JP2020085539A - Joint inspection method - Google Patents

Abstract

To provide a joint inspection method with which it is possible to shorten the time needed for inspection.SOLUTION: An inspection program of the present invention includes: steps S11, S12, S13 and S14 for measuring a total rotation amount C when, while one end of a revolving shaft member is unrotatably fixed together with a joint, the other end of the revolving shaft member is rotated together with the joint by forward and reverse rotations until a prescribed rated torque T and a negative torque T are reached; a step S15 for acquiring a torsion rotation amount A and a swing rotation amount B due to the torsion of the revolving shaft member in forward and reverse rotations; a step S16 for subtracting the rotation amounts A, B from the total rotation amount C and calculating a clearance D of the joint; and steps S17, S18 and S19 for comparing the clearance D with a preset reference clearance D1 and determining whether or not the clearance D is good.SELECTED DRAWING: Figure 3

Description

The present invention relates to an inspection method for a joint connected to a rotary shaft member.

Conventionally, for example, a joint inspection method disclosed in Patent Document 1 below is known. In this conventional inspection method, a normally assembled constant velocity joint is applied to a drive shaft constituted by connecting both ends of a rotary shaft member to a rotary drive force, and after a predetermined time has elapsed, the rotary shaft is rotated. To stop. In the conventional inspection method, the reduction amount of the rotational torque value of the rotary shaft member immediately after the rotation is stopped is measured. Similarly, in the conventional inspection method, the decrease amount of the rotational torque value in the drive shaft configured by connecting the constant velocity joint, one or both of which is erroneously assembled to the rotating shaft member, is also measured.

Then, in the conventional inspection method, a rotational driving force is applied to the drive shaft assembled as a product, the rotation is stopped after a predetermined time has elapsed, and the reduction amount of the rotational torque value is measured. Thus, in the conventional measuring method, the measured reduction amount is compared with the reduction amount measured in advance as described above, so that the quality of the assembled state of the drive shaft assembled as a product can be determined. ing.

JP, 2010-203950, A

By the way, in the product in which the joint is connected to the rotary shaft member, the clearance set in the joint is properly secured, and it is necessary to inspect whether or not the rotation can be transmitted efficiently, with respect to all the produced products. Is desirable. In this case, in order to improve productivity, it is extremely effective to shorten the time required for the inspection (so-called cycle time).

In this regard, in the above-described conventional inspection method, it is necessary to apply a rotational driving force to the product, rotate the product until a predetermined time has elapsed, and then stop the rotation, and then measure the amount of decrease in the rotational torque value. .. As a result, the time required for the inspection may increase. Therefore, an inspection method capable of inspecting the quality of the joint clearance by shortening the time required for the inspection is desired.

The present invention has been made to solve the above problems, and an object thereof is to provide a joint inspection method capable of reducing the time required for the inspection.

The joint inspection method according to the present invention is a joint inspection method which is provided at an end portion of a rotary shaft member, holds the rotary shaft member, and inspects whether or not a clearance in a rotational direction is good in a joint that transmits rotation to the rotary shaft member. When the joint is rotated together with the other end of the rotary shaft unit by the normal rotation and the reverse rotation until a predetermined specified torque is achieved, with one end of the rotary shaft unit including the rotary shaft member and the joint fixed in a non-rotatable state. Measured in the total rotation amount measurement process of measuring the total rotation amount, the twist rotation amount acquisition process of acquiring the twist rotation amount due to the twist of the rotation shaft member in the forward rotation and the rotation shaft member in the reverse rotation, and the total rotation amount measurement process. By subtracting the twist rotation amount acquired in the twist rotation amount acquisition step from the total rotation amount, a clearance calculation step of calculating the clearance of the joint, and comparing the clearance calculated in the clearance calculation step with a preset reference clearance, A pass/fail determination step of determining whether the clearance is good or bad.

According to this, in the joint inspection method of the present invention, in the total rotation amount measuring step, the other end of the rotary shaft unit is normally rotated until a predetermined specified torque is obtained with one end of the rotary shaft unit fixed in a non-rotatable state. And reversely rotating, in other words, the rotating shaft member that constitutes the rotating shaft unit is only twisted by the specified torque. Therefore, the joint inspection method of the present invention can shorten the time compared to the case where the rotary shaft member and the joint (rotary shaft unit) are continuously rotated integrally as in the conventional inspection method. it can.

Further, in the joint inspection method of the present invention, the torsional rotation amount of the rotary shaft member can be acquired in the torsional rotation amount acquisition step. Further, in the joint inspection method of the present invention, in the clearance calculation step, the clearance is calculated by subtracting the twist rotation amount when the normal rotation and the reverse rotation are performed from the total rotation amount measured in the total rotation amount measurement step. be able to.

Thus, the joint inspection method of the present invention can calculate the clearance of the joint only by measuring the total rotation amount of the rotary shaft unit in the total rotation amount measurement step, and determines the quality of the clearance in the quality determination step. can do. Therefore, the joint inspection method of the present invention, like the conventional inspection method described above, rotationally drives the rotary shaft member and the joint (rotary shaft unit) over time, and then decreases the rotational torque value with the passage of time. It is possible to significantly reduce the time required for measurement as compared with the case of measuring the amount of decrease.

It is a schematic diagram showing composition of an inspection device used for a joint inspection method by the present invention. It is a partial cross section figure which shows the structure of the rotating shaft unit which has a joint inspected by the inspection apparatus of FIG. 6 is a flowchart of an inspection program corresponding to a joint inspection method. It is a graph which shows the relationship between an electric current and torque. It is a graph which shows the relationship between rotation amount and torque.

(1. Overview of inspection device 10)
An embodiment of the joint inspection method of the present invention will be described with reference to the drawings. As shown in FIG. 1, the inspection device 10 for performing the joint inspection method according to the present embodiment includes a holding unit 11, a motor 12, a displacement sensor 13, and a control unit 14.

The holding portion 11 is non-rotatably fixed, and holds one end of a drive shaft 100, which is an inspection target in the present embodiment and serves as a rotary shaft unit described later, in a non-rotatable manner. The motor 12 generates torque according to the current supplied by the control of the control unit 14 as described later, and rotates the other end of the drive shaft 100 (more specifically, twists as described later). The displacement amount sensor 13 detects and outputs the displacement amount along the rotation direction of the drive shaft 100, that is, the rotation amount generated by the torque input from the motor 12 to the other end of the drive shaft 100. Here, the rotation amount output by the displacement amount sensor 13 corresponds to the rotation angle of the drive shaft 100.

The control unit 14 is a microcomputer having a CPU, a ROM, a RAM, an interface, etc. (not shown), and controls the operation of the inspection device 10 as a whole. The control unit 14 is electrically connected to the motor 12 and the displacement amount sensor 13. As a result, the control unit 14 controls the operation of a drive circuit (not shown) to supply a current to the motor 12 to drive it to rotate. Further, the control unit 14 inputs a signal representing the rotation amount (angle) detected by the displacement amount sensor 13 and executes the inspection program described later.

(2. Outline of joint)
The drive shaft 100 as a rotary shaft unit is mounted on a vehicle. For example, one side is connected to wheels to transmit the input driving force of the engine to the wheels, and the other end is via a vehicle differential. Is connected to the engine and inputs the driving force of the engine. As shown in detail in FIG. 2, the drive shaft 100 includes a shaft member 110 as a rotating shaft member, a constant velocity joint 120 and a constant velocity joint 130 as joints connected to both ends of the shaft member 110. I have it.

The shaft member 110 is, for example, a solid round bar shape, and the length and diameter are set according to the specifications and mounting requirements for the vehicle. The constant velocity joint 120 is a joint type fixed ball type constant velocity joint (Rzeppa type constant velocity joint), and is an outboard joint of the drive shaft 100. The constant velocity joint 120, as shown in FIG. 2, has an outer ring 122 having a plurality of outer ring ball grooves 121, an inner ring 124 having a plurality of inner ring ball grooves 123, a plurality of balls 125, a retainer 126, and a shaft portion. 127. Since the structure of the Rzeppa type constant velocity joint is well known and is not directly related to the present invention, it will be briefly described below.

The outer ring ball groove 121 is formed on the inner peripheral surface of the outer ring 122 so as to extend in the axial direction of the outer ring 122. The outer ring ball groove 121 is formed in a substantially arcuate concave shape. The inner ring ball groove 123 is formed on the outer peripheral surface of the inner ring 124 so as to extend in the axial direction of the inner ring 124. The inner ring ball groove 123 is formed in a substantially arcuate concave shape.

The ball 125 is arranged so as to be sandwiched by the outer ring ball groove 121 of the outer ring 122 and the inner ring ball groove 123 of the inner ring 124 facing the outer ring ball groove 121. The ball 125 is rollably engaged with the outer race ball groove 121 and the inner race ball groove 123 in the circumferential direction. Therefore, the ball 125 transmits torque between the outer ring 122 and the inner ring 124. Here, a clearance is provided between the ball 125 and the outer ring ball groove 121 and the inner ring ball groove 123. The retainer 126 is formed in an annular shape. The shaft 127 is connected to the wheels.

The constant velocity joint 130 is, for example, a tripod type constant velocity joint, and is an inboard joint of the drive shaft 100. The constant velocity joint 130 is briefly described below because the structure itself of the tripod type constant velocity joint is well known and is not directly related to the present invention.

The constant velocity joint 130, as shown in FIG. 2, includes an outer member 131 and an inner member 132 connected to the shaft member 110. The outer member 131 has a cup-shaped portion 133 having a bottomed cylindrical shape, and a shaft portion 134 formed to project from one end of the cup-shaped portion 133. Here, the shaft portion 134 is connected to the differential of the vehicle.

A track groove (not shown) is formed on the inner wall of the cup-shaped portion 133, and the trunnion 135 forming the inner member 132 is inserted and assembled in the track groove. As a result, the trunnion 135 becomes relatively movable along the track groove together with the connected shaft member 110, and transmits the rotation of the shaft portion 134 to the shaft member 110 via the track groove, that is, the outer member 131. Here, a rolling member (roller or the like) is provided and a clearance is provided between the trunnion 135 and the track groove.

(3. Inspection method)
The control unit 14 (more specifically, the CPU) starts execution of the inspection program whose flowchart is shown in FIG. 3 in step S10. In the subsequent step S11, the control unit 14 drives the motor 12 so that the torque input to the drive shaft 100 via the constant velocity joint 130 becomes the specified torque T, and the drive shaft 100, which is a rotary shaft unit, is driven. Rotate forward.

In this case, the control unit 14 supplies a current I corresponding to the specified torque T to the motor 12 based on a current-torque map that represents a preset relationship between current and torque, as shown in FIG. As a result, the motor 12 rotates the drive shaft 100 in the forward direction until the specified torque T is reached without torque control by the control unit 14. Then, the control unit 14 inputs a signal indicating the displacement amount detected by the displacement amount sensor 13, and the rotation amount of the drive shaft 100 when the drive shaft 100 is normally rotated until the specified torque T represented by the signal ( Angle) is temporarily stored in RAM. When the control unit 14 rotates the drive shaft 100 forward until the specified torque T is reached, the control unit 14 proceeds to step S12.

In step S12, the control unit 14 sets the rotation amount (angle) input from the displacement amount sensor 13 as the reference rotation amount. That is, as shown in FIG. 5, the control unit 14 sets a reference rotation amount (for example, “0”) of the rotation amount (angle) in the present inspection at the point P1 in which the drive shaft 100 is normally rotated until the specified torque T is reached. ). In this way, when the rotation amount (angle) when the specified torque T is obtained by the normal rotation is set as the reference rotation amount, the control unit 14 proceeds to step S13.

In step S13, the control unit 14 controls the motor 12 so that the torque input to the drive shaft 100 becomes the negative specified torque T whose absolute value is the same as that of the specified torque T input in step S11 and whose sign is inverted. To drive the drive shaft 100 to rotate in the reverse direction. In this case as well, similar to step S11, the control unit 14 determines, based on the current-torque map, the current I having the same absolute value as the current I in the positive rotation corresponding to the negative specified torque T and the sign inverted. I is supplied to the motor 12.

As a result, the motor 12 reversely rotates the drive shaft 100 until the negative specified torque T is reached. Then, the control unit 14 inputs a signal indicating the displacement amount detected by the displacement amount sensor 13, and rotates the drive shaft 100 when it is reversely rotated until the negative specified torque T represented by the signal is obtained. The amount (angle) is temporarily stored in RAM. When the control unit 14 reversely rotates the drive shaft 100 until the negative specified torque T is reached, the process proceeds to step S14.

In step S14, the control unit 14 changes the total torque when the torque input to the drive shaft 100 is changed from the specified torque T to the negative specified torque T based on the reference rotation amount set in step S12. (Amount of change in angle) C is measured (calculated). Specifically, as shown in FIG. 5, the control unit 14 sets the reference rotation amount (angle) at the point P1 corresponding to the specified torque T and the rotation amount (angle) at the point P2 corresponding to the negative specified torque T. The difference is measured (calculated) as the total rotation amount (angle change amount) C. When the total rotation amount (angle change amount) C is measured (calculated) in this way, the control unit 14 proceeds to step S15.

In step S15, the control unit 14, as shown in FIG. 5, the twist rotation amount (twist) generated in the shaft member 110 when the drive shaft 100 is positively rotated to the specified torque T in step S11. Angle) A is calculated and acquired. Further, the control unit 14 calculates and obtains the torsional rotation amount (twisting angle) B generated in the shaft member 110 when the drive shaft 100 is reversely rotated so as to have the negative specified torque T in step S13. To do.

When the specified torque T or the negative specified torque T is input, the shaft member 110 forming the drive shaft 100 is twisted and deformed. The magnitude of the twist deformation, that is, the twist angle (rotation amount) is proportional to the torque input to the shaft member 110. The proportional coefficient in this proportional relationship can be set in advance by using the torsional rigidity as a characteristic of the shaft member 110 and the length of the shaft member 110.

The torsional rigidity can be obtained by multiplying the torsional constant (torsion moment of area) and the shear elastic modulus (lateral elastic modulus). The twist constant can be obtained by using the diameter of the shaft member 110, and the shear elastic modulus is determined by the material forming the shaft member 110. Therefore, the torsional rigidity can be a specification of the shaft member 110 forming the drive shaft 100, in other words, a unique value for each product. Further, the length of the shaft member 110 can also be a unique value for each product. Accordingly, the proportional relationship between the twist angle (rotation angle) and the torque input to the shaft member 110 can be expressed by using the inclination K (proportional coefficient) in the twist region that can be preset as an eigenvalue for each product.

Based on this, the control unit 14 calculates the twist rotation amount (twist angle) A of the shaft member 110 when the specified torque T is input, using the above-described inclination K (proportional coefficient). Specifically, as shown in FIG. 5, the control unit 14 uses the straight line that passes through the point P1 using the slope K (proportionality coefficient), and the input torque is unloaded in the state of "0". The point Pa is obtained, and the difference between the rotation amount (angle) at the point P1 and the calculated rotation amount (angle) at the point Pa is calculated and acquired as the twist rotation amount (twist angle) A.

Similarly, the control unit 14 calculates the twist rotation amount (twist angle) B of the shaft member 110 when the negative specified torque T is input, using the above-described inclination K (proportional coefficient). Specifically, as shown in FIG. 5, the control unit 14 uses the straight line that passes through the point P2 with the slope K (proportional coefficient) to determine the point Pb when the input torque is “0”. The difference between the rotation amount (angle) at the point P2 and the calculated point Pa is calculated and acquired as the twist rotation amount (twist angle) B. Then, when the control unit 14 calculates and acquires the twist rotation amounts (twist angles) A and B, the process proceeds to step S16.

In step S16, the control unit 14 calculates the total rotation amount (angle change amount) C measured (calculated) in step S14, and the twist rotation amounts (twist angle) A and B acquired in step S15. Is used to calculate the total clearance D of the constant velocity joints 120 and 130. That is, the control unit 14 calculates the clearance D (=C−A−B) by subtracting the twist rotation amounts (twist angles) A and B from the total rotation amount (angle change amount) C. Then, after calculating the clearance D, the control unit 14 proceeds to step S17.

In step S17, the control unit 14 compares the clearance D calculated in step S16 with a reference clearance D1 preset for determining whether the drive shaft 100 as a product is a good product or a defective product. That is, if the clearance D is less than or equal to the reference clearance D1, the control unit 14 determines “Yes” and proceeds to step S18. On the other hand, if the clearance D is larger than the reference clearance D1, the control unit 14 determines “No” and proceeds to step S19.

In step S18, the control unit 14 determines that the drive shaft 100 is a good product based on the determination process in step S17. In this case, the control unit 14 displays on a display device (not shown) (display display, lamp, etc.) that the inspected drive shaft 100 is non-defective. The drive shaft 100 thus determined to be non-defective is sent to a subsequent process (for example, a vehicle assembly process). When the control unit 14 determines that the product is non-defective, the control unit 14 proceeds to step S20 and ends the execution of the inspection program.

In step S19, the control unit 14 determines that the drive shaft 100 is defective based on the determination process in step S17. In this case, the control unit 14 displays on the display device that the inspected drive shaft 100 is defective. The drive shaft 100 thus determined to be defective is not sent to a subsequent process (for example, a vehicle assembly process), and is isolated from the drive shaft 100 manufacturing line. When the control unit 14 determines a defective product, the control unit 14 proceeds to step S20 and accommodates the execution of the inspection program.

As can be understood from the above description, in the joint inspection method according to the above-described embodiment, the joint is provided at the end of the shaft member 110, which is a rotary shaft member, to hold the shaft member 110 and transmit rotation to the shaft member 110. A joint inspection method for inspecting quality of a clearance D in a rotation direction of constant velocity joints 120, 130 as joints, which is one end of a drive shaft 100 as a rotary shaft unit including a shaft member 110 and constant velocity joints 120, 130. Total rotation amount measurement for measuring the total rotation amount C when the other end of the drive shaft 100 is rotated by the forward rotation and the reverse rotation until the predetermined specified torque T and the negative specified torque T are obtained in a state in which is fixed non-rotatably. The process (step S11, step S12, step S13 and step S14 in the inspection program), and the twist rotation amount A and the twist rotation amount B due to the twist of the shaft member 110 in the forward rotation and the shaft member 110 in the reverse rotation are calculated as follows. The torsional rotation amount acquisition step (step S15 in the inspection program) calculated based on the torsional characteristics, and the torsional rotation amount acquisition step (from the total rotation amount C measured in the total rotation amount measurement step (steps S11, S12, S13, S14)). In the clearance calculation step (step S16 in the inspection program) for calculating the clearance D of the constant velocity joints 120, 130 by subtracting the torsional rotation amounts A, B acquired in step S15) and the clearance calculation step (step S16). The pass/fail determination step (step S17, step S18, and step S19 in the inspection program) of comparing the clearance D with a preset reference clearance D1 to determine the quality of the clearance D is included.

According to this, in the joint inspection method of the present embodiment, in the total rotation amount measuring step (steps S11, S12, S13, S14), the predetermined prescribed torque T is fixed while one end of the drive shaft 100 is non-rotatably fixed. Until the other end, the other end of the drive shaft 100 is rotated in the forward and reverse directions, in other words, the shaft member 110 is only twisted by the specified torque T and the specified negative torque T. Therefore, the joint inspection method of the present embodiment can shorten the time as compared with the case where the drive shaft 100 is continuously rotated as in the conventional inspection method described above.

Further, the joint inspection method of the present embodiment is such that, in the torsional rotation amount acquisition step (step S15), the torsion when the specified torque T and the negative specified torque T are input based on the torsional characteristics peculiar to the shaft member 110. The rotation amounts A and B can be calculated and acquired. Further, in the joint inspection method of the present embodiment, in the clearance calculation step (step S16), normal rotation and reverse rotation are performed based on the total rotation amount C measured in the total rotation amount measurement step (steps S11, S12, S13, S14). The clearance D (=C−A−B) can be calculated by subtracting the torsional rotation amounts A and B when rotating.

As a result, the joint inspection method of the present embodiment only measures the total rotation amount C of the drive shaft 100 in the total rotation amount measurement step (steps S11, S12, S13, S14), and the constant velocity joints 120, 130. The clearance D can be calculated, and the quality of the clearance D can be determined in the quality determination step (steps S17, S18, S19). Therefore, in the joint inspection method of the present embodiment, like the conventional inspection method described above, the drive shaft 100 is rotationally driven over time, and thereafter, the decrease amount of the rotational torque value that decreases with the passage of time is measured. Compared with the case, the time required for measurement, that is, the cycle time can be shortened significantly.

In this case, the twist rotation amount acquisition step (step S15) represents the relationship between the rotation amount of the shaft member 110 and the torque input to the shaft member 110, and the inclination K in the twist region of the shaft member 110 is made constant as a twist characteristic. Then, using the inclination K, the torsional rotation amounts A and B of the shaft member 110 when the prescribed torque T and the negative prescribed torque T are unloaded from the state where the prescribed torque T and the negative prescribed torque T are input are calculated. .. In this case, the inclination K is determined based on the diameter of the shaft member 110 and the length of the shaft member 110.

According to this, the inclination K in the twist region, which is the twist characteristic, is made constant as an eigenvalue in accordance with the diameter and length of the shaft member 110, that is, the specifications determined for each drive shaft 100 as a product. Therefore, the control unit 14 can be used to calculate the twist rotation amounts A and B. As a result, the control unit 14 can calculate the twist rotation amounts A and B only by setting the inclination K that is made constant according to the drive shaft 100 that is a product. The amount of calculation for calculation can be reduced, and as a result, the time required for inspection can be shortened.

Further, in these cases, in the total rotation amount measuring step (step S12), the state in which the drive shaft 100 is rotated until the specified torque T is reached at the forward rotation, which is one of the forward rotation and the reverse rotation, is set as the reference rotation amount. The reverse rotation, which is the other of the forward rotation and the reverse rotation, rotates the drive shaft 100 until the negative specified torque T is reached, and the total rotation amount C is measured. According to this, the control unit 14 can set the rotation amount (angle) obtained by rotating the drive shaft 100 until the negative specified torque T is obtained in the reverse rotation as the total rotation amount C, and shorten the time required for measurement. As a result, the time required for the inspection can be shortened.

Further, in these cases, in the total rotation amount measuring step (steps S11 and S13), the motor 12 that is rotationally driven by being supplied with the current I corresponding to the specified torque T based on the preset relationship between the current and the torque. Causes the other end of the drive shaft 100 to rotate. According to this, the control unit 14 does not need to sequentially control the torque of the motor 12 to the specified torque T, and can rapidly drive the motor 12 to rotate, so that the time required for measurement can be shortened. You can

(4. First modification)
In the above embodiment, the control unit 14 supplies the electric currents corresponding to the specified torque T and the specified negative torque T in the steps S11 and S13, so that the motor 12 causes the specified torque T and the specified negative torque T to be generated. As an input of T to the drive shaft 100, that is, the motor 12 is driven in feedforward control.

In this case, as shown by the one-dot chain line in FIG. 1, when the inspection device 10 includes the load cell 15 that detects the torque input to the drive shaft 100, the motor 12 is driven by the current corresponding to the specified torque T. It is also possible to monitor that the torque input to the drive shaft 100 after driving and applying the specified torque T (when the motor 12 is stopped) is the specified torque T. In this case, the monitoring result by the load cell 15 is not fed back to the control unit 14, but is fed back to various control devices provided in the motor 12, for example. As a result, the motor 12 can autonomously input the specified torque T to the drive shaft 100.

(5. Second modification)
In the above embodiment, the control unit 14 causes the drive shaft 100 to rotate forward until the specified torque T is reached in step S11 by executing the inspection program, and in step S12 the reference rotation amount (that is, point P1). Was set. Then, the control unit 14 reversely rotates the drive shaft 100 in step S13 until the negative specified torque T is reached, and measures the total rotation amount C based on the reference rotation amount in step S14.

However, the total rotation amount C is measured as one of forward rotation and reverse rotation when the drive shaft 100 is reversely rotated until the negative specified torque T is obtained in step S11 and is reversely rotated in step S12. Is set as the reference rotation amount, and the drive shaft 100 is normally rotated until the specified torque T is reached as the other of the forward rotation and the reverse rotation in step S13, and the reference is set in step S14. The total rotation amount C may be measured based on the rotation amount. Even in this case, since the total rotation amount C can be measured, the same effect as the above embodiment can be obtained.

(6. Third modified example)
In the embodiment and the first and second modified examples, the control unit 14 executes the step S12 of the inspection program to set the reference rotation amount. Alternatively, the step S12 of the inspection program may be omitted. In this case, the control unit 14 executes the step S14 in the inspection program, and, for example, the absolute value of the rotation amount (angle) of the point P1 when the drive shaft 100 is positively rotated to the specified torque T and a negative value. The sum of the absolute value of the rotation amount (angle) of the point P2 when the drive shaft 100 is reversely rotated to the specified torque T is measured (calculated) as the total rotation amount C. Therefore, also in this case, the same effect as that of the above embodiment can be obtained.

In carrying out the present invention, the present invention is not limited to the above-described embodiments and the respective modified examples, and various modifications can be made without departing from the object of the present invention.

For example, in the above-described embodiment and each modification, the control unit 14 executes the step S15 of the inspection program to calculate and acquire the twist rotation amounts (twist angles) A and B of the rotary shaft member. I chose Instead, the torsional rotation amounts (twisting angles) A and B of the rotary shaft member are measured and stored in advance, and the control unit 14 is stored in advance when executing step S15 of the inspection program. It is also possible to read and acquire the twist rotation amounts (twist angles) A and B of the rotary shaft member. Also in this case, the same effect as that of the above-described embodiment and each of the modified examples can be obtained.

Further, in the above-described embodiment and each modification, the joint inspection method is applied to the drive shaft 100 in which the constant velocity joints 120 and 130 are connected to both ends of the shaft member 110 which is a rotary shaft member. Instead of this, for example, the joint inspection method can be applied to a rotary shaft unit in which the joint is connected to only one end of the rotary shaft member. In this case, the end of the rotary shaft member on the side where the joint is not connected is fixed by the holding portion 11 so as not to rotate.

Further, in the above-described embodiment and the respective modified examples, the Rzeppa type constant velocity joint 120 and the tripod type constant velocity joint 130 connected to the end portion of the shaft member 110 in the drive shaft 100 are the inspection targets. However, the joint provided in the rotary shaft unit is not limited to the constant velocity joint described above, and for example, a double offset joint that can expand and contract along the axial direction, a universal joint that is a non-constant velocity joint, and the like are inspected. It is also possible.

In particular, for a non-constant velocity joint such as a universal joint, as in the above-described embodiment and modifications, the rotary shaft unit is rotated forward and backward until the specified torque T and the specified negative torque T are achieved. , The total amount of rotation C can be measured. Then, the torsional rotation amounts (twisting angles) A and B of the rotary shaft member are calculated and acquired by making the inclination in the twistable region that can be set due to the torsional rigidity, which is a characteristic of the rotary shaft member, constant. , It is possible to read and acquire the amount of twist rotation (twist angle) A and B of the rotary shaft member measured in advance. Therefore, also in the non-constant velocity joint, the same effects as those of the above-described embodiment and each of the modified examples can be expected.

10... Inspection device, 11... Holding part, 12... Motor, 13... Displacement amount sensor, 14... Control part, 15... Load cell, 100... Drive shaft, 110... Shaft member (rotating shaft member), 120... Constant velocity joint ( Joint), 121... Outer ring ball groove, 122... Outer ring, 123... Inner ring ball groove, 124... Inner ring, 125... Ball, 126... Retainer, 127... Shaft part, 130... Constant velocity joint (joint), 131... Outer member , 132... Inner member, 133... Cup-shaped part, 134... Shaft part, 135... Trunnion, A... Twist rotation amount, B... Twist rotation amount, C... Total rotation amount, D... Clearance, D1... Reference clearance, I... Current, P1...Point, P2...Point, Pa...Point, Pb...Point, T...Specific torque

Claims (8)

A joint inspection method for inspecting the quality of a clearance in a rotational direction in a joint which is provided at an end portion of a rotary shaft member, holds the rotary shaft member, and transmits rotation to the rotary shaft member,
Total amount of rotation when one end of the rotary shaft unit including the rotary shaft member and the joint is non-rotatably fixed and the other end of the rotary shaft unit is rotated by forward rotation and reverse rotation until a predetermined specified torque is reached. Total rotation amount measurement process to measure
A twist rotation amount acquisition step of acquiring a twist rotation amount due to twist of the rotation shaft member in the normal rotation and the rotation shaft member in the reverse rotation;
A clearance calculation step of calculating the clearance of the joint by subtracting the twist rotation amount acquired in the twist rotation amount acquisition step from the total rotation amount measured in the total rotation amount measurement step,
A method of inspecting a joint, comprising: a quality determining step of comparing the clearance calculated in the clearance calculating step with a preset reference clearance to determine quality of the clearance. The twist rotation amount acquisition step,
The joint inspection method according to claim 1, wherein the twist rotation amount is calculated and acquired based on a twist characteristic of the rotary shaft member. The twist rotation amount acquisition step,
The relationship between the amount of rotation of the rotary shaft member and the torque input to the rotary shaft member is expressed, and the inclination in the twist region of the rotary shaft member is made constant as the twist characteristic,
The joint inspection method according to claim 2, wherein the tilt rotation amount of the rotary shaft member when the prescribed torque is unloaded from the state in which the prescribed torque is input is calculated and acquired using the inclination. The inclination is
The joint inspection method according to claim 3, which is determined based on a diameter of the rotary shaft member and a length of the rotary shaft member. The total rotation amount measurement step,
A state in which the rotary shaft unit is rotated until one of the forward rotation and the reverse rotation reaches the specified torque is set as a reference rotation amount, and the other of the forward rotation and the reverse rotation becomes the specified torque. The joint inspection method according to any one of claims 1 to 4, wherein the rotating shaft unit is rotated up to and the total amount of rotation is measured. The total rotation amount measurement step,
6. The other end of the rotary shaft unit is rotated by a motor that is rotationally driven by being supplied with the current corresponding to the specified torque, based on a preset relationship between the current and the torque. The joint inspection method according to any one of the above. The total rotation amount measurement step,
When the motor inputs the specified torque to the rotary shaft member and the joint according to the current and stops, it is determined whether the specified torque is input to the rotary shaft member and the joint. Item 7. The joint inspection method according to Item 6. The joint is
The joint inspection method according to any one of claims 1 to 7, which is a constant velocity joint connected to both ends of the rotary shaft member.

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