JPH0641075B2 - Chuck unit of automatic screw tightener - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention is an automatic screw that is provided at the tip of an automatic screw tightening machine for screwing a screw supplied from a screw supply device to a work and that clamps the supplied screw. The chuck unit of a fastener machine.

<Prior Art> A conventional chuck unit of an automatic screw tightener will be described with reference to the drawings.

FIG. 5 is a partially cutaway side view of the automatic screw tightening machine for explaining the outline of the automatic screw tightening machine, FIG. 6 is an enlarged view of part a of FIG. 5, and FIG. 7 is B- of FIG. It is a B line sectional view.

The automatic screw tightener includes a drive source 10 such as a motor for rotating the driver bit 50, a first cylinder 20 for vertically moving only the suction pipe 60, and a second cylinder 30 for vertically moving the driver bit 50 and the suction pipe 60. , A chuck unit that holds the screw 90 supplied from a screw supply device (not shown)
40 and.

The chuck unit 40 is attached to the tip of the second base 70, and the second cylinder 30 is attached to the other end. A first base 80 is attached to the tip of an elongated U-shaped operating rod 31 that transmits the operation of the second cylinder 30 by screwing or the like. The drive source 10 and the first cylinder 20 are attached to the first base 80. In other words, the first base 80 is the second cylinder 30
It can move up and down.

The driver bit 50 is attached to the main shaft 11 of the drive source 10 and is also included in the suction pipe 60. This suction pipe 60 is connected to a suction device (not shown),
The first cylinder 20 can move up and down.
The tip of the suction pipe 60 is formed to be slightly thin.

The main body 41 is attached to the second base 70 by screws or the like, and is configured so that the driver bit 50 and the suction pipe 60 are inserted. The chuck unit 40 is formed in a generally V shape when viewed from the front. The chuck unit 40 includes a main body 41, a nose 42 that is provided to be inclined with respect to the main body 41, guides the screw 90 supplied from the screw supply device to the chuck unit 40, and a substantially scissor-shaped catcher 43. There is.

The nose 42 is connected to the screw supply device by a tube (not shown) or the like. The nose 42 is open near the tip of the main body 41. Further, the catcher 43 is composed of a left catcher piece 431 and a right catcher piece 432 having the same shape as the left catcher piece 431, and these catcher pieces 431, 432 are rotatably supported by the main body 41 by shafts 441, 442, respectively. . Further, springs 451 and 452 are interposed between the main body 41 and the catcher 43.
, 452 always urges both catcher pieces 431, 432 to a direction in which their tips are closed. Also, the left catcher piece
Near the tip of 431, a substantially boomerang-shaped return prevention pawl 431c is pivotally supported via a spring 431d. The anti-return claw 431c is provided with a screw 90 supplied through the nose 42.
It is to prevent it from returning again.

Next, the operation of the automatic screw tightener having the above configuration will be described.

First, the screw 90 is supplied from the screw supply device to the chuck unit 40 by compressed air through the nose 42. At this time, the supplied screw 90 passes through the return prevention pawl 431c and the catcher
It is clamped at the tip of 43 (see FIGS. 6 and 7).

Next, the first cylinder 20 operates to move the adsorption pipe 60 downward. At this time, since the suction device vacuums, the screw 90 is sucked into the suction pipe 60 and fits into the tip of the included driver bit 50. In this case, the return prevention claw 431c is pushed away in the direction of arrow A in FIG. 7 by the suction pipe 60 moving downward.

In this state, the second cylinder 30 is operated, and the suction pipe 60 and the driver bit 50 are further moved downward via the operating rod 31. Then, the tip of the suction pipe 60 is caught by the catcher 43.
To the left and right, and the tip of the suction pipe 60 is
Project outwards. At this time, the drive source 10 is assumed to be rotationally driven.

Here, the suction pipe 60 is moved upward by the first cylinder 20, and the second base is moved by the second cylinder 30.
When 80 is moved further downward, the driver bit 50 having a screw 90 at its tip will come out of the suction pipe 60. In this state, the workpiece of the leg portion 91 of the screw 90 (not shown) is brought into contact with a screw hole that is previously opened, and the screw 90
Is screwed onto the work.

When the one-cycle operation as described above is completed, the driver bit 50 returns to the inside of the suction pipe 60 again, and the suction pipe 60 moves upward to prepare for the next operation.

<Problems to be Solved by the Invention> However, the chuck unit of the conventional automatic screw tightener having the above-described configuration has the following problems.

When the dimension of the leg portion 91 is extremely shorter than the diameter of the head portion of the screw 90 supplied, as shown in FIG.
The screw 90 supplied at the portion opened to the end rotates, and the tip of the catcher 43 cannot be properly clamped, and the screw is clogged. In such a state, the operation of the automatic screw tightening machine must be stopped, and the worker must push the catcher 43 open to remove the jammed screw 90.

The present invention has been devised in view of the above circumstances, and provides a chuck unit for an automatic screw tightener that allows a catcher to pinch a screw whose leg size is extremely shorter than the head diameter. It is intended to be provided.

<Means for Solving Problems> A chuck unit of an automatic screw tightener according to the present invention includes a driver bit for screwing a screw supplied from a screw supply device to a work, a driver bit included and the screw. It is provided at the tip of an automatic screw tightener that has a suction pipe that sucks and fits into the tip of the driver bit, and even if the screw has an extremely short leg dimension compared to the head diameter, it can be clamped. A chuck unit of an automatic screw tightener capable of being provided with a main body having a nose inclined with respect to a driver bit, a pair of opposed catchers having tips attached to the main body so as to be able to come into contact with and separate from the main body, and provided inside the catcher. , A pair of opposed guide claws whose tip is attached to the main body so that the tip can come into contact with and separate from the main body. There is a cutout part that forms a space with the same inclination and the same diameter, and the screw supplied from the screw feeder via the nose with the legs in front of the screw is attached to the tip of the guide claw via the cutout part. The screw is sandwiched, and the screw is sucked into a suction pipe that is processed while expanding the guide claw together with the driver bit to fit into the tip of the driver bit, and the catcher is spread by the descending suction pipe.

<Operation> Screws are supplied from the screw supply device to the chuck unit by compressed air through the nose. At this time, the screw that has passed through the nose passes through the hollow portion formed on the guide claw and is supplied to the tip of the guide nail, that is, the end portion of the hollow portion, and at the same time, the guide nail whose tip is closed by the spring. Is opened by compressed air. Further, the screw is clamped by the catcher.

Next, the suction device operates and the suction pipe moves downward to push the guide claws apart. Therefore, the screw clamped by the catcher is sucked into the suction pipe. Since the driver bit is included in this suction pipe,
The screw fits into the tip of the driver bit.

In this state, the driver bit and the suction pipe simultaneously move downward. Therefore, the catcher is pushed and spread by the tip of the suction pipe, and the suction pipe including the driver bit and the screw projects from the catcher.

Then, while holding the suction pipe as it is, only the driver bit is moved further downward. Therefore, the driver bit having the screw fitted at the tip projects from the suction pipe. In this state, the driver bit is rotatingly driven. Therefore, the screw is screwed into the screw hole previously opened in the work.

<Embodiment> An embodiment according to the present invention will be described below with reference to the drawings.

1 is a front view of a chuck unit of an automatic screw tightener according to the present invention, FIG. 2 is a sectional view thereof, and FIG. 3 is A of FIG.
FIG. 4 is a cross-sectional view taken along line A, and FIG. 4 is an exploded perspective view of the guide claws and the catcher of the chuck unit. The same members as those in the chuck unit of the conventional automatic screw tightening machine described above are represented by the same numbers.

The automatic screw tightener to which the chuck unit 40 of the automatic screw tightener according to the present invention is attached is the same as that described in the section of the related art. In other words, this automatic screw tightener uses a drive source such as a motor that drives the driver bit 50 to rotate.
10 and the first cylinder 20 that moves only the suction pipe 60 up and down
A second cylinder 30 for vertically moving the driver bit 50 and the suction pipe 60; and a chuck unit 40 for holding a screw 90 supplied from a screw supply device (not shown).

The chuck unit 40 is attached to the tip of the second base 70, and the second cylinder 30 is attached to the other end. A first base 80 is attached to the tip of an elongated U-shaped operating rod 31 that transmits the operation of the second cylinder 30 by screwing or the like. The drive source 10 and the first cylinder 20 are attached to the first base 80. In other words, this first base 80 is the second cylinder
It can be moved up and down by 30.

The driver bit 50 is connected to the main shaft 11 of the drive source 10 and is also included in the suction pipe 60. The suction pipe 60 is connected to a suction device (not shown) and can be moved up and down by the first cylinder 20. The tip of the suction pipe 60 is formed to be slightly thin.

The chuck unit 40 of the automatic screw tightener according to the present invention has a substantially L-shape, and has a main body 41, a nose 42, a catcher 43, and a guide claw 46.

The main body 41 has the driver bit 50 and the suction pipe 60 inserted therein, and is attached to the tip of the second base 70 by screwing or the like.

The nose 42 guides the screw 90 supplied from the screw supply device to the vicinity of the tip of the chuck unit 40, and opens in the vicinity of the tip of the main body 41. The nose 42 is inclined with respect to the main body 41.

The catcher 43 has a substantially scissor-like shape. That is, the catcher 43 is configured by a pair of left catcher piece 431 and right catcher piece 432 facing each other, and the shaft 441,
442 is pivotally supported on the main body 41, and both catcher pieces 431,
The tip of the 432 can be moved freely. The catcher pieces 431 and 432 are symmetrically formed, and openings 431a and 432a are formed therein. The guide claw 46 described later is set to fit into the openings 431a and 432a.
Furthermore, recesses 431b and 432b corresponding to the diameter of the leg portion 91 of the screw 90 to be supplied are formed at the tips of the catcher pieces 431 and 432, respectively.

The guide claw 46 is the opening 431 of the both catcher pieces 431 and 432b.
Like the catcher 43, it is fitted into the a and 432a and is formed into a substantially scissor-like shape. That is, this guide claw
Similarly to the catcher 43, 46 is also composed of a pair of left guide claws 461 and right guide claws 462 facing each other. The ends of the guide claws 461 and 462 are pivotally supported by the main body 41 by the shafts 441 and 442 so that the tips of the guide claws 461 and 462 can be moved toward and away from each other. The two guide claws 461 and 462 are formed symmetrically with each other, and a hollow portion 47 is formed across the both guide claws 461 and 462. This hollow part 47 is the main body 41
When the guide claw 46 is fitted to the catcher 43 attached to the, it is formed to have the same inclination as the inclination of the nose 42. That is, for the screw 90 supplied from the screw supply device, the hollow guide claw 46 having the same diameter and the same inclination as the nose 42.
This is equivalent to continuing inside (see Fig. 2). Further, a recess 461a is formed at the end of the hollow portion 47,
462a is formed respectively.

The catcher 43 and the guide claw 46 are axially supported by the main body 41 by the shafts 441 and 442 as described above, and the springs 451 and 452 are provided between the main body 41 and the catcher 43 and the main body 41.
Springs 453 and 454 are interposed between 41 and the guide claw 46. The catcher 43 and the guide claw 46 are elastically urged by the springs 451 to 454 so that the tips thereof are always closed.

Next, the chuck unit of the automatic screw tightener according to the present invention
The operation of 40 will be described.

The screw 90 is supplied to the chuck unit 40 from the screw supply device by compressed air. At this time, the screw 90 that has passed through the nose 42 passes through the cutout portion 47 and is supplied to the tip of the guide claw 46, that is, the end portion of the cutout portion 47, and at the same time, the tip is closed by the springs 453 and 454. The guide claw 46 is opened by the force of the compressed air, and the screw 90 is sandwiched between the recesses 431b and 432b of the catcher 43.

Here, since the cutout portion 47 is formed to have the same inclination and the same diameter as the nose 42, it is the same as the nose 42 being provided up to the tip of the guide claw 46. For this reason, even if the screw supplied from the screw supply device has a leg whose dimension is extremely shorter than the diameter of the head, the cut-out portion 47.
It does not rotate with the
It will be sandwiched between 31b and 432b.

Next, the suction device is activated, and the suction pipe 60 moves downward to spread the guide claw 46. Therefore, the screw 90 held by the catcher 43 is sucked into the suction pipe 60. Since the suction pipe 60 contains the driver bit 50, the screw 90 is fitted into the tip of the driver bit 50.

In this state, the driver bit 50 and the suction pipe 60 simultaneously move downward. Therefore, the catcher 43 is attached to the suction pipe 60.
It will be spread at the tip of the driver bit 50
The suction pipe 60 including the screw 90 and the screw 90 projects from the catcher 43.

Next, the suction pipe 60 is held as it is, and only the driver bit 50 is moved downward.
Therefore, the driver bit 50 with the screw 90 fitted at the tip projects from the suction pipe 60. In this state, the driver bit 50 is rotationally driven. Therefore, the screw 90 is screwed into the screw hole previously opened in the work.

<Effects of the Invention> According to the chuck unit of the automatic screw tightener according to the present invention, the guide claw having the cutout portion having the same diameter and the same inclination as the nose with respect to the screw supplied from the screw supply device is fitted to the catcher. Since the screws are combined, the screw does not rotate at the end portion of the nose, that is, the opening portion of the nose, even if the size of the leg portion is extremely shorter than the diameter of the head portion. Therefore, even such a screw can be securely screwed.

Therefore, the work is not interrupted during the screwing work.

[Brief description of drawings]

1 is a front view of a chuck unit of an automatic screw tightener according to the present invention, FIG. 2 is a sectional view thereof, and FIG. 3 is A of FIG.
Fig. 4 is a sectional view taken along line A, Fig. 4 is an exploded perspective view of the guide claws of the chuck unit and the catcher, and Fig. 5 is an automatic screw tightener for explaining the outline of the automatic screw tightener common to the conventional and the present invention. Partially broken side view, FIG. 6 is an enlarged view of part a in FIG. 5, FIG. 7 is a cross section taken along the line BB in FIG. 6, and FIG. 8 is a description of problems of the conventional automatic screw tightening machine. FIG. 40 …… Chuck unit, 41 …… Main body, 42 …… Nose,
43 …… Catcher, 46 …… Guide claw, 47 …… Hollow-out part,
50 …… Driver bit, 60 …… Suction pipe, 90 …… Screw.

Claims (1)

[Claims] 1. An automatic screw tightening having a driver bit for screwing a screw supplied from a screw supply device to a work, and a suction pipe which contains the driver bit and sucks the screw to fit the tip of the driver bit. A chuck unit of an automatic screw tightener that is provided at the tip of the machine and that can clamp even a screw whose leg size is extremely short compared to the diameter of the head. A main body having, a pair of opposed catchers whose tips are attached to the main body so that their tips can be brought into contact with and separated from each other, and a pair of opposed guide claws which are provided inside the catcher and whose tips are attached to be detachable from the body. The guide claw is provided with a cutout portion that forms a space of the same diameter and the same inclination as the nose with the tip closed. The screw supplied from the screw feeder with the legs in front is clamped by the tip of the guide claw through the cutout part, and the screw is held in the suction pipe that descends while spreading the guide claw together with the driver bit. A chuck unit for an automatic screw tightener, which is sucked and fitted into the tip of a driver bit, and the catcher is spread by a descending suction pipe.