JP2015072206A - Load power history confirmation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a load power history confirmation method capable of measuring torque easily without requiring a sensor target, a sensor and the like.SOLUTION: Provided is the load power history confirmation method for determining load power excessively applied to a bar-shape object S. Relation between load and displacement on a bar-shaped object S as a product to which load power exceeding elastic limit is inputted, and relation between load and displacement on a bar-shaped object S as an unused product, are compared. Therefore, the load power excessively inputted, is determined.

Description

  The present invention relates to a load force history confirmation method that enables confirmation of an excessive input torque history of a shaft that is a rod-like body, for example, a constant velocity universal joint shaft.

  A drive shaft as a drive wheel axle for transmitting the power of an automobile engine to wheels is composed of an intermediate shaft and a constant velocity universal joint disposed at both axial ends of the intermediate shaft. In the drive shaft, one constant velocity universal joint is connected to a differential, and the other constant velocity universal joint is connected to an axle. That is, the drive shaft is incorporated in a drive system that transmits engine power to the wheels, and the engine power is finally transmitted to the wheels by the drive shaft.

  Thus, the constant velocity universal joint of a drive shaft used in an automobile is required to have a strength that can sufficiently withstand an excessive torque generated when the automobile is suddenly started or suddenly accelerated. For this reason, conventionally, there is a measuring method and a measuring device for measuring a shaft torque acting on a drive shaft (Patent Document 1).

  In the measuring apparatus described in Patent Document 1, a magnetically detectable mark such as a magnetic pole is attached to an outer joint member (outer ring) of a constant velocity universal joint, and the outer joint of each constant velocity universal joint. Sensors are respectively arranged at positions corresponding to the members. And the mark (mark) corresponding to each is detected by each sensor. That is, by measuring the number of pulses of the rotation pulse signal between the detection pulse of one (outboard side) sensor and the detection pulse of the other (inboard side) sensor, the twist angle generated in the drive shaft is measured. This torsion angle is calculated to determine the shaft torque.

JP 2007-93452 A

  In the measuring apparatus described in Patent Document 1, a sensor target is provided on the outer joint member (outer ring) of each constant velocity universal joint, and a sensor arrangement for receiving a rotation pulse signal emitted from the sensor target is provided. There is a need to,

  For this reason, in the thing of the said patent document 1, while the number of parts was many and cost became high, the assembly operation time became long.

  SUMMARY OF THE INVENTION In view of the above problems, the present invention provides a load force history confirmation method capable of easily measuring an excessively input torque exceeding an elastic limit without requiring a sensor target or a sensor.

  The load force history check method of the present invention is a load force history check method for obtaining a load force excessively input to a rod-like body, and the load and displacement in a rod-like body as a product to which a load force exceeding an elastic limit is inputted. Is compared with the relationship between the load and displacement in the rod-shaped body as an unused product, and the excessively input load force is obtained.

  According to the load force history confirmation method of the present invention, a load force exceeding the elastic limit is input (loaded) to a rod-shaped body as a product. Generally, when a force exceeding the elastic limit, that is, a force in the plastic region (a force for plastic deformation) is applied to the material, the elastic limit of the material is improved. That is, dislocations are proliferated with plastic deformation, which is unevenly distributed and becomes an obstacle to dislocations that move by being entangled with each other. Further, since the movement of dislocations is further suppressed, deformation resistance increases. Therefore, once a material has undergone plastic deformation, it exhibits elastic behavior within its stress range, and the yield point (starting point of plastic deformation) is higher than that of the original material, making it less likely to cause plastic deformation and reducing elongation at break. So-called hard properties. Here, the yield point is the magnitude of the force when the deformation of the object suddenly increases and cannot be restored when a force is applied to the object.

  Therefore, by comparing the relationship between the load and displacement of the rod-shaped body as a product to which a load force exceeding the elastic limit is input, and the relationship between the load and displacement of the rod-shaped body as an unused product, an excessive input The history of torque (input torque to products exceeding the elastic limit) can be confirmed.

  The input load force can be at least one of torsional force, tensile force, compressive force, and bending force. Further, the load force may be a torsion force input using a static torsion tester, the load may be a load torque, and the displacement may be a twist angle.

  The rod-shaped body may be a solid shaft connected to the constant velocity universal joint, a hollow shaft connected to the constant velocity universal joint, or a long stem of the constant velocity universal joint.

  According to the load force history confirmation method of the present invention, for example, when confirming a drive shaft, the shaft used as an actual vehicle test product or a market running product is removed, and the load force is input to this shaft (rod-like body). Then, you can check the input history of overpower. That is, an excessively input force can be easily obtained without using a sensor target or a sensor.

  As a load applied to the rod-shaped body (shaft member), there are a bending force, a twisting force, an axial force, and a combination thereof. For this reason, in this load force history confirmation method, the input load force may be any one of torsional force, tensile force, compressive force, and bending force, so the load applied to the rod-shaped body (shaft member) (load) Depending on the type of force), an excessively loaded force can be obtained.

  The rod-like body can be a solid shaft, a hollow shaft, or a long stem, and has a wide application range, and this load force history confirmation method is excellent in versatility.

It is a process simplification block diagram of this invention. It is sectional drawing of a drive shaft. FIG. 3 is a plan view of an intermediate shaft of the drive shaft of FIG. 2. It is a simplified diagram of a static torsion tester. It is a graph which shows the relationship between a twist angle and load torque. It is a simplified diagram of a tensile compression tester. The relationship between load and strain is shown, (a) is a new graph, (b) is a graph showing an unloading point, and (c) is a graph when re-loaded.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. This load force history confirmation method is for confirming an excessive input torque history of a shaft that is a rod-shaped body S, for example, a constant velocity universal joint shaft 65 (see FIGS. 2 and 3). The relationship between the load and displacement in the rod-shaped body S as an input product is compared with the relationship between the load and displacement in the rod-shaped body S as an unused product.

  By the way, when an external force such as a tensile force is applied to the rod-shaped body S, the relationship between stress (σ) and strain (ε) as shown in FIG. That is, elastic deformation occurs up to the Y1 point (yield point), and when this Y1 point is exceeded, a plastic deformation region is obtained. As shown in FIG. 7 (b), when the rod-shaped body S is loaded after exceeding Y1 point to Y2 point and then unloaded, this unloaded point is defined as C. Then, if an external force such as a tensile force is again applied from point C to point Y2 beyond point Y1, this rod-shaped body S has a yield point Y2 as shown in FIG. 7 (c). ing. That is, when a force in the plastic region is applied to the material, the elastic limit (yield point) of the material is improved. The present invention utilizes this principle.

  As a device for applying an external force, a static torsion tester 1 shown in FIG. 4 is used. That is, the torsional force is used as the load force in this case. The static torsion tester 1 includes a base 2 and a pair of driving bodies 3 and 4 disposed on the base 2. Each driving body 3, 4 has rotary actuators 5, 6 as a driving source, and chuck members 7, 8 linked to the driving shafts of the rotary actuators 5, 6. The driver 4 can be driven or fixed depending on the setting at the time of the test.

  Further, guide rails 9 and 10 are provided on the base 2, and the driving bodies 3 and 4 can approach and separate from each other along the guide rails 9 and 10. A torque meter 11 is attached to the driving body 3.

  As shown in FIG. 2, the drive shaft is connected to the fixed constant velocity universal joint T1 on the outboard side, the sliding constant velocity universal joint T2 on the inboard side, and the constant velocity universal joints T1 and T2. And a shaft (constant velocity universal joint shaft) 65. The side that is outside the vehicle when assembled in a vehicle such as an automobile is the outboard side (left side of the drawing), and the side that is inside the vehicle when assembled in a vehicle such as an automobile is called the inboard side (right side of the drawing). .

  The fixed type constant velocity universal joint T1 is paired with an outer ring 53 as an outer member (outer joint member) in which a plurality of track grooves 52 are formed on an inner spherical surface 51, and a track groove 52 of the outer ring 53 on an outer spherical surface 54. A plurality of balls that transmit torque by being interposed between an inner ring 56 as an inner member (inner joint member) formed with a plurality of track grooves 55, and between a track groove 52 of the outer ring 53 and a track groove 55 of the inner ring 56. 57, and a cage 58 that holds the ball 57 interposed between the inner spherical surface 51 of the outer ring 53 and the outer spherical surface 54 of the inner ring 56.

  The inner ring 56 has a hole inner diameter 56a and a male spline 65a at one end of the shaft 65 coupled by spline fitting, so that torque transmission with the shaft 65 becomes possible. Further, a retaining ring 60 for retaining is attached to the male spline 65a of the shaft 65.

  The outer ring 53 includes a mouse part 53a and a stem part (shaft part) 53b. The mouse part 53a has a bowl shape opened at one end, and a plurality of track grooves 52 extending in the axial direction are circularly formed on the inner spherical surface 51 thereof. It is formed at equal intervals in the circumferential direction.

  The opening of the mouse part 53 a is covered with a boot 70. The boot 70 includes a large diameter portion 70a, a small diameter portion 70b, and a bellows portion 70c that connects the large diameter portion 70a and the small diameter portion 70b. The large-diameter portion 70a is externally fitted to the opening of the mouse portion 53a, and the band 111 is fastened in this state. The small-diameter portion 70b is externally fitted to the boot mounting portion 65b of the shaft 65, and the band 111 is fastened in this state. Yes.

  The sliding type constant velocity universal joint T2 includes an outer ring 83 as an outer joint member in which a plurality of linear track grooves 82 are formed in an axial direction on a cylindrical inner diameter surface 83a, and a plurality of spherical outer diameter surfaces 86a. An inner ring 86 as an inner joint member in which a linear track groove 85 is formed in the axial direction; a ball 87 that is interposed between the track groove 82 of the outer ring 83 and the track groove 85 of the inner ring 86; And a cage 88 that holds the ball 87 interposed between an inner diameter surface of the inner ring 83 and an outer diameter surface of the inner ring 86.

  The outer ring 83 includes a cup portion 90 in which the track groove 82 is formed on the inner diameter surface 83 a and a stem portion 91 that protrudes from the bottom wall of the cup portion 90. The inner ring 86 has a hole inner diameter 86b and a male spline 65c at the other end of the shaft 65 coupled by spline fitting so that torque can be transmitted to the shaft 65. A retaining ring 61 for retaining is attached to the male spline 65d of the shaft 65.

  The opening of the cup 90 is covered with the boot 100. The boot 100 includes a large diameter portion 100a, a small diameter portion 100b, and a bellows portion 100c that connects the large diameter portion 100a and the small diameter portion 100b. The large diameter portion 100a is externally fitted to the opening of the cup portion 90, and the band 111 is fastened in this state, and the small diameter portion 100b is externally fitted to the boot mounting portion 65d of the shaft 65, and the band 111 is fastened in this state. Yes.

  As shown in FIG. 3, the shaft 65 is a solid body and includes a shaft main body 92 and the male splines 65 a and 65 c provided at both ends of the shaft main body 92. The male splines 65a and 65c are formed in the large end portion of the end portion that is connected to the shaft main body 92 through tapered portions 93a and 93c that expand from the main body side toward the end portion side.

  The shaft main body 92 is formed with boot mounting portions 65b and 65d. In this case, a large diameter portion 94b is formed on the male spline 65c side of the shaft main body 92, and a circumferential groove 95b is formed in the large diameter portion 94b. The boot mounting part 65b is comprised by providing. Further, a large diameter portion 94d is formed on the male spline 65c side of the shaft body 92, and a circumferential groove 95d is provided in the large diameter portion 94d, thereby forming a boot mounting portion 65d. In addition, taper 96b, 97b, 96d, 97d is provided in the both ends of large diameter part 94b, 94d. The male splines 65a and 65c are formed with circumferential grooves 98 and 99 in which the retaining rings 60 and 61 are mounted, respectively.

  Next, the load force history confirmation method of the present invention will be described with reference to FIG. A shaft 65 of a used product (an actual vehicle test product, a market running product, etc.) is mounted on the static torsion tester 1 (see FIG. 4), and a twisting force is applied to the shaft 65 (step S1). Then, the relationship between the load (load) and the displacement is calculated (step S2). In this case, the waveform is as shown by the alternate long and short dash line in FIG. The load is a load torque (kN · m), which can be calculated by a torque meter, and the displacement is a torsion angle, which can be calculated by a rotary actuator.

  Further, an unused (new) shaft 65 is also mounted on the static torsion tester 1 and a twisting force is applied to the shaft 65 to calculate a relationship between a load (load) and displacement. . In this case, the waveform shown by the solid line in FIG. Then, the relationship between the load and displacement in the unused shaft 65 and the load and displacement in the used shaft 65 are compared (step S3).

  In FIG. 5, the used product (excess torque input product) indicated by the alternate long and short dash line has a twist angle rising from around 15 °. This is due to the processing at the time of graph creation. As long as the shaft 65 having the same product and the same rigidity is used within the elastic limit torque, a new load and a used load have similar load torque diagrams, and the two are almost the same. However, once a torque exceeding the elastic limit is applied, the elastic limit is improved by yielding, the elastic limit of the new (unused) and used (used) does not match, and the load torque diagrams of both are off. . Therefore, the excessive input torque can be estimated by moving the excessive input torque product (one-dot chain line) in parallel with the new load torque diagram (solid line). (By shifting the load torque diagram of the product used indicated by the one-dot chain line by 15 ° in parallel, it can be matched with the new product indicated by the solid line.) That is, the excessive input torque product is twisted by 15 ° compared to the new product. It can be inferred that the plastic deformation has occurred. Further, when a torque that greatly exceeds the bullet limit is applied, an excessive input torque can be estimated without overlapping with a new article. In this case, the inflection point between the straight line area and the curve area becomes an excessive input torque.

  Therefore, as can be seen from FIG. 5, the elastic limit (yield point) is XkN · m for the unused product (the one to which the torsional force is applied for the first time), whereas the elastic limit (yield) is used for the used product. Point) is YkN · m. For this reason, it can be seen that an excessive input torque of YkN · m was input to the product used. That is, it can be seen that there was an input history of YkN · m. If the elastic limit of the product used is XkN · m, the torsional force in the plastic deformation region was not loaded.

  By the way, the load force to the shaft 65 is not limited to the torsional force, and may be a tensile force using a tensile compression tester shown in FIG. 6 or a compressive force. The tensile / compression testing machine shown in FIG. 6 has a load detector 30 (load cell) attached to the top of a cross head (a vertical movement member disposed in a horizontal direction on a frame not shown). The upper chuck member 31 that grips the upper portion of the shaft 65 is connected to 30 and the upper chuck member 31 is suspended from the cross head. Further, a lower chuck member 32 that holds the lower portion of the shaft is erected on a base (not shown) on which a frame body (not shown) is erected.

  For example, the cross head moves up and down by driving a screw shaft arranged on the frame with a motor (not shown). In this case, if the cross head is raised, a tensile force is applied to the shaft 65, and if the cross head is lowered, a compressive force is applied to the shaft 65.

  The displacement amount is detected by the displacement meter 33 directly attached to the shaft 65, and the load is detected by the load cell 30. The displacement amount may be detected by the amount of vertical movement of the cross head. For this reason, if the load force is a tensile force, it is excessive by comparing the relationship between the load (tensile load) and displacement in the unused shaft and the load (tensile load) and displacement in the shaft 65 that is a used product. You can check the input history of tensile force. If the load force is a compressive force, it is excessive by comparing the relationship between the load (compression load) and displacement in the unused shaft 65 and the load (compression load) and displacement in the used shaft 65. You can check the input history of compression force.

  The load force on the shaft 65 may be a bending force in addition to a twisting force, a tensile force, and a compressive force. In the case of this bending force, a bending tester can be used. A bending test is a test that measures the behavior of a material subjected to a bending load. The test piece is supported by two support rods and a load is applied to the center, and a stress-strain diagram can be formed. .

  For this reason, the input history of the excessive bending load force can be confirmed by comparing the relationship between the load (bending load) and displacement in the used shaft and the load (bending load) and displacement in the used shaft.

  By the way, in this embodiment, the shaft 65 is a solid shaft, but may be a hollow shaft.

  In addition, a member having a long shaft portion (long stem) may be used as an outer joint member of the constant velocity universal joint. In order to make the lengths of the left and right drive shafts equal, the inboard side outer joint member of the drive shaft on one side is made a long stem, and this long stem is rotatably supported by a rolling bearing. The length of the long stem varies depending on the vehicle type, but is approximately 300 to 400 mm. Therefore, this long stem may be a rod-shaped body (shaft) of the present invention, and the load force history of this long stem may be confirmed.

  In the load force history confirmation method of the present invention, for example, when confirming a drive shaft, the shaft used as an actual vehicle test product or a market running product is removed, and the load force is input to this shaft (rod-like body). The input history of overpower can be confirmed. That is, an excessively input force can be easily obtained without using a sensor target or a sensor.

  The load applied to the rod-shaped body (shaft member) is a bending force, a torsional force, an axial force, and a combination thereof. For this reason, in this load force history confirmation method, the input load force may be any one of torsional force, tensile force, compressive force, and bending force, so the load applied to the rod-shaped body (shaft member) (load) Depending on the type of force), an excessively loaded force can be obtained.

  The rod-shaped body S can be a solid shaft, a hollow shaft, or a long stem, has a wide application range, and this load force history confirmation method is excellent in versatility.

  As described above, the embodiment of the present invention has been described. However, the present invention is not limited to the above-described embodiment, and various modifications are possible. As a product (bar-shaped body) using this load force history confirmation method, a drive shaft It is not restricted to the intermediate shaft of this type, a long stem of a constant velocity universal joint, etc., but can be used for a shaft used in various devices and mechanisms.

1 Testing Machine 65 Constant Velocity Universal Joint Shaft S Rod Body T1 Constant Velocity Universal Joint T2 Constant Velocity Universal Joint

Claims (6)

A load force history confirmation method for obtaining an excessive load force input to a rod-shaped body,
An excessive input was made by comparing the relationship between the load and displacement of the rod-shaped body as a product to which a load force exceeding the elastic limit was input and the relationship between the load and displacement of the rod-shaped body as an unused product. A load force history confirmation method characterized by obtaining a load force.   The load force history check method according to claim 1, wherein the input load force is at least one of torsional force, tensile force, compressive force, and bending force.   The load force history confirmation method according to claim 1, wherein the load force is a torsion force input using a static torsion tester, the load is a load torque, and the displacement is a twist angle.   The negative load force history confirmation method according to any one of claims 1 to 3, wherein the rod-shaped body is a solid shaft connected to a constant velocity universal joint.   The load force history confirmation method according to any one of claims 1 to 3, wherein the rod-shaped body is a hollow shaft connected to a constant velocity universal joint.   The load force history confirmation method according to any one of claims 1 to 3, wherein the rod-shaped body is a long stem of a constant velocity universal joint.

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