Showing papers on "Pressure angle published in 1992"

Angle of attack sensor using inverted ratio of pressure differentials.

Abstract: An angle of attack sensor (10) is provided with ports (20, 21, 22, 23) for sensing flow angles in desired planes based upon differential pressure at the ports (20, 21 or 22, 23) when a reference axis of the sensor (10) changes relative to the flow stream. Impact pressure (qcm) is also measured, and the angle of attack is calculated by subtracting the pressures at the angle sensitive ports (20, 21 or 22, 23), and dividing by the measured impact pressure (qcm). At higher angles of attack, the denominator qcm approaches and passes through zero. It has been discovered that if the angle of attack ratio is inverted at some point when the denominator qcm approaches zero, the useable range of indication of angle of attack can be greatly extended.

Vehicle park lock mechanism

Abstract: In a vehicle park lock mechanism having a rotatable lock arm (5) for locking a gear (3) which is fixedly mounted on a transmission shaft (2), a pawl device integral with the lock arm is comprised of first and second locking pawls (6F, 6R) which are operable to engage the gear so as to prevent forward and backward directional rotations of the gear. The first and second pawls are arranged such that they may project into one and another toothe spaces (3b) of the gear which are spaced circumferentially of the gear with at least one tooth space therebetween. Gear having a relatively large pressure angle such as a transmission gear may satisfactorily be used as the gear for the lock mechanism.

A Measurement of Oil Film Pressure Distribution in Connecting Rod Bearing With Test Rig

Abstract: In designing an optimum connecting rod, it is necessary to determine the oil film pressure (OFP) distribution at the big end under the actual engine operating conditions because it is used as the boundary conditions in a structural analysis. Since it is very difficult to measure the OFP distribution, a bearing test rig has been developed to simulate the load of an operating engine. The measured data on the cap side of the connecting rod obtained with this test rig shows a lower maximum oil film pressure and a wider pressure angle than those on the rod side. Presented at the 46th Annual Meeting in Montreal, Quebec, Canada April 29–May 2, 1991

Effect of contact ratio on spur gear dynamic load

Abstract: A computer simulation is presented which shows how the gear contact ratio affects the dynamic load on a spur gear transmission The contact ratio can be affected by the tooth addendum, the pressure angle, the tooth size (diametral pitch), and the center distance The analysis presented was performed using the NASA gear dynamics code, DANST In the analysis, the contact ratio was varied over the range 120 to 240 by changing the length of the tooth addendum In order to simplify the analysis, other parameters related to contact ratio were held constant The contact ratio was found to have a significant influence on gear dynamics Over a wide range of operating speeds, a contact ratio close to 20 minimized dynamic load For low contact ratio gears (contact ratio less than 20), increasing the contact ratio reduced the gear dynamic load For high contact ratio gears (contact ratio = or greater than 20), the selection of contact ratio should take into consideration the intended operating speeds In general, high contact ratio gears minimized dynamic load better than low contact ratio gears

Tertiary negative-deviation flexing contact type gear drive of non-profile-shifted tooth profile

Abstract: In a cup-shaped flexing contact gear (1), both a rigid internal gear (2) and a flexible external gear (3) are made to be non-profile-shifted spur gears, an opening (3a) of the flexible external gear (3) is set in a state of negative deviation wherein a deflection of the opening is lower in value than a normal deflection; a moving locus is obtained through rack approximation of teeth of the external gear to the internal gear at respective sections of rotation of tooth trace of the flexible external gear (3), an envelope (e) is obtained by overlapping the moving locus on one of sections of rotation, another moving locus is obtained in a section of rotation at the end portion of tooth trace on the side of a diaphragm or in the vicinity of the outside of the end portion and is smoothly connected to the envelope to thereby obtain a composite curve (L). A curve (FE) is obtained by similarity transforming at a reduction ratio of 1/2 a portion from a starting point (A) of the envelope (e) to a terminating point (E) thereof corresponding to two times the working depth in the direction of the depth from an apex of a moving locus (l o) when deviation is 0, using the terminating point as an original point, and this curve is made to be each of main portions of convex tooth profiles at tooth faces of the both gears (2, 3). Further, a composite curve (MFE) including a straight line (MF) having a limited pressure angle (α M ) associated with a deflection value of the opening inserted in the vicinity of a datum point (M) of tooth profile and a transient curve smoothly connecting the straight line to the main portion of the convex tooth profile is made to be each of tooth profiles at the tooth faces of the both gears.

Maximum life spiral bevel reduction design

Abstract: Optimization is applied to the design of a spiral bevel gear reduction for maximum life at a given size A modified feasible directions search algorithm permits a wide variety of inequality constraints and exact design requirements to be met with low sensitivity to initial values Gear tooth bending strength and minimum contact ratio under load are included in the active constraints The optimal design of the spiral bevel gear reduction includes the selection of bearing and shaft proportions in addition to gear mesh parameters System life is maximized subject to a fixed back-cone distance of the spiral bevel gear set for a specified speed ratio, shaft angle, input torque, and power Significant parameters in the design are: the spiral angle, the pressure angle, the numbers of teeth on the pinion and gear, and the location and size of the four support bearings Interpolated polynomials expand the discrete bearing properties and proportions into continuous variables for gradient optimization After finding the continuous optimum, a designer can analyze near optimal designs for comparison and selection Design examples show the influence of the bearing lives on the gear parameters in the optimal configurations For a fixed back-cone distance, optimal designs with larger shaft angles have larger service lives

Tertiary negative-deflection flexing contact gears of non-profile-shifted tooth profile.

Abstract: In cup-shaped flexing contact gears (1), both a rigid internal gear (2) and a flexible external gear (3) are made to be non-profile-shifted spur gears, an opening (3a) of the flexible external gear (3) is set in a state of negative deflection lower in value than a normal deflection, a moving locus is obtained through rack approximation of teeth of the external gear to the internal gear at respective sections of rotating of tooth trace of the flexible external gear (3), another moving locus in a section of rotation at an end portion of tooth trace on the side of a diaphragm or in the vicinity of the outside of the end portion is smoothly connected to an envelope e &cir& - of the first moving locus, which is obtained by overlapping this moving locus on one of the sections of rotation, so that a composite curve L is obtained. A curve FE is obtained by subjecting to the conversion of similitude of 1/2 in the reduction ratio a portion from a starting point A of the envelope e &cir& - to a terminating point E corresponding to two times the working depth in the direction of the depth from an apex of the moving locus lo when the deflection is 0, using the terminating point as an original point, this curve FE is made to be each of main portions of convex tooth profiles at the tooth faces of the both gears 2 and 3, and, a composite curve MFE includes a straight line MF having a limited pressure angle alpha M associated with a deflection value of an opening inserted in the vicinity of a datum point M of tooth profile and a transient curve smoothly connecting the above-mentioned straight line to the main portion of the convex tooth profile, and this composite curve MFE is made to be each of tooth profiles at the tooth faces of the both gears.

Tooth geometry for fan shaft spline coupling

Abstract: There is provided by the present invention a fan shaft coupling for a gas turbine engine having an increased loading capacity and a tooth geometry therefor. The tooth geometry comprises a tooth profile including an involute form having a thirty degree pressure angle [B] and a compound curvature root fillet.

Kinematic Synthesis and Analysis of the Rack and Pinion Multi-Purpose Mechanism

Abstract: The general procedure for synthesizing the rack and pinion mechanism up to seven precision conditions is developed. To illustrate the method, the mechanism has been synthesized in closed form for three precision conditions of path generation, two positions of function generation, and a velocity condition at one of the precision points. This mechanism has a number of advantages over conventional four bar mechanisms. First, since the rack is always tangent to the pinion, the transmission angle is always 90 deg minus the pressure angle of the rack. Second, with both translation and rotation of the rack occurring, multiple outputs are available. Other advantages include the generation of monotonic functions for a wide variety of motion and nonmonotonic functions for a full range of motion as well as nonlinear amplified motions. In this work the mechanism is made to satisfy a number of practical design requirements such as completely rotatable input crank and others. By including the velocity specification, the designer has considerably more control of the output motion. The method of solution developed in this work uses the complex number method of mechanism synthesis. A numerical example is included.

Drive device of tuning body

Abstract: PURPOSE:To increase exchangeability and degree of design freedom for a mounting device by contacting a second movable turning body with a first turning body which is fixed uniformly. CONSTITUTION:An angle theta is constituted by a line (a) which connects each center of a follow-up gear (first gear) 21 which is mounted on a developing roller (second turning body) and a drive gear (second gear) 22 which is fixed on a mounting device which transmits drive force to the follow-up gear 21 and a line (b) which connects each center of the follow-up gear 21 and an idler gear (third gear) to which drive force is transmitted from the follow-up gear 21. Pressure angle of each gear is alpha and set to theta, 2alpha. Drive force F1 which is generated at engaging position of each gear and reaction force F2 are opposed and canceled out, and the developing roller contacts with a photosensitive drum (first turning body) uniformly. An idler gear 23 is positioned on the downstream side than the drive gear 22 for the rotation direction c of the follow-up gear 21 so that the drive gear 22 does not become an obstacle in the direction of pull-out of a unit including the developing roller.

Designing Joints and Driveshafts

Abstract: The useful life of a driveshaft is determined mainly by the joints. For this reason the other component parts will not be discussed here; they can in any case be designed using the general principles of strength of materials.

Meter for pressure angle of operating point of embossing machine

Abstract: During the operation of the existing cotton gin, an important factor affecting the ginning yield and quality is a pressure angle on the operating site of the cotton gin The angle is required in 50 to 70 DEG in theory, but at present in China no accurate measuring instrument can meet such requirement The utility model provides a measurer with high precision and convenient operation, which can directly measure the pressure angle on the operating point of the cotton gin and which comprises a sector plate, a main scale, a vernier sheet, a convex sector plate, a brake, fastening screws, a fine adjustment hand wheel and a sector gear plate While in use, the sector plate and the convex sector plate are respectively attached tightly to the saw blade and the rib surface of the cotton gin, and then a measured result can be gained

Fan shaft-spline joint

Abstract: PURPOSE: To lighten an engine by constituting a fan driving shaft of the gas turbine engine with inner and outer shafts interconnected through a spline coupling, and constituting the spline coupling with inner and outer splines having a tooth in an involute form having a specific pressure angle. CONSTITUTION: A gas turbine engine has a fan driving shaft 38 extending through a rotor disc of a compressor rotor means, and a front fan disc is mounted to the front end of the shaft 38. The fan driving shaft 38 is constituted with a low pressure turbine shaft 60 and a front fan shaft 62 interconnected through a spline coupling 64, and the spline coupling 64 is constituted with inner and outer splines 65, 66. A plurality of spline teeth 80 defining a portion of an inner spline 54 are engaged with a plurality of outer splines 82 defining a portion of the outer spline 66, and the teeth 80 are formed so as to have a tooth profile 86 including an involute form having a pressure angle β equal to 30 deg..

Numerical simulation for the effect of sound velocity anisotropy on shift of probe index and beam angle of ultrasonic angle probes

Abstract: The probe index and beam angle of angle probes are very important characteristics in ultrasonic angle beam examination, which are recommended to be measured by using a standard specimen, STB-A1 (IIW-l/ISO-2400). However, it has not been made clear how sound velocity anisotropy, if it exists, affects those characteristics in the STBs or in similar specimens. In order to clarify the problem, an analytical study was carried out by the numerical simulation method for ultrasonic angle beam examination, which had been developed by the author. In consequence, the following results were obtained. (1) Large negative shifts of the probe position, which mean positive shift of the probe index, are observed for the beam angles of angle probe larger than 45 degrees when the maximum sound velocity is at 45 degrees to the scanning surface of STBs. There exist negative shifts of probe index at the beam angles smaller than 45 degrees. The reverse phenomena take place if the maximum sound velocity occur at 0 and 90...

Check gage for gear measuring apparatus

Abstract: PURPOSE:To test the accuracy of a gear measuring apparatus by tracing a reference involute curve with a probe which is in contact with the arc surface of a reference gage by rotation and linear motion. CONSTITUTION:An internal gear IG is fixed and arranged on a surface plate 1. The turning center of a gear measuring device 100 is made to agree with the virtual turning center of the inner gear IG. Then, a probe 9a is directed to the approximately central part of the gear width of the gear with a z-axis moving device 6. Then, the probe 9a of a displacement gage 9 is adjusted so that the probe 9a is positioned at the above described initial-coordinate values of Xg and Yg which are determined by a pitch-circle diameter Ep and a pressure angle alpha with an X-axis moving device 4 and a Y-axis moving device 5. A turning table 3 is turned, and the probe 9a is brought into contact with a point on the pitch circle of the inner gear IG. At this time, the probe 9a is displaced so that the displacement sensor 9 is located at the approximately central position of the measuring range. The display value of the display which is not shown in the figure is set at zero. Then, a measuring command is imparted from a keyboard and the like. The measuring command control the moving amount of the displacement sensor 9 in the X direction with the X-axis moving device 4 and the turning amount of the displacement center 9 with the turning table 3.