Showing papers on "Pressure angle published in 1987"

Cycloidal equidistant curved gear transmission mechanism and its device

Abstract: This invention involves a gear transmission mechanism and its device which incorporate double cycloidal equidistant conjugated gear mechanisms and devices, featuring in that a whole branch cyclic cycloidal equidistant curve at a side of the center of curvature of that cycloid is applied with the value of equidistance equal to or smaller than the radius of the rolling circle as the original tooth profile and thus conjugated mutually enveloping cycloidal equidistant curved gear mechanisms with one-tooth-difference, zero-tooth-difference or multi-tooth-difference can be made according to the requirement. Motor pumps and reducers made according to these mechanisms have the advantages of smaller sliding coefficient, smaller pressure angle, greater speed ratio range, lower noise, better strength, higher efficiency, more convenience in machining and lower cost. Therefore these mechanisms can be used to effectively replace the cycloidal lantern gearing with promising development of novel gear transmissions.

Fluid flow speed measuring apparatus

Abstract: A fluid flow speed measuring apparatus comprising a first pipe having an opening exposed into a fluid to be measured, a direction of the opening having an angle larger than a critical negative pressure angle, a second pipe having an opening exposed into the fluid to be measured, a direction of the opening of the second pipe having an angle larger than the critical negative pressure angle and at least one of conditions such as a diameter, a direction, and the number of the openings for determining a magnitude of the negative pressure being different from that of the opening of the first pipe, negative pressure difference detector for detecting a difference between negative pressures acting on the openings of the first and second pipes, and device for calculating a flow speed of the fluid to be measured on the basis of an output from the negative pressure difference detector.

Deflection engagement type gear device

Abstract: (57) [Summary] (Modified) [Purpose] In a flexible meshing gear device having a cup-shaped flexible external gear, the cup-shaped flexible external gear and the rigid internal gear are also good in the entire tooth stripe direction. So that a good mesh is formed. [Structure] The rigid internal gear and the cup-shaped flexible external gear have the same reference pressure angle, and the rigid internal gear has a constant or variable dislocation shift tooth profile, and the cup-shaped flexible external gear is arranged along the axis. Then, a dislocation tooth profile is obtained in which dislocations are continuously dislocated according to a dislocation coefficient xf determined by the following equation. (Xf: shift coefficient of flexible external gear; Xc: shift coefficient of rigid internal gear, Zc: number of teeth of internal gear, k: coefficient indicating deflection of cross section of external gear at right angle to axis, n: internal gear 1/2 of the difference in the number of teeth of the external gear, R: reduction ratio of the flexible mesh type gear device, α 0 : Standard pressure angle, X: Auxiliary angle representing the tooth gap when there is no dislocation, φ: Auxiliary angle regarding the position of the contact point of the tooth profile, j: 1/2 of the root rim thickness of the external gear and the root Sum of bamboo shoots)

Cam Design and Manufacture

Abstract: 1. Cam and Follower Systems 2. Displacement Diagrams 3. Displacement Diagram Synthesis 4. Cam Profile Determination 5. Pressure Angle and Radius of Curvature 6. Circular Cams 7. Circular-arc and Straight-line Cams 8. Forces, Contact Stresses, and Materials 9. Methods of Cam Manufacture 10. Dynamics of Cam Mechanisms 11. Cam Mechanisms 12. Velocities, Accelerations, and Dynamic Forces in Linkages and Cam Mechanisms 13. Computer Programs for Analysis and Synthesis of Cam Mechanisms

Tooth system for a shaft-hub connection

Abstract: There is provided a tooth system for the static transmission of a torque between two machine components coaxially disposed in one another, e.g. a shaft and a hub, in which the tooth surfaces are straight and are designed with a very large pressure angle and with large tip and root fillet radii. The pressure angle of one component deviating slightly from that of the other component by half the torsion angle so as to overcome backlash. As a result, under load, the tooth surfaces abut over their entire surface. Also, the hubs can be produced with a smaller blanking indentation, in particular in the case of discs made of sheet metal, which increases the bearing capacity, and furthermore this can be done even more precisely, which results in an increase in centering precision and less noise generation during operation.

Device for driving rotary body

Abstract: A device for driving a rotary body which is required to make contact with another rotary body with an even pressure distribution along its length, e.g. a register roller installed in an electrophotographic machine for feeding a paper sheet, a developing roller applicable to a contact type developing system, or a doctor roller of a developing apparatus. A developing roller, or one of the rotary bodies, is movable in a single limited direction toward and away from a photoconductive element, or the other rotary body, which is fixed in place. A drive gear is meshed with a driven gear which is mounted on one end of a shaft of the developing roller, thereby transmitting torque to the developing roller. The drive gear is located in such a position that an angle between the direction of movement of the developing roller and a line extending through the axes of the drive and driven gears is defined upstream of that direction of movement with respect to the direction of rotation of the developing roller and substantially equal to the pressure angle between the drive and driven gears. The force imparted from the drive gear to the driven gear acts in a direction substantially perpendicular to the direction of movement of the developing roller.

Ignition timing control for internal combustion engine

Abstract: A device for ascertaining knock as well as the max. pressure-angle in an IC engine and, in partic. for controlling the ignition time point, includes a pressure sensor (21) adjacent to combustion chamber, a crank-angle sensor (32), a signal generator circuit (20) connected to the pressure sensor (12), and an evaluating device (30) connected to the signal generation circuit (20) and to the crank-angle sensor 932) in order to determine the max. pressure angle at which the cylinder pressure is maximal, at which point the generator circuit (20) provides a first signal pulse when the output signal from the pressure sensor (12) attains a first max. value. A filter device (16) is connected into the circuit in order to simultaneously ascertain knock and the max. pressure-angle between the pressure sensor (12) and the signal generator circuit (20) and its output signal is compared, via a comparison element, with a reference value in order to provide a signal pulse when the proportion between the output signal (or the difference signal) and the reference value turns or reverses in a given direction. The evaluation device counts the number of signal pulses and decides that knock has occurred, when the number counted exceeds a given figure.

Screw and nut device for taking up clearance

Abstract: Device comprising a screw (6) and a nut (8) subjected to an axial force which alternates in opposite directions, the thread (7) of the screw having a given helix angle and a given pressure angle which are so chosen that, in a first direction, termed reversible direction, the screw (6) is capable, under the axial thrust exerted in this direction by a spring (20), of effecting a translation and a rotation in the nut (8), and that, in a second direction, termed irreversible direction, opposed to the first direction, the screw undergoing an axial thrust in this second direction by a push-member (9), can effect neither a translation nor a rotation in the nut. This assembly may be applied to the automatic taking up of play of systems subjected to alternating longitudinal forces, such as shafts of electric motors or cable controls.

Cycloidal equidistance curve gearing and its devices

Abstract: This invention involves a gear transmission mechanism and its device which incorporate double cycloidal equidistant conjugated gear mechanisms and devices, featuring in that a whole branch cyclic cycloidal equidistant curve at a side of the center of curvature of that cycloid is applied with the value of equidistance equal to or smaller than the radius (r) of the rolling circle (1) as the original tooth profile and thus conjugated mutually enveloping cycloidal equidistant curved gear mechanisms with one-tooth-difference, zero-tooth-difference or multi-tooth-difference can be made according to the requirement. Motor pumps and reducers made according to these mechanisms have the advantages of smaller sliding coefficient, smaller pressure angle, greater speed ratio range, lower noise, better strength, higher efficiency, more convenience in machining and lower cost. Therefore these mechanisms can be used to effectively replace the cycloidal lantern gearing with promising development of novel gear transmissions.

Toothing and gears made therewith

Abstract: A tooth according to the invention is such that its flank (foot flank) (1B) situated inside the not entirely circular pitch curve (PA) follows an involute of a circle determined by a pressure angle (p), and has a face (2B) outside the pitch curve such that its current point (M) is determined by the intersection of the flank (1A) of the co-operating tooth with the tangent to the circles defining the flank (1A) passing through the instantaneous point of contact (N) of the pitch curves (P'A, P'B). The pitch curves may be circular arcs, logarithmic spiral arcs, elliptical arcs, or a succession of such arcs around an open or a closed curve in order to form gearing. Some lengths of the pitch curves may have no teeth.

Corrected addendum wn gear

Abstract: PURPOSE:To improve handling by replacing a portion of a tooth end arched section of a referential rack tooth in a point contact WN gear with an involute curve thereby considerably relieving the sensibility of the portion near to the tooth tip against the central distance error. CONSTITUTION:With respect to the tooth profile of a referential rack in a point contact WN gear to be obtained through profile shifting while employing a referential rack having such tooth profile as concave/convex arches having same radius and intermediate lines connecting them are combined, the portion of the tooth end arched section near the tooth tip is replaced with an involute curve having curvature gradually reducing toward the tooth tip thus to perform correction. WN gear is a helical gear and the rack is also a helical rack thereby the referential rack tooth profile is defined on proper cross-section of referential rack. In other word, the arch (dashed line) from the points A, E at the tooth end (pressure angle alpham) to the tooth tip is replaced with an involute curve (solid line). The tooth profile for smaller pressure angle than (alpham), an arch and lines are combined.

Tooth thickness measuring tool for gear

Abstract: PURPOSE:To measure tooth thickness with high accuracy by forming a couple of rack teeth with a specific pressure angle on a gauge main body, fitting a dial gauge on the opposite side from them, and projecting the measuring element to a bottom groove part between both rack teeth CONSTITUTION:The rack teeth 2A and 2B which has the same pressure angle alphaas the pressure angle of a gear 11 to be measured are formed at one side part of the gauge main body 1 Their tooth surfaces 3A and 3B have their center parts 4 swelling in a horizontal sectional shape so as to improve the contacting between the gear 11 and tooth surfaces Further, a through hole 5 is formed in the center of the opposite part of the main body 1, the dial gauge 6 is fitted in the hole 5, and the measuring element 7 is projected into the bottom groove part 8 between the teeth 2A and 2B the measuring element 7, therefore, moves on a straight line running in the center of the gear 11 Thus, main body 1 and gear come into surface contact, so the tooth surfaces 3A and 3B hardly wear away and even if the pressing force of the gear 11 to the main body 1 varies depending upon a measuring person, there is a little influence upon the measuring element 7 and a high-accuracy measurement is taken

Tooth Profile of an Involute Gear

Abstract: In general, the tooth profile of a rack may be curved, and the profile angle \(\phi^{\rm A_r}\) would then vary from one point of the tooth to another We now consider a particular rack, in which the teeth are straight-sided This is the basic rack which we use to define the tooth shape of an involute gear The profile angle for this rack is constant, and the value of the constant will be represented by the symbol Φr, which is called the pressure angle of the basic rack Thus, for the basic rack used to define involute tooth profiles,

Dent removing device for gear

Abstract: PURPOSE:To enable a swollen part, generated by a hit flaw on a tooth surface, to be removed in a very short time, by removing at a time the swollen part in a work gear tooth end part by the first grinding gear while the swollen part in four end parts of both observe and reverse tooth surfaces by the second grinding gear. CONSTITUTION:A spindle 18 is forwardly rotated by a motor 30 rotating gears 17, 37, 21 to be meshed, simultaneously a swivel bed 23 is swiveled twisting by a swivel cylinder 28, and the second grinding gear 21 is swiveled twisting for the work gear 37. And the first grinding gear 17, having a tooth part of pressure angle larger than that of the work gear 37, grinds only a tooth end part of the work gear 37 to remove a swollen part in a short time. Simultaneously, the second grinding gear 21, whose tooth surface provides a hollow lead, grinds two parts A, B on an opposite angle of both obverse and reverse surfaces of the work gear 37, if the gear 21 swivels in one side, while two end parts C, D in the opposite side, if the gear 21 swivels in the other side, and swollen parts of the four end parts A-D in the both obverse and reverse surfaces can be ground at a time in a short length of time. The operation is repeated by reversely rotating the motor 30.

Effect of standard pressure angle on the bending fatigue strength of helical gears.

Abstract: This paper presents a study on the effect of standard pressure angle on the bending fatigue strength of helical gears. The root stresses of meshing helical gears with various pressure angles, helix angles and whole tooth depths were calculated by using the approximate equations for deflection and bending moment due to a concentrated load on gear teeth of full depth and long teeth with various pressure angles and Kubo and Umezawa's method. Bending fatigue tests were performed on helical gears of full depth teeth with various pressure angles and helix angles. On the basis of these results, the effects of pressure angle, helix angle, and whole tooth depth on the root stresses and bending fatigue strength of helical gears were clarified to a considerable extent.

Hob cutter for cutting involute gear.

Abstract: This invention relates to a hob cutter for cutting gears and more particularly to a hob cutter or rack cutter capable of simultaneously cutting and chamferring an involute gear. The hob cutter in accordance with the present invention is a hob or rack cutter for cutting and chamferring gears wherein a pressure angle alpha1 and module M of a rack tooth shape of a rack for cutting a first involute gear are respectively different from a nominal pressure angle alphao and module m but offer a so-called transfer rack tooth shape in order to provide limit values to a number of teeth vs. chamfer quantity characteristic curve and to minimize a change in a chamfer quantity. According to the present invention, it is possible to ordinarily chamfer almost all gears from gears having a small number of teeth to gears having a large number of teeth with one kind of hob cutter.

Paired bevel gears using the principle-positive sum of modifying coefficients

Abstract: The sum of modifying coefficients of the paired bevel gears is taken to be positive and the standard pitch cones are separated from the pitch cones after modifications. The operating pressure angle increases and the gear teeth can be machined with existing machine tools. The mechanism has more strength, longer service life, optimal radial and tangential modifying coefficients so that a new shape of gear teeth can be obtained and can be used for various working conditions with various design criteria.

Shuttle loom with low-pressure cam mechanism for inserting shuttle

Abstract: The utility model relates to a shuttle loom with low-pressure cam mechanisms for inserting shuttles, which adopts a low pressure angle cam and a drum rotor; the mould surface of the low pressure angle cam is in cylinder curve. The better inserting shuttle principle is approximate as-the fuller's grade x=a (sin omega t-bsin 5 omega t); the an in the principle is a rotor movement and the value is 30 mm to 50 mm; the b in the principle is a coefficient and the value is 0.02 to 0.08. Therefore, the traditional cams and rotors are replaced, so is the weft picking principle which is approximate as the sinusoid; thus the shuttle loom with low-pressure cam mechanisms for inserting shuttles obtains the effect of notable improvement of the stressing of each element, and small vibration and noise; the shuttle loom with low-pressure cam mechanisms for inserting shuttles also obtains the effect that the processing manufacturability of the cam is improved and the cam and the rotor are not easy to be worn and have a long service life.