JP2008019964A - Internal force measuring device for uniform motion universal joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an internal force measuring device to be able to exactly measure the internal force of a fixed uniform motion universal joint. <P>SOLUTION: The internal force measuring device 1 is provided with a sensor 3 to measure the track load acting on a track groove of an outer ring 2 from a ball 6 by detecting a displacement amount of a measuring part 3a displaceably installed in the torque transmitting direction of the ball 6 when the uniform motion universal joint comprising the outer ring 2, an internal ring 5, a ball 6, and a gage 7 works. A measuring part 3a of the sensor 3 has two side wall surfaces 3a1, 3a2 guided along a guide 2a installed in the outer ring 2. Out of these, at least a side wall surface 3a1 at a side approaching an outer spherical surface 7a of the gage 7 is formed in parallel with an axis line 9 extending in the torque transmitting direction of the ball 6. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an internal force measuring device for a constant velocity universal joint that is used for measuring an internal force acting on the inside of the constant velocity universal joint when the constant velocity universal joint is operated.

  Constant velocity universal joints are used, for example, in power transmission mechanisms of automobiles and various industrial machines, and output rotational torque from the input shaft using the input shaft and output shaft provided so that the crossing angle between them can be changed. It is connected so that it can be transmitted to the shaft at a constant speed. This constant velocity universal joint is a so-called fixed type constant velocity universal joint that allows only the operating angular displacement between the two shafts of the input shaft and the output shaft, and so-called sliding that allows axial displacement in addition to the operating angular displacement. It is roughly classified into a constant velocity universal joint.

  By the way, the above constant velocity universal joint includes, as main constituent members, for example, an outer ring as an outer joint member having a track groove, and an inner ring as an inner joint member having a track groove that makes a pair with the track groove of the outer ring, A plurality of balls arranged on a track formed by cooperation of both track grooves of the outer ring and the inner ring, and a cage for holding the balls are provided. At the design stage of this constant velocity universal joint, the force acting on the inside of the joint during operation (so-called internal force) is derived by numerical analysis etc., and then for the purpose of verifying the validity of the data obtained by numerical analysis etc. Experiments that assume actual operating conditions are usually conducted. Examples of the internal force to be analyzed and verified include a track load acting on the track groove of the outer ring from the ball, and an outer ring inner surface load acting on the inner diameter surface of the outer ring from the cage, and are proposed to perform these measurements. In addition, an internal force measuring device having the following configuration is known.

  FIG. 3 shows an outline of a known internal force measuring device, which is used for measuring internal force of a sliding type constant velocity universal joint, more precisely, an angular contact type double offset constant velocity universal joint (DOJ). The outline of the internal force measuring device to be used is shown. The internal force measuring device 100 shown in the figure mainly includes a constant velocity universal joint composed of an outer ring 111 and a joint internal component disposed on the inner diameter side of the outer ring 111, and two circumferential directions of the outer ring 111. The first sensor 130 and the second sensor 140 are disposed in a sensor mounting portion provided. Each of the sensors 130 and 140 is connected to a data processing system (not shown) including a plotter. The joint internal part includes an inner ring 112, a ball 113, and a cage 114, and a shaft 115 is connected to an inner diameter surface of the inner ring 112 via a torque transmission means.

  The first sensor 130 is used for measuring the track load, and a measuring portion 130a that can be displaced in the torque transmission direction of the ball 113 in accordance with the action of the track load is provided at the tip of the first sensor 130. The measuring unit 130 a is displaced along a guide unit provided at a location adjacent to the ball 113 among sensor mounting units provided on the outer ring 111. The first sensor 130 is configured so that one end surface of the measurement unit 130a is in contact with the ball 113 when a track load is applied, or one end surface of the measurement unit 130a is in contact with the ball 113 in advance. It is arranged.

  On the other hand, the second sensor 140 is used for measuring the inner ring surface load of the outer ring, and at the tip thereof, the measurement is displaceable in a direction perpendicular to the axis of the shaft 115 in accordance with the action of the outer ring inner surface load. Is provided. The measurement part of the second sensor 140 is displaced along a guide part provided at a location adjacent to the cage 114 among sensor attachment parts provided on the outer ring 111 as described above. The second sensor 140 is configured such that one end surface of the measurement unit is in contact with the cage 114 when the outer ring inner surface load is applied, or one end surface of the measurement unit is in contact with the cage 114 in advance. It is arranged.

  The internal force measuring apparatus 100 is generally configured as described above. When the constant velocity universal joint is operated (the shaft 115 is rotated), a track load acts on the track groove of the outer ring 111 from the ball 113. When the track load is applied (when the ball 113 is displaced to the outer diameter side), the measurement unit 130a of the first sensor 130 is pressed by the ball 113, and the measurement unit 130a is displaced in the torque transmission direction of the ball 113. At the same time, when an outer ring inner surface load is applied from the cage 114 to the inner surface of the outer ring 111 (when the cage 114 is displaced to the outer diameter side), the measurement unit of the second sensor 140 is pressed by the cage 114, and the measurement unit Is displaced in a direction perpendicular to the axis of the shaft 115. And each load derived | led-out by detecting the displacement amount of the measurement part of each sensor 130,140 is recorded by a data processing system (refer nonpatent literature 1 above).

An internal force measuring device for an angular contact type tripod type constant velocity universal joint obtained by changing a part of the above-described internal force measuring device is also known (see Non-Patent Document 2).
Transactions of the Japan Society of Mechanical Engineers (edition C) Volume 69, No. 678 (2003), p487-495 Proceedings of Annual Meeting 2003 of the Japan Society of Mechanical Engineers 4 p155-156

  As described above, any known internal force measuring device is an internal force measuring device for an angular contact type sliding constant velocity universal joint. It is desirable to measure the internal force at the design stage not only in the sliding type constant velocity universal joint but also in the fixed type constant velocity universal joint. However, an internal force measuring device for the fixed type constant velocity universal joint has not yet been proposed. It has not reached. Therefore, in order to measure the internal force of the fixed type constant velocity universal joint, the present inventor decided to use the internal force measuring device 100 described above as the internal force measuring device of the fixed type constant velocity universal joint as it is. . A configuration example in that case is shown in FIG. In the figure, in order to measure the track load at two contact points (torque transmission points) of the track groove of the ball 113 and the outer ring 111, the first sensors 130 are provided at two locations in the circumferential direction.

  As is apparent from the illustrated example, the conventionally used first sensor 130 for measuring the track load is an outer wall surface 130a1 on the side closer to the outer diameter surface of the cage 114, of the outer wall surface of the measurement unit 130a. Has a tapered shape. Therefore, an acute angle portion with an angle α is formed between the measurement unit outer wall surface 130 a 1 of the first sensor 130 and the outer diameter surface 114 a of the adjacent cage 114. In the fixed type constant velocity universal joint, since the outer diameter surface (outer spherical surface) of the cage 114 on which the internal force acts is adjacent to the track groove of the outer ring 111, the first angle is formed when such an acute angle portion is formed. The stress from the adjacent cage 114 also acts on the measurement unit 130a of the sensor 130. Therefore, deformation (elastic deformation) more than the original occurs in the measurement unit 130a of the first sensor 130, and as a result, the track load that should originally act on the measurement unit 130a escapes (becomes smaller). From the above, even if the configuration of the internal force measuring device 100 for the sliding type constant velocity universal joint is used as it is as the internal force measuring device 110 of the fixed type constant velocity universal joint, the track load to be measured is accurately measured. It turns out that you can't.

  An object of the present invention is to provide an internal force measuring device capable of accurately measuring an internal force generated inside a joint in an operating state of a constant velocity universal joint, particularly a fixed type constant velocity universal joint.

  In order to achieve the above object, according to the present invention, an outer joint member having one end opened and having a track groove on the inner diameter surface and an inner joint member having a track groove paired with the track groove of the outer joint member on the outer diameter surface are provided. A plurality of balls arranged on a track formed by cooperation of both track grooves of the outer joint member and the inner joint member, and a cage that is disposed between the outer joint member and the inner joint member and holds the balls Of the internal force acting on the inside of the constant velocity universal joint, and the measurement of the track load acting on the track groove of the outer joint member from the ball is displaced in the torque transmission direction of the ball. In an internal force measuring device for a constant velocity universal joint provided with a sensor for detecting a displacement amount of a measuring section that can be provided, the measuring section is proposed along a guide section provided inside the outer joint member. Two side wall surfaces facing each other, and of the two side wall surfaces, the side wall surface closer to the outer diameter surface of the cage is formed in parallel with an axis extending in the torque transmission direction of the ball. An internal force measuring device for a constant velocity universal joint is provided. Note that the term “parallel” as used above includes the case where it is not slightly parallel.

  As described above, the internal force measuring device for a constant velocity universal joint according to the present invention is configured so that the measuring portion provided in the sensor is guided along two guide sides provided along the guide portion provided in the outer joint member. It has a wall surface, and of these two side surfaces, the side wall surface on the side close to the outer diameter surface of the cage is formed in parallel with an axis extending in the torque transmission direction of the ball. According to such a configuration, the angle between the side wall surface of the measurement unit and the outer diameter surface of the cage can be increased as compared with the conventional configuration. Therefore, the stress from the adjacent cage is less likely to act on the measurement part of the sensor, and as a result, the measurement part of the sensor can react accurately only to the track load and can be accurately displaced in the direction of torque transmission of the ball. Therefore, with the above configuration, the track load can be measured more accurately than the conventional configuration shown in FIG. Further, in the conventional configuration, a new stress concentration portion is generated due to the stress from the cage acting on the measurement portion, which may lead to a decrease in the durable life of the sensor, particularly the measurement portion. On the other hand, if it is the structure of the said invention, generation | occurrence | production of this new stress concentration part can be prevented, and the durable fall etc. of a durable life can be avoided.

  The internal force measuring device for a constant velocity universal joint further includes a load acting on the outer joint member from the cage (outer joint inner diameter surface load) among internal forces acting on the constant velocity universal joint in an operating state. ) Can be provided.

  For the reason described above, the internal force measuring device having the above configuration is, for example, the inside of a so-called Zepper type fixed constant velocity universal joint in which the inner surface of the outer joint member and the outer surface of the inner joint member are formed by spherical surfaces. It can be suitably used for force measurement. In the internal force measuring device having the above configuration, for example, the track groove of the outer joint member has a linear portion parallel to the axis toward the opening side of the outer joint member, and the track groove of the inner joint member is It can be suitably used for measuring the internal force of a so-called undercut-free fixed type constant velocity universal joint having a linear portion parallel to the axis toward the opposite opening side of the joint member.

  Moreover, the internal force measuring device according to the present invention includes a constant velocity universal joint in which balls are equally distributed at six locations in the circumferential direction, a type in which balls are equally distributed at eight locations in the circumferential direction, and the like. It can also be suitably used for measuring the internal force of a quick universal joint.

  As described above, according to the present invention, it is possible to provide an internal force measuring device capable of accurately measuring the internal force of a constant velocity universal joint, particularly the internal force of a fixed type constant velocity universal joint.

  Hereinafter, an internal force measuring device according to the present invention will be described with reference to the drawings.

  FIG. 1 shows an internal force measuring apparatus 1 according to the present invention, which is used for measuring internal force of a fixed type constant velocity universal joint, more precisely, a so-called angular contact type Rzeppa constant velocity universal joint. is there. The internal force measuring device 1 shown in FIG. 1 includes an outer ring 2 as an outer joint member having a plurality of track grooves on an inner spherical surface, a joint internal component disposed on the inner diameter side of the outer ring 2, and a circumferential direction 3 of the outer ring 2. The first sensor 3, 3 and the second sensor 4 are arranged in a sensor mounting portion provided by cutting out a portion. A data processing system (not shown) composed of a plotter or the like is connected to the first sensor 3, 3 and the second sensor 4. The joint internal parts described above cooperate with the inner ring 5 as an inner joint member having a plurality of track grooves paired with the track grooves of the outer ring 2 on the outer spherical surface, and the track grooves of the outer ring 2 and the track grooves of the inner ring 5. A plurality of (six in the illustrated example) balls 6 disposed on the ball track formed in the above, and a cage 7 disposed between the outer ring 2 and the inner ring 5 and having a ball pocket for accommodating the balls 6; The shaft 8 is connected to the inner periphery of the inner ring 5 via torque transmission means such as serrations and splines.

  The first sensors 3 and 3 are for measuring the track load acting on the track groove of the outer ring 2 from the ball 6 in the operating state of the joint, and are arranged on the outer diameter side of the different balls 6 respectively. It is fixed to the outer ring 2 with a screw hole provided in the base portion. The first sensor 3 disposed on the left side in the figure is for measuring the track load at one of the two contact points (torque transmission point) between the ball 6 and the track groove of the outer ring 2. The first sensor 3 disposed on the right side in the drawing is for measuring the track load at the contact point on the other side of the two contact points between the ball 6 and the track groove of the outer ring 2. belongs to.

  At the tip of the first sensors 3 and 3, when the ball 6 is displaced to the outer diameter side due to the action of the track load, a measuring unit that can be displaced in the torque transmission direction of the ball 6 following the displacement. 3a is provided. The measurement unit 3 a is connected to a piezoelectric element provided on the base part side (outer diameter side) of the sensor 3. The piezoelectric element enables the detected displacement amount to be converted into an electric signal. The first sensor 3 is arranged such that the end surface of the measuring unit 3a is in contact with the ball 6 when a track load is applied, or the end surface of the measuring unit 3a is in contact with the ball 6 in advance. Yes.

  As shown in FIGS. 1 and 2, the measurement unit 3 a includes two opposing side wall surfaces 3 a 1 guided along a guide unit 2 a provided in a region adjacent to the ball 6 in the sensor mounting portion of the outer ring 2. 3a2. Of the two side wall surfaces 3 a 1 and 3 a 2, the side wall surface 3 a 1 closer to the outer spherical surface 7 a of the cage 7 is formed in parallel with the axis 9 extending in the torque transmission direction of the ball 6. By the way, the direction of displacement of the measurement unit 3a is very important in accurately measuring the track load. Therefore, it is desirable that the first sensor 3 is disposed so that the displacement direction of the end surface on the contact side with the ball 6 of the measuring unit 3a is perpendicular to the axis 9 extending in the torque transmission direction of the ball 6. .

  The second sensor 4 is for measuring the outer ring inner spherical load acting on the inner spherical surface of the outer ring 2 from the outer spherical surface 7 a of the cage 7 in the operating state of the joint, and is disposed on the outer diameter side of the cage 7. For example, it is screwed and fixed to the outer ring 2 by a screw hole provided in the base portion. The second sensor 4 is arranged so that the displacement direction of the measuring portion coincides with an axis extending in the contact angle direction between the outer spherical surface 7 a of the cage 7 and the inner spherical surface of the outer ring 2. The measurement part of the second sensor 4 is also connected to a piezoelectric element provided on the base part side (outer diameter side) of the sensor 4, similarly to the measurement part 3 a of the first sensor 3. The second sensor 4 is arranged such that the end face of the measuring portion is in contact with the cage 7 when the outer ring inner surface load is applied, or the end face of the measuring portion is in contact with the cage 7 in advance. Has been.

  In the internal force measuring device 1 configured as described above, when the joint is put into an operating state (when the shaft 8 is rotated), a track load acts on the track groove of the outer ring 2 from the ball 6 and the ball 6 has an outer diameter. When it is displaced to the side, the side wall surface of the measurement part of the first sensor 3 is displaced in the direction of the torque transmission axis 9 so as to be guided by the guide part 2a of the outer ring 2 so as to follow this. At the same time, when the outer ring inner surface load acts on the inner spherical surface of the outer ring 2 from the cage 7 and the outer spherical surface 7a of the cage 7 is displaced to the outer diameter side, the measuring part of the second sensor 4 is displaced to the outer diameter side. . Then, the track load and the outer ring inner spherical load derived by detecting the displacement amount of the measuring part of each sensor 3 and 4 are recorded by the data processing system.

  In the present invention, among the side wall surfaces of the measurement unit 3 a provided in the first sensor 3, the side wall surface 3 a 1 on the side close to the outer spherical surface 7 a of the cage 7 is respectively connected to the axis 9 extending in the torque transmission direction of the ball 6. Since they are formed in parallel, the angle β between the measurement unit side wall surface 3a1 of the first sensor 3 and the outer spherical surface 7a of the cage 7 adjacent to the first sensor 3 is larger than that in the conventional configuration. . Therefore, the stress from the adjacent cage 7 is less likely to act on the measurement unit 3a of the first sensor 3, and only the track load to be measured acts on the measurement unit 3a of the first sensor 3. As a result, since the measuring unit 3a of the first sensor 3 is displaced in response to only the track load, the track load can be accurately measured. Further, in the conventional configuration, a new stress concentration portion is generated as much as the stress from the cage 7 acts on the measurement portion 3a, and there is a possibility that the durability of the sensor 3 (measurement portion 3a) is reduced. On the other hand, if it is the structure of the said invention, generation | occurrence | production of this new stress concentration part can be prevented, and the durable fall etc. of a durable life can be avoided.

  In the illustrated example, among the side wall surfaces of the measurement unit 3 a provided in the first sensor 3, the side wall surface 3 a 1 on the side close to the outer spherical surface 7 a of the cage 7 is an axis 9 extending in the torque transmission direction of the ball 6. However, if the track load can be measured accurately, it does not need to be completely parallel, and the side wall surface 3a1 on the side close to the outer spherical surface 7a of the cage 7 has an axis 9 It may be slightly inclined with respect to.

  In the above, the internal force measuring device 1 used for measuring the internal force of a so-called Zepper type constant velocity universal joint in which the inner diameter surface of the outer ring 2 and the outer diameter surface of the inner ring 5 are spherical surfaces has been described. In the internal force measuring apparatus 1 according to the present invention, the track groove of the outer ring 2 has a straight line portion parallel to the axis toward the opening side, and the track groove of the inner ring 5 faces toward the opposite opening side of the outer ring 2. It can also be suitably used for measuring the internal force of a so-called undercut-free type constant velocity universal joint having a linear portion parallel to the axis.

  In the above description, the internal force measuring device used for measuring the internal force of the constant velocity universal joint in which the balls 6 are equally distributed at six locations in the circumferential direction has been described, but the internal force measuring device 1 according to the present invention is described. Can be suitably used for measuring the internal force of a constant velocity universal joint in which balls 6 are equally distributed at eight locations in the circumferential direction.

  Although the present invention has been described above, the present invention is not limited to the above-described embodiments, and can of course be implemented in various forms without departing from the gist of the present invention. It is. The scope of the present invention is defined by the terms of the claims, and includes the equivalent meanings recited in the claims and all modifications within the scope.

It is sectional drawing which shows the internal force measuring apparatus for constant velocity universal joints which concerns on this invention. It is a perspective view of the 1st sensor shown in FIG. It is sectional drawing which shows the internal force measuring apparatus used for the internal force measurement of a double offset type constant velocity universal joint. It is sectional drawing which used the structure of the internal force measuring apparatus shown in FIG. 3 as an internal force measuring apparatus of a fixed type constant velocity universal joint.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Constant velocity universal joint 2 Outer ring 3 1st sensor 3a Measurement part 3a1 Side wall surface 4 2nd sensor 5 Inner ring 6 Ball 7 Cage 9 Axis line extended in the torque transmission direction of a ball

Claims (5)

An outer joint member having one end opened and having a track groove on the inner diameter surface, an inner joint member having a track groove paired with the track groove of the outer joint member on the outer diameter surface, the outer joint member, and the inner joint member And a plurality of balls disposed on a track formed by cooperation of the two track grooves, and a cage disposed between the outer joint member and the inner joint member and holding the ball. Of the internal forces acting inside the constant velocity universal joint when the joint is in operation, the measurement of the track load acting on the track groove of the outer joint member from the ball can be displaced in the torque transmission direction of the ball. In the internal force measuring device for a constant velocity universal joint provided with a sensor for detecting the amount of displacement of the provided measuring unit,
The measurement part has two opposing side wall surfaces guided along a guide part provided inside the outer joint member, and approaches the outer diameter surface of the cage of the two side wall surfaces. An internal force measuring device for a constant velocity universal joint, wherein the side wall surface on the side is formed in parallel with an axis extending in the torque transmission direction of the ball.   A sensor for measuring an inner joint surface load acting on the outer joint member from the cage among internal forces acting on the inside of the constant velocity universal joint in an operating state of the constant velocity universal joint is provided. The internal force measuring device for a constant velocity universal joint according to claim 1.   3. The constant velocity universal joint according to claim 1, wherein an inner diameter surface of an outer joint member and an outer diameter surface of the inner joint member are constituted by spherical surfaces. Internal force measuring device for constant velocity universal joints.   In the constant velocity universal joint, the track groove of the outer joint member has a straight portion parallel to the axis toward the opening side of the outer joint member, and the track groove of the inner joint member is opposite to the outer joint member. The internal force measuring device for a constant velocity universal joint according to claim 1, wherein the device has a linear portion parallel to the axis toward the opening side.   5. The internal force measurement for a constant velocity universal joint according to claim 1, wherein the constant velocity universal joint is configured such that the balls are equally distributed at eight locations in a circumferential direction. apparatus.

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