JP2534424B2 - Tire rim fitting strength measuring device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tire rim fitting strength measuring device capable of quantitatively, accurately and easily measuring the rim fitting strength of a rim-assembled tire.

[0002]

2. Description of the Related Art In recent years, with the development of highways, the speed of automobiles and motorcycles is increasing. With the speeding up of such vehicles, the frequency of sudden braking is increased during high-speed running, and when sudden braking is applied to the tires, the tires and the rims are misaligned, resulting in poor rim assembly accuracy and tires. Impairs the durability of.

Conventionally, in order to determine a rim deviation, a test tire is mounted on an actual vehicle, and at the time of a test road, 1
By repeatedly performing a sudden braking test in which sudden braking is applied during traveling at a high speed of 00 km / H or more, a tire and a rim cause a rim displacement in the circumferential direction, and the displacement length is measured.

[0004]

However, since the above judgment method is an evaluation by an actual vehicle test, it is affected by the condition of the vehicle, the condition of the road surface, the difference in braking performance, etc. It was an inappropriate method for quantitative evaluation.

Further, since four tires are required for the actual vehicle test, the test cost increases, and there is a problem that the repeated braking and braking accelerates the driver. For this reason, the appearance of a device that can quantitatively grasp the rim fitting force of a tire and that can easily measure the rim fitting force has been expected.

The present invention is provided with a rotary shaft provided with a connection fitting to which a rim can be fixed, a drive means for rotating the rotary shaft, and a torque detection tool for detecting torque generated in the rotary shaft. Another object of the present invention is to provide a tire rim fitting strength measuring device capable of quantitatively measuring the rim fitting strength and easily operated.

[0007]

SUMMARY OF THE INVENTION According to the present invention, a fixing means for holding the outer peripheral surface of a tire assembled to a rim to fix the tire, and a rotatably rotatably supported on the tire axis. A rotating shaft having a connecting metal fitting capable of fixing the rotating shaft at one end, a driving means for rotating the rotating shaft at the other end side, and a torque detecting tool for detecting a torque generated on the rotating shaft by the driving means. It is a tire rim fitting strength measuring device.

[0008]

With the above structure, the torque detector can quantitatively grasp the torque acting on the rotating shaft immediately before the rim displacement occurs, and can accurately measure the rim fitting strength.

Further, since the tire can be measured even in a room without being mounted on an actual vehicle, the measurement is simplified and the measurement efficiency is improved.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In the figure, a tire rim fitting strength measuring device (hereinafter referred to as a measuring device) 1 is a tire 3 assembled on a rim 2.
Fixing means 4 for fixing the rotating shaft 5, a rotating shaft 5 extending on the tire axis L, a driving means 6 for rotating the rotating shaft 5, and a rotating shaft 5.
And a torque detector 7 for detecting the torque generated in the.

In the present embodiment, the fixing means 4 has an upper projecting piece 14A and a lower projecting piece 14B which project horizontally and in the same direction from the upper and lower parts of the uprights 13 standing on the base 12.
A pedestal 15 having an upper and lower overhanging pieces 14A, 1
4B is provided with pressing members 16, 16 each of which is composed of a pair of hydraulic cylinders whose rod ends face each other, and a pressing piece 17 having a pressing surface along the outer peripheral surface 3A of the tire 3 is arranged at each rod end. To be done.

The tire 3 is a pneumatic tire in this embodiment, and its bead portion 3B is fitted on the rim 2. Further, the rim 2 has a ring-shaped rim body 21 having bead seat portions on both sides in the axial direction in which the bead portions 3B and 3B are fitted,
The desk 22 has a flat disk shape in which a plurality of bolt holes capable of attaching the rim 2 to the axle of the vehicle are arranged radially around the tire axis L.

The two pressing tools 16 and 16 operate in the same operation and in synchronization, and the expansion of the pressing tools 16 causes the tire 3 to be fixed to the base 12 by the fixing means 4 while maintaining the position of the tire axis L thereof. Fixed. The fixing means 4 may be formed by radially arranging three or more pressing tools so that they can be pressed toward the tire axis L and simultaneously.

The rotating shaft 5 is axially supported by a plurality of bearings 25 mounted on a frame 24 provided on the base 12 and extends on the tire axis L. Further, in the present embodiment, the rotating shaft 5 includes a connecting portion 5A arranged on one end side facing the tire 3 and a driving portion 5B arranged on the other end side to which the driving means 6 is connected.
It is composed of a detecting section 5C interposed between these connecting section 5A and driving section 5B. Further, the connection portion 5A and the detection portion 5C, and the drive portion 5B and the detection portion 5C are fixed in series by a coupling 26 ...

At one end of the connecting portion 5A facing the tire 3, a connecting fitting 9 for connecting the rim 2 and the rotating shaft 5 is provided.
The connection fitting 9 is a disc body fixed to the rotation shaft 5 so as not to rotate by, for example, a key stopper, and has a screw protruding in accordance with the position of the bolt hole of the rim 2.
The rotating shaft 5 can be fixedly connected to the rim 2 on the tire axis L by inserting the bolt into the bolt hole and fixing the nut.

The drive means 6 is a prime mover 6 for generating torque.
A and a transmission 6B for transmitting the output torque of the prime mover 6A to the rotary shaft 5. Since the prime mover 6A can generate a large torque and is small, a torque motor,
A hydraulic motor or the like can be preferably used, and a reduction gear device can be attached to the output end thereof as required. In this embodiment, the prime mover 6A is attached to the mount 24.

The transmission 6B is a gear transmission in this embodiment, and a transmission mechanism using a chain, a belt or the like can be adopted in addition to the gear transmission. Further, the output shaft of the prime mover is directly connected to the rotary shaft 5. Axial coupling is also possible.

The torque detector 7 is a device for measuring the torque acting on the rotary shaft 5 transmitted from the driving means,
It is necessary to provide the torque detecting tool between a portion where torque is applied to the rotary shaft 5, that is, between the connecting fitting 9 and the engaging position where the driving means 6 is engaged.

In this embodiment, the torque detector 7 is provided in the detector 5C of the rotary shaft 5 and is additionally provided with a recorder 7A for recording the detected torque value with time. As the torque detecting tool 7, a twist angle detecting type torque sensor for measuring the twist angle of the rotating shaft 5, a strain gauge type torque sensor,
Various torque sensors such as a magnetostrictive torque sensor that detects torque by utilizing changes in magnetism can be adopted.

Then, the tire 3 to be tested is rim-assembled with the rim 2, and the tire assembled with the rim is fixed to the rotary shaft 5 via the connection fitting 9. Further, the outer peripheral surface 3A of the tire 3 is tightened by using the fixing means 4, and the tire 3 is firmly fixed so as not to move.

After that, the driving means 6 is operated to apply a rotating torque to the rotating shaft 5. As the torque of the rotating shaft 5 increases, the same torque acts on the rim-assembled tire 3 to deform the tire 3, but the bead portion 3B of the tire 3 and the rim seat portion of the rim 2 fit together. However, a torque greater than the maximum static friction force acts on the assembly of the tire 3 and the rim 2, so that a circumferential displacement occurs between the tire 3 and the rim 2.

Once a deviation occurs between the tire 3 and the rim 2, a dynamic friction state between them is lower than the static friction, and the deviation is continuously continued. FIG. 2 shows the relationship between the time H and the torque T when the torque acts. In the figure, point A shows the maximum static friction when the shift starts, and point B shows the state where the shift continues due to the subsequent dynamic friction.

The fitting strength between the tire 3 and the rim 2 can be quantitatively grasped by reading the torque detecting tool 7 at the time of the static friction at which the rim shift starts.

In the present invention, a linear actuator such as a hydraulic cylinder and a crank mechanism may be used as the driving means 6 and torque may be applied to the rotary shaft 5. The present invention has various aspects. It can be transformed.

Even when the tire is a pneumatic tire or a solid tire, the device of the present invention can be used.

[0026]

As described above, the tire rim fitting strength measuring device of the present invention has the above-mentioned configuration, so that the fitting strength can be quantitatively grasped as compared with the conventional actual vehicle test. The measurement work can be performed easily.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of the present invention.

FIG. 2 is a graph showing changes in acting torque over time.

[Explanation of symbols]

 2 rim 3 tire 3A outer peripheral surface 4 fixing means 5 rotating shaft 6 driving means 7 torque detecting tool 9 connecting fitting L tire axis

Claims (1)

(57) [Claims] 1. A fixing means for gripping an outer peripheral surface of a tire assembled to a rim to fix the tire, and a connecting metal fitting extending on the tire axis and rotatably supported and capable of fixing the rim. A rim fitting strength measurement of a tire, comprising: a rotation shaft, a drive means for rotating the rotation shaft on the other end side, and a torque detection tool for detecting a torque generated on the rotation shaft by the drive means. apparatus.