JPH08178815A - Loader for abrasion test machine - Google Patents

Abstract

PURPOSE: To eliminate fluctuation in the abrasion test using an abrasion test machine Lambourn by enhancing the loading accuracy especially in a low load region. CONSTITUTION: This is a loader 2 for abrasion test machine, in which a load is applied to a sample 3 in order to press the sample 3 against a grinding wheel 5, and which comprises a load cell 11 for detecting the load, a sample fixing part 4 provided at one end part of the load cell 11 through a coupling shaft 10, and an air cylinder 12 having a piston rod 13 for applying a load coupled to the other end of the load cell 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a load applying device for a Lambourn abrasion tester, which is also defined by JIS, in an abrasion tester for elastic materials such as vulcanized rubber.

[0002]

2. Description of the Related Art A conventional load applying device for a Lambourn abrasion tester has a structure as shown in FIG.
The test sample 02 made of a ring-shaped vulcanized rubber is horizontally pressed against the outer peripheral surface of the disk-shaped polishing wheel 03 with a predetermined load generated by the load cell 010 to detect the load. And, pulley 08, 08 'and slide bearing 0
In order to eliminate the effects of the sliding resistance of 9 and the bouncing of the test sample 02, counterbalance weights 04 and 0
I try to balance it at 4 '. During the test while rotating the grinding wheel 03 and the sample 02, the sample 02
In order to prevent the heavy jumping,
An oil damper 07 for absorbing vibration is installed in the lower part of the. The air cylinder 05 does not act when a load is applied, and when the test is completed and the sample 02 is separated from the grinding wheel 03, the piston rod 06 is projected and used.

Another conventional technique is shown in FIG. 4 proposed by the present applicant in Japanese Utility Model Laid-Open No. 61-184952. However, all such conventional techniques have the following problems.

[0004]

All of the prior arts have the following problems with respect to the accuracy of the load applied in the low load range. In the prior art shown in FIG. 3, the friction resistance of the pulleys 08 and 08 'for the wire holding the weight 01 and the counterbalance weights 04 and 04', the slide bearing 09 and the rotary shaft 011 of the mounting portion of the sample 02 is insensitive. Therefore, the amount of wear of the sample 02 varies. Next, in the conventional technique shown in FIG. 4, the moving speed of the sample 015 until the outer peripheral surface of the sample 015 contacts the outer peripheral surface of the grinding wheel 016 when a load is applied is controlled by the air cylinder 017. There is no. However, sample 015
Since the weight is applied by the weight 018 after the outer peripheral surface of the contacting the outer peripheral surface of the grinding wheel 016, the conventional technique shown in FIG. Similarly, there is a problem due to the frictional resistance of the pulley 014, the rotary shaft 019, etc., and the wear amount of the sample 015 varies. Therefore, the purpose of the present invention, in the Lambourn abrasion tester, to eliminate the dead load by minimizing the frictional resistance under load, to improve the accuracy of the load even in the low load region, wear test without variation. To make it possible.

[0005]

The object is to detect the load by the load applying device in a load applying device for an abrasion tester which presses a sample against a grinding wheel by applying a load to the sample. Load cell, a sample mounting portion provided on one end of the load cell via a connecting shaft, and an air cylinder connected to the other of the load cell and having a piston rod for applying a load. Can be achieved by

[0006]

According to the present invention, the air cylinder for load application controls the moving speed of the sample until the sample comes into contact with the outer peripheral surface of the polishing wheel at the time of load application, and after the sample comes into contact with the polishing wheel. Also, the sample is pressed by the air cylinder, and a weight for load application, a counter balance weight, a pulley, an oil damper, etc. are not provided. In this way, since the dead load is eliminated and the frictional resistance is reduced, it is possible to perform a wear test without variation by lowering the air pressure to the air cylinder, especially in the low load region.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, one embodiment according to the present invention will be described with reference to the drawings. FIG. 1 is a side view showing the present embodiment. In FIG. 1, reference numeral 1 indicates the wear tester as a whole, and reference numeral 3 indicates a sample mounting portion 4 at the tip of the load applying device 2.
It is a sample for wear test made of a vulcanized rubber attached to, and has a ring shape with an outer diameter of about 50 mm and a width of 5 mm. Reference numeral 5 is a disc-shaped grinding wheel for abrading the sample 3, which is rotated by a motor A (not shown) in the direction of the arrow. The cylindrical sample mounting portion 4 is rotated in the arrow direction by a motor B (not shown). The rotary shaft 6 of the sample mounting portion 4 and the rotary shaft 7 of the polishing wheel 5 are arranged in parallel. Code 8
Is a tube for dropping sand 9 on the rotating contact portion between the sample 3 and the polishing wheel 5 in order to prevent the sample 3 from sticking during the test.
Is connected to the lower part of the hopper (not shown) that stores the upper sand 9.

The load applying device 2 has a connecting shaft 10 along an axis L orthogonal to the rotating shaft 6 of the sample mounting portion 4, one end of the connecting shaft 10 is connected to the sample mounting portion 4, and the other end is a load. It is connected to one of the load cells 11 for detection. The other side of the load cell 11 is connected to the tip of a piston rod 13 of an air cylinder 12 for load application. And
The axis of the air cylinder 12 coincides with the axis L, and the air cylinder 12 is detachably mounted integrally on the fixed frame 16. The speed controllers 19 and 20 are provided on the pipes 17 and 18 of the air cylinder 12, respectively. By adjusting these speed controllers 19 and 20, the moving speed of the piston rod 13 can be adjusted. There is.

Further, a pressure adjusting valve 21 as shown in the block diagram of FIG. 2 is installed at the air supply source on the upstream side of the pipe 18, and the air pressure can be changed by adjusting the pressure adjusting valve 21. By this, the force of the piston rod 13 moving in and out can be adjusted, and the load applied to the sample 3 can be adjusted. Further, the pressure control valve 21 can be adjusted by the servo motor 22, and the load cell 1
By comparing the load detected by 1 and the value set by the load setting device 23, it is controlled so that a predetermined constant load is always applied during the test. Reference numeral 14 is a slide bearing that supports the connecting shaft 10 so as not to rotate about the axis L and to move horizontally, and is detachably mounted integrally on the fixed frame 16. Reference numeral 15 is a test tank which encloses the grinding wheel 5, the sample mounting portion 4 and the like for the prevention of scattering of the sand 9 and the safety of the test, and a part thereof is shown. And sample 3,
Sample mounting part 4, rotating shaft 6, connecting shaft 10, load cell 1
1, the air cylinder 12, the piston rod 13, the slide bearing 14, the pipes 17 and 18, the speed controllers 19 and 20, the pressure control valve 21, the servo motor 22, the load setter 23 and the like constitute the load applying device 2 as a whole. There is.

Next, the operation of applying a load to the sample 3 and pressing the sample 3 against the polishing wheel 5 will be described. now,
It is assumed that the sample 3 and the polishing wheel 5 are separated from each other. First,
Sample 3 and polishing wheel 5 are motor B and motor A, respectively.
To start rotation. Next, after adjusting the pressure control valve 21 on the upstream side of the pipe 18 to set the load on the sample 3 to a predetermined value, the speed controller 19 on the pipe 17 side is adjusted so that when the piston rod 13 projects. Make the speed extremely slow. Next, the air cylinder 12
When the piston rod 13 is actuated, the piston rod 13 projects at an extremely slow speed, and the outer peripheral surface of the sample 3 and the outer peripheral surface of the polishing wheel 5 come into contact with each other. The moving speed of the piston rod 13 at this time is
When the sample 3 which is a rotating elastic vulcanized rubber comes into contact with the outer peripheral surface of the rotating polishing wheel 5, the moving speed is sufficiently slow so that the sample 3 does not jump up due to the reaction force.

Even after the sample 3 is in contact with the grinding wheel 5, the pipe 18 of the air cylinder 12 is supplied with the air accurately controlled to a constant pressure from the pressure control valve 21, and the sample 3 is continuously subjected to a predetermined load. Be loaded into. At this time, the air chamber of the air cylinder 12 functions as an oil damper of the prior art, and the sample 3 bounces or vibrates while the sample 3 and the polishing wheel 5 rotate while making contact with each other. Nor. Then, after wear for a predetermined time, the air cylinder 12 is operated to retract the piston rod 13, and then the sample 3 is removed to measure the wear amount. In this way, the sample 3 is continuously loaded with a precisely controlled predetermined load, and while the sample 3 and the grinding wheel 5 are rotating while being in contact with each other,
The sample 3 does not bounce or vibrate, the variation in the amount of wear is small, and the test accuracy and the reproducibility of the test are extremely excellent.

[0012]

As described above, according to the present invention,
When a load is applied to the sample and the sample is pressed against the polishing wheel, the moving speed at which the load is applied to the sample can be set to a predetermined speed or less at which the sample does not jump up. Furthermore, according to the present invention, since the sample 3 is continuously applied with a predetermined load which is accurately controlled even while the sample 3 and the polishing wheel 5 are rotating while being in contact with each other, a particularly low load is applied. Even in the range, the accuracy of the load applied to the sample was improved, the variation in the wear amount of the sample was small, and the test accuracy and the reproducibility of the test were improved.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment according to the present invention.

FIG. 2 is a block diagram of a main part according to the present invention.

FIG. 3 is a schematic overall view of a load applying device for a conventional Lambourn abrasion tester.

FIG. 4 is a schematic overall view of a load applying device for an abrasion tester disclosed in Japanese Utility Model Laid-Open No. 61-184952.

[Explanation of symbols]

01: Weight 02: Sample 03: Polishing wheel 04, 04 ': Counterbalance weight 05: Air cylinder 06: Piston rod 07: Oil damper 08, 08': Pulley 09: Slide bearing 010: Load cell 011: Rotating shaft 014 : Pulley 015: Sample 016: Grinding wheel 017: Air cylinder 018: Weight 019: Rotating shaft 1: Abrasion tester 2: Load test device 3: Sample 4: Sample mounting part 5: Grinding wheel 6: Rotating shaft 7 : Rotating shaft 8: Pipe 9: Sand 10: Connection shaft 11: Load cell 12: Air cylinder 13: Piston rod 14: Slide bearing 15: Test tank 16: Fixed frame 17, 18: Piping 19, 20: Speed controller 21: Pressure Control valve 22: Servo motor 23: Load setting device L: Axis

Claims (1)

[Claims] 1. A load applying device for an abrasion tester, wherein a sample is pressed against a polishing wheel by applying a load to the sample, a load cell for detecting the load, and a connecting shaft at one end of the load cell. A load applying device for an abrasion tester, comprising: a sample mounting portion provided through the air conditioner; and an air cylinder connected to the other side of the load cell and having a piston rod for applying a load.