JPH0871935A - Screw feed mechanism in thread fastening machine for connecting screw - Google Patents

Abstract

PURPOSE: To surely feed a connecting screw by invariably rotating a feeding wheel at a specific rotating angle. CONSTITUTION: An engaging pin 18 energized so as to engage with a feed hole 11 is provided at one end of a feed plate 12, and a feeding wheel 6 is rotated in a state where the engaging pin 18 of a feed plate 12 interlocked by pressedly moving a nose part 2 to a thread fastening machine body 1 engages the feed hole 11 for feeding a connecting screw 5 in the extending direction of a driver bit 3. When the nose part 2 is moved in a reverse direction, the engaging pin 18 slips out of the feed hole 11 in a state where the reverse rotation of the feeding wheel 6 is prevented, and is engaged with a feed hole 11 at the second place, and at the same time, a guide plate 22 which fits on the engaging pin 18 and guides it so that it may move on the feed hole 11 is supported on a rotating shaft 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screw tightening machine for connecting screws, in which a feed wheel rotatably arranged on a nose part is rotated in conjunction with pushing and moving the nose part into the screw tightener body. The present invention relates to a screw feeding mechanism that feeds a connecting screw.

[0002]

2. Description of the Related Art As shown in FIG. 7, a conventional screw feeding mechanism of this type forms a curved ridge 31 extending radially from the center on a side surface of a feed wheel 30 and tightening a nose portion with a screw. The feed wheel 30 is rotated by a predetermined rotation angle by engaging and pushing the engaging roller 33 of the feed plate 32 which is interlocked by being pushed and moved to the machine body.

However, in such a feeding mechanism,
When a little great resistance is applied to the rotation of the feed wheel 30, the engagement roller 33 moves as shown by the dotted line, and a predetermined rotation angle cannot be realized, resulting in insufficient feed.

[0004]

SUMMARY OF THE INVENTION The present invention solves the above problems and provides a screw feeding mechanism in a screw tightening machine for a coupling screw, which is capable of reliably feeding a coupling screw by always rotating a feed wheel at a predetermined rotation angle. The purpose is to do.

[0005]

In order to achieve the above object, a screw feed mechanism in a screw tightener for connecting screws according to the present invention has a shaft of the screwdriver bit at the front of a screwdriver main body provided with a screwdriver bit. In a screw tightener that has a movable nose part and a feed wheel that feeds a connecting screw to the nose is rotatably installed, at one end of the feed plate that interlocks with the relative movement of the screw tightener body and the nose part. , A nose provided with an engagement pin that is movable in the engagement / disengagement direction with respect to the feed holes formed at equal intervals in the circumferential direction on the side surface of the feed wheel and is urged to always engage with the feed hole. The drive wheel is rotated with the engaging pin of the interlocking feed plate engaged with the feed hole by pushing and moving the part to the screw tightener main body, and the connecting screw is screwed into the driver bit. When the nose part is moved in the opposite direction from this state, the engaging pin disengages from the feed hole and engages with the next feed hole when the feed wheel is prevented from rotating in the reverse direction. In addition, the guide plate is rotatably supported on the rotation shaft of the feed wheel, the guide plate being fitted to the engagement pin and guiding the engagement pin to move on the feed hole. .

[0006]

According to the above construction, when the screw tightener main body is pushed forward and the tip of the nose portion is pressed against the material to be screwed during the screw tightening work, the nose portion moves relatively rearward and is interlocked with this relative movement. The engaging pin at the end portion of the feed plate feeds the feed wheel in the screw feed direction in the state of being engaged with the feed hole of the feed wheel by one screw of the connecting screw in the extension direction of the axis of the driver bit. When the main body of the screw tightener is further pressed forward, the driver bit engages with the fed screw and is screwed into the material to be screwed while rotating.

When the screw tightener is released from the screw after screwing in, the nose portion returns to its original position, and in conjunction with this, the engaging pin of the feed plate is removed from the feed hole and then rotated by the guide plate. Is guided to move around and moves onto the next perforation hole and engages this perforation hole to prepare for the next feed.

[0008]

1 (a) and 1 (b) show a front portion of a screw tightening machine, wherein reference numeral 1 is a screw tightening machine main body, and 2 is a nose portion. The screw tightener main body 1 includes a driver bit 3 and a rotation driving mechanism (not shown) for the screw bit, and the nose portion 2 is movable in the axial direction of the driver bit 3, and the rotary shaft 4 supported on both left and right sides. Feed wheel 6 that feeds connecting screw 5 from bottom to top
Are provided rotatably. The feed wheel 6 is configured to be rotatable on only one side.

The nose portion 2 is constantly urged by a spring 7 so as to move forward away from the screw tightener body 1.

The rotating shaft 4 has a large diameter at the center and small diameters at both ends, and a groove 8 is formed on the peripheral surface of one small diameter portion 4a in parallel with the axial direction. As shown in FIG. 2, the end portion having the concave groove 8 is fitted to the convex strip 9a of the bearing portion 9 of the nose portion 2, and the rotary shaft 4 is arranged so as not to rotate. Further, the ratchet-shaped claw portion 10 is circumferentially provided on the peripheral surface on one side of the large diameter portion 4b.
Are formed.

On the side surface of the feed wheel 6, feed holes 11 are formed at equal intervals in the circumferential direction. The wall 11a at the end of the feed hole 11 on the feed side (see FIG. 3) is formed at a right angle to the side surface, and the wall 11b on the opposite side is formed to be inclined. A feed plate 12 is arranged between the screw tightener body 1 and the nose portion 2. A roller 14 axially attached to one end of the feed plate 12 is movably engaged with a guide groove 15 formed on a side portion of the screw tightener body 1 and a guide groove 16 formed on a side portion of the nose portion 2. An engaging pin 18 is slidably provided on the bush 17 at the other end of the feed plate 12. 3 and 4, the engagement pin 18 includes a head portion 18a formed to engage with the feed hole 11, a shaft portion 18b and a head portion 18a housed in the bush 17 claw. It is composed of a collar portion 19 provided between the shaft portion 18b and the shaft portion 18b. The engagement pin 18 is movable in the engagement / disengagement direction with respect to the feed hole 11, and is always engaged with the feed hole 11 by the spring 20 arranged between the feed plate 12 and the collar portion 19. Is urged by. 21 is a retainer.

Next, a guide plate 22 rotatably supported on the rotary shaft 4 of the feed wheel 6 is arranged on the feed hole 11 side of the feed wheel 6. A part of the guide plate 22 bulges out, and a fitting hole 23 into which the engaging pin 18 is fitted is formed in the bulging portion 22a. Therefore, the engagement pin 18 is guided so as to move along the circumference connecting the feed holes 11. The guide plate 22 is biased by a spring 24 so as to come into contact with the side surface of the feed wheel 6.

Further, as shown in FIG. 6, a recess 25 is formed on the side surface on the opposite side of the feed wheel 6, and a support shaft 26 is provided in the recess 25, and a check claw 27 is rotated on the support shaft 26. It is attached freely. The check claw 27 is arranged at a position corresponding to the claw portion 10 of the rotary shaft 4, and is biased by the spring 28 provided in the recess 25 so as to be engaged with the claw portion 10 of the rotary shaft 4. A cover plate 29 for pressing the check claw 27 is superposed on the side surface of the feed wheel 6.

In the above structure, when screw tightening work is performed, the screw tightener main body 1 is pushed forward and the tip of the nose portion 2 is pressed against the material 30 to be screwed, as shown in FIGS.
The nose portion 2 moves relatively rearward, and the roller 1 at one end of the feed plate 12 interlocks with this relative movement.
4 is guided by the guide groove 16 of the nose part 2 and the inclined short groove part 15a of the guide groove 15 of the screw tightener main body 1, and the moving amount of the nose part 2 in the moving direction is larger than that of the nose part 2. Since it is small, the engaging pin 18 at the other end of the feed plate 12 presses the feed wheel 6 in the direction opposite to the moving direction of the nose portion 2 while being engaged with the feed hole 11 of the feed wheel 6. Therefore, the feed wheel 6 rotates in the feed direction by a rotation angle corresponding to feeding one screw of the connecting screw 5 in the extension direction of the axis of the driver bit 3.
When the screw tightener main body 1 is further pressed forward, the driver bit 3 engages with the delivered screw, and while screwing it, the driver bit 3 is screwed into the material to be screwed. At this time, the roller 14 of the feed plate 12 has the guide groove 1
5 along the long groove portion 15b.

When the screw tightener is released from the screw after screwing in, the nose portion 2 returns to its original position by the spring 7, so that the roller 14 of the feed plate 12 finally reaches the inclined short groove 15a of the guide groove 15 and the nose portion. The guide pin 16 is moved by being guided by the guide groove 16 of No. 2 but is smaller than the moving amount of the nose portion 2 in the moving direction. This sprocket hole 1 moves along the wall 11b (see FIG. 3).
After separating from 1, the guide plate 22 guides it to move around the rotary shaft 4 and moves it to the next feed hole 11, and the spring 20 engages this feed hole 11 to move the next feed. Be prepared.

When the engagement pin 18 moves so as to engage with the next-order feed hole 11, a force acts so that the feed wheel 6 reverses. In this case, as shown in FIG. Two
Since the spring 7 engages the claw portion 10 of the rotary shaft 4 with the spring 28, the reverse rotation of the feed wheel 6 is prevented. When the feed wheel 6 rotates in the feed direction, the non-return pawl 27 has the pawl portion 10.
The feed wheel 6 can rotate because it is not locked to.

[0017]

According to the present invention, the engaging pin of the feed plate is configured to be engaged with and disengaged from the hole formed on the side surface of the feed wheel, and the engaging pin keeps the engaged state at the time of feeding and the wall of the feed hole is formed. Rotate the feed wheel while pressing. Even if a resistance is applied to the rotation of the feed wheel and a force acts so that the engagement pin disengages from the feed hole, the movement of the engagement pin is restricted by the guide plate so that it cannot move in directions other than the feed direction. Therefore, the engagement between the engagement pin and the feed hole is ensured by the guide plate, and the fall of the engagement pin or the movement of the engagement pin in a direction other than the feeding direction is prevented. Therefore, the engagement pin can always rotate the feed wheel by a predetermined rotation angle.

Further, even after the engagement pin has been rotated by the feed wheel by a predetermined rotation angle, the engagement pin is guided by the guide plate and reliably moves to the next feed hole.

Therefore, according to the present invention, the connecting screw can be reliably fed.

[Brief description of drawings]

1A and 1B are a plan view and a side view before screw feeding of a screw feeding mechanism of a screw fastening machine for connecting screws according to the present invention.

FIG. 2 is an explanatory view of a bearing aspect of a rotating shaft

FIG. 3 is an explanatory view of a manner of detaching an engagement pin from a feed hole in the screw feed mechanism.

FIG. 4 is an exploded perspective view of an engagement pin and a guide plate in the screw feeding mechanism.

5 (a) and 5 (b) are a plan view and a side view of the above-described screw feeding mechanism at the time of screw feeding.

FIG. 6 is a side view of the reverse rotation prevention mechanism of the feed wheel.

FIG. 7 is an explanatory view of a main part of a conventional screw feeding mechanism.

[Explanation of symbols]

 1 Screw Tightening Machine Main Body 2 Nose 4 Rotating Shaft 5 Connecting Screw 6 Feed Wheel 11 Feed Hole 12 Feed Plate 18 Engagement Pin 22 Guide Plate

Claims (1)

[Claims] 1. A screw tightener in which a nose portion that is movable in the axial direction of the driver bit is provided in the front portion of a screw tightener main body equipped with a driver bit, and a feed wheel that feeds a connecting screw to the nose portion is rotatably provided. In the machine, one end of the feed plate that is interlocked with the relative movement of the screw tightener body and the nose part moves in the engagement / disengagement direction with respect to the feed holes formed at equal intervals in the circumferential direction on the side surface of the feed wheel. It is possible to provide an engaging pin that is urged to always engage with the feed hole, and the engaging pin of the interlocking feed plate moves into the feed hole by pushing and moving the nose part against the screw tightener body. Rotate the feed wheel in the engaged state to feed out the connecting screw in the extension direction of the driver bit shaft, and when the nose part is moved in the opposite direction from this state, the feed wheel In the state where the rolling is prevented, the engaging pin is detached from the feed hole and engaged with the next feed hole, and the rotation shaft of the feed wheel is fitted with the engagement pin and the engagement pin. A screw feed mechanism in a screw tightener for connecting screws, wherein a guide plate that guides the guide to move on the feed hole is rotatably supported.