting radius larger than the guide disks which are provided to contact obstacle and help the invention be steered around such obstacles. Optional bumpers are provided to further enable the device to "ride over" obstacles and uneven ground terrain. An independent power source such as an electrical or combustible engine having a drive shaft connected to a drive pulley which in turn is interconnected with the cutting elements by a cutter pulley and idler pulley arrangement so as to maintain a desired tension on the drive belt during operation of the device. The cutting blades are pivotally mounted to the cutting pulleys so that they may free float and recoil in response to contacting rigid obstacles.

Patent
04 Apr 1994
TL;DR: In this article, an accessory drive system for an automotive engine includes a drive pulley attached to an output shaft of the engine and a flexible drivebelt for connecting the drive and driven pulleys.
Abstract: An accessory drive system for an automotive engine includes a drive pulley attached to an output shaft of the engine and a flexible drivebelt for connecting the drive pulley with driven pulleys. A tensioner maintains the drivebelt in contact with each of the drive and driven pulleys. The tensioner includes an arm which is rotatably mounted to the engine which has a wheel for contacting the drivebelt. The wheel is urged into contact with the drivebelt by the arm, with the tensioner further including a governor for controlling rotational motion of the arm with the arm being able to rotate freely in the direction in which tension of the drivebelt is increased, with the governor resisting motion of the arm in the direction in which tension in the drivebelt is decreased.

Patent
14 Jun 1994
TL;DR: A feeder wheel has a top surface and a peripheral edge, with volumetric measuring cavities upon at one end to the top surface of the wheel and at a lower end to said edge.
Abstract: A feeder wheel has a top surface and a peripheral edge, with volumetric measuring cavities upon at one end to said top surface and at a lower end to said edge An endless belt is entrained about a portion of the edge, covering cavity outlets open to said edge, but said belt is pulled away from said edge by a pulley at one side of the wheel Product is dispensed from the cavities when their outlets are uncovered by the belt as the wheel turns The cavities are filled by dropping product onto the top surface of the wheel and by gradually plowing the product over and into the cavities The final plow is slightly curved over a number of cavities so the last product cut is gently performed to increase repeatable volumetric accuracy of product in each cavity A method of feeding volumetric measured product includes dropping product onto the side of a wheel, sweeping the side to move product into volumetrically sized cavities in the wheel, turning the wheel and dispensing products radially from cavity outlets in the wheel edge when uncovered by a belt partially entrained about the wheel edge

Journal ArticleDOI
01 Apr 1994
TL;DR: In this article, the authors investigated the belt-related torque loss in a steel V-belt CVT and proposed a semi-empirical model to explain the loss, which showed that the loss is dependent on the secondary pulley clamping force and on the belt configuration.
Abstract: To achieve the potential advantages to be gained by the use of a high ratio range, continuously variable transmission (CVT) in an automobile it is important that the system has a high efficiency and that any inherent loss mechanisms are fully understood.This paper investigates the belt-related torque loss in a steel V-belt CVT. Measurements show that the loss is dependent on the secondary pulley clamping force and on the belt configuration and these results are presented in the paper. A semi-empirical model is proposed to explain the loss. The agreement between the measured results and the values calculated from the model is shown to be good.It is also shown that when the system is in an overdrive ratio and a high efficiency is particularly important the torque loss is large and the efficiency is severely limited, probably to less than 90 per cent.

Patent
31 Oct 1994
TL;DR: In this article, a mechanically driven centrifugal air compressor for an internal combustion engine has an impeller shaft supported in a compressor housing with journal bearings, and passages are provided for delivering oil under pressure to the deep end of the oil pockets to hydrodynamically transfer the net axial load from the thrust ring to the thrust bearing.
Abstract: A mechanically driven centrifugal air compressor for an internal combustion engine has an impeller shaft supported in a compressor housing with journal bearings. A helical pinion gear is formed on one end of the impeller shaft and an impeller is attached to the other end. A thrust ring mounted on the impeller shaft near the impeller is sandwiched on one side by a thrust bearing and on an opposite side by the nearest journal bearing and the housing to axially locate the impeller shaft. An internal helical ring gear is rotatably supported on the compressor housing and driven by a pulley that is engaged by a belt that is driven by a pulley of larger diameter fixed to an engine crankshaft. The ring gear meshes with the pinion gear to provide a high overdrive speed ratio in series with the belt and pulley drive from the engine crankshaft which provides a low overdrive speed ratio. The thrust bearing bears the axial load on the impeller shaft imposed by air pressure acting on the impeller and the lead of the helical pinion gear is set in a direction so that the gears impose an axial force on the impeller shaft that is opposite the impeller imposed axial force to substantially reduce the axial load borne by the thrust bearing. The thrust bearing is provided with a plurality of oil pockets opposite the thrust ring having a depth that decreases from a deep end in the direction of thrust ring rotation. And passages are provided for delivering oil under pressure to the deep end of the oil pockets to hydrodynamically transfer the net axial load on the impeller shaft from the thrust ring to the thrust bearing.

Patent
16 Sep 1994
TL;DR: In this article, a wheel with circumferential rim and track, a housing in which the wheel is disposed and a plurality of rollers disposed within the housing in rolling engagement with the track to locate a wheel axially and radially within the house.
Abstract: Rotatably supported, regenerative fluid treatment wheel assemblies include a wheel with circumferential rim and track, a housing in which the wheel is disposed and a plurality of rollers disposed within the housing in rolling engagement with the track to locate a wheel axially and radially within the housing. Seal flanges are provided projecting radially outwardly from the rim and are opposed by flexible seals which are clip mounted to walls of the housing surrounding openings through those walls which are aligned with the wheel. At least one wheel is preferably spring loaded so to compensate for any eccentricity in the wheel. The wheel is belt driven. A subassembly, including a mounting plate, flange-mounted motor, drive pulley and spring loaded idler pulley is provided for easy installation and removal. Wear strips appropriate for contact with either the seal flanges or face of the wheel core are applied to the flexible seals by pressure sensitive adhesive. Roller support and location can be applied to hub and spoke wheels as well. Rollers support and location permits the use of a smaller hub and a single bearing, thereby minimizing the center area of the core lost to fluid treatment.

Patent
17 Mar 1994
TL;DR: In this article, an apparatus for both manual and powered operation of the sash of a double-hung window, including a drive belt adjacent one side of a sash, a power drive for the belt, and a pulley carried with sash and engaging the belt is described.
Abstract: An apparatus for both manual and powered operation of the sash of a double hung window, including a drive belt adjacent one side of the sash, a power drive for the belt, and a pulley carried with the sash and engaging the belt. Two ratchets having wheels with oppositely facing inclined teeth and pawls biased into engagement with the wheel of the respective ratchet through a connecting shaft secure the pulley against pivoting in either direction to effectively lock the pulley relative to the engaged belt. A ratchet housing is disposed in a sash recess and has a D-shaped opening on one end adjacent a cylindrical opening to the pulley. A bushing for the ratchet shaft is received in the sash cylindrical opening and includes a D-shaped flange receivable through an annular opening in the housing whereby twisting of the bushing misaligns the flange with a suitable tab to secure the bushing in the sash cylindrical opening. A manually graspable sash lift extends into the housing and when manually biased is movable a limited amount relative to the sash whereby the pawl of the ratchet which secures the pulley against pivoting in the direction required to allow the sash to move relative to the belt in the direction of the manual bias is disengaged from the ratchet wheel. The sash lift is also manually engageable to laterally move the shaft out of engagement with the pulley so as to permit the sash to be disconnected from the pulley for maintenance.