JPH06155193A - Bearing bush pressing-in device - Google Patents

Abstract

PURPOSE:To perform simultaneous pressing of bearing bushes into a pair of respective bearing holes by means of properly set press-in thrust without deformation of a partition wall by a method wherein the bearing bushes are pressed in the bearing holes of the thin partition wall of a die-cast molded casing work, having bearing holes on the same axis and at least one pair of thin partition walls, through relative approach movement of a pair of press-in heads. CONSTITUTION:When a work 10 is positioned by a pair of grasping claws 40a and 40b brought into light contact holding of the inner surfaces of partition walls 45a and 45b, positioned facing each other, bearing holes 10a and 10b formed on the same axis in the partition walls 45a and 45b and through-holes 43a and 43b formed in a pair of the claws are formed in a manner to be positioned on the same axis. Bearing bushes 12a and 12b locked to the two ends of a guide pin 42 inserted in the bearing holes and the through-holes for support are simultaneously pressed in the bearing holes 10a and 10b by means of press-in thrust of press-in heads 34a and 34b generated by ball screws 32a and 32b rotationally driven in a way to set to torque to a proper value with the aid of a single electric motor 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION A bearing with a press-fitting thrust that is preferably set by relative approach movement of a pair of press-fitting heads to a die-cast molded work having at least a pair of thin-walled partitions having bearing holes coaxially on the horizontal axis. The present invention relates to a press-fitting device that press-fits a bush into the two bearing holes at the same time.

[0002]

2. Description of the Related Art Generally, a press-fitting device for press-fitting a bearing bush or the like has a structure in which the bearing bush is press-fitted with a considerably large press-fitting thrust. When press-fitting the bearing bush into the coaxial bearing hole of the thin partition, a large load is applied to the press-fitted housing, and if the housing is insufficiently supported, this press-fitting thrust may cause the housing to move. Since there is a possibility of deformation, a mounting jig that supports the housing sufficiently and reduces the influence of the press-fitting thrust is manufactured and press-fitted. Moreover, since the device is configured so that the press-fitting direction is approximately the movement from the vertical axis (vertical) direction, it cannot be press-fitted as it is, depending on the shape of the housing. It is general that the method of doing is taken.

[0003]

As described above, when a bearing bush or the like is press-fitted into the partition wall of the housing formed thin by the conventional press-fitting device, if the press-fitting thrust is large, the housing is deformed or cracked. Etc. are likely to occur, and for this reason, the mounting jig is manufactured by sufficiently supporting the housing to reduce the influence of the press-fitting thrust force, but the manufacturing cost of this mounting jig is considerably high. In addition, since the setup change is performed several times, it takes a long time to attach and remove the case using the attachment jig of the housing, and a considerable amount of time is required for the setup change.

Some housings have a structure in which they are press-fitted in the horizontal axis direction, and a mounting jig for the housing is manufactured so that they can be press-fitted in the vertical axis direction. It has to be press-fitted, and this requires a considerable amount of time for changing the setup. However, when mass production is carried out by flow work, the press-fitting device installed on this production line is basically equipped with a press-fitting mounting jig, reducing setup time such as removal, and improving the product yield rate. This is an issue, and along with this issue,
Considering the material and wall thickness, there has been a demand for the development of a press-fitting device that can maintain high accuracy in a short time without deformation due to press-fitting.

Therefore, an object of the present invention is to provide an excessive press-fitting thrust force to a die-cast molded casing work having at least a pair of thin partition walls having coaxial bearing holes, by a relative approach movement of a pair of press-fitting heads. It is an object of the present invention to provide a bearing bush press-fitting device capable of simultaneously press-fitting a bearing bush into the bearing hole with a press-fitting thrust force that is suitably set so as not to apply.

[0006]

In order to achieve the above object, a bearing bush press-fitting device according to the present invention positions and grips a work by a mounting jig, and coaxially mounts on the thin partition walls facing each other. In the bearing bush press-fitting device that press-fits the bearing bush into the pair of bearing holes provided above,
The mounting jig is provided with a pair of claws that can be opened and closed in the horizontal direction, and a through hole is formed in the claws, and the inner walls of the thin partition walls facing each other are brought into contact with each other by the outward opening operation of the claws. At this time, the through hole is configured so as to be positioned coaxially with the bearing hole of the work, and a guide pin formed in the through hole of the claw and having substantially the same diameter as the through hole is inserted together with the bearing hole at the same time. It is characterized in that a pair of bearing bushes inserted and locked at both ends are press-fitted into the bearing holes by an appropriate thrust force of a pair of press-fitting heads arranged opposite to both end portions of the guide pin.

In this case, the press-fitting head is guided by and supported by a pair of screw shafts coaxially arranged so as to be opposed to each other so as to be relatively movable back and forth, and is transmitted by a single drive source via a transmission mechanism. A pair of bearing bushes locked to both ends of the guide pin are guided to the guide pin by moving the two ends of the guide pin closer to each other in the screw axial direction by an appropriate axial thrust generated by a torque that is set. At the same time, it is preferable that the bearing holes are simultaneously press-fitted.

[0008]

According to the bearing bush press-fitting apparatus of the present invention, the relative approach movement of the pair of press-fitting heads to the die-cast molded casing work having at least a pair of thin partition walls coaxially having the bearing holes causes excessive movement. The bearing bush is configured to be press-fitted into the bearing hole at the same time with a press-fitting thrust that is set appropriately so that press-fitting thrust is not applied. The yield rate is improved, and the press-fitting work can be completed in a short time without changing the setup.

[0009]

Next, one embodiment of a bearing bush press-fitting device according to the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a schematic configuration diagram of a press-fitting apparatus of the present invention. Reference numeral 10 is a die-cast work, and this work 10 has a U-shaped cross-section and is horizontal to thin partition walls at both left and right ends. Bearing bush 12 on the same axis
Has bearing holes 10a and 10b into which is pressed.

The structure of the press-fitting device will now be described. The timing pulley 16 mounted on the output shaft of the electric motor 14 as a driving device is driven by a timing pulley 20 and a timing belt 15a on the driven side via an idle pulley 18a. Connected by. On the other hand, the idle pulley 18b is mounted on the same shaft as the idle pulley 18a and is connected to the driven side timing pulley 22 via the timing belt 15b. However, the timing pulleys 20 and 22 on the driven side respectively have bearings 33.
The shafts 25a and 25b are rotatably supported by a, 33b and 33c and 33d, and are attached to one ends of the shafts 25a and 25b that are coaxially opposed to each other. The shafts 25a and 25b are configured to rotate in opposite directions.

Further, timing pulleys 26a and 26b are attached to the other ends of the pair of shafts 25a and 25b, respectively, and an appropriate axial thrust is applied to a press-fitting head which will be described later in the middle of each of the shafts 25a and 25b. A torque limiter 24a whose upper limit of set torque can be adjusted to give
24b is provided.

In front of the shafts 25a and 25b, a pair of screw shafts 32a and 32b are coaxially arranged in parallel therewith.
(Hereinafter referred to as ball screws) are arranged so as to face each other, and these ball screws 32a and 32b respectively have bearings 30a and 30.
The timing belt 27 is rotatably supported by b.
Timing pulleys 28a, 28 locked to a, 27b
b is configured to transmit the forward and reverse rotations from the shafts 25a and 25b.

Press-fitting heads 34a and 34b, which are respectively disposed opposite to the ball screws 32a and 32b, are configured to move toward and away from each other on the same axis by the forward and reverse rotations of the ball screws 32a and 32b.

More specifically, the press-fitting heads 34a, 34
b is ball nuts 33a and 33b which are respectively screwed into the ball screws 32a and 32b, and the ball nut 3
3a and 33b are fixed to each other and integrally formed with the pair of abutment blocks 35a and 35b, which are supported by guide rails (not shown) so as to be coaxially movable forward and backward. A pair of press-fitting heads 34a, 34b are provided with a pair of facing claws 40a, 40b of a mounting jig (not shown) which can be opened and closed in a horizontal direction by an indexing operation of a work table between the facing surfaces of the contact blocks 35a, 35b. Partition wall 45a,
The work 10 that is pressed and held from above is positioned and arranged in a state where the inside of 45b is lightly abutted by the outward opening operation.

In this case, the pair of claws 40a, 40b are lightly abutted so as not to deform the inside of the partition wall of the work 10 thereby, and the through holes 43a, 43 bored in the claws are formed.
b is the bearing holes 10a, 1 of the partition walls 45a, 45b of the work 10
0b and the through hole 43.
The a and 43b are formed to have substantially the same diameter as the outer diameter of the guide pin 42 that locks bearing bushes 12a and 12b, which will be described later, at both ends, and these are formed in the bearing holes 10a and 10b of the partition walls 45a and 45b.
When the is pressed, the guide pin 42 is inserted and held. In addition, a through escape hole 36a is provided coaxially with the guide pin 42 between the facing surfaces of the contact blocks 35a and 35b.
36b is formed to avoid interference with the guide pin 42 when the bearing bush is press-fitted.

The operation of the bearing bush press-fitting device of the present invention thus constructed will be described in detail below with reference to FIG. The work 10 is positioned and fixed on an indexable work table (not shown) by lightly abutting the insides of the thin partition walls 45a, 45b formed on the work 10 by a pair of outwardly opening claws 40a, 40b of a mounting jig. . Then, when the pair of claws lightly abut the insides of the thin partition walls 45a, 45b of the work 10, the through holes 43a, 43b formed in the claws 40a, 40b become the bearing holes 10 of the partition walls 45a, 45b.
It can be located on the same axis as a and 10b.

In the previous step, both partition walls 4 of the work 10 are
A pair of bearing bushes 12a, 12b are positioned outside the bearing holes 5a, 45b coaxially with the bearing holes 10a, 10b and the through holes 43a, 43b by a transport device (not shown). The bearing bushes 12a and 12b are inserted into the bearing pin 12a and 12b from both ends of the guide pin 42 by being inserted from the horizontal axial direction (transverse direction) by a carrier device.

In this state, the workbench is indexed to work 10
Is positioned at a predetermined position immediately before the press-fitting device, the electric motor 14 is activated, and the pair of shafts 25a and 25b are reversely driven via the timing belts 15a and 15b. Belt 27
a, a screw shaft 32a coaxially arranged via 27b,
32b is transmitted.

Therefore, these ball screw shafts 32a, 32
The abutment blocks 35a, 35b of the pair of press-fitting heads 34a, 34b screwed to the b are guided by guide rails (not shown) so that they are coaxial with each other and the horizontal axis of the work 10 is directed toward the work 10 from both left and right sides. Approaching, bearing bush 12
bearing holes 10 of partition walls 45a and 45b by pressing a and 12b.
It is smoothly pressed into a and 10b.

At this time, the insides of the thin partition walls 45a and 45b are lightly contacted by the claws 40a and 40b whose outer opening amounts are adjusted.
It is possible to prevent the deformation of a and 34b due to the press-fitting thrust. Further, both ends of the guide pin 42 are connected to the press-fitting head 34.
The abutment blocks 35a, 3a, 3b as the a, 34b move toward each other.
5b into the escape holes 36a, 36b, and the guide pin 4
2 and the contact blocks 35a and 35b can be prevented from interfering with each other.

In this case, when the bearing bushes 12a, 12b are press-fitted into the bearing holes 10a, 10b, both contact blocks 35a, 35b contact the side surfaces of the work 10 partition walls 45a, 45b and both partition walls 45a, 45b. The thrusts of the contact blocks 35a and 35b act on the side surfaces, but at this time, the press-fitting thrust exceeds the initially set value of the torque limiters 24a and 24b, and the torque limiter 24 slips by itself due to the action of a load above this set pressure. As a result, the work 10 is prevented from being deformed or cracked because an excessive press-fitting thrust does not act on the partition walls 45a and 45b.

At the same time, since the torque limiter 24 slips, a bush press-fitting completion signal is output, the electric motor 14 starts reverse rotation, the press-fitting head 34 moves backward to a predetermined initial position and then stops, and the bearing bush 12a, 12b
The work 10 in which is pressed is transferred to the next step (station) by the indexing operation of the work table. Since the torque limiter 24 can variably adjust the setting of the maximum press-fitting thrust force, it is possible to select an appropriate set pressure depending on the press-fitting condition of the bearing bush.

In the present embodiment, the pair of ball screws 32a and 32b are arranged such that the same screws are coaxially opposed to each other and are rotated in the opposite direction so as to move toward and away from each other. However, ball screws having opposite lead angles (right and left threads) are coaxially arranged to face each other.
Needless to say, the same function can be obtained even if they are rotated in the same direction. Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and it goes without saying that various design changes can be made without departing from the spirit of the present invention.

[0024]

As described above, the bearing bush press-fitting device of the present invention is provided with a pair of pawls capable of opening and closing the mounting jig in the horizontal direction and forming through holes in the pawls, and at the same time, the work is The through hole is arranged so as to be coaxial with the bearing hole of the workpiece when the inner wall of the thin partition wall is brought into contact with the inner wall by the outward opening operation of the claw, and the through hole of the claw has substantially the same diameter. A pair of bearing bushes, which are inserted through the guide pins formed at the same time as the bearing holes and are locked at both ends of the guide pins at the same time, by the proper thrust of a pair of press-fitting heads arranged opposite to both ends of the guide pins. Since the work is not deformed or cracked after the bearing bush is pressed, the product yield rate is improved and the setup can be done in a short time without changing the setup. Since the press-fitting operation can be completed, and therefore the press-fitting device of the present invention can control the press-fitting thrust, the work can be press-fitted without applying an excessive load (friendly to the work). It has an excellent effect that it can be press-fitted and can contribute to the improvement of productivity.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a press-fitting device according to the present invention.

[Explanation of symbols]

 10 Work 10a, 10b Bearing hole 12 Bearing bush 14 Drive source (electric motor) 15a, 15b Timing belt 16 Timing pulley 18a, 18b Idle pulley 20, 22 Timing pulley 24a, 24b Torque limiter 25a, 25b Shaft 26a, 26b Timing pulley 27a , 27b Timing belts 28a, 28b Timing pulleys 32a, 32b Screw shafts (ball screws) 33a, 33b Ball nuts 34a, 34b Press-fitting heads 35a, 35b Abutment blocks 40a, 40b Claws 42 Guide pins 43a, 43b Through holes 45a, 45b Partition walls

Claims (2)

[Claims] 1. A bearing bush press-fitting device in which a work is positioned and gripped by a mounting jig, and a bearing bush is press-fitted into a pair of bearing holes coaxially formed in opposing thin-walled partitions formed in the work. Is provided with a pair of claws that can be opened and closed in the horizontal direction, and has a through hole formed in the claw, and the through hole is formed when the claws are brought into contact with the inner wall of the thin partition wall facing the work by the outward opening operation of the claw. Is positioned coaxially with the bearing hole of the workpiece, and the guide pin formed in the through hole of the pawl and having substantially the same diameter as that of the pawl is inserted together with the bearing hole, and at the same time, inserted into both ends of the guide pin. A pair of bearing bushes that are stopped are press-fitted into the bearing hole by an appropriate thrust of a pair of press-fitting heads that are arranged opposite to each other at both ends of the guide pin. Location. 2. The press-fitting head is screw-engaged with a pair of coaxially opposed screw shafts, is guided and supported so as to be relatively movable forward and backward, and is transmitted by a single drive source via a transmission mechanism. A pair of bearing bushes locked to both ends of the guide pin are guided by the guide pin by moving the guide pins closer to each other in the screw axis direction from the outside of both ends of the guide pin by an appropriate axial thrust generated by the torque set torque. The bearing bush press-fitting device according to claim 1, wherein the bearing bushing press-fitting device is configured to press-fit into the bearing holes at the same time.