JPH0226663Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> This invention relates to a press-fitting device for a perforated bush for press-fitting a perforated bush into a plastic product.

<Conventional technology> Conventionally, in order to embed a perforated bush into a plastic product (hereinafter referred to as the product), a boss for inserts is provided on the product, and the bush is inserted into the boss during molding. , insert molding is commonly used.

Another method is to mold the product by providing a boss with a press-fit hole, and after molding, press-fit a bush with a slightly larger diameter than the press-fit hole into the press-fit hole to integrally connect the products. ing. An example of such a press-in method is the method described in Japanese Patent Application Laid-Open No. 55-30937.

The jig disclosed for the above-mentioned press-fitting method consists of a pedestal that holds the product and a mandrel that reciprocates relative to the pedestal, and a tapered guide with a conical tip is attached to the lower end of this mandrel. It is provided so that it can be screwed on and removed. The inner cylinder, which corresponds to a bush, is fitted onto the mandrel and held by a tapered guide, so that the inner cylinder is press-fitted into the product. At this time, the tapered guide performs a guiding function when the inner cylinder enters the press-fitted product.

<Problem to be solved by the invention> However, in the case of the above-mentioned insert molding, if one forgets to insert the bushing during molding, the boss for the insert is filled with plastic, resulting in a product defect that is difficult to repair. It was hot.

In addition, when inserting bushes with different dimensions, for example, if the bushes are short due to the insert boss section, the same problem as mentioned above will occur, and if the bushes are too long, the bushes will get caught between the molds and the large mold The clamping force sometimes caused damage to the mold.
In order to solve problems such as mold damage, a huge amount of time and expense was required, and there were problems such as being forced to meet product delivery deadlines.

Furthermore, when using a press-fitting jig for the latter press-fitting method, it is necessary to take time to screw in and remove the tapered guide one by one during press-fitting. Furthermore, the centering of the bush and the product depends on the accuracy of mounting the pedestal on one side of the pressurizing means such as a press, and the accuracy of mounting the mandrel on the other side of the pressurizing means, resulting in inaccurate centering. It was made of hard plastic material and was unsuitable for use in products. In addition, the accuracy of the press-fitting depth of the bush depends on the stroke of the pressurizing means.
There was a problem that the press-fitting depth position of the bushing was inaccurate.

This idea was made to solve the above problems, and it prevents product defects and mold damage caused by forgetting to insert a bushing or inserting a bushing of a different size, and also prevents the press-fitting position of the bushing from being damaged. It is an object of the present invention to provide a press-fitting device for a perforated bush that can press-fit in an accurately defined manner.

<Means for solving the problem> This invention was made to achieve the above object, and includes a press-fit hollow shaft having a guide hole and capable of moving in the axial direction to press a perforated bush; A fixing fitting that supports a perforated bush and a press-fitting hole of a plastic product and is provided opposite to the press-fitting hollow shaft, the fixing fitting comprising:
It has a cylindrical main body, and is disposed in the center of the main body so as to share its axis, and is capable of fitting into a press-fit hole in a plastic product and a guide shaft into which the perforated bush can be externally fitted. an extruded hollow guide shaft with a tapered tip that has a tapered portion and is fitted onto the guide shaft and is movable in the axial direction; a stopper that defines a position on the rear end side of movement of the extruded hollow guide shaft with a tapered tip; This press-fitting device for a perforated bush is characterized by comprising a spring that biases an extruded hollow guide shaft with a tapered tip toward its tip.

<Function> This device is constructed as described above, and the tapered part of the extruded hollow guide shaft with a tapered tip fits into the press-fit hole of the plastic product for centering and guides. The shaft centers the perforated bushing, aligns the axes of the press-fit hole of the plastic product and the perforated bushing, and supports both.

The press-fit hollow shaft moves forward and presses the perforated bush into the press-fit hole.

As the perforated bush is press-fitted, the extruded hollow guide shaft with a tapered tip moves backward, and the plastic product moves in the backward direction and comes into contact with the tip of the main body of the fixing fitting, thereby defining the axial position. will be held.

By further pressing the press-fitting hollow shaft, the extruded hollow guide shaft with a tapered tip is further retreated and its rear end side contacts the stopper, and the press-fitting depth position of the perforated bushing is defined and the press-fitting is completed.

When the press-fitting hollow shaft retreats after the press-fitting is completed, the extruded hollow guide shaft with a tapered tip returns to its original position by the biasing force of the spring, and the plastic product into which the perforated bushing is press-fitted is separated by the fixing metal fitting.

<Example> Hereinafter, an example of this invention will be described based on the drawings.

FIG. 1 is a partially cutaway side view showing the structure of the perforated bush press-fitting device of this invention.

This press-fit device for a perforated bush includes a press-fit hollow shaft 6, a guide shaft 3, an extruded hollow guide shaft 2 with a tapered tip (hereinafter referred to as the extruded hollow guide shaft 2),
Fixing bracket 1 with stopper 5 and spring 4
It is composed of.

The press-fit hollow shaft 6 has a fixing fitting 1 on its axis.
A guide hole 6a into which the guide shaft 3 can be inserted is bored. The press-fit hollow shaft 6 is attached to a movable base 10 connected to a pressurizing means (not shown) such as an air cylinder, and is configured to be able to reciprocate in the axial direction.

The fixture 1 has a cylindrical main body 1a,
A guide shaft 3 is disposed at the center of the main body portion 1a, sharing the same axis, and an extruded hollow guide shaft 2 that is movable in the axial direction is fitted onto the guide shaft 3. Furthermore, within the main body portion 1a, a stopper 5 for defining the rear end position of the extruded hollow guide shaft 2;
A spring 4 that urges the extruded hollow guide shaft 2 toward its tip (rightward in FIG. 1) is installed coaxially therewithin.

The guide shaft 3 has an outer diameter that allows the perforated bush 7 to be externally fitted therein, and its distal end is formed into a conical shape and protrudes beyond the distal end of the main body portion 1a and the extruded hollow guide shaft 2 in the forward position. It is arranged as follows.

The extruded hollow guide shaft 2 is made of plastic product 8
It is formed into a cylindrical body with a diameter larger than the inner diameter of the press-fit hole 8a, and has a conical taper part 2a with a predetermined slope at the tip, and a flange-like flange part 2b is formed at the rear end. . The flange portion 2b is formed so as to come into contact with the step-in portion 1b of the fixture 1 to define the movement position of the extruded hollow guide shaft 2 on the forward side.

The extruded hollow guide shaft 2 is always urged by a spring 4 to move toward the tip, and the flange portion 2b is in contact with the stepped portion 1b, and the tapered portion 2a is configured to protrude from the tip of the main body portion 1a. ing. Also, when the extruded hollow guide shaft 2 is pressed to the left in FIG.
The rear end side b contacts the stopper 5 to define its moving end, and the tip surface of the extruded hollow guide shaft 2 and the tip surface of the main body portion 1a are configured to be flush with each other.

The fixture 1 configured in this way is attached to the fixing base 9 so as to face the press-fit hollow shaft 6 and to share the same axis.

The plastic product 8 is molded from a predetermined plastic material, and a press-fit hole 8 having a predetermined inner diameter and length is formed in the boss portion (not shown).
A is provided. Also, the perforated button 7 is
Its outer diameter is slightly larger than the press-fit hole 8a, and it is formed to have a predetermined inner diameter and length.

Next, the operation of the perforated bush press-fitting device will be explained.

First, the press-fit hole 8a of the plastic product 8 is fitted from the distal end side of the fixing metal fitting 1, and the press-fit hole 8a is fitted into the tapered portion 2a of the extruded hollow guide shaft 2.
At this time, the opening on one side of the press-fit hole 8a is centered by coming into contact with a substantially middle portion of the conical portion of the tapered portion 2a. Next, the perforated bush 7 is fitted onto the guide shaft 3 that protrudes through the press-fit hole 8a, and the press-fit hole 8a and the perforated bush 7 are positioned on the same axis.

Subsequently, when the movable base 10 is moved forward, the press-fit hollow shaft 6 moves in the direction of the fixing fitting 1, and the guide hole 6
As the guide shaft 3 enters the inside a, the end 6b of the press-fit hollow shaft 6 comes into contact with one end of the perforated bush 7 (see FIG. 2).

As a result, the press-fit hole 8a of the plastic product 8
and the perforated bush 7 are supported by the fixing fitting 1 and the press-fit hollow shaft 6 while having their axes aligned with each other.

When the press-fitting hollow shaft 6 moves further forward, the perforated bush 7 is pressed and enters the press-fitting hole 8a, and press-fitting starts.

Then, when the other end side of the perforated bush 7 that has entered the press-fit hole 8a comes into contact with the tip end surface of the extruded hollow guide shaft 2, the spring 4 is compressed by the above-mentioned pressing force, and the extruded hollow guide shaft 2 is moved to the second Move back to the left in the figure. At this time, the plastic product 8 also moves together with the extruded hollow guide shaft 2, and one side of the plastic product 8 comes into contact with the distal end surface of the main body portion 1a, thereby defining the position of the plastic product 8 in the axial direction.

When the press-fit hollow shaft 6 moves further forward, the extruded hollow guide shaft 2 further retreats, and finally the flange portion 2b
The rear end side contacts the stopper 5 (see Fig. 3).
As a result, the press-fitting depth position of the perforated bush 7 is defined, and for example, the other end side of the perforated bush 7 and one side of the plastic product 8 become flush, and the press-fitting is completed.

When the press-fitting is completed, the movable base 10 is moved backward and the press-fit hollow shaft 6 is moved to the right in the figure. At this time, the extruded hollow guide shaft 2 returns to its original position due to the biasing force of the spring 4, and the plastic product 8 into which the perforated bush 7 has been press-fitted is pulled away from the fixture 1 for easy removal ( Fourth
(see figure).

Then, the movable base 10 is further moved backward, the press-fit hollow shaft 6 is moved to a position where there is no problem in taking out the plastic product 8, and the plastic product 8 is taken out.

<Effects of the invention> The press-fitting device for a perforated bush according to this invention has the above-mentioned configuration, and the extruded hollow guide shaft with a tapered tip of the fixing fitting fits into the press-fitting hole of the plastic product and supports it. In addition, since the guide shaft penetrates and supports the perforated bush, the axes of the press-fit hole and the perforated bush can be accurately aligned. In addition, the main body of the fixing fitting defines the axial position of the plastic product, and the stopper defines the movement position of the extruded hollow guide shaft with a tapered tip on the rear end side, so the press-fit depth of the perforated bushing is It is possible to precisely define the position and press fit.

Therefore, accurate centering and press-fit depth positioning can be achieved simply by inserting the press-fit hole and perforated bush of the plastic product into the extruded hollow guide shaft with a tapered tip and the guide shaft of the fixture, respectively.
Press-fitting work can be performed accurately and quickly.

Furthermore, due to the action of the extruded hollow guide shaft with a tapered tip returning to its original position after press-fitting, the plastic product after press-fitting the bush is pushed out to a position where it can be easily taken out.
Work efficiency can be promoted.

Furthermore, it is possible to avoid product defects caused by forgetting to insert a bushing with a hole or inserting a bushing shorter than specified, and damage to the mold due to a bushing longer than the specification, and to avoid using bushings with holes in plastic products. Can be combined integrally.

As described above, according to the press-fitting device for perforated bushes of the present invention, it is possible to press-fit perforated bushes accurately and quickly with a little practice, improving press-fitting accuracy and reducing product defects. It is possible to increase economic effects by preventing occurrences and reducing the consumption of time and expenses.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway side view of a press-fitting device for a perforated bush according to an embodiment of this invention, Fig. 2 is a side sectional view showing the state immediately before press-fitting a perforated bush by this device, and Fig. 3 is the same. FIG. 4 is a side sectional view showing the press-fitting completed state, and FIG. 4 is a side sectional view showing the product before being taken out. 1...Fixing bracket, 2...Extruded hollow guide shaft with tapered tip, 3...Guide shaft, 4...Spring, 5...Stopper, 6...Press-fit hollow shaft, 7...
...Perforated bush, 8...Plastic product, 9
... Fixed booth, 10 ... Movable base.

Claims (1)

[Claims for Utility Model Registration] A press-fit hollow shaft having a guide hole and capable of moving in the axial direction to press a perforated bushing; a fixing metal fitting provided opposite to the shaft, the fixing metal fitting having a cylindrical main body, disposed in the center of the main body so as to share the axis thereof, and having the hole. a guide shaft into which a bushing can be externally fitted; an extruded hollow guide shaft with a tapered tip having a tapered portion which can fit into a press-fit hole of a plastic product and which is fitted externally into the guide shaft and movable in the axial direction; and the tip. A hole drill characterized by comprising: a stopper that defines a position on the rear end side of movement of the tapered extruded hollow guide shaft; and a spring that biases the extruded hollow guide shaft with a tapered tip toward its distal end. Press-fitting device for kibbutsuyu.