JPS6012704Y2 - Device to prevent unauthorized supply of screw parts in automatic screw tightening machines - Google Patents

Description

[Detailed description of the invention] The present invention is based on a screwdriver bit that is connected to a rotational drive source and rotates and reciprocates so as to tighten screw parts such as screws or bolts supplied from a parts supply device to a workpiece. a nose having a guide hole for guiding the screwdriver bit; a pair of jaws pivoted opposite to the tip of the nose, the tip of which is always urged to close so as to hold one screw component; The screwdriver bit is pivoted so as to be able to swing freely at the 7-piece so that it crosses the guide hole when feeding screw parts and is pushed out of the guide hole during tightening work, and is always biased by a spring so that the tip reaches the guide hole. In an automatic screw tightening machine consisting of a chuck unit consisting of a supplied supply pipe, the threaded parts are supplied with pressurized air when the tip of the supply pipe does not reach the guide hole in the nose and is lifted up. The present invention relates to an unauthorized supply prevention device that prevents illegal supply.

In general, when screw parts with a relatively short leg length relative to the head diameter are supplied from a parts supply device to the chuck unit of an automatic screw tightening machine, and the screw parts are automatically tightened to a workpiece, the leg length is relatively short relative to the head diameter. When tightening a relatively long threaded part, the nose used for the work, that is, the supply hole and guide hole are
If a cross-shaped screw type was used, the screw parts would fall over at this Y-shaped portion, making it impossible to tighten the screws onto the workpiece.

For this reason, at present, instead of a supply hole that intersects with the guide hole,
When supplying threaded parts, the supply pipe whose tip reaches the part holding part of the jaw is pivoted to the nose so that it can swing freely, and during tightening work, use a screwdriver bit to push the supply pipe away against the spring and then remove the threaded parts. Automatic screw tightening machines that tighten screws onto a workpiece are becoming popular.

However, in this method, if the tip of the supply pipe does not reach the nose guide hole for some reason, or if the supply pipe is pushed aside and the tightening work is being performed, when the next threaded part is supplied, This threaded part does not enter the jaws and instead flies out from the supply pipe, causing problems such as damage to the workpiece and injury to the operator, resulting in a lack of safety.

The present invention was devised for the purpose of solving such problems, and one embodiment will be described below based on the drawings.

1 and 2, 1 is a driver bit rotated by a rotational drive source (not shown), and this driver bit 1 is fixed to a driver body (not shown) containing the rotational drive source. The chuck unit A is reciprocably inserted into a guide hole 4a of a nose 4 of a chuck unit A fixed to an inner cylinder 3 which is loosely inserted into an outer cylinder 2.

A pair of left and right jaws 5, which are swingable in opposition to each other, are pivotally supported on the nose 4, and the jaws 5 are constantly biased so as to close their tips.

The jaws 5 are formed with component holding portions 5a that hold the screws 6 with the legs first, and the jaws 5 are each formed with a component holding portion 5a to prevent the screws 6 held in the component holding portions 5a from flowing backward. A check pawl 7 is built in, which is constantly biased so that the tip approaches the head of the screw 6.

Further, a supply pipe 8 having one end connected to a parts supply device (not shown) and the other end of a supply hose (not shown) connected to the nose 4 is swingable on a plane perpendicular to the swinging plane of the jaw 5. This supply pipe 8 is connected to the nose 4 with a screw 9.
It is constantly biased so that it reaches the inside of the guide hole a.

In addition, the nose 4 has a U-shaped fitting 1 as shown in Figure 2.
0 is fixed, and this fixture 10 has a jaw 5 at the tip.
The other end of the blocking plate 11 that reaches directly above the is attached.

The distal end of the blocking plate 11 is in a position to close the distal end of the supply pipe 8 as shown in FIG. 3 when the supply pipe 8 rotates in the A direction.

Next, the operation of this embodiment will be explained.

As shown in FIG. 1, when the supply pipe 8 has reached the guide hole 4a, when one screw 6 is supplied with pressurized air from the component supply device, the screw 6 passes through the supply pipe 8 and connects to the pair of screws 6. It is held in the component holding portion 5a of the jaw 5 with the legs first.

Thereafter, since the driver bit 1 reciprocates while rotating, the screw 6 is tightened to the workpiece 13 as shown in FIG.

At this time, the supply pipe 8 is pushed away from the guide hole 4a by the forward movement of the driver bit 1 against the spring 9, and rotates in the direction A.

When the tightening operation is completed, the driver bit 1 stops rotating and moves back, so the tip of the supply pipe 8 is rotated by the spring 9 again in the direction of the mouth and reaches the inside of the guide hole a, allowing the next screw to be screwed. 6 can be supplied.

On the other hand, as shown in FIG. 3, a supply signal is input for some reason during tightening work, that is, while the tip of the supply pipe 8 is being pushed away from the guide hole 4a, and the next screw 6 is tightened.
Even if the tip of the supply pipe 8 does not reach the guide hole 4a and is floating when the specified tightening work is completed and the screw 6 is supplied again in the regular work cycle, at this time The supplied screws 6 are blocked by the blocking plate 11 so that they do not fly out.

Further, FIGS. 4 to 6 show another embodiment of the present invention, in which a blocking portion 5b is integrally provided on one of the pair of jaws 5 in place of the blocking plate 11 of the previous embodiment. It was formed.

As shown in FIG. 5, this blocking portion 5b has a width sufficient to close off the tip of the supply pipe 8, so that if the supply pipe 8 does not reach the guide hole 4a due to the same reason as in the previous embodiment, Even if the screw 6 is supplied as shown in FIG.
The screw 6 is prevented from coming out from the supply pipe 8 by coming into contact with the supply pipe 8.

A stopper 12 for restricting rotation of the supply pipe 8 in the A direction is fixed to the upper part of the blocking portion 5b.

As is clear from the embodiments described above, the present invention provides a blocking plate that is attached to the fixture 10 fixed to the nose 4 perpendicular to the opposing swinging surface of the jaw 5 and in front of the swinging tip of the supply pipe 8. A blocking means such as a blocking portion 5b formed integrally with either the jaw 11 or the jaw 5 is disposed, and when the tip of the supply tube 8 does not reach the guide hole 4a of the nose 4, that is, the tip of the supply tube 8 is Since the tip of this supply pipe 8 is closed when it is in a floating state, if the threaded part is supplied with pressurized air while the supply pipe is pushed away from the guide hole, the threaded part will not fly out forward. There is no.

Therefore, there is no damage to the workpiece, no injury to the worker, and extremely significant effects such as significantly improved safety.

[Brief explanation of the drawing]

Fig. 1 is a sectional front view of main parts showing one embodiment of the present invention;
The figure is a left side view of FIG. 1, FIG. 3 is a cross-sectional front view of the main part similar to FIG. 1 showing operation, and FIG. Figure 5 is the left side view of Figure 4, and Figure 6 is the left side view of Figure 4.
This figure is a sectional front view of a main part similar to FIG. 4 showing the operation state. A is a chuck unit, 1 is a driver bit, 2 is an outer cylinder, 3 is an inner cylinder, 4 is a nose, 4a is a guide hole, 5 is a jaw, 5a is a component holding part, 5b is a blocking part, 6 is a screw, 7 is a A check claw, 8 a supply pipe, 9 a spring, 10 a fixture, 11 a blocking plate, 12 a stopper, and 13 a workpiece.

Claims (1)

[Claims for Utility Model Registration] 1. A rotating and reciprocating driver bit is disposed on the nose, and opposing jaws are attached to the nose that are biased to close the tip, while a supply pipe is routed to the nose. In an automatic screw tightening machine having a chuck unit that is movably attached and biased by a spring so that the tip of the supply tube reaches below the driver bit, the tip of the supply tube is closed to the retracted position of the supply tube. A device for preventing unauthorized supply of screw parts, characterized in that a device for preventing unauthorized supply of screw parts is provided. 2. The device for preventing unauthorized supply of screw parts according to claim 1, wherein the blocking means is a blocking plate that is attached to a fitting fixed to the nose and reaches the front end of the supply pipe. 3. The device for preventing unauthorized supply of screw parts according to claim 1, wherein the blocking means is a blocking portion integrally formed on either one of the pair of jaws.