Showing papers on "Pressure angle published in 2006"

Mechanical Error Analysis of Disk Cam Mechanisms with a Flat-Faced Follower

Abstract: By employing the concept of equivalent linkage, this paper presents an analytical method for analyzing the mechanical errors of disk cam mechanisms with a flat-faced follower. The resulting error equations do not really involve the location of the curvature center of the cam profile, and locating the curvature center of the cam profile is not essential. The resulting errors are significantly affected by the pressure angle, and the smaller pressure angle will result in the smaller mechanical error. In the worst case, owing to the joined effects of various design parameters, the accuracy of the follower motion may degrade considerably. For the oscillating follower case, all acceleration error functions have a sudden change at every beginning and at every end of the motion even though the theoretical follower displacement is cycloidal motion.

Multiple-Row Angular Contact Antifriction Bearing, Particularly For Mounting the Bevel Pinion Shaft in a Motor Vehicle Rear Axle Differential

Abstract: The multiple-row angular contact antifriction bearing has an outer bearing ring, an inner bearing ring, and roll bodies, which are arranged at least in two rows next to one another between the bearing rings. The roll bodies are ball discs having two lateral surfaces that are symmetrically flattened from a spherical basic shape whose raceways are arranged inside the bearing rings, abutting against one another so that the respectively adjacent roll bodies of each row have their lateral surface pointing toward one another and arranged directly next to one another on a transversal axis situated at a right angle to the pressure angle axes. These lateral surfaces also provide mutual guide surfaces.

Optimum Design on Lobe Shapes of Gerotor Oil Pump

Abstract: A gerotor pump is suitable for oil hydraulics of machine tools, automotive engines, compressors, constructions and other various applications. In particular the pump is an essential machine element that feeds lubricant oil in an automotive engine. The subject of this paper is the theoretical analysis of internal lobe pump whose the main components are the two rotors. Usually the outer one is characterized by lobes with a circular shape, while the inner rotor profile is determined as a conjugate to the other. For this reason the first topic presented here is the definition of the geometry of the rotors starting from the design parameters. The choice of these parameters is subject to some limitations in order to limit the pressure angle between the rotors. Now we will consider the design optimization. The first step is the determination of the instantaneous flow rate as a function of the design parameter. This allows us to calculate three performance indexes commonly used for the study of positive displacement pumps: the flow rate irregularity, the specific flow rate, and the specific slipping. These indexes are used to optimize the design of the pump and to obtain the sets of optimum design parameter. Results obtained from the analysis enable the designer and manufacturer of the oil pump to be more efficient in this field.

Hydraulic gear pump

Abstract: The utility model relates to a hydraulic gear pump from single link to multiple link. The gear pump is composed of a front pump cover arranged on the left, a pump body arranged in the middle, and a pump body arranged on the right which are fixedly connected to form a whole, a pump cavity in the pump body is respectively provided with double-link meshed driving gears and driven gears in parallel, and both end faces of the driving gears and driven gears, which are appressed with a fixed side plate, are respectively provided with a floating side plate; the hydraulic gear pump can reduce the leakage of an end face, and enhances volumetric efficiency; the interstice between the pump cavity of the pump body, and the gear tops of the driving gears and driven gears is controlled between 0.03mm and 0.01mm, the leakage is reduced, and the volumetric efficiency is further enhanced; the pressure angle between the driving gears and driven gears is enlarged to 31 DEG, and the packeted oil area is reduced. The hydraulic gear pump has the advantages of no leakage of the end face, little leakage of the peak, low temperature of lubrication oil, light total weight, strong strength, long service life and less noise.

Generating standard 20° involute pinions with increased fillet strength by using 25° rack cutters with non-standard module

Abstract: According to all prevailing standards for gear design, a strict guideline is that the individual gears of a gear pair must be of the same module and pressure angle in order to mesh properly...

Transmitting torque limiting apparatus for vehicle

Abstract: A transmitting torque limiting apparatus, used in a power transmitting apparatus, includes side gears (40) and side gears piece (42) one of which are axially shiftable. The side gears (40) and the side gear pieces (42) respectively have first engaging teeth (60 a) and second engaging teeth (60 b) each being provided with a pressure angle (Alpha). Due to such pressure angle, when an excessive torque is inputted into the power transmitting apparatus, a thrust force (F1) is generated for disengaging the engagement between the first engaging teeth (60 a) and second engaging teeth (60 b). Thus, inputting of the excessive torque into the power transmitting apparatus can be limited.

Cornu's spiral tooth gear

Abstract: A Cornu's spiral is applied to a tooth profile of a gear. In accordance with the application of the gear, the Cornu's spiral may be modified two-dimensionally by some constant proportion. Since Cornu's spirals have similarity are similar, when a pressure angle is determined, the tooth profile can be standardized by a module, so that it is highly versatile. By replacing the tip of a tooth and the bottom of a tooth by another curve, such as an arc, the range of application can be increased. Since working is always by flank contact between a protrusion and a recess, contact surface stress is low. In addition, the radius of curvature of a dedendum is large. Therefore, tooth bending stress is low, and fatigue strength is high. Even if the number of teeth is small, an undercut is not produced. Even if there is no backlash, a smooth working is achieved, so that the tooth profile is suitable for devices requiring precise alignment.

Optimum design on the lobe shapes of Gerotor Oil Pump

Abstract: A gerotor pump is suitable for oil hydraulics of machine tools, automotive engines, compressors, constructions and other various applications. Especially the pump is an essential machine element of an automotive engine to feed lubricant oil. The subject of this paper is the theoretical analysis of internal lobe pump whose the main components are the rotors: usually the outer one is characterized by lobes with circular shape, while the inner rotor profile is determined as conjugate to the other. For this reason the first topic presented here is the definition of the geometry of the rotors starting from the design parameters. The choice of these parameters is subject to some limitations in odor to limit the pressure angle between the rotors. Now we will consider the design optimization. The first step is the determination of the instantaneous flow rate as a function of the design parameter. This allows us to calculate three performance indexes commonly used far the study of positive displacement pumps: the flow rate irregularity, the specific flow rate, and the specific slipping. These indexes are used to optimize the design of the pump and to obtain the sets of optimum design parameter. Results obtained from the analysis enable the designer and manufacturer of oil pump to be more efficient in this field, and the system could serve as a valuable one for experts and as a dependable training aid for beginners.

On the Invariance of Gear Tooth Curvature

Abstract: A method is presented for the determination of the principal curvatures along with their principal directions of two gear teeth in direct contact. The procedure used to determine these extreme curvatures and directions is based on the nominal position of contact. Moreover, these extreme curvatures and directions are invariant with tooth type (viz. involute and cycloidal) and manufacturing process. Such curvatures and directions depend on the instantaneous pressure angle, spiral or helix angle, and position of contact. This generalized method is applicable to cylindrical gears (spur and helical), conical gears (straight and spiral), as well as hyperboloidal gears (hypoid and worm). Three examples are included to illustrate the determination of principal curvatures and directions. The first example is a helical gear pair, the second is a spiral bevel gear pair, and the third example is a hypoid gear pair.

Design of Noncircular Gears to Minimise Shaft Accelerations

Abstract: This paper presents a novel pair of noncircular gear profiles for minimising shaft accelerations of the driven gear. The proposed profiles are developed based on an “exponential” function that is valid for a portion of gear rotation, and this function is extended to the remaining parts of the rotation of both gears. The exact shapes of the centrodes of the toothed bodies, which depend on a “smoothness” parameter, b, constitute a trade-off between the maximum shaft acceleration and the smoothness of the centrodes, so as to control the maximum tooth dynamic forces and stresses. A comparison between the derived noncircular gears and a gear pair that provides a sinusoidal variation of the angular velocity is presented. Results indicate that, for two-lobule gears, the maximum and minimum values of the polar radii, the velocity at the contact point, and the gear ratio are the same for both profiles. In contrast, there are significant differences in the angular acceleration of the driven gear, the tangential acceleration at the contact point, and the pressure angle, especially in the first one. It is concluded that the derived pair not only can provide low shaft accelerations, but also low tangential accelerations and small pressure angles.Copyright © 2006 by ASME

Shaving cutter for processing gear

Abstract: The utility model relates to a shaving cutter for processing a gear The shaving cutter comprises a disc cutter body 1 and a shaving cutter teeth 2 which are evenly distributed The utility model is characterized in that the front cutter face 3 of a cutting edge of a chip flute of the shaving cutter is vertical to a tooth face 4, the meshing angle of the shaving cutter 2 is smaller than the pressure angle within the range of 0 DEG to 3 DEG, and the crossed axial angle is selected within the range of 12 DEG to 15 DEG according to the module of the gear Simultaneously, the thickness and the diameter of the cutter body 1 are increased, the shape of each chip flute is changed, and the number of the chip flutes is increased The utility model breaks the conventional design that the meshing angle is increased The utility model chooses the proper crossed axial angle and corrects the tooth profiled of the shaving cutter by making use of the pressure angle correcting method, the curvature tonicity method, the peak reducing and valley filling method, etc Thereby, the precision of the shaving gear and the durability of the shaving cutter are improved greatly

Gear with cornu's spiral tooth profile

Abstract: A gear with a Cornu's spiral tooth profile, wherein a Cornu's spiral is used in the tooth profile thereof. The Cornu's spiral may be two-dimensionally deformed at a specified rate according to the application of the gear. Since the Cornu's spiral comprises a similarity, when a pressure angle is determined, the tooth profile can be standardized by module and can provide high usability. The application of the gear can be further increased by replacing the portions of the addendum and the dedendum of the gear with other curves such as circular arcs. The engagement of the gear is always performed by the surface contact of a projected surface on a recessed surface. Accordingly, since a contact surface pressure is low and the radius of curvature of the dedendum is large, the bending stress of the teeth of the gear is low and the fatigue strength thereof is also high. Even if the number of teeth is low, undercut does not occur in the teeth of the gear. Since the gear can be smoothly engaged without backlash, it can be suitably used for apparatuses for which accurate positioning is requested.

Study on Eccentricity and Minimum Geometrical Center Distance of the Eccentric Involute Gears Transmission

Abstract: The traditional design and analysis method for the eccentric involutes gears transmission has model error. Some important parameters, such as minimum geometrical center distance and eccentricity, are not calculated accurately. The differential equation of eccentric involute gears transmission is established on account of the geometrical relationship of eccentric involute gears transmission. A calculating method of the geometrical center distance and eccentricity are derived. The relationship between the minimum geometrical center distance or maximum transmission ratio and initial meshing angle and eccentricity are analyzed. The minimum geometrical center distance and eccentricity are fitted by polynomial. The analysis and design can be completed fast and accurately by using polynomial fitting formals, so the process of analysis and design are simplified.

Big pressure angle negative profile shifted gear for hydraulic gear pump

Abstract: This invention discloses involute cylinder gear used in hydraulic gear pump, whose tooth shape is negative addendum modification 30 degree pressure angle. Said invention has small volume, light, long service life, no undercut and low noise etc advantages.

A Parallel Indexing Cam Mechanism with Internal Placed Followers

Abstract: A new type of parallel indexing cam mechanism is discovered. The composition of the cam profile is proposed and the formulas of the mechanism parameters are established by synthesis of its configuration and size. The equations for working profile and pressure angle of the cam are derived based on the inverse model and the derivative of pitch curve of cams. An example is given and demonstrates that it is available to design the new mechanism using the derived expressions.

Mechanical reduction gear and electrophotographic image forming apparatus

Abstract: PROBLEM TO BE SOLVED: To constitute a reduction gear train having a reduction ratio 1/10 to 1/25 by one-step speed reduction by checking up a reference rack for tooth profile production to make high image quality obtainable by being used for an image forming apparatus and most appropriately setting the respective dimensions of the reference rack. SOLUTION: The mechanical reduction gear is equipped with the reduction gear train consisting of two gears and having the reduction ratio 1/10 to 1/25 by the one-step speed. The gears of the tooth profiles produced by the reference rack 20 to enable tooth profile generation of the tooth profiles of the teeth of a pressure angle α=20°, the size of teeth ranging from 0.1 to 0.5 m (m=module), addendum of a height ranging from hf ≥1.0 m to ≤1.25 m, and tooth thickness So=0.45 pitch are used. COPYRIGHT: (C)2007,JPO&INPIT

Double-vortex pressure motor

Abstract: In previous attempts to construct a perpetual motion machine, each device ha s found its own equilibrium without producing the anticipated results. The Double-vortex Pressure Motor employs at least two small 'vortex' gears which are engaged with each other, and fixed to a two-shaft bogie. The bogie (and its two vortex shafts) 'fall' between two 'back-eddy' gears whose shafts are fixed to a chassis. On the back-eddy (BE) shafts, and the vortex shafts, are also 'reaching' (large diameter) gears. Perpetual feed-back loops are created by returning the spin gained in both BE gears to the vortex gears via large 'bridging' gears which connect to both the big reaching gear on a BE shaft, and the reaching gear on a vortex shaft which is two wheels away (so that the spin direction is compatible). Reaching arms which join the bridge shaft to the BE and the vortex shafts, work as independently hinging arms. which allow the vortex bogie to fall slightly without compromising contact with the BE shafts. The reaching gears and bridging gears are sufficiently big that they do not come into contact with a fixed position shaft when they fall slightly. While the smaller (slightly separating) vortex gears might function more efficiently with a smaller pressure angle (eg. 14 1/2 degrees) owing to the slight separationwhich occurs when it fall s slightly out of the multi-shaft equatorial which is described when the bogie is in a 'neutral' position, the bridging a nd reaching gears might operate better with a larger pressure angle, and greater available backlash (eg. 20 degrees ), to avoid cramping at the initiating slight-fall event of the vortex 'floating' gears. The initiating event occur s either through the force of gravity on the floating elements, or through a simulated 'gravity' caused when a lever is applied, or through means discussed briefly below. In a two wings variation, two mini-motors may operate cooperatively when the y are related to both sides of a middle Keel Gear and Sprocket, and by sprocket chain they share in common. Chain orbits from each end BE shaft/sprocket, over the middle keel sprocket, and thence to the BE sprocket at the opposite end of the motor. The Double-vortex Motor does not require weight/mass to motivate it, but can of course respond to the imposition of mass within a gravitational field. It can also respond to the simple manual push or pull of a lever arm, or to heat activation, to permanent magnetic force, to electro-magnetic force, to sprin g force, to pulley leverage, to block and tackle advantage, to hydraulic, or to pneumatic advantage. However, in most cases sited above, it doesnot require am involvement with electricity in order to function: it may operate in any positional attitude (there is no 'up' or down necessarily, except for descriptive purposes) and does not require al gravitational field, so it may operate quite satisfactorily in outer space, or within a fluid/liquid environment.

Rolling method and device for forming gear

Abstract: PROBLEM TO BE SOLVED: To provide a rolling method and a rolling device for forming a gear which can shorten cycle time and lengthen the life of tools. SOLUTION: In the invented rolling method for forming the gear, roller dies 2 of which outer periphery is equipped with a plurality of working teeth 3A-3C for rolling are forced into the periphery of a disk workpiece W at a specified forcing speed while being rotated synchronously with the disk workpiece W, whereby the working teeth 3A-3C of the roller dies 2 perform rolling to the periphery of the disc workpiece W so as to form a gear-shaped member. The rolling method comprises a first working step and a second working step. In the first step, intermediately rolled teeth W2 are formed by means of the roller die 2A equipped with the working teeth 3A having a pressure angle larger than that specified for the final tooth profile. In the second step, rolled teeth 3B and 3C are formed onto the rolled teeth W2 formed in the first step, by means of the roller dies 2B and 2C equipped with the working teeth 3B and 3C having the pressure angle specified for the final tooth profile. COPYRIGHT: (C)2006,JPO&NCIPI

Straight and inclined gear linkaged speed changing gear

Abstract: The utility model relates to a straight and inclined gear linked speed changing gear which is composed of a straight gear (1) and a worm gear (2) which are made into a whole, wherein the low width a for the tooth of the worm gear (2) is 0443 millimeters to 0668 millimeters The thickness b for the tooth top of the straight gear (1) is 076 millimeters to 085 millimeters The utility model thickens the tooth shape of the worm gear and the straight gear a lot, and thus a pressure angle in the radial direction is changed; resistance in the radial direction is small during operation, and the strength for the tooth shape of the worm gear is enlarged; when power is enlarged, a large worm gear is not needed, and the volume of a speed changing box does not need to be enlarged; axial force is more mutually balanced during working Thus, effective output to the power is improved, when noise is reduced simultaneously, the driving is more reliable without an adjusting device

A research for influence of the gear pressure angle on tooth surface contact intensity

Abstract: The influence of gear pressure angle on gear intensity is analyzed by the theory of Hertz contact.The law of gear intensity changed with gear pressure angle is obtained.It is found that the contact principal stress and shearing strength in tooth surface are reduced with the augmentation of gear pressure angle.The conclusion obtained from the research is favorable for improving the intensity of gear and preventing erosion of tooth surface,it is useful to the design of the heavy-load gear.

CAD Graphical Method for Designing Cylindrical Cam Mechanisms with Oscillating Follower

Abstract: According to the concept of instantaneous velocity center,the simple expression for the pressure angle of cylindrical cam mechanisms with oscillating roller follower can be derived,and the CAD graphical method to optimize the minimum average cylinder radius is put forward, and processing for designing cylindrical cam mechanisms based on AutoCAD is introduced.

Dressing method of honing stone

Abstract: PROBLEM TO BE SOLVED: To dress a honing stone in correspondence with a honing gear different in a tooth surface, especially in a pressure angle error without preparing a plurality of kinds of dress gears. SOLUTION: A position on a changing region to pressure-weld on a tooth surface of the honing stone is set in accordance with the tooth surface of the honing gear by using the dress gear larger in tooth width than the honing gear as the dress gear and furnished with a tooth surface having the changing region where the pressure angle error against a standard tooth profile continuously changes in the tooth width direction. COPYRIGHT: (C)2006,JPO&NCIPI

The Design of Noncircular Gear of Constant Pressure Angle and the Realization of Its Wire-Electrode Cutting

Abstract: This paper brings forward a new type of the tooth profile of noncircular gear—constant pressure angle involute tooth profile, and realizes its wire-electrode cutting. By the design of CAD and CAM, this paper shortens the design time of the noncircular gear and improved the design accuracy of the noncircular gear. By the research of the constant pressure angle involute tooth profile of noncircular gear, this paper has improved the transmission accuracy of the noncircular gear. By the research of the technology of wire-electrode cutting, this paper has improved the manufacturing accuracy of the noncircular gear.

Wire-feeding wheel for wire feeder for welding machine

Abstract: The utility model relates to a wire feeding wheel of a wire feeder for welding machines. The utility model comprises a wire feeding wheel (11) and a pressing wheel (12), wherein welding wires are positioned in a V-shaped groove on the wire feeding wheel (11), and are fed through the wire feeding wheel (11) and the pressing wheel (12). The angle of the inside of the V-shaped groove is between 52 and 55 degrees. The utility model has the advantage that the welding wires only need bearing small pressures as the pressure angle is small. Meanwhile, enough friction force between the welding wires and the wire feeding wheel is assured. Thus, the welding wires can be stably fed under the condition that pressure on the welding wires is small (the welding wires are prevented from deforming). Thus, the feeding form is largely simplified.

Probabilistic Analysis of MEMS Asymmetric Gear Tooth

Abstract: Asymmetric gear teeth are used to improve the performance of gears by increasing the load capacity or by reducing vibrations. Recently these types of gears have found application in MEMS devices where the use of gears is on the rise. In this research a probabilistic computer program, in conjunction with a commercially available finite element program, is developed and the reliability of the asymmetric gear tooth is studied. Specifically, the probability of failure of the asymmetric gear is extracted for various parameters. The parameters considered included pressure angle, tooth height, and contact ratio. The efficacy of using asymmetric gear tooth is shown in this study.Copyright © 2006 by ASME

Kinematics of Spherical Multi-Lobe-Cams for The Design of a Pitch-Roll Wrist

Abstract: Cam-roller mechanism can be used in transmissions and robotic devices as an alternative to their bevel-gear counter-parts. Compared with gear transmissions, cam-roller mechanisms feature low friction, low backlash, and high strength. However, cam mechanisms may end up with a high pressure angle if negative action, a motion in which the cam is driven by rollers, occurs. This paper reports the design of transmissions with multi-lobe-cams (MLC), as a means to reduce the pressure angle. The kinematics problems associated to MLC, including profile generation and transmission errors, are studied. As an example, a pith-roll wrist designed with MLC is described.

Influence analysis on the elasto-hydrodynamic lubrication affected by pressure angle of gear

Abstract: The influence of elasto-hydrodynamic lubrication affected by pressure angle of gear was analyzed by the use of elastic fluid lubrication theory.It is discovered that the variation of pressure angle of gear made no obvious influence on the parameters of elasticity and parameters of viscosity. But the increase of pressure angle will cause an evident increase on the least thickness of oil-film and on the specific thickness of oil-film,these will extremely beneficial to the improvement of tooth surface lubrication and provided theoretical basis for the design of heavy load carrying gears.

Cone hub unit assembly for large-sized passenger vehicle

Abstract: The utility model relates to a cone hub unit assembly for a large-sized passenger vehicle, which comprises an outer hub unit ring, wherein the inner side of the outer unit ring is assembled with an inner angle contact ring; a race which is processed at the inner side of the outer unit ring is arranged between the inner ring and the outer unit ring; a rolling body is arranged in the race, and is a lengthening type conical roller. The race is provided with a pressure angle, and the length and the pressure angle of the race are matched with the length and a cone angle of the rolling body. The utility model has the advantages of reasonable integral structure, high carrying capacity, simple structure, convenient installation and reliable lubrication.