JPH11230881A - Method and apparatus for testing bending fatigue of gear - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and an apparatus for testing a bending fatigue of gears whereby noises and vibrations at the test are prevented, reliability of test results is increased and test costs are reduced. SOLUTION: A test gear 33 is supported by a gear support means 31. A pair of racks 43 supported by a rack support means 37 at both sides of the test gear 33 are meshed. A load in a longitudinal direction of the racks 43 is repeatedly applied by a load means 19 to between the gear support means 31 and rack support means 37, thereby carrying out a bending fatigue test to the test gear 33. A size of the repeatedly applied load is detected by a load detector 13 and transmitted to a control part 27. The control part 27 compares a load designated for the load means 19 with the detected load and controls the load means 19 so that the detected load becomes the load to be naturally loaded to the test gear 33. Since only a bending load is applied to a gear tooth T of the test gear 33, a highly reliable bending fatigue strength can be obtained without being influenced by a surface pressure strength.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gear bending fatigue test method and a gear bending fatigue test apparatus, and more particularly, to a method of applying several kinds of repetitive bending loads to gear teeth.
The present invention relates to a gear bending fatigue test method and a gear bending fatigue test apparatus suitable for evaluating a gear fatigue strength by creating a −N curve.

[0002]

2. Description of the Related Art Conventionally, as a gear fatigue test method, a power circulation type gear driving test machine 101 as shown in FIG. 3 is generally used. The power circulation type gear driving test machine 101 includes a pair of test gears 103.
The power transmitted by the two pairs A and 103B is used again for driving the apparatus. The flow of the power forms a closed circuit, and the power circulates through the two pairs of test gears 103A and 103B. is there.

That is, referring to FIG. 3, a first gear box 105A and a second gear box 105B rotatably provided in a state in which a pair of test gears 103A and 103B are engaged with each other are arranged in parallel. Box 10
One of test gears 103A of 5A and 105B is connected by a torsion bar 107. The other test gears 103B are connected to each other via a load joint 109 and a torque meter 111.

[0004] A motor 117 is connected to the test gear 103A of the first gear box 105A via a torque meter 113 and a rotation speed conversion gear device 115.

[0005] Therefore, the rotation of the motor 117 is adjusted by the rotation speed converting gear device 115 to adjust the rotation speed of the torque meter 1.
13 through the test gear 10 of the first gear box 105A.
3A, the gear 103A of the second gear box 105B is rotationally driven via the torsion bar 107,
The driving force is transmitted to the test gear 103B meshing with the test gear 103A. The driving force transmitted to the test gear 103B is transmitted to the test gear 103B meshing with the test gear 103A of the first gear box 105A via the load joint 109 and the torque meter 111. Therefore, the driving force circulates in the direction of the arrow in FIG.

[0006]

However, in such a conventional power circulation type gear driving test machine 101,
There is a problem that the noise caused by rotating the test gears 103A and 103B is large, and the test gears 103A and 103B are easily affected by vibration.

Further, since four identical test gears 103 are used in one test, four different test gears must be prepared when the test is performed under different load loads. S to plot fatigue test results against applied load
When performing the fatigue test evaluated by the −N curve, there is a problem that a large number of test gears 103 are required and the test cost is increased.

Further, in the conventional power circulation type gear driving test machine 101, both the bending fatigue strength and the surface pressure fatigue strength of the test gear 103 are to be tested. There is a problem that cannot be evaluated.

SUMMARY OF THE INVENTION An object of the present invention is to pay attention to the above-mentioned conventional technology, and to prevent noise and vibration during a test, increase the reliability of the test result, and reduce the test cost. It is an object of the present invention to provide a gear bending fatigue test method and a gear bending fatigue test apparatus that can perform the test.

[0010]

SUMMARY OF THE INVENTION In order to achieve the above object, a method for testing the bending fatigue of a gear according to the present invention comprises:
In a gear bending fatigue test method in which a bending load is repeatedly applied to the teeth of a test gear, a pair of racks are meshed on both sides with the test gear interposed therebetween, and the longitudinal length of the rack is set between the pair of racks and the test gear. Wherein a load in a direction along the direction is repeatedly applied, and a bending load is repeatedly applied to the teeth of the test gear.

Therefore, the test gear is subjected to a gear bending fatigue test by a pair of racks meshing on both sides of the rack, without rotating, and only the specific teeth meshing with the rack are repeatedly subjected to a bending load. Is performed.

According to a second aspect of the present invention, there is provided a gear bending fatigue test apparatus according to the first aspect.
When performing a bending fatigue test by changing the magnitude of the repetitive bending load applied to the teeth of the test gear, teeth that have not yet been tested on the same test gear are meshed with the rack. Things.

Therefore, it is possible to perform a plurality of bending fatigue tests under different conditions with one test gear.

According to a third aspect of the present invention, there is provided a gear bending fatigue test method according to the first or second aspect, wherein the test gear and / or the rack have unnecessary teeth so as to mesh with one tooth. It is characterized by being excised.

Therefore, only one tooth of the test gear and the rack surely mesh with each other, and an accurate bending load can be applied to this tooth to obtain a highly reliable bending fatigue strength.

According to a fourth aspect of the present invention, there is provided a gear bending fatigue test apparatus comprising: a gear supporting means for detachably supporting a test gear for performing a bending fatigue test; a pair of racks meshing on both sides with the test gear interposed; Rack support means for supporting a pair of racks, loading means for loading a load relatively along the longitudinal direction of the rack between the rack support means and the gear support means, and a predetermined timing And a control unit for performing control so as to repeatedly operate with a load.

Therefore, the test gear supported by the gear supporting means is placed in a state in which it is supported by the rack supporting means and meshes with a pair of racks located on both sides of the test gear with the test gear held therebetween. The test gear is subjected to a bending fatigue test by repeatedly applying a load between the means and the rack supporting means by a loading means for applying a load in a direction along the longitudinal direction of the rack.

According to a fifth aspect of the present invention, there is provided the gear bending fatigue test apparatus according to the fourth aspect.
The loading means has a load detector that detects a load actually loaded, and the control unit is configured to match the load detected by the load detector with a command load commanded to the loading means. Controlling the loading means;
It is characterized by the following.

Therefore, the magnitude of the repetitive load applied to the test gear by the loading means is detected by the load detector and transmitted to the control unit, so that the control unit determines the load instructed by the loading means and the detected load. And controlling the loading means so that the detected load is a load that should be originally loaded on the test gear.

According to a sixth aspect of the present invention, there is provided a gear bending fatigue test apparatus according to the fourth or fifth aspect, wherein the test gear and / or the rack are formed with unnecessary teeth so that the test gear and / or the rack mesh with one tooth. Being resected,
It is characterized by the following.

Accordingly, only one tooth of the test gear and the rack are reliably engaged with each other, and an accurate bending load acts on this one tooth, so that a highly reliable bending fatigue strength can be obtained.

According to a seventh aspect of the present invention, in the gear bending fatigue test apparatus according to the fourth, fifth or sixth aspect, the change in distance between the gear supporting means and the rack supporting means is measured. When the change in the distance exceeds a preset range at the time of loading by taking a change in the distance from the measurement means, the control unit includes:
Being adapted to stop loading of the load,
It is characterized by the following.

Therefore, by detecting the start of breakage of the teeth of the test gear by the measuring means and stopping the loading of the load, the gear bending fatigue test can be performed safely and accurately.

According to an eighth aspect of the present invention, in the gear bending fatigue test apparatus according to the fourth, fifth, sixth or seventh aspect, at least one of the test gear and the rack changes a meshing depth. And the meshing portion can be automatically aligned at the time of loading.

Therefore, the meshing condition of the two racks with the test gear becomes uniform, the same test load acts on the teeth on both sides of the test gear, and a highly reliable bending fatigue strength can be obtained.

[0026]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIGS. 1 and 2 show a gear bending fatigue test apparatus 1 according to the present invention.

Referring to FIG. 1, a servo hydraulic testing machine 3 is used in the gear bending fatigue test apparatus 1. In the servo hydraulic testing machine 3, a pair of tie bars 7 are erected upward near the left and right ends of the upper surface of the base 5. An upper plate 9 is provided so as to connect the upper ends of the pair of tie bars 7, and upper and lower nuts 11, 1
1 is fixed so that the height can be adjusted. An upper head 15 is attached to the lower surface of the upper plate 9 via a load cell 13 as an example of a load detector.

A hydraulic actuator 19 as an example of loading means is provided inside the base 5 with the piston rod 21 facing upward.
A lower head 23 is attached to the upper side of the first head 1. The hydraulic actuator 19 is operated by a hydraulic control valve 29 controlled by a control unit 27. The load cell 13 is connected to the control unit 27.

Referring to FIG. 2, a pair of front and rear gear support blocks 31, which are examples of gear support means, are detachably mounted on the upper surface of the lower head 23 by bolts 25, and the position in the left and right direction in FIG. Near the upper ends of the pair of gear support blocks 31, a test gear 33 for performing a bending fatigue test is provided with front and rear gear support blocks 3.
A support shaft 35 for supporting between the two is detachably provided.

On the lower surface of the upper head 15, a pair of left and right rack support blocks 3 as an example of rack support means is provided.
7 is provided downward by a bolt 17, and its lower end is connected to each other by fixing a connecting member 39 with a bolt 41. A pair of racks 43 for applying a repeated load to the test gear 33 are attached to the inner surfaces of the pair of rack support blocks 37 by bolts 45, respectively.

A liner 47 for adjusting the position in the longitudinal direction and the distance between both racks is appropriately inserted between both ends and the rear surface of the rack 43 in the longitudinal direction and the rack support block 37, and the position of the test gear 33 in the lateral direction is adjusted. Along with the adjustment, adjustment can be made so that the test gear 33 and the rack 43 mesh properly.

Here, as shown in FIG. 2, since the teeth T of the test gear 33 are cut by wire cutting every other tooth, the two teeth do not mesh with the rack 43 at the same time. The load can be repeatedly applied only to the vehicle.

Referring again to FIG. 1, the mounting flange portion 37A of the rack support block 37 and the gear support block 3
Measuring means 50 for measuring a change in the distance between them is provided between the first mounting flange portions 31A. The measuring means 50 includes a fixed block 51 attached to the side surface of the mounting flange 37A of the rack support block 37, and a bar 5 attached to the fixed block 51.
3. Non-contact displacement meter 55 attached to the tip of the bar 53, and a measuring device 5 paired with the non-contact displacement meter 55
It consists of seven. The non-contact displacement meter 55 faces the upper surface of the mounting flange portion 31A of the gear support block 31 in FIG.
Mounting flange 31 of gear support block 31 with respect to A
In FIG. 1A, the displacement of the upper surface, that is, the change in the distance between the mounting flange portion 37A of the rack support block 37 and the mounting flange portion 31A of the gear block 31 is measured.

The bar 53 is attached to the fixed block 51 so as to be vertically movable in FIG.
Thus, the position of the non-contact displacement meter 55 with respect to the upper surface in FIG. 1 of the mounting flange portion 31A of the gear support block 31 can be appropriately set.

The output of the measuring device 57, that is, the output of the measuring means 50 is taken into the control section 27, and when the output of the measuring means 50 exceeds a preset range, the hydraulic control valve 29 or a not shown. Close the separately provided switching valve,
The supply of the pressure oil to the hydraulic actuator 19 is stopped.

With the above configuration, the test gear 33 is connected to the support shaft 3.
5 and adjust the position and spacing of the rack 43 with the liner 47 to accurately engage and fix the rack 43 on both sides of the test gear 33, and loosen the set screw 59 to move the bar 53. The position of the non-contact displacement meter 55 is adjusted and set so that a measurement value serving as a predetermined reference can be obtained from the measuring device 57. Next, the hydraulic actuator 19 is operated by the control of the control unit 27 so as to apply a load to the rack support block 37 in a direction to relatively raise or lower the gear support block 31, that is, a direction along the longitudinal direction of the rack 43. At this time, since the rack 43 meshes with both sides of the test gear 33, the test gear 33 does not rotate and the rack 43 does not substantially move.

At this time, the magnitude of the load is
3 and is fed back to the control unit 27. The control unit 27 compares the signal from the load cell 13 with the command load, controls the supply pressure to the hydraulic actuator 19 via the hydraulic control valve 29, and controls the command load and the measured load to be equal. The loading time is controlled by the control unit 27. When a relatively short predetermined time elapses, the load is returned to almost zero, and the same upward or downward load is repeatedly applied again.

When the teeth T of the test gear 33 start to be broken in this way, the gear supporting block 3
1 moves up or down. This movement is detected by the non-contact displacement meter 55, and when the value exceeds a predetermined range, the control unit 27 stops the supply of the pressurized oil to the hydraulic actuator 19 and ends the first bending fatigue test. I do.
Next, another tooth T of the test gear 33 is rotated so as to mesh with the rack 43, and a bending fatigue test is performed by repeatedly changing the value of the load.

From the above results, since the bending fatigue test is performed by repeatedly applying the load by the pair of racks 43 without rotating the test gear 33, noise and vibration during the test can be prevented.

Further, a rack 43 on which a repeated load is loaded
Since only one tooth of the test gear 33 meshes with the test gear 33, the bending fatigue test can be performed with a single test gear 33 for several kinds of loads by changing the teeth T of the test gear 33 to be meshed. Therefore, it is not necessary to manufacture a large number of test gears 33, and the test cost can be reduced.

Further, since the repetitive load is applied by the servo hydraulic testing machine 3, there is little change in the load, and there is no influence of the surface pressure strength, so that a highly reliable bending fatigue test can be performed.

The present invention is not limited to the above-described embodiment, but can be embodied in other modes by making appropriate changes. That is, in the above-described embodiment, the teeth T of the test gear 33 are cut every other tooth. Alternatively, the teeth t of the rack 43 may be cut every other tooth.

When the teeth t of the rack 43 for repeatedly loading the test gear 33 are deformed, the amount of extension of the piston rod 21 is changed or the upper head 1 is moved.
The position of the meshing teeth of the rack 43 may be changed by changing the position of the upper plate 9 that supports the rack 5.

Furthermore, in the above-described embodiment, the non-contact displacement meter 55 attached to the rack support block 37 is used to connect the gear support block 31 as the gear support means and the rack support block 37 as the rack support means. The example in which the start of cutting of the tooth T is detected by measuring the change in the distance of the tooth T and the supply of the pressure oil to the hydraulic actuator 19 is automatically stopped by the start of the cutting, has been described. The supply of the pressure oil to the hydraulic actuator 19 may be automatically or artificially stopped by detecting or knowing the cut of the tooth T by other means or the eyes of the operator. For the measurement, various measuring means other than the non-contact displacement meter 55 can be adopted.

Further, in the above-described embodiment, the engagement between the test gear 33 and the rack 43 is changed to the liner 47.
In this case, at least one of the test gear 33 and the rack 43 is moved by a predetermined amount in a direction in which the meshing depth of the test gear 33 and the rack 43 is changed, that is, in a horizontal direction perpendicular to the vertical direction in FIG. If it is freely supported, the test gears 33 can be
Is self-aligned, the meshing state on both the left and right sides of the test gear 33 becomes uniform, the same test load acts on the teeth on both sides of the test gear 33, and a highly reliable test can be performed.

[0047]

As described above, in the gear bending fatigue test method according to the first aspect of the present invention, the rack is meshed on both sides with the test gear interposed, and the rack is interposed between the pair of racks and the test gear. The test gear does not rotate because the gear bending fatigue test is performed by repeatedly applying a load along the longitudinal direction. For this reason, it is possible to prevent noise or vibration from occurring during the test. Also,
A highly reliable bending fatigue test can be performed without being affected by the surface pressure strength.

In the gear bending fatigue test method according to the second aspect of the present invention, after performing a bending fatigue test of the test gear under a certain amount of repetitive load, the teeth of the test gear meshing with the pair of racks are still in the same test gear. Since the bending fatigue test can be further performed in place of the teeth not used in the test, it is possible to perform the bending fatigue test under different conditions such as several kinds of loads with one test gear. Thereby, the cost required for the test can be reduced.

In the gear bending fatigue test method according to the third aspect of the present invention, only one tooth of the test gear and the rack reliably mesh with each other. High bending fatigue strength can be obtained.

In the gear bending fatigue testing apparatus according to the fourth aspect of the present invention, the test gear is supported by the gear supporting means, and a pair of racks supported by the rack supporting means on both sides of the test gear are engaged with each other, thereby supporting the gear. The test gear does not rotate since the bending fatigue test of the test gear is performed by applying a load along the longitudinal direction of the rack by the loading means between the means and the rack supporting means. For this reason, it is possible to prevent noise and vibration from occurring during the test, and it is possible to perform a highly reliable bending fatigue test that is not affected by the surface pressure strength.

In the gear bending fatigue test apparatus according to the fifth aspect of the present invention, the magnitude of the repetitive load applied to the test gear by the loading means is detected by the load detector and transmitted to the control unit. By comparing the load commanded to the loading means with the detected load, the loading means can be controlled so that the detected load is the load that should be originally loaded on the test gear.

In the gear bending fatigue test apparatus according to the sixth aspect of the present invention, since only one tooth of the test gear and the rack are reliably engaged, a highly reliable bending fatigue strength can be obtained.

In the gear bending fatigue test apparatus according to the seventh aspect of the present invention, a fatigue test can be performed safely and accurately by detecting the start of breakage of the teeth of the test gear by measuring means and stopping the loading.

In the gear bending fatigue test apparatus according to the eighth aspect of the invention, the meshing portion is automatically aligned at the time of loading, and the meshing state of the two racks with the test gear is made uniform to apply a test load equal to the teeth on both sides of the test gear. Can work,
Highly reliable bending fatigue strength can be obtained.

[Brief description of the drawings]

FIG. 1 is an overall view showing an embodiment of a gear bending fatigue test apparatus according to the present invention.

FIG. 2 is an enlarged view of a meshing portion of the gear bending fatigue test device shown in FIG.

FIG. 3 is an overall view showing a conventional power circulation type gear driving test machine.

[Explanation of symbols]

 1 Gear Bending Fatigue Test Apparatus 13 Load Cell (Load Detector) 19 Hydraulic Actuator (Loading Means) 27 Controller 31 Gear Support Block (Gear Supporting Means) 33 Test Gear 37 Rack Support Block (Rack Supporting Means) 43 Rack 50 Measuring Means 55 Non-contact displacement meter 57 measuring device T tooth

Claims (8)

[Claims] In a gear bending fatigue test method in which a bending load is repeatedly applied to teeth of a test gear, a pair of racks are meshed on both sides of the test gear with the test gear interposed therebetween. A gear bending fatigue test method, comprising repeatedly applying a load in the direction along the longitudinal direction of the rack between the test gears to repeatedly apply a bending load to the teeth of the test gear. 2. When performing a bending fatigue test by changing the magnitude of a repetitive bending load applied to the teeth of the test gear,
The gear bending fatigue test method according to claim 1, wherein teeth of the same test gear that have not been tested are meshed with the rack. 3. The test gear and / or rack according to claim 1, wherein
The gear bending fatigue test method according to claim 1 or 2, wherein unnecessary teeth are cut off so as to mesh with one tooth. 4. A gear supporting means for detachably supporting a test gear for performing a bending fatigue test, a pair of racks meshing on both sides of the test gear, and a rack supporting means for supporting the pair of racks. Loading means for loading a load between the rack supporting means and the gear supporting means in a direction along the longitudinal direction of the rack; and a control unit for controlling the loading means to operate repeatedly at a predetermined timing and load. And a gear bending fatigue test apparatus characterized by comprising: 5. The load means has a load detector for detecting a load actually loaded, and the control unit comprises:
The gear bending fatigue test apparatus according to claim 4, wherein the load means is controlled so that the load detected by the load detector matches a command load instructed to the load means. 6. The test gear and / or rack comprises:
The gear bending fatigue test device according to claim 4 or 5, wherein unnecessary teeth are cut off so as to mesh with one tooth. 7. A measuring device for measuring a change in the distance between the gear supporting device and the rack supporting device, wherein the control unit captures the change in the distance from the measuring device and measures the distance during loading. 7. The gear bending fatigue test apparatus according to claim 4, wherein when the change exceeds a predetermined range, the loading of the load is stopped. 8. The test gear and the rack, wherein at least one of the test gear and the rack is supported so as to be movable by a predetermined amount in a direction in which a meshing depth is changed, and a meshing portion is capable of self-aligning during loading. Item 4. A gear bending fatigue test apparatus according to item 4, 5, 6, or 7.