JP2003247915A - Rolling slide test method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method allowing evaluation of durability for rolling contact accompanied with slide of a ball and lubrication performance to be performed by a test piece concerning a mechanical part performing swing movement such as a uniform universal joint using a simple test facility. <P>SOLUTION: A first swing member 2 and a second swing member 3 capable of reciprocating and swinging around the same shaft axis O are prepared, and the test piece 15 and a plurality of balls 6 are overlapped and nipped between opposing faces. The plurality of balls 6 are put in each ball play fitting hole 8a provided in a holder 8 whose position is fixed and are arranged in the circumferential direction around the shaft axis O. The first and second swing members 2, 3 are reciprocated and swung in the reverse directions to each other in synchronization. Swing spans of both swing members 2, 3 are made different from each other. Consequently, rolling contact accompanied with slide is given to the test piece 15 by the ball 6. The first swing member 2 is on a drive side, and the rotation of the first swing member 2 is transmitted to the second swing member 3 through an inversion mechanism 4. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rolling slip test method for evaluating the durability and lubrication performance of a mechanical part that makes rolling contact with a rocking motion or a reciprocating motion while slipping, and in particular, it is a uniform speed control method. The present invention relates to a rolling slip test method for joints and the like.

[0002]

2. Description of the Related Art As shown in FIG. 2, a constant velocity universal joint used for the underbody of an automobile is composed of an inner ring 21, an outer ring 22, a ball 23, and a cage 24. In such a constant velocity universal joint, when the rotation of the shaft is transmitted at a differential angle, the ball 23 is inside the joint when the inner / outer ring 2
It makes a swinging motion while rolling on the orbital surfaces of 1 and 22. The raceway surface is the inner surface of the track grooves 26, 27. At this time, it is said that the ball 23 and the cage 24 interfere with each other at the end of the swing, so that some slippage occurs. As a result, under high load conditions, the outer ring 22 and the inner ring 2 are oscillated at the ends thereof.
1 is likely to cause peeling. Although FIG. 2 shows an example of a fixed type constant velocity universal joint, also in the slidable type constant velocity universal joint shown in FIG. Conventionally, the durability of such a constant velocity universal joint has been evaluated by a bench test using an actual constant velocity universal joint.

[0003]

However, because of the oscillating motion, even if damage occurs, it is difficult for it to appear as a phenomenon such as a change in vibration, and it is difficult to accurately grasp the life. Therefore, we considered using a test piece with a rolling tester accompanied by slippage. However, the conventional rolling-sliding tester is mostly rolling-sliding accompanied by unidirectional sliding, and unidirectional sliding is not suitable for tests such as constant velocity universal joints that perform reciprocating motion or oscillating motion. Rolling-sliding type testing machines for reciprocating and oscillating motions are also used in some parts, but they require large-scale equipment, and due to their large size, the reciprocating oscillating cycle is limited to around 10 Hertz, and constant speed. Insufficient for universal joint testing.

The object of the present invention is to make it possible to evaluate the durability and lubrication performance of rolling contact and sliding contact of a ball with a test piece for mechanical parts that perform oscillating motion and reciprocating motion, and the test equipment is simple. The object of the present invention is to provide a rolling-slip test method that requires only a small amount.

[0005]

The rolling and sliding test method of the present invention uses first and second swinging members which can swing back and forth around the same axis, and between the facing surfaces of both swinging members. , The test piece and a plurality of balls are overlapped and sandwiched. It is assumed that these balls are arranged in the ball loose fitting holes provided in the position-fixed cage and arranged in the circumferential direction around the axis. The first and second rocking members are repeatedly reciprocally rocked in opposite directions synchronously, and the rocking spans of both rocking members are made different from each other. As a result, rolling contact and sliding contact are given to the test piece by the ball. According to this method, the ball is swung while rolling on the test piece by repeatedly swinging the first and second swing members in opposite directions in synchronization with each other. At this time, the swing spans of the two swing members are different from each other, the position of the cage is fixed, and there is a slight gap between the ball and the inner surface of the ball loose fitting hole of the cage. Therefore,
When the ball oscillates on the test piece, pure rolling occurs near the center of the oscillating span, and sliding occurs at both ends due to interference between the ball and the cage. When the difference between the swing spans of the two swing members is changed, the slip ratio changes according to the difference. When the sign of the difference between the swing spans is reversed, the slip direction changes accordingly. In this way, rolling contact with the test piece accompanied by sliding in a swinging motion is obtained. Therefore, a test piece can be used to simulate the durability and lubrication performance of a mechanical component that swings and reciprocates with balls interposed. By changing the difference between the swing spans, the slip ratio can be changed quantitatively, and the slip direction can also be changed, so tests and evaluations that more accurately mimic the contact conditions according to the structure and usage conditions of machine parts. It can be performed. Also,
This test method is based on the
Since the second rocking member is used, simple test equipment is sufficient.

In the method of the present invention, one of the first and second rocking members is rockably driven,
The swinging motion of the swinging member on the driving side may be transmitted to the other swinging member via the reversing mechanism so that the swinging members may swing in opposite directions in synchronization with each other. The reversing mechanism is, for example, a rotary wheel that is rotatable around a rotation center orthogonal to the axis and a radial groove that is provided in each of the first and second rocking members and that extends in the radial direction of the rotary wheel. It has a first and a second engaging element that match each other, and the position of the rotation center can be changed in the axial direction. By changing the position of the center of rotation, the slip rate and the slip direction of the ball with respect to the test piece are set. By transmitting the swing by using the reversing mechanism in this way, the swinging motion of both swinging members in synchronization can be easily obtained by one driving source. By using, as the reversing mechanism, the rotating wheels that engage with the first and second swinging members as described above, the swing spans of the first and second swinging members can be changed by changing the position of the rotation center. Relationship changes. When the difference in swing span changes,
The slip ratio and slip direction of the ball with respect to the test piece change. Therefore, the slip ratio and the slip direction can be easily set quantitatively by changing the position of the center of rotation of the rotary wheel.

In the method of the present invention, the torque acting on the cage may be measured, and the frictional force of the rolling motion and the sliding motion acting on the test piece may be measured from the measured value.

This rolling-slip test method may be a test method using the above-mentioned test piece to evaluate the raceway surface on which the balls of the constant velocity universal joint roll. According to the method of the present invention, the contact state between the raceway surface of the constant velocity universal joint and the ball can be simulated on the test piece, and the test piece and the like can be tested and evaluated on the raceway surface of the constant velocity universal joint.

Further, in the present invention, the ball is used as a test piece, and the test piece and a plurality of balls are overlapped and sandwiched between the facing surfaces of the first and second swinging members, or the test piece. Alternatively, the ball may be sandwiched between the facing surfaces of the first and second rocking members. According to this method, the ball test in the mechanical component can be simulated.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described with reference to FIG. FIG. 1A is a broken side view showing a testing machine used in the rolling slip test method of this embodiment, and FIG. 1B is a front view of a reversing mechanism of the testing machine. The testing machine 1 is configured to perform a swinging motion of a first swinging member 2 and a first and a second swinging members 2 and 3 which are arranged to face each other about the same axis O so as to swing back and forth. And a reversing mechanism 4 that transmits the reversing direction to the second rocking member 3. The first swing member 2 is driven by a swing drive mechanism (not shown).
It is rockingly driven around the axis O. The swing drive mechanism converts the rotation of a continuously rotating motor into swing motion and transmits the swing motion. For example, the swing drive mechanism includes the motor and a crank mechanism that converts a rotation output of the motor into swing motion. . The swing span of the first swing member 2, that is, the reciprocating distance of the swing motion is set by the eccentric amount of the output shaft of the motor and the crank mechanism. The first and second rocking members 2 and 3 are, for example, arranged above and below each other. The positional relationship between the two rocking members 2 and 3 is not limited to the upper and lower sides, but in this specification, the first rocking member 2 side will be described as the upper side.

The second swinging member 3 is a lifting mechanism (not shown).
Can be moved up and down. On the upper end surface of the swinging member 3, there is provided a test piece installation base 5 for installing the ring-shaped test piece 15 concentrically with the axis O. The elevating mechanism of the second swinging member 3 serves as a load means for the thrust load. This elevating mechanism is composed of a feed screw mechanism and elastically applies a thrust load by interposing a spring member such as a coil spring. In addition, this elevating mechanism is capable of measuring the applied load through a load measuring means such as a load cell. Second
On the lower end surface of the first rocking member 2 facing the upper end surface of the rocking member 3, a plurality of (for example, 3
A ring-shaped thrust ring 7 sandwiching the individual ball 6 with the test piece 15 is provided concentrically with the axis O. A retainer 8 that holds the ball 6 is disposed between the test piece installation base portion 5 and the thrust wheel 7. By inserting the balls 6 into the plurality of ball loose fitting holes 8a provided in the cage 8, the balls 6 are arranged at equal intervals in the circumferential direction around the axis O. The retainer 8 has a lever 8b protruding outward.
And is fixed to the base 12 via the lever 8b. Load detecting means (not shown) such as a strain gauge is attached to the lever 8b as a means for detecting the torque acting on the cage 8.

The reversing mechanism 4 includes a first swing member 2 and a second swing member 2.
3, engaging members 9 and 10 projectingly provided on one side surface, and a rotary wheel 11 having grooves 11a and 11b slidably engaged with the engaging members 9 and 10, respectively. The rotating wheel 11 is a support body (not shown) installed on one side of the swinging members 2 and 3 so as to be rotatable about a rotation center O1 orthogonal to the axis O of the swinging members 2 and 3. ) Is supported by. This support is
The height of the rotation center O1 of the rotary wheel 11 can be adjusted by adjusting the position of the support body so that the position in the direction along the axis O, that is, the ascending / descending position can be adjusted. The pair of grooves 11a and 11b of the rotating wheel 11 are radial grooves that sandwich the rotation center O1. Rotating wheel 1
When the first swinging member 2 is driven to swing, the first swinging member 1 reciprocally swings around the rotation center O1 due to the engagement between the engaging element 9 and the groove 11a. The reciprocal swing of the rotary wheel 11 is transmitted to the second swing member 3 by the engagement of the groove 11b and the engagement element 10,
The second swinging member 3 swings around the axis O in the direction opposite to that of the first swinging member 2.

Next, a test method using the tester 1 having the above-mentioned structure will be described. A ring-shaped test piece 15 is installed on the second rocking member 3, and the ball 6 and the test piece 15 held by the cage 8 are moved by raising the second rocking member 3 to both rocking members 2. , 3, sandwiched under load. The test piece 15 has a material, a surface property, a lubrication condition, etc. set corresponding to a mechanical part such as a constant velocity universal joint to be evaluated by a test. The reversing mechanism 4 adjusts the height of the rotation center O1 of the rotating wheel 11 so that the relationship between the distances a and b from the rotation center O1 of the rotating wheel 11 to the engaging elements 9 and 10 is, for example, a <b. To do.

In this state, when the first swinging member 2 is swingably driven by the crank mechanism of the swinging drive mechanism, the motion is transmitted to the second swinging member 3 via the reversing wheel 11,
The phase of the second swing member 3 is 180 ° with the first swing member 2.
Performs a reciprocating reciprocating rocking motion. In this swinging motion,
Since the positional relationship of the upper and lower engaging elements 9 and 10 with respect to the reversing wheel 11 is a <b, as shown by the lengths of arrows A and B in FIG. The swing span of the swing member 3 of 2 becomes larger. At this time, the cage 8
Is fixed in position, and the ball loose fitting hole 8 of the retainer 8 is fixed.
Since there is a slight gap between a and the ball 6, the ball 6 is a pure rolling that does not slip near the center of the swing, and at both ends of the swing there is slip due to the interference between the ball 6 and the cage 8. It will be.

When the position of the rotation center O1 of the reversing mechanism 4 is changed, the slip ratio of the ball 6 with respect to the test piece 15 is changed. When the rotation center O1 is at the same height position as the center of the ball 6 (this is referred to as the neutral position), the slip ratio is zero and the rolling is pure. When the rotation center O1 is moved to the first swinging member 2 side from the neutral position, the relationship of a <b is established, and the second swinging member 3 is larger than the first swinging member 2. Amplitude, and the swing span, which is the round trip distance, becomes longer. In this case, the sliding direction is on the acceleration side with respect to the rolling direction. When the rotation center O1 is moved to the second swinging member 3 side from the neutral position, the second swinging member 3 has a smaller amplitude than the first swinging member 2, and the swing span which is the reciprocating distance. Becomes shorter. In this case, the sliding direction is on the deceleration side with respect to the rolling direction. The swing span of the first swing member 2 on the drive side is
It is set by the amount of eccentricity between the motor and the crankshaft in the swing drive mechanism (not shown).

The position of the center of rotation O1 is changed by adjusting the position of the support (not shown) that supports the rotating wheel 11 as described above, but a jig for the slip ratio (not shown) to be tested in advance is used. If (1) is prepared and set, the same slip ratio can be maintained even if the swing span changes. The retainer 8 is fixedly installed and holds the position of the ball 6 to cause slippage due to the difference in swing span between the swing members 2 and 3.
The ball 6 receives a rotational force about the axis O. Since this rotational force causes strain in the lever portion 8b, it can be measured by a load measuring means such as a strain gauge provided in the lever portion 8b. From this rotational force, the frictional force and the friction coefficient between the test piece 15 and the ball 6 can be obtained. The thrust load is measured by a load load detecting means such as the load cell provided in an elevating mechanism (not shown) of the second swinging member 3. When three balls 6 are interposed, the same test piece 15 can be tested at least three times.

According to the test method and the tester 1 of this embodiment, a plunging type constant velocity universal joint is represented.
It is possible to perform a test that reproduces the use condition in which a large sliding motion is added by plunging during rolling motion under the load of high surface pressure, and the test of the test piece 15 shows the same damage mode as the constant velocity universal joint of the actual machine. The damage form can be reproduced. This damage mode is, for example, the separation of the raceway surface. According to the experiment,
The tester 1 was able to reproduce peeling in a form similar to the peeling that occurs in an actual constant velocity universal joint. The form of peeling is
The starting point was the surface of the rocking end. It was also proved that the slip ratio of the rolling sliding motion can be added quantitatively and reliably, and the durability evaluation of the raceway surface and the balls 6 and the evaluation of the lubricant can be efficiently performed. The disc-shaped test piece 15 of the evaluation test material is easy to manufacture, and the same test piece can be tested a plurality of times. By measuring the rotational force acting on the cage 8 as described above, it is possible to measure the frictional force during the rolling sliding motion, which is effective for evaluating the lubricant and the finished surface property. In the confirmation of the presence or absence of peeling, if the retainer 8 or the test piece 15 is removed from the testing machine 1, it will be displaced from the initial set position. Therefore, with the retainer 8 or the test piece 15 still set,
It is preferable to confirm peeling using a fiberscope.

By rearranging the test method of this embodiment and the operation and effect of the tester 1, it is possible to carry out a test satisfying the following respective conditions. ． It is possible to handle from pure rolling contact to rolling-sliding contact with sliding. ． The slip direction can be set to the acceleration side or the deceleration side with respect to the rolling direction. ． Sliding rate is from zero (pure rolling) to several tens (eg 50)%
The above is possible. ． The set slip ratio is given to the entire region during the swing motion. ． The tester 1 can be made compact, has good operability, is easy to handle, and can perform a high-speed reciprocating motion cycle (tens of hertz). In particular, the tester 1 is compact and can handle high surface pressure, and the cycle of reciprocating rocking motion can be a high cycle (max 1500 cpm), which is unprecedented in the conventional example. Can be a testing machine.

In the above embodiment, the case where the test is performed on the test piece 15 has been described.
It is also possible to carry out the test by using In that case, the test piece 15 may be used, or a thrust wheel (not shown) may be used instead of the test piece 15.

[0020]

According to the rolling slip test method of the present invention, the first and second swinging members which can swing back and forth around the same axis are used, and the test piece is provided between the facing surfaces of both swinging members. The plurality of balls are overlapped and sandwiched, and the plurality of balls are arranged in the ball loose fitting holes provided in the position-fixed retainer and arranged in the circumferential direction around the axis, and the first ball And the second rocking member is repeatedly reciprocally rocked in opposite directions in synchronization with each other, and the rocking spans of both rocking members are made different from each other, so that the ball makes rolling contact and sliding on the test piece. Because it is a method of giving contact,
With respect to mechanical parts that perform oscillating motion and reciprocating motion, the durability against rolling contact accompanied by sliding of balls and the lubrication performance can be evaluated by test pieces, and the test equipment is simple.

[Brief description of drawings]

FIG. 1A is a partially omitted cutaway front view of a testing machine used in a rolling slip test method according to an embodiment of the present invention, and FIG. 1B is a front view of a reversing mechanism thereof.

FIG. 2 is a cross-sectional view showing an example of a constant velocity universal joint which is a test target of the rolling slip test method.

FIG. 3 is a cross-sectional view showing another example of a constant velocity universal joint which is a test target of the rolling slip test method.

[Explanation of symbols]

1 ... Testing machine 2 ... First swing member 3 ... The second swing member 4 ... Inversion mechanism 6 ... ball 7 ... Thrust wheel 8 ... Cage 8a ... Ball loose fitting hole 8b ... lever 9, 10 ... Engagement element 11 ... Rotating wheel 11a, 11b ... Groove 15 ... Test piece O ... Shaft member axis O1 ... Center of rotation of the rotating wheel

Continued front page    F term (reference) 2G024 AB12 BA12 BA19 CA11 CA12                       DA08 DA09 DA11 DA12 EA08                       EA13

Claims (5)

[Claims] 1. A first and a second swinging member which can swing back and forth around the same axis are used, and between the facing surfaces of both swinging members,
The test piece and a plurality of balls are overlapped and sandwiched, and the plurality of balls are arranged in the ball loose fitting hole provided in the position-fixed retainer and arranged in the circumferential direction around the axis, The first and second oscillating members are repeatedly reciprocally oscillated in opposite directions in synchronism with each other, and the oscillating spans of the oscillating members are made different from each other, so that the ball is rolled on the test piece. Rolling-slip test method that gives contact and sliding contact. 2. One of the first and second oscillating members is oscillated and oscillated, and the oscillating motion of the oscillating member on the drive side is oscillated by the other oscillating member through the reversing mechanism. By transmitting it to the moving member, both swinging members are made to swing in opposite directions in synchronization with each other, and the reversing mechanism includes a rotating wheel rotatable about a rotation center orthogonal to the axis and the first rotating member. And a first and a second engaging element which are respectively provided on the second rocking member and which engage with a radial groove of the rotating wheel, and the position of the rotation center can be changed in the axial direction. The rolling slip test method according to claim 1, wherein the slip ratio and the slip direction of the ball with respect to the test piece are set by changing the position of the rotation center. 3. The torque acting on the cage is measured,
The rolling-slip test method according to claim 1 or 2, wherein the frictional force of rolling motion and sliding motion acting on the test piece is measured from the measured value. 4. The rolling slip test method according to claim 1, which is a test performed using the test piece to evaluate a raceway surface on which a ball of a constant velocity universal joint rolls. 5. The rolling slip test method according to claim 1, wherein the ball is used as a test sample, and the test piece is provided between the facing surfaces of the first and second rocking members. A rolling slip test method in which a plurality of balls are stacked and sandwiched, or the test piece is omitted and the balls are sandwiched between the facing surfaces of the first and second rocking members.