564 results about "Pressure angle" patented technology

A sprocket and a roller chain drive system including same are disclosed. The sprocket is a random engagement sprocket comprising a first plurality of A-profile teeth formed with a first asymmetric profile and a second plurality of B-profile teeth formed with a second asymmetric profile. The A-profile teeth each define a first pressure angle and the B-profile teeth each define a second pressure angle that is at least 5 degrees greater than said first pressure angle so that a minimum separation Δ is defined. The sprocket is defined with added chordal pitch reduction of 0.2% up to 1% relative to the link pitch of the associated roller chain. The sprocket can be defined with root relief and/or can comprise resilient cushion rings. Initial roller contacts made with the A-profile and B-profile teeth are modulated owing to the pressure angle separation and added chordal pitch reduction.

The invention relates to a comprehensive demonstrating teaching tool for a cam mechanism. The comprehensive demonstrating teaching tool comprises a driving device, an ordinary gear train (16), an epicyclic gear train (5), a cam (25), a bottom plate (26), a ratchet mechanism (9) and a push rod (19). The ratchet mechanism (9) comprises an inner ratchet wheel (901), a ratchet wheel cover (904), a pawl (902) and a reset spring (903). The cam (25) is fixedly connected with the ordinary gear train (16) through a tie bar (15), and an output shaft (6) is arranged outside the tie bar (15) in a sleeved mode. The bottom plate (26) is provided with a sliding block (20), and the push rod (19) moves along the sliding block (20). The cam mechanism demonstrating teaching tool can vividly and visually demonstrate the reversal method, the cam profile design, the push rod motion law drawing, the cam mechanism pressure angle demonstration and other knowledge points, a teacher can teach conveniently, students can manually experience the characters of the cam after class, and the study enthusiasm of the students is improved to a maximum extent.

A high-precision small modulus gear vision measurement method is disclosed. The method is characterized by after a CCD camera is calibrated, carrying out small modulus gear coordinate conversion, outputting an actual physical coordinate of a small modulus gear and calculating a correlation parameter coordinate scale factor, a rotation matrix and a translation matrix; reflecting a space position relation between a gear to be measured and a measurement system in the measurement system; carrying out image processing, wherein a processed object is a small modulus gear edge contour image acquired from a CCD camera 3; and carrying out denoising; then using and carrying out 1/8 sub-pixel edge extraction, extracting an edge point coordinate, carrying out center fitting and acquiring a center coordinate of the image; according to an edge point, acquiring a basic gear parameter, wherein the basic parameter is a tooth number, a mode number, a reference circle diameter and a pressure angle; fitting a standard gear contour curve; and comparing an actually-acquired edge contour curve with a theoretical contour curve so as to acquire a pitch deviation and a tooth profile deviation. The basic gear parameter and quality can be comprehensively analyzed and evaluated.

An internal planetary gear mechanism reduces a load applied to tooth surfaces of an external gear and an internal gear, a sliding portion such as a bearing and the like. By setting the amount of eccentricity α of an eccentric part to be larger than a theoretical value, a distance between the center of the external gear and the center of the internal gear is increased to allow the reduction of a loss in the bearing and on the tooth surfaces of the gears, and a mesh zone between the internal gear and the external gear can be reduced to decrease a part at a large pressure angle, thereby reducing a loss generated by a large pressure angle. As a result of reduction in the mesh zone between the external gear and the internal gear, rolling contact of the gears is maintained.

A wave gear device has a rigid internal gear, a flexible external gear, and a wave generator. The tooth profiles of both gears are initially defined by a basic rack tooth profile shape. The lower parts of the dedendum portions of these tooth profiles are modified by curves C2 and C3 having pressure angles α2 and α3 that are less than the standard pressure angle α1 of the basic rack tooth profile shape C1. An increase in thickness of the tooth bottom side can be minimized even if the tooth depth is increased and the tooth thickness/tooth space ratio changed to increase the tooth thickness. Hence, the ratcheting torque of a wave gear device having a high reduction gear ratio can be increased without reducing the service life and strength of a pinion cutter for the rigid internal gear, or the fatigue strength of the flexible external gear.

A rack-and-pinion steering apparatus comprises pinion teeth formed according to proper tooth specifications in other aspects under a larger pressure angle, thereby stably offering smooth and comfortable steering feeling over a long time. The module (m), number of teeth (z), tooth depth(h) and helix angle (β) of the pinion teeth (4) are set within the following ranges, under a pressure angle (α) set within a range of 24° to 30° and a given stroke ratio.

• • module (m): 1.8 to 2.0
  • number of teeth (z): 7 to 13
  • tooth depth (h): 2 m to 2.5 m
  • helix angle (β): 350 or smaller

The invention discloses a powder metallurgical internal inclined gear, according to weight percent, containing elements Cu 1-3%, Ni 1-3%, Mo 0.1-1%, and the rest Fe and unavoidable component, where its spiral angle is not greater than 35 degrees, its pressure angle is 5-25 degrees, and its mode is 0.5-2.5 degrees. It mixes the alloy powder of Cu, Ni and Mo to make press molding, firing and shaping so as to make it. Its making mould is top, bottom and middle moulds and core stick. It gears stably and accurately, has small friction coefficient and low mechanical noise. It adopts special designed mould, presses by mould core's rotary ascending or descending along screw, which converts the rotary pressing into axial pressing, can press internal inclined gears of various spiral angles.

A gear grinding machine comprises: a moving mechanism rotatably mounted with a threaded grinding wheel, and arranged to move the threaded grinding wheel along directions of X, Z, and Y, and to turn the threaded grinding wheel in a Y-Z plane; an NC device for controlling the position of the threaded grinding wheel; and a rotary dressing device having a dressing tool which contacts the flanks of the threads of the threaded grinding wheel, while rotationally driven, to perform dressing, and wherein the NC device numerically controls the moving mechanism so as to adjust the positions in the directions of X and Z, and the turning position in the Y-Z plane of the threaded grinding wheel, while keeping contact of the dressing tool with the flanks of the threads of the threaded grinding wheel, in order to modify the wheel pressure angle of the threaded grinding wheel.

The invention discloses a paper cutting device, particularly relates to a hob type paper cutting device applied to a printer, and belongs to the field of computer communication technology. The hob type paper cutting device comprises a driving motor, a transmission mechanism, a rolling movable knife, a fixed knife, a holder, a paper pressing assembly, a guide support, a guide shaft, a guide plate, a position sensor, a tensioning support assembly, a control system and the like. The transmission mechanism transmits rotation movement of the driving motor to the rolling movable knife to perform automatic paper cutting. The hob type paper cutting device has the advantages that the hob type paper cutting device is modular in design manufacture, low in cost and convenient to maintain, assemble and disassemble; a pressure angle remains unchanged during paper cutting, so that paper is cut stably; a paper cutting assembly is simple in structure and good in paper cutting reliability.

The invention provides a dissymmetrical involute plastic gear, which belongs to the machine manufacturing field. The invention is characterized in that the technical proposal of the invention is that unsymmetrical involute profiles are adopted on both sides of the gear teeth of the plastic gear, the pressure angles on both sides of the gear teeth are unequal and the involute profile 4 of the larger pressure angle is taken as the working side; the tooth of the gear consists of a dedendum circle 1, the larger pressure angle involute profile 4 generated by a minor diameter base circle 2, the small pressure angle involute profile 6 generated by a major diameter base circle 3, a tooth top 5 and a transition curve 7. By comparing with the prior symmetrical involute plastic gear, the carrying capacity of the invention is improved, the service temperature is reduced and the service life is prolonged. Accordingly, the invention has wide application prospect and considerable economic benefits.

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.

The invention relates to a design method of a cylindrical cam profile of an oscillating follower. The method is characterized by comprising the following steps: introducing a coordinate expression of a 3D evolute of a displacement curve of the oscillating follower, putting forward a concept of a deviation angle, deducting the expression of the deviation angle according to a geometrical relation, and establishing a profile equation which is convenient for analyzing, designing and constructing the cylindrical cam of the oscillating follower; deducting an expression of a pressure angle according to the geometrical relation of the profile evolute, drawing a relation curve of a base radius R in relation to a maximum pressure angle alpha, and obtaining the minimum base radii which are corresponding to different allowable pressure angles; and programming an MATLAB program according to a known expression, namely, S=f(phi), 1, a and R, extracting coordinate values of the curve by MATLAB software after the operation of the program, pasting the coordinate values to AutoCAD software under a 'PLINE' command after processing, and then processing the coordinate values to 3D CAD software to obtain the profile. The solution process and the design process of the method are concise, visual, and easy to be controlled and practical, and have no design error.

The invention relates to a precise design and profile modification method for an asymmetric gear. The method comprises the following steps that S1, the tooth profile equation of a rack tool is obtained according to the structure of the rack tool; S2, coordinate transformation is carried out on the tooth profile equation of the rack tool according to the movement rule of the rack tool to obtain a rack tool equation under a gear coordinate system; S3, a meshing equation is obtained according to the meshing rule of the rack tool and the gear; S4, the tooth profile equation of the asymmetric gear is determined according to the rack tool equation and the meshing equation; S5, three-dimensional modeling is carried out according to tooth profile data. The profile modification method directly carrying out pressure angle profile modification on the rack tool is disclosed, the tool after the profile modification can directly carry out machining to obtain the formed gear having the involute modified, the gear machining efficiency is improved, and the obtained formed gear through the profile modification is simple and practical.

In a sprocket for use with a roller chain, a wear limit marker, having a different color from that of the base material of the sprocket, is provided on side surface of a sprocket tooth adjacent to a keyway. The wear limit marker is disposed on an imaginary line extending in the direction of the pressure angle, and is located in a hole or groove provided in a side surface of the sprocket tooth. The marker makes it possible to determine easily and reliably whether or not wear at the location at which wear of a sprocket tooth proceeds most rapidly is within a predetermined limit, and the location of the marker makes it possible to evaluate wear conditions even when the sprocket is installed in a machine.

The invention relates to a dual-pressure angle involute helical tooth externally-meshed cylindrical gear, and belongs to the technical field of gears. In the conventional involute helical tooth externally-meshed cylindrical gear, pressure angles at reference circles on two sides of involutes on the driving side and the driven side are equal to each other, but in the dual-pressure angle involute helical tooth externally-meshed cylindrical gear, a large pressure angle is formed at a reference circle of an involute on the driving side, and a small pressure angle is formed at a reference circle of an involute on the driven side, so the performance of the gear can be improved due to an asymmetrical design. A tooth profile on the end face of the gear comprises the involute (1) on the driving side, a tooth root transition curve (2) on the driving side, the involute (3) on the driven side, a tooth root transition curve (4) on the driven side, a tooth crest circular arc (5) and a tooth root circular arc (6); and the tooth profile on the end face moves along a spiral line to form the final dual-pressure angle involute helical tooth externally-meshed cylindrical gear.

The invention discloses a cam analyzer. The cam analyzer comprises a frame, a main transmission part, a fixed disc, a translation plate, a synchronous tensioning mechanism, an eccentric mechanism, a follower mechanism, a pressure angle measuring mechanism and a contact head. According to the invention, almost all knowledge points related with a cam are covered. A motion curve of the formed cam can be drawn; the corresponding cam can be drawn from a follower displacement graph; and the pressure angle of each point on the contour of the cam can be measured, and the size and the corresponding position of the maximum pressure angle can be found. During drawing of the follower displacement graph, the shape of the head portion of a follower can be converted, the motion curve map of cams in any shapes can be drawn, and such parameters as a cam turn angle, a basic circle dimension, a return travel angle, a travel angle, a farthest dwell angle, a nearest dwell angle and the like can be effectively detected, the bias distance of the follower can be changed, and cam motion graphs under the condition of different bias can be drawn. The apparatus greatly deepens students' understanding of the cams, facilitates teaching and improves the teaching quality.

The invention belongs to the technical field of bevel gear design, and particularly relates to a dot-line engaged bevel gear pair high in bearing capability and low in vibration. The dot-line engagedbevel gear pair high in bearing capability and low in vibration comprises a first bevel gear and a second bevel gear which are engaged with each other; the tooth number of the first bevel gear and thetooth number of the second bevel gear are taken as z1 and z2 correspondingly, the normal module of the first bevel gear and the normal module of the second bevel gear are taken as m<n1> and m<n2> correspondingly, the normal pressure angle of the first bevel gear and the normal pressure angle of the second bevel gear are taken as alpha<n1> and alpha <n2>, and the reference circle spiral angle of the first bevel gear and the reference circle spiral angle of the second bevel gear are taken as beta1 and beta2 correspondingly, wherein z1 and z2 meet the transmission ratio requirement and the convenient machining principle, and the values of m<n1> and m<n2> are selected in reference to the bevel gear handbook or customized according to needs; the values of alpha<n1> and alpha<n2> are selected according to transmission requirements, following relations are met, A), when z1 is smaller than z2, alpha<n1> is larger than alpha<n2>, alpha<n2> is larger than 20 degrees, and m<n1> is larger than m<n2>; B), when z1 is larger than z2, alpha<n2> is larger than alpha<n1>, alpha<n1> is larger than 20 degrees, and m<n2> is larger than m<n1>; the values of beta1 and beta2 are selected according to work needs, meanwhile, beta1 is equal to +/-beta2, '-' is taken for outer meshing, and '+'is taken for inner meshing. The provided dot-line engaged bevel gear pair combines the beneficial effects of dot-line engaged bevel gear and bevel gear joint outer meshing transmission at the same time and has the beneficial effects of being low in vibration, low in noise, large in strength and long in service life.

The invention relates to a water saving method for a rotary water sprayer with a wide range. The method is characterized by comprising a rotary water sprayer (59), a spraying head of the rotary water sprayer is rotary, and the heights from bottom to top of the groove bottoms of a right water spraying groove and a left water spraying groove in water spraying grooves of the rotary water sprayer are different to form the rotary water sprayer with the wide range. Arc grooves of the rotary water sprayer are respectively contour line grooves of which the parabolas are smoothly connected in a central arc equation manner and the cross sections are in wing shapes, the heights of the two groove bottoms are different, and the distance between two water throwing grooves is different, so that the rotary water spraying with axial flow and wide range is convenient. Function curves are adopted in multiple positions, so that the product quality is improved; an inner wall which is provided with a plurality of through holes and is arranged at the side part of a spraying head cap adopts a cube curve with the function of a buffering curve in the middles of a straight passage and a circular arc-shaped water passage, and the impact is alleviated when water flow turns; a rib is arranged between every two through holes, the rib is in an equal angle spiral shape, i.e. a logarithmic spiral shape, and the water can be uniformly sprayed because pressure angles are the same in any place; the batched quality of the product is further improved by the spraying head cap with a cube curve water passage and the equal angles spiral rib and a spraying head seat with a hyperbolic curve pipeline or a logarithmic spiral pipeline.

The number of teeth is set to 4n+2 (n is a natural number), both the ends on a long axis are set to be teeth grooves, both the ends on a short axis are set to be tips, a pitch curve is set to be, for example, an ellipse, and tooth marks 31-37, 41-47 are set to be basic tooth mark curves. With the tooth mark curve, the engagement teeth surface is set to be an involute curve, a non-engagement tooth surface is set to be a cycloid curve, and the tool pressure angle of each tooth mark is set by an undercut limit and a point limit. The non-circular gears 30, 50 bury the recess between two tooth marks, holding the tooth space located at both the ends on the long axis, based on the basic tooth mark curve, and have a shape, where the tooth section including the tip at both the ends on the short axis are scraped off, and the number of teeth completed is finally set to 4n-2. Accordingly, it is able to obtain a non-circular gear that reduces the change in an engagement pressure angle, is advantageous for setting the tool pressure angle of an engagement teeth surface, can reduce the number of teeth without forming an overhang section, and can fully secure the sealing performance with the inner wall of a casing to be installed.

The invention discloses a design method of a high-order modified eccentric circular gear and a non-circular gear pair conjugated with the high-order modified circular gear. There is no literature report on design and application research on a high-order modified eccentric circle-non-circular gear pair so far. The design method specifically comprises the following steps that firstly, a pitch curve equation of a high-order modified eccentric circle gear and a non-circular gear pair conjugated with the high-order modified eccentric circle gear is established, and a center distance is calculated through the numerical method; secondly, the concavity and convexity of a pitch curve are verified, the maximum modulus under the situation that undercutting is not carried out when a gear is machined through the gear shaping method is obtained, the pressure angle change range is calculated, the maximum pressure angle value is verified, and the contact ratio when the high-order modified eccentric circle gear and the non-circular gear pair conjugated with the high-order modified eccentric circle gear are meshed is calculated. According to the design method, a whole set of thorough design theoretical basis is provided for the high-order modified eccentric circle gear and the non-circular gear pair conjugated with the high-order modified eccentric circle gear in actual application, and the using and popularizing of the high-order modified eccentric circle gear and the non-circular gear pair conjugated with the high-order modified eccentric circle gear are promoted.

Electric power steering apparatus includes an electric motor for producing steering assist torque corresponding to steering torque applied to a steering system, and a worm gear mechanism for transmitting the steering assist torque to the steering system. The worm of the worm gear mechanism has a pressure angle greater than a pressure angle of the worm wheel, so as to reduce an actual meshing pitch circle diameter of the worm in the worm gear mechanism.

The invention discloses a variable pressure angle cam contour line design method applicable to sudden variable load. R1 refers to the radius of a base circle omicron, R2 refers to the farthest dwell arc radius, AB arc refers to a cam contour line with the radius of R3, and alpha refers to a theoretical working curve pressure angle. When the normal values R1 and R2 are given, a graph of relation between a lift range h and the pressure angle alpha can be determined under different R3 values. An optimal arc radius value R3 corresponding to the pressure angle alpha changed along with the lift range h under sudden variable load can be found through the graph. The variable pressure angle cam contour line design method applicable to sudden variable load has the advantages that the pressure angle is extremely small in an open stage of a main valve core during opening of a cam and matched with characteristics of loads, and additional force applied to a top rod can be decreased.