JPH0474660B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a bearing running test machine that measures the friction coefficient of a bearing, the change in clearance between the bearing and the shaft, the amount of wear, etc.

The bearing running test machine of the present invention is particularly suitable for running tests of synthetic resin bearings, oil-impregnated alloy bearings, and other bearings used in boundary lubrication regions or in non-lubricated conditions.

(Prior Art) The coefficient of friction, clearance, and amount of wear of a bearing have important meaning as guidelines for bearing performance and in designing the optimal bearing for the load speed.

Among these, a typical configuration of a testing machine for measuring the coefficient of friction is introduced in Nikkan Kogyo Shimbunsha, Vol. 29, No. 10, p. 95 of Industrial Materials. To give an overview of this conventional bearing running test machine, a torque detection lever is attached to a bearing holder that fixes the bearing to be measured at the center, and the lever is brought into contact with a load cell.

Furthermore, no special testing machine has been proposed for measuring the amount of wear, and at present, measurements are carried out individually using pin gauges or the like.

(Problems to be Solved by the Invention) Conventional bearing running testing machines measure only the friction coefficient as described above, and cannot measure changes in wear amount, clearance, etc. On the other hand, when measuring the clearance of a bearing using a conventional pin gauge, after running it on a bearing running test machine for a certain period of time,
This was done with the bearing removed, but the actual clearance when the shaft is fitted to the bearing and running is significantly different from the values measured by the pin gauge. The reason for this is that when the shaft is fitted into the bearing and rotates, the bearing becomes extremely hot and the inner diameter of the bearing changes compared to when it is at room temperature. However, since the measurements are performed at room temperature, which is different from the temperature during use, there is a large difference between the actual values and the measured values.

In particular, when the bearing to be measured is made of resin, the above-mentioned difference exceeds a negligible range because of its large coefficient of thermal expansion. Furthermore, since there is a strong correlation between clearance and friction coefficient, when measuring the performance of a bearing, it is desirable to measure both simultaneously while the bearing is running.

However, measurements under the above conditions were not possible with conventional bearing running test machines.

Therefore, the present invention focuses on the drawbacks of the prior art, and
The purpose of this paper is to propose a bearing running test machine that can simultaneously and continuously measure the clearance and friction coefficient of a bearing while the bearing is running.

(Means for Solving the Problems) Therefore, the features of the present invention for achieving the above-mentioned object include a ring that is rotatable in the center and has a torque arm integrally provided therein, and the ring A load is applied in the normal direction of the rod, and a rod is provided on a bearing holder that is fixed to the main body so as to be movable in the same direction, and a load meter is in contact with the torque arm. A displacement gauge is connected to the link to measure the amount of movement of the test object, a bearing is attached to the link as an object to be measured, and a rotating shaft is inserted into the bearing.

(Function) Among the above-mentioned components of the present invention, the ring includes:
Although rotational torque is applied by the rotating shaft, the ring does not rotate because the torque arm, which is integrally fixed to the ring, is in contact with the load cell.

Therefore, the rotating shaft and the ring slide between the rotating shaft and the bearing that is the object to be measured attached to the ring, and the coefficient of friction between the two is displayed on the load meter via the torque arm. Further, a load is applied to the ring in one direction via a bearing holder, and it is attached to the main body so that it can be freely rotated in the direction of rotation and movable in the direction of the load. Therefore, when the clearance between the shaft and the bearing changes due to bearing wear or the like, the ring moves integrally with the bearing holder in the direction of the load, thereby moving the rod fixed to the bearing holder. Since a displacement gauge is connected to the rod, changes in the clearance between the bearing and the shaft are directly displayed on the displacement gauge.

(Example) Specific examples of the present invention will be further described below.

FIG. 1 is a front view of a bearing running test machine in a specific embodiment of the present invention, FIG. 2 is a left side view of the bearing running test machine in a specific embodiment of the present invention, and FIG. FIG. 2 is an enlarged partial cross-sectional view of the ring and its surroundings in FIG. 1;

In FIG. 1, reference numeral 1 denotes a bearing running test machine in a specific embodiment of the present invention. The bearing running test machine 1 consists of a rotating main shaft 2 and a measuring section 3. The rotating main shaft 2 is connected to an electric motor and a transmission device (not shown), and can be rotated by power. A tapered hole 4 is provided at the tip of the rotating main shaft 2 concentrically with the main shaft 2, and a rotating shaft 6 having a journal 5 provided at the tip is inserted into the tapered hole 4.

On the other hand, the measuring section 3 includes a bearing holder 7 and a load cell 8.
and a dial gauge 9. In the bearing holder 7, a ball bearing 10 having a much smaller coefficient of friction than the bearing to be measured is integrally fixed inside a frame-shaped body having a pentagonal outer shape, and a torque arm 11 is further fixed integrally to the inner ring of the ball bearing 10. The ring 13 has a hole in the center and a ring 13 into which a bearing 12, which is the object to be measured, is fitted.

Here, the torque arm 11 described above is the ring 1
A trapezoidal extension part 15 whose tip is bent parallel to the axis of the bearing 12 is provided in one direction of the circular mounting part 14 having a hole in the center, which generally coincides with the shape of the circular mounting part 14.
Furthermore, a square bar 1 having a contact point 16 is attached to the bent portion.
7 was installed.

Further, a temperature sensor 18 such as a thermocouple or a resistance temperature detector is embedded in the ring 13. A rod 20 having a weight 21 in the middle is attached to the pentagonal apex corner of the bearing holder 7. The bearing holder 7 described above is inserted with both sides fitting into guides formed by two groove members 19 provided in the main body frame 30 of the bearing running test machine 1, and is moved in a direction perpendicular to the main body. are combined in a state where they can be

Further, the journal 5 of the rotating shaft 2 is inserted into the bearing 12 within the link 13.

Further, the rod 20 is suspended vertically downward through a groove in a stopper 23 provided in the main body. The bottom surface of the rod 20 is in contact with a detection rod of a dial gauge 9 fixed to the main body 30, and the vertical movement of the bearing holder 7 is displayed as a numerical value on the dial gauge 9 via the rod 20. There is. Further, the load cell 8 is disposed at the upper part of the rotating shaft 2 in the rotational direction, and at a position where the load detection section 22 is within the rotational radius of the contact point 16 of the torque arm 11.

The operation of each part of this embodiment will be explained below.

The rotating shaft 2 of this embodiment is rotated to a predetermined rotational speed by an electric motor and a transmission device (not shown), and the journal 5 is rotated within the bearing 12 via the tapered shaft 6. At this time, since the ring 13 is rotatably fixed to the main body by the ball bearing 10, rotational force is transmitted to the ring 13 and it tries to rotate.

However, the torque arm 11 is fixed to the ring 13, and the contact point 16 of the torque arm 11 rotates together with the ring 13, and the load cell 8
Since the ring 13 comes into contact with the detecting portion 22 of the ring 13, the ring 13 itself does not rotate, but both slide between the journal 5 and the bearing 12 to be measured. Then, the ring 13 presses the detection section with torque due to the frictional force between the journal 5 and the bearing to be measured 12, and the torque is detected as a load by the load cell.

On the other hand, the bearing holder 7 is connected to the ring 13 via a ball bearing 10, and is movable only vertically with respect to the main body by a guide 19, and is subjected to a constant downward vertical load by a weight 21. is added, so that when the clearance between the bearing 12 to be measured and the journal 5 changes, the change is directly transmitted to the bearing holder 7, causing the bearing holder 7 to move up and down. As the bearing holder 7 moves up and down, the rod 20 also moves up and down, and the bottom surface of the rod 20 pushes the detection rod of the dial gauge 9 to directly display the change in clearance as a numerical value.

Furthermore, a temperature sensor 18 embedded within the ring 13 simultaneously displays the temperature at that time.

By preparing rotary shafts having journals corresponding to the inner diameters of a large number of bearings to be measured and by replacing only the rotary shafts, it is possible to use a single running test machine of the present invention for various inner diameters.

(Effects) The bearing running tester of the present invention has the effect of being able to simultaneously measure the friction coefficient and the change in bearing clearance under running conditions.

Therefore, in addition to measuring changes in bearing wear and determining the appropriate bearing clearance for the load, it is also possible to measure changes in oil film thickness over time when bearings are used with fluid lubrication. .

Further, by embedding a temperature sensor in the ring as in the embodiment, temperature changes can also be measured by adding the relationship between clearance and friction coefficient.

[Brief explanation of the drawing]

1 is a front view of a bearing running test machine in a specific embodiment of the present invention, FIG. 2 is a left side view of the bearing running test machine in a specific embodiment of the present invention, and FIG. 3 is a front view of a bearing running test machine in a specific embodiment of the present invention. FIG. 2 is an enlarged partial cross-sectional view of the ring and its surroundings in FIG. 1; 1... Bearing running test machine, 2... Main shaft, 3... Measuring section,
5... Journal, 6... Rotating shaft, 7... Bearing holder, 8... Load cell, 9... Dial gauge, 10
...Ball bearing, 11...Torque arm, 12
...Bearing, 13...Ring, 18...Temperature sensor, 2
0... Rod.

Claims (1)

[Claims] 1 A bearing that has a rotatable ring in the center and is integrally provided with a torque arm, is loaded with a load in the normal direction of the ring, and is fixed to the main body so that it can move in the same direction. A rod is provided on the holder, a load meter is brought into contact with the aforementioned torque arm, a displacement gauge is connected to the rod to measure the amount of rod movement, and a bearing as the object to be measured is attached to the ring. Furthermore, a bearing running test machine is characterized in that a rotating shaft is inserted into the bearing.