JP3063456B2 - Hub assembly 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 hub assembling apparatus capable of automatically performing press-fitting of a hub, smoothing-out of a bearing, and measurement of the rotational resistance of a bearing when a preload is applied in one process. is there.

[0002]

2. Description of the Related Art A unit bearing having opposed angular bearings provided in a housing for accommodating a vehicle axle is generally mounted on the unit bearing so as to prevent play in the axial direction. It is used in a state where a predetermined preload is added in the axial direction by an axle penetrating the hub and a nut for tightening the axle through a hub that supports the wheel of the tire (for example, Nissan Motor Co., Ltd. in September 1991). U13-1 "NISSAN Bluebird U13"
Type car ", see page C-106).

For this reason, when a hub is assembled to the above-mentioned unit bearing, as shown in FIG. 4, conventionally, as shown in FIG. The hub 3 is disposed above the inner race so that the cylindrical portion of the hub 3 is aligned with the inner race.
By pressing down the hub 3, the cylindrical portion of the hub 3 is pressed into the inner race until the enlarged diameter portion of the hub 3 comes into contact with the outer end surface of the inner race body. An operator presses the housing 2 while pressing the hub 3 with a thrust force (for example, 5t) corresponding to a preload to the outer end surface of the inner race of the unit race whose inner end surface is supported by the fixed base 1 of the unit bearing. By turning the bearing several times in both directions by hand, the bearings are turned in, and then
With the above-mentioned thrust force applied, the operator pulls the spring balance 5 applied to an appropriate part of the housing 2 in a tangential direction as indicated by an arrow to rotate the housing 2, and during the rotation, the spring balance 5 indicates The load is read, and the load value is multiplied by the distance between the axis of the housing 2 and the above-mentioned portion to measure the rotational resistance torque value at the time of preload, thereby assuring the assembly quality of the bearing portion.

[0004]

However, such a conventional method requires a large number of man-hours and a large variation in the measured rotational resistance because the smoothing rotation and the rotational resistance measurement are performed manually. There was a problem that it was easy.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a device which advantageously solves the above-mentioned problems, and a hub mounting device of the present invention comprises a unit bearing provided in a housing. A fixing member that receives the inner end surface of the inner race of the vehicle body, and is moved in a direction approaching the fixed member by being urged by the forward urging means, and pressing the hub against the inner race received by the fixing member. A ram for press-fitting a hub, and in a state where the ram presses the hub with a predetermined thrust force equivalent to a predetermined preload and holds the hub against an inner race received by the fixing member,
A rotation driving means for rotating a hanging member which engages with a part of the housing around the fixing member to rotate the housing with respect to the hub; and a rotation driving means provided in the rotation driving means, wherein the ram fixes the hub to a predetermined position. And a torque detecting means for detecting a driving torque while the housing is being rotated with respect to the hub while being pressed and held by a predetermined thrust force equivalent to a preload.

[0006]

In such an apparatus, the ram is first attached by the forward urging means while the fixing member receives, that is, supports, the inner end surface of the inner race of the inner race of the unit bearing provided in the housing. By being urged to move in the direction of approach to the fixing member and pressing the hub against the inner race received by the fixing member, the tubular portion of the hub is pressed into the inner race, and then the ram is moved to the hub. Is pressed by a predetermined thrust force equivalent to a predetermined preload and fixedly held against the inner race received by the fixing member, and the rotation driving means rotates the engaging member engaging with a part of the housing around the fixing member. Then, the housing is rotated with respect to the hub, so that the bearing is rotated in the preload added state. By rotating the ring relative to the hub, the rotation of the bearing for the measurement of the rotational resistance torque value at the predetermined preload applicator. Then, during the rotation of the bearing, the torque detecting means provided in the rotary driving means detects the driving torque to measure the rotational resistance torque value of the unit bearing.

Therefore, according to the apparatus of the present invention, the press-fitting of the hub, the smoothing rotation of the bearing, and the measurement of the rotational resistance of the bearing when the preload is added can be automatically performed in one step. The man-hour required for the measurement can be reduced, and the measurement of the rotation resistance can be stabilized because the measurement of the rotation resistance is not manually performed. In addition, according to the apparatus of the present invention, the rotation driving means can be used both during the smoothing rotation of the bearing and during the rotation of the bearing for measuring the rotational resistance torque value in the state where the accurate preload is applied by the pressing force of the ram. Since the drive torque can be detected and the rotational resistance torque value of the unit bearing can be measured from the drive torque, the rotational resistance torque value of the unit bearing in a preload added state can be measured with high accuracy, and The trouble of the running-in state can be easily found, and the cause investigation when the rotational resistance is excessive can be easily performed.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a hub assembling apparatus according to the present invention, and FIG. FIG. 4 is an enlarged cross-sectional view showing a state at the time, and in FIGS. 1 and 2, parts similar to those shown in FIG. 4 are denoted by the same reference numerals.

That is, the hub assembling apparatus of this embodiment is
A fixing base 1 as a fixing member, which is erected on a base 9 fixedly attached to a normal hydraulic press apparatus 8 so as to be aligned below the ram 4 of the press apparatus 8. As shown in detail in FIG. 2, an end surface of the inner race 6a of the inner race 6a of the unit bearing 6 provided in the housing 2 (a lower end surface in the figure) is provided at the distal end of the fixed base 1.
And a centering edge 1b which is smaller than the inner race receiving portion 1a and slightly larger than the inner race receiving portion 1a but slightly thinner than the counterbore portion 2a of the housing 2. Is provided.

The hub assembling apparatus of this embodiment is provided with a ram 4 which is urged by a hydraulic cylinder (not shown) of the press device 8 as a forward urging means and which moves up and down with respect to the fixed base 1, and a bearing. A rotating member 11 rotatably supported on the fixed base 1 through the rotating member 10. The rotating member 11 has an L-shaped projecting arm 11a as a hooking member extending laterally and upward. The protruding arm 11
The leading end of a is divided into two branches, and can be engaged with the link mounting arm 2b of the housing 2 to pinch it. A pulley 12 is fixed to a lower portion of the rotating member 11. The ram 4 is guided to move up and down by the cooperation of a guide rod 13 having a lower end fixed to the ram 4 and a guide sleeve (not shown) of the press device 8 so that the ram 4 does not rotate around its axis. .

Further, the hub assembling apparatus of this embodiment includes a rotation drive mechanism 14 as rotation drive means capable of rotating the rotation member 11 around the fixed base 1.
Is a motor 15 with a speed reducer fixed downward in the base 9 and a bracket fixed to the side of the base 9
An intermediate shaft 18 composed of a plurality of shafts coupled to each other via a coupling, rotatably supported by two bearings 17 via two bearings 17 and extending vertically, and the motor 15
A pulley 19 fixed to the tip of the output shaft of the first shaft, and pulleys 20, 21 fixed to the upper and lower ends of the intermediate shaft 18, respectively.
And belts 22 and 23 for drivingly coupling between the pulleys 12 and 20 and between the pulleys 19 and 21, respectively. The pulleys 12 and 20 have the same diameter.
18 and 21 have the same diameter.

In addition, the hub assembling apparatus of this embodiment is fixed to the bracket 16 and detects the torsional torque between the upper part and the lower part of the intermediate shaft 18 at the center of the intermediate shaft 18. A normal torque detector 24 as torque detection means,
A proximity sensor 25 capable of measuring the number of rotations of the rotating member 11 by detecting passage through a hole 20a formed in the lower surface of the pulley 20, the press device 8, the motor 15, a torque detector 24 and a proximity sensor 25 and a conventional programmable logic controller (PLC) 26 for controlling the operation of the device.

In the apparatus of this embodiment, as shown in FIG. 1, first, an operator places the housing 2 such that the link mounting arm 2b is engaged with the distal end of the projecting arm 11a of the rotating member 11. And, the inner peripheral surface of the counterbore 2a and the centering edge 1b are placed on the fixed base 1 so that they do not come into contact with each other, so that the inner race receiving portion 1a of the fixed base 1 is The inner race 6a of the provided unit bearing 6 receives the inner end surface (the lower end surface in the figure) of the inner race 6a, and then the operator places the hub 3 and the tip of the cylindrical portion 3a is the outer end surface of the inner race 6a (the lower end surface). It is placed on the inner race 6a so as to ride on the edge of the center hole at the upper end surface in the figure). Note that a dust seal (see FIG. 2) usually provided between the counterbore 2a and the unit bearing 6 assists the centering of the inner race 6a with respect to the inner race receiving portion 1a of the fixed base 1.

Next, here, the PLC 26 firstly
The hydraulic cylinder of the press device 8 is advanced to urge the ram 4 downward, whereby the ram 4 is lowered and should receive the nut of the hub 3 for fixing the axle to the hub 3, upward in the figure. By pressing the hub 3 against the inner race 6a received by the fixed base 1, the cylindrical portion 3a of the hub 3 is inserted into the inner race 6a, and the enlarged diameter portion 3b of the hub 3 Until it comes into contact with the outer end face of the inner race 6a.

Next, the PLC 26 adjusts the height of the hydraulic pressure applied to the hydraulic cylinder of the press device 8 in the advance direction, so that the ram 4 applies the hub 3 to the inner race 6a received by the fixed base 1 in a preload equivalent manner. The motor 15 is actuated so that its output shaft rotates, for example, to the left when viewed from above, while holding the thrust force by pressing with a predetermined thrust force on the fixed base 1 and holding the thrust force. Let me turn the intermediate shaft 18
By rotating the rotating member 11 and thus the protruding arm 11a around the fixed base 1 counterclockwise from above, the housing 2 is rotated counterclockwise with respect to the hub 3 in the same manner as the output shaft. If it is determined that the housing 2 has been rotated a predetermined number of times (for example, 5 times) based on the signal from 25, the housing 2 is rotated a predetermined number of times (for example, 5 times) in the same manner in the opposite right direction. The bearing 6 is turned on.

Then, during the smoothing rotation, P
The LC 26 causes the torque detector 24 to detect the torsional torque applied to the intermediate shaft 18 and, based on the detected torsional torque, rotate the rotating member 11 without engaging the housing 2 in advance.
The torsional torque (rotational resistance torque of the rotation drive mechanism 14 including the rotational resistances of the bearings 10 and 17) applied to the intermediate shaft 18 detected by rotating the shaft is subtracted, and the rotational resistance of the unit bearing 6 during the normalizing rotation is reduced. Find the torque value.

After that, the PLC 26 keeps the ram 4 to keep the thrust force corresponding to the preload, which presses the hub 3 against the inner race 6a, and operates the motor 15 to move the housing 2 to any one of the hubs 3. One rotation in the direction (for example, rightward), and the rotation under the thrust force is performed, the torque detector 24 is also connected to the intermediate shaft 18.
Is detected, and the rotational resistance torque of the rotary drive mechanism 14 itself is subtracted from the detected torsional torque. The rotation resistance torque value of No. 6 is obtained.

FIG. 3 exemplifies a change state of the rotation resistance torque value of the unit bearing 6 at the time of the above-mentioned normal rotation and at the time of adding the preload, and a criterion thereof. And the characteristic curve R shows the torque change at the time of right rotation.
AR indicates the leveling rotation area, area MR indicates the preload measurement area, and range OK indicates the acceptable torque range.

That is, in this example, the smoothing rotation of five rotations on the left and right and the rotation of one rotation on addition of the preload are sequentially performed. At the time of the smoothing rotation, first, the rotation is performed to the left. Measure the rotation resistance torque value after the first one rotation elapses until the end of five rotations, then reverse and rotate to the right, and after the first one rotation elapses until the end of the five rotations During this period, the rotational resistance torque value is measured. The measured values are used as characteristic curves L, R
If the acceptable torque range is within the above range, the unit bearing 6 is judged to be in a good condition and the next preloading rotation is performed. On the other hand, if the measured values are out of the acceptable torque range, OK It is determined that there is a problem caused by, for example, insufficient grease, foreign matter in the bearing, scratches, etc. in the break-in state. I do.

In addition, when the preload is applied after the above-described normalizing rotation, the motor is rotated rightward once and the rotation resistance torque value is measured during the rotation, and the measured value is used as the characteristic torque R as shown in FIG. If it is within the range OK, it is determined that the rotational resistance of the unit bearing 6 when the preload is added is acceptable. On the other hand, if the measured value is outside the acceptable torque range OK, the rotational resistance of the unit bearing 6 is not acceptable. Judge as a pass. At the start point of the measurement at the time of adding the preload, the measured value may be within the acceptable torque range OK as shown at point A in the illustrated example, but is outside the acceptable torque range OK as shown at point B in the illustrated example. In such a case, it is conceivable that the leveling rotation is insufficient, so that the PLC 26 may perform the leveling rotation again.

After that, here, the PLC 26 is a motor
The operation of 15 is stopped to stop the rotation of the housing 2, and the hydraulic cylinder of the press device 8 is retracted to raise the ram 4 to open the housing 2.
An operator carries out the housing 2 on which the hub 3 has been assembled from the fixed base 1.

Therefore, according to the apparatus of this embodiment, the press-fitting of the hub 3, the leveling rotation of the unit bearing 6, and the measurement of the rotational resistance of the unit bearing 6 when the preload is added are automatically performed in one step. Therefore, the man-hour required for the smoothing rotation and the rotation resistance measurement can be reduced, and the measurement of the rotation resistance can be stabilized because the measurement of the rotation resistance is not manually performed.

In addition, according to the apparatus of this embodiment, the rotation resistance of the unit bearing 6 during the running-in operation is also measured, so that a trouble in the running-in state can be easily found. Can be easily investigated when the value is too large.

Although the present invention has been described with reference to the illustrated examples, the present invention is not limited to the above examples.
Slidably fits into the center hole of the cylindrical portion 3a of the fixed base 1 to form an inner race with respect to the inner race receiving portion 1a.
A centering shaft member for ensuring centering of 6a may be provided in the inner race receiving portion 1a, and if necessary, for example, the centering shaft member or a means for positioning the housing 2 only during press-fitting. To ensure the centering of the inner race 6a with respect to the inner race receiving portion 1a,
The fixing table 1 and the ram 4 may be provided sideways to rotate the housing 2 about a horizontal axis, and the rotation driving means may be driven without using a belt using a bevel gear or the like. Can also.

[0025]

As described above, according to the hub assembling apparatus of the present invention, the press-fitting of the hub, the smoothing rotation of the bearing, and the measurement of the rotational resistance of the bearing when the preload is added can be automatically performed in one step. Therefore, the man-hours required for the smoothing rotation and the measurement of the rotational resistance can be reduced, and the measurement of the rotational resistance can be stabilized because the measurement of the rotational resistance is not manually performed. Moreover, according to the device of the present invention,
The drive torque of the rotation drive means is detected and driven during both the smoothing of the bearing and the rotation of the bearing for measuring the rotational resistance torque value in the state where the accurate preload is applied by the ram pressing force. Since the rotational resistance torque value of the unit bearing can be measured from the torque, the rotational resistance torque value of the unit bearing with the preload added can be measured with high accuracy, and the trouble of the leveling state can be easily found. Therefore, it is possible to easily investigate the cause when the rotation resistance is excessive.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of a hub assembling device of the present invention.

FIG. 2 is an enlarged cross-sectional view showing a state of a main part of the apparatus of the embodiment at the time of completion of hub press-fitting, at the time of smoothing rotation thereafter, and at the time of measurement of rotational resistance.

FIG. 3 is a characteristic diagram showing an example of a rotational resistance measurement result by the apparatus of the embodiment.

FIG. 4 is an explanatory view showing a conventional hub assembling method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fixed base 2 Housing 3 Hub 3a Tubular part 4 Ram 6 Unit bearing 6a Inner race 8 Press device 11 Rotating member 11a Protruding arm 14 Rotary drive mechanism 15 Motor 24 Torque detector 25 Proximity sensor 26 PLC

Claims (1)

(57) [Claims] 1. A fixing member (1) for receiving an inner race end face of an inner race (6a) of a unit bearing (6) provided in a housing (2), and is urged by forward urging means (8). A ram (4) which moves in a direction approaching the fixing member and presses the hub (3) against the inner race received by the fixing member to press- fit the hub; in receiving condition in which the relative inner race ram is fixed and held by pressing the hub with a predetermined thrust force of a predetermined preload equivalent, the fixing member about the engaging member (11) which engages a portion of the housing Rotating drive means (14) for rotating the housing with respect to the hub by rotating the housing; and a ram provided in the rotary drive means, wherein the ram connects the hub to the hub.
Press and fix with a predetermined thrust force equivalent to a predetermined preload
And a torque detecting means (24) for detecting a driving torque while rotating the housing with respect to the hub while holding the hub.