JPH028668Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field of the Invention The present invention relates to an apparatus for press-fitting a part such as a bushing into a member to be press-fitted.

BACKGROUND ART With the automation of assembly work, the press-fitting process has come to be automatically performed by a press-fitting device in the assembly line. In this press-fitting process, press-fitting failures occur due to variations in the inner diameter dimensions of the holes in the press-fitted parts or variations in the parts to be press-fitted, so this type of press-fitting equipment is equipped with means for detecting the press-fitting state. There is.

For example, the invention disclosed in JP-A No. 59-7531 uses numerical control technology to control the amount of movement of a press-fitting work shaft according to various parts, and measures the press-fitting load to determine whether the press-fit is good or not. I try to distinguish between them.
Although such a press-fit control device can perform various press-fit operations and press-fit management at the same time, the control device is complex, large-scale, and expensive, making it difficult to incorporate it into a relatively simple assembly processing line. be.

Purpose of the invention Therefore, the purpose of the invention is to use a cylinder as a general press-fitting means, without using advanced and complicated techniques such as numerical control technology or load measurement, and to achieve press-fitting by adjusting the position of the press-fitting rod. The goal is to be able to manage the state.

Summary of the invention Therefore, when a part such as a bush is press-fitted into a press-fitted member, the present invention verifies whether or not it has been press-fitted with a predetermined pressure by the moving position of the press-fitting rod.
Furthermore, by switching the pressure of the air cylinder for driving the press-fit rod between low pressure and high pressure, the quality of the press-fit condition is indirectly determined.

Configuration of the invention Hereinafter, the configuration of the invention will be specifically explained based on the drawings.

First, FIGS. 1 and 2 show a press-fitting device 1 for parts according to the present invention. This press-fitting device 1 includes a cylinder 3 for giving forward and backward movement to a press-fitting rod 2.
It is equipped with This cylinder 3 is of a double-rod type, and supports the press-fitting rod 2 at the tip of the cylinder rod 3a, and also supports a rat-toothed detection object 5, a block-shaped detection object 6, and a rear end thereof. It holds 7. These objects to be detected 5, 6, and 7 face the inside of a cylindrical holder 8. This holder 8 is attached to the tail head of the cylinder 3, and holds an intermediate stop switch 9, a rod position detection switch 10, and a backward limit confirmation switch 11 at positions corresponding to the detected objects 5, 6, and 7, respectively. are doing.

In front of the press-fitting rod 2, a press-fitted member 22 is positioned in its movement range by a jig 13 or the like, and is supported in a clamped state. Further, parts 15 such as a bush to be press-fitted into the hole 14 of the press-fitted member 12 are moved between the press-fitting rod 2 and the press-fitted member 1 by a supply arm 16 that can reciprocate.
It is supplied in a positioned state between 2 and 2. Note that this retraction of the supply arm 16 is performed by the stop release switch 2.
Detected by 5.

Next, FIG. 3 shows the control system. The high-pressure source 17 and low-pressure source 18 of the driving fluid are connected to the double-acting cylinder 3 via a switching valve 19 and a control valve 20 as switching means. The control valve 20 is for controlling the reciprocating movement and stopping of the cylinder 3, and is connected to the intermediate stop switch 9 and the stop release switch 25. Further, the stop release switch 25 is
It is connected to one input terminal of a comparator circuit 23 via a timer 21 as a time setting means and a pulse counter 22. This pulse counter 22 and the rod position detection switch 10 connected thereto constitute means for detecting the feed amount of the press-fitting rod 2. Further, the timer 21 is connected to the other input terminal of a comparison circuit 23 as comparison means via a position storage circuit 24. A coincidence output terminal and a mismatch output terminal of this comparison circuit 23 are connected to the switching valve 19 and the control valve 20, respectively.

Functions of the Device Next, a series of functions of the above-mentioned parts press-fitting device 1 will be explained.

The supply arm 16 reciprocates between a part 15 receiving position and a supply position, and sends out one part 15 while accurately positioning it to the supply position. On the other hand, first, the switching valve 19
is switched to the low pressure source 18, so that the cylinder 3 advances the press-fitting rod 2 from the retracted position under low pressure. At the beginning of this forward movement, the intermediate stop switch 9 detects the corresponding detected object 6 and sends a stop signal to the control valve 20, so the control valve 20 temporarily stops the press-fit rod 2 midway. . At this time, the tip of the press-fitting rod 2 fits loosely into the interior of the component 15 at the supply position and is held in a skewered manner.

At this point, the supply arm 16 retreats and escapes from the supply device, and the stop release switch 25 detects the retreat and sends a re-drive signal to the control valve 20, so the cylinder 3 continues to drive the press-fitting rod 2 at low pressure. advance. At the same time, the timer 21 operates, and after the low pressure feeding time has elapsed, the pulse counter 2
2 and the position storage circuit 24.
Therefore, the comparison circuit 23 calculates the amount of movement of the press-fitting rod 2,
That is, the number of pulses in the pulse counter 22 is compared with a first stored number preset in the position storage circuit 24.

When the two numbers do not match, in other words, when the press-fitting rod 2 enters further beyond the abutment position of the part 15 against the press-fitted member 12 (the opening edge of the hole 14), that is, the preparation position, and is at the press-fit completion position, it is a light press-fit. , or the supply of the component 15 is defective, that is, the press-fit is defective in any case, so the comparison circuit 23 is connected to the control valve 20
to drive the press-fitting rod 2 in the backward direction.

If both values match, the component 15 is in the predetermined ready position, and the comparator circuit 23 indicates that the switching valve 19
is switched to the high pressure source 17, that is, a predetermined pressure necessary for press-fitting the part 15. From this switching point, the cylinder 3 advances the press-fitting rod 2 with high pressure,
The tip part 15 is press-fitted under a predetermined pressure,
Press fit into hole 14. Since the timer 21 issues an output command again when a predetermined high voltage feeding time has elapsed from the time of high voltage switching, the comparison circuit 23 compares the output of the pulse counter 22 with the second stored number of the position storage circuit 24. By comparison, confirm the press-fitting position of the press-fitting rod 2.

When both numbers match, that is, press-fit rod 2
If it is at the press-fitting completion position, it corresponds to the normal press-fitting operation being completed, so the comparator circuit 23
operates the cylinder 3 by the control valve 20,
Retract the press-fitting rod 2. In this way, the press-fitting operation is repeated one after another.

When the two values do not match, that is, when the press-fit rod 2 is not in the predetermined position, it is considered that the press-fit is defective, and necessary measures are taken at that point.

Incidentally, when the press-fitting rod 2 is retracted, necessary portions are returned to the initial state by, for example, the retraction confirmation switch 11.

Variants of the invention The presence or absence of the component 15 at the supply position can also be detected by optical means on the supply side or in the middle of the press-in rod 2. The parts 15 may be supplied by a parts feeder or the like, and the parts 15 can be held by constructing a collection chuck at the tip of the press-fitting rod 2 and holding it in a skewered manner by opening and closing the chuck. You can also do this. Further, the means for detecting the amount of movement of the press-fitting rod 2 is not limited to the rod position detection switch 10 and the pulse counter 22, but may also be composed of an encoder, and the comparison means, that is, the comparison circuit 23, is configured to It may be provided separately. Furthermore, the part 15 may of course be other mechanical parts in addition to the bush.

Effect of invention The present invention provides the following unique effects.

Depending on the position of the press-fitting rod over time, it is possible to determine whether the press-fit condition is good or bad and even the cause thereof, thereby allowing correct press-fit management.

Even if the press-fitting position changes, by changing the setting value of the position memory circuit to be compared, press-fitting can be performed for different press-fitting parts and press-fitting depths, so changing the press-fitting rod and its stroke can be done easily. No special operations are required to change the information, making maintenance and management easier.

Furthermore, since press-fit management as described above can be determined in relation to the position of the press-fit rod and the time required for its movement, conventional numerical control devices and press-fit load measuring instruments are not required, resulting in a simple configuration. Press-fit management can be performed automatically.

[Brief explanation of the drawing]

Figure 1 is a side view of the parts press-fitting device of the present invention;
The figure is an enlarged sectional view of the movement amount detection portion, and FIG. 3 is a block diagram of the control system. 1... Parts press-fitting device, 2... Press-fitting rod, 3
... Cylinder, 4 ... Machine base, 5, 6, 7 ... Detected object, 8 ... Holder, 9 ... Intermediate stop switch, 10 ... Rod position detection switch, 11 ...
Retraction limit confirmation switch, 12...Press-fitted member, 13
... Jig, 14... Hole, 15... Parts, 16...
Supply arm, 17... high pressure source, 18... low pressure source,
19...Switching valve, 20...Control valve, 21
...Timer, 22...Pulse counter, 23...
... Comparison circuit, 24 ... Position memory circuit, 25 ... Stop release switch.

Claims (1)

[Scope of utility model registration request] A press-fit rod that supports parts such as bushes at its tip, a cylinder that feeds the press-fit rod at low pressure, a switching means that switches the driving fluid pressure of the cylinder to high pressure after the low-pressure feed time, and settings for the low-pressure feed time and high-pressure feed time. a detection means for detecting the feed amount of the press-fitting rod; a comparison means for comparing the amount of movement of the press-fitting rod during the low-pressure feeding time with a set value; and setting the amount of movement of the press-fitting rod during the high-pressure feeding time. A press-fitting device for parts, characterized in that the part is press-fitted into a member to be press-fitted located in a moving range of the press-fitting rod, and includes a comparison means for comparing the values.