JPH0213948Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a device for measuring rotational torque of wheels of automobiles, etc.

The hub that constitutes the wheel of an automobile is rotatably attached to the nut via a bearing. In order to adjust the clearance of the bearing interposed between the hub and the nut, a nut is screwed onto the tip of the nut. As this nut is gradually tightened, the clearance of the bearing becomes smaller and the preload increases. If the preload on the bearing is small and the clearance is large, the wheel will wobble and will not be able to rotate smoothly, and the bearing will be damaged by vibration. On the other hand, if the preload is too large, the bearing will generate heat, and this heat will anneal the bearing, eventually causing wear and tear on the bearing. Therefore, it is necessary to adjust the tightening of the nut so as to apply a preload to the bearing so that it always has an appropriate clearance.

Conventionally, after assembling an automobile wheel, the wheel was lifted off the ground and the rotational torque was measured to determine whether an appropriate preload was being applied.
To make this measurement, a device with engaging parts at both ends that engage with a pair of symmetrical hub nuts was attached to the wheel, and a torque measuring tool was attached to the central attachment part to measure rotational torque. However, the distance of the hub nut from the center of the wheel differs depending on the car model, so it is necessary to equip each car model with the above-mentioned measuring device, which poses the problem of an extremely large number of types of measuring devices. It was hot.

The present invention was devised in view of these problems, and involves fixing an engaging cylinder that can engage with a hub bolt of a wheel to one end of a pair of parallel rods. One engaging part is provided with a rack extending in the same direction as the rod, another engaging part is configured point-symmetrically with the engaging part, and a pinion connectable to a torque measuring tool is provided in the center. It has a rotatably installed mounting part, and the rods of the two engaging parts are slidably fitted into the mounting part, and both racks and the pinion are engaged with each other, so that the rotation of the pinion brings the two engaging parts close to each other. The pinion is characterized in that the rotation of the pinion is fixed by the engagement between the engagement tube and the hub bolt as they separate. Therefore, the rotational torque of wheels of various sizes can be accurately measured.

An embodiment of the present invention will be described below with reference to the drawings. 1 to 3 show a torque measuring device according to this embodiment, and this device is composed of a pair of engaging portions 1 and 2 at both ends and a mounting portion 3 in the center. The engaging parts 1 and 2 have bases 4 and 5, respectively, and cylindrical engaging tubes 6 and 7 are fixed to these bases 4 and 5, respectively. (See Figure 4). Furthermore, rectangular columnar rods 8, 9 and 10, 11 are fixed in parallel to the bases 4, 5, respectively. Further, racks 12 and 13 are integrally connected to the rods 8 and 10, respectively.

On the other hand, the base 14 of the central attachment part 3 is
Both ends thereof are bent to form a pair of guide portions 15 and 16 having a U-shaped cross section. These guide parts 15 and 16 are provided with the rack 1, respectively.
2 and 13 are inserted. Furthermore, guide part 1
Rectangular cylindrical guide tubes 17, 18 and 19, 20 are fixed to the outer surfaces of 5, 16, respectively.
The rods 8, 9 and 10, 11 are inserted into these guide tubes 17, 18 and 19, 20 (see FIG. 5). Further, a circular hole 21 is formed in the center of the base 14;
A main shaft 22 is rotatably fitted in the main shaft 22 . The upper end of this main shaft 22 is shaped like a square column, and a torque measuring tool is attached thereto. Also, a pinion 24 is connected to the lower end of this main shaft 22 via a key 23.
is fixed (see Figure 6). This pinion 24 meshes with the pair of racks 12 and 13.

Therefore, according to the torque measuring device having such a configuration, by rotating the pinion 24 via the main shaft 22, the mounting portions 4, 5 to which the racks 12, 13 meshing with the pinion 24 are fixed, respectively. will be pushed toward or away from each other. Therefore, the engaging parts 1, 2 having the rods 8, 9 and 10, 11, which are slidably guided in the guide tubes 17, 18 and 19, 20 of the mounting part 3, respectively, extend and contract with respect to each other. The distance between them can be changed freely. Therefore, the distance between the engaging tubes 6 and 7 of the engaging portions 1 and 2 can be changed arbitrarily, and thereby, regardless of the size of the wheel, the engaging tubes 6 and 7 can be attached to hub bolts of various wheels.
7 can be engaged. Further, when the engagement tubes 6, 7 and the hub bolt are engaged, the movement of the racks 12, 13 is restricted, and the rotation of the pinion 24 is also restricted. Therefore, the rotation of the wheel is accurately transmitted to the pinion 24 via the engaging portions 1 and 2. Therefore, there is no need to prepare torque measuring devices with different dimensions for each wheel.

Further, according to the torque measuring device of this embodiment, the racks 1 attached to the engaging portions 1 and 2, respectively.
2 and 13 are meshed with a common pinion 24,
Therefore, the rotation of the pinion 24 causes the two racks 12, 13 to move in synchronization with each other. For this reason, if it is set correctly at first, the pair of engaging parts 1 and 2 will extend and contract so that the main shaft 22 is always centered. Therefore, by attaching the torque measuring device to the main shaft 22 that always coincides with the axle, torque can be measured quickly and accurately.

Next, the operation of measuring torque using this torque measuring device will be explained with reference to FIG. The hub 25 of the front wheel of an automobile has a pair of bearings 26 and 27.
It is rotatably supported by the knuckle 28 via. Note that roller bearings are used as the bearings 26 and 27 so as to have load capacity for radial load and thrust load. In order to maintain the clearance between these bearings 26 and 27 at an appropriate value and to provide an appropriate preload, a male thread 29 is formed at the tip of the knuckle 28.
A nut 30 that is screwed into the hole is tightened. A hub bolt 31 is implanted on the outer peripheral side of the hub 25, and a brake drum 32 and a wheel 33 are attached by the hub bolt 31. And in order to fix this wheel 33,
A hub nut 34 is screwed onto the hub bolt 31.

When measuring the rotational torque of such a wheel, first, the main shaft 22 is rotated, and the pair of engaging parts 1,
By adjusting the length between the two, the engaging cylinders 6 and 7 are engaged with the nuts 34 of the pair of hub bolts 31 located symmetrically with respect to the axis of the nut 28. At this time, the main shaft 22 of the mounting part 3 always connects the pair of engaging parts 1 and 2.
Since it is located at the center of the knuckle 28, it coincides with the axis of the knuckle 28. Therefore, by attaching a torque measuring tool to this rectangular cylindrical main shaft 22 and rotating it, the rotational torque of this wheel can be measured. If the rotational torque is large as a result of this measurement, tighten the nut 3.
0 is too tightly tightened and more than necessary preload is applied to the bearings 26 and 27, so the nut 30
Just loosen it up a little. On the other hand, if the measured torque value is small, the nut 30 has not been tightened enough, so it is only necessary to tighten it a little further. In this way, the wheel torque is measured and the bearings 26, 2 are
Set the preload of 7 to an appropriate value, and set the bearings 26, 27
can have appropriate clearance.

As described above, the present invention can be used to measure the torque of wheels of various sizes because the pair of engaged parts of the wheel and the pair of engaging parts that respectively engage can be expanded and contracted. can be used. Therefore, there is no need to prepare a large number of measuring devices of various sizes. In addition, the expansion and contraction movements of the pair of engaging parts are performed in synchronization with each other, and the mounting part is configured to always be at the center of the pair of engaging parts, so torque can be applied quickly and accurately. can be measured.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view of a torque measuring device according to an embodiment of the present invention, FIG. 2 is a plan view thereof, FIG. 3 is a bottom view thereof, and FIG. Figure 5 is a cross-sectional view taken along the line ~ in Figure 2, Figure 6 is a cross-sectional view taken along the ~ line in Figure 2, and Figure 7 is a longitudinal cross-sectional view of a wheel whose torque is being measured by this measuring device. . In addition, in the symbols used in the drawings, 1, 2...engaging part, 3... mounting part, 6, 7... engaging tube, 12,
13...rack, 22...main shaft, 24...pinion.

Claims (1)

[Scope of utility model registration request] An engagement tube is fixed to one end of a pair of parallel rods that can be engaged with a hub bolt of a wheel, and one of the rods is provided with a rack extending in the same direction as the rods. , another engaging part configured point-symmetrically with the engaging part, and a mounting part rotatably provided with a pinion connectable to a torque measuring tool in the center, The rod is slidably fitted into the mounting part, and both racks and the pinion are engaged, and as the pinion rotates, the two engaging parts approach and separate, and the rotation of the pinion is fixed by the engagement between the engaging cylinder and the hub bolt. A wheel rotation torque measuring device characterized in that: