JPS5916898B2 - Automatic assembly method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic assembly method used when assembling a large number of gears to a main plate like a clock movement, or when fitting a large number of small parts such as heat-welded rivets and washers. It is something.

The conventional automatic assembly method places automatic insertion machines at equal intervals along the conveyor line that conveys the main parts, stops the conveyor after each interval, and each insertion machine inserts the specified part into the specified location. It was something to do. This conventional method requires two-axis control for each insertion machine, which makes the device complicated.Also, since the conveyor device must be stopped every time, an expensive drive is required to prevent errors in the stopping position caused by mechanical "backlash." There were drawbacks such as the need for additional equipment. The present invention allows a conveyor to run continuously and drop small parts at the same time to perform insertion and assembly, thereby reducing costs by using a single-axis control of the dropping device that replaces the above-mentioned insertion machine, and increasing the speed and reliability of the device. The purpose is to measure ro. The present invention will be described in detail below using an example in which the present invention is applied to an assembly device for a movement of a quartz watch. FIG. 1 explains the main part of the method of the present invention, and shows the case where the main plate 1 of the movement is the main part and the gear 2, which is a small part, is fitted and attached to the main part. In figure a, the base plate 1 is conveyed horizontally to the right in the figure by a conveyor 3, and the gear 2 is held by a parts dropping device 4 and lowered to a predetermined position, where it stands still in the state shown in figure b. When the main plate 1 comes to the position shown in figure c, the component dropping device 4 is actuated by the signal from the control j0 device and the gear 2 starts to fall, and the main plate 1 is just below the dropping device 4 in figure d. At the point when the gear 2 passes through the base plate 1, the gear 2 reaches the base plate 1 and is loosely fitted onto the gear shaft 5 implanted in the base plate 1. During this time, the base plate 1 is conveyed at a uniform speed of i5 without stopping, and in Figure e, the dropping device 4 is raised to prepare for the next cycle. FIG. 2 shows an embodiment of the component dropping device 4, in which a cylindrical suction head 6 is moved up and down by a piston cylinder.
An elastic material T such as rubber is fixed to the lower edge of the
The interior is depressurized with a vacuum pump.

An ejector pin 8 driven by a solenoid is provided at the center of the head 6, and at the lower end of the ejector pin 8 there is an annular projecting wall 9 for ejecting the gear 2 in a horizontal state and a shaft of the gear 2 for positioning. A protruding shaft 11 is formed to be inserted into the hole 10 by 5'. Figure 3 shows the overall structure of the automatic assembly device, which is a parts dropping device that is mounted on a movable frame 12 that can move freely in a direction perpendicular to the direction of movement of the conveyor 3, and has a suction head 6 that can move up and down at the lower end. A plurality of child parts 4 are arranged in parallel along the conveyor 3, and each child part 2 is sucked and held one by one from each part supply device 13 on the side of the conveyor by each suction head 6, and transferred to the upper part of the conveyor 3. The part 2 is dropped onto a predetermined location on the parent part 1 which is being conveyed by a conveyor 3. Each component supply device 13 consists of a hopper portion 14 and a guide groove portion 15, and uses a vibrator to align small components, that is, gears 2, and transfer them to a stopper at the end of the guide groove portion 15 in a rush. A pallet 16 is fixed onto the belt conveyor 3 on which the main component, ie, the base plate 1 is fitted and placed. A suction head 1 for suctioning and transferring the main component 1 from the main component supply guide 17 is provided at the start end and the end end of a plurality of groups of suction heads 6 arranged in parallel.
8, and a suction head 20 for taking out the assembled finished product to the finished product carry-out guide 19. Reference numeral 21 denotes a photoelectric sensor for position detection, which detects the point in time when the pallet 16 passes and generates an operation timing signal for the component dropping device 4 by the control device.

22 is an operation panel.

Fig. 4 is an exploded view of the main part 1 and small part 2 to be assembled, and Fig. 5 shows the dimensional relationship between the unevenness of both parts 1 and 2. 5 outer diameter d
There is a larger "gap", but there is also a taper C between the two.
1 and C2 are provided to increase the gap margin L.

That is, it is sufficient that both parts meet while the shaft 5 in the figure moves from the position shown by the solid line to the position shown by the chain line, and the timing margin is equal to L divided by the conveyor speed. The figure shows the case of "clearance fit", but even in the case of "tight fit", a gap margin can be provided by the taper, and the part 2 fitted to the tapered part can be later pressed with a jig etc. All you need to do is take some measures.The conveyor speed should be 100~2
00 Dragon/Sec is appropriate, and increasing the ejecting speed by the ejecting pin 8 improves accuracy and increases the conveyor speed. In addition, by ejecting during suction and by forming the tip of the ejecting pin 8 into an annular shape,
Although the posture during the fall can be maintained almost horizontally, the posture can be controlled more accurately by guiding the shaft hole 10 with the protruding shaft 11 as shown in FIG. According to the method of the present invention, since the conveyor is run at a constant speed as described above, the equipment cost is low, and errors in the stop position of the conveyor or table do not become a problem, and the position detection sensor and clock device By synchronizing the timing with , the position control of the component dropping device only needs to be performed on the coordinate axes perpendicular to the conveyor, which simplifies the device significantly.Since the conveyor does not have to be stopped, the work time can also be shortened.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view explaining the principle of the method of the present invention.
-e shows the operating states in order, FIG. 2 is a cross-sectional view of a main part of one embodiment, FIG. 3 is an overall perspective view of the same, FIG. 4 is a perspective view of assembled parts used in the above, FIG. 5 is an enlarged sectional view of the main parts same as above. 1...Main parts or base plate, 2...Small parts or gears, 3...Conveyor, 4...
... Parts dropping device, 5 ... Gear shaft, 6 ...
...Adsorption head, 7...Elastic material, 8...
．． ．． ．． Ejection pin, 9... Annular projecting wall, 10.
...shaft hole, 11 ...protruding shaft.

Claims (1)

[Claims] 1. When assembling a main part and a small part that have irregularities that fit into each other, the main part is conveyed continuously in the horizontal direction, and the small part is dropped vertically downward from a resting position with an initial velocity applied to both parts. An automatic assembly method characterized by fitting each other at positions where the two meet.