JP3044148B2 - Screw fastening device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screw tightening device for screwing a supplied screw to a work, and more particularly to a technique for screwing a screw while favorably aligning the screw with the work. is there.

[0002]

2. Description of the Related Art Conventionally, in a screw tightening apparatus for tightening a work with a bit B while holding a supplied screw N, as shown in Japanese Patent Application Laid-Open No. 2-145224 shown in FIG. While holding the screw N sent in by the screw holder 3a, the bit B is lowered and pressed against the head of the screw N, and the bit B is rotated to fasten the screw N to the work.

[0003]

However, in such a configuration, the screw N is held by the screw holder 3a in a suspended manner at the head of the screw N. Since the tip of the screw N is not positioned, it is difficult to determine the position of the tip of the screw N, and there is a problem that a fastening failure is likely to occur when the screw is tightened to the work. Further, since the holding of the screw N and the positioning of the work are performed in separate systems, it is difficult to position the screw N and the work, and in this respect, there is a problem that the screwing failure is likely to occur.

The present invention has been made in view of such a problem, and an object of the present invention is to easily and surely position a screw and a work, to avoid poor screw tightening, and to achieve good screw tightening. An object of the present invention is to provide a screw tightening device that can perform the screw tightening.

[0005]

SUMMARY OF THE INVENTION The present invention relates to a screw fastening device for fastening a work W with a bit B while holding a screw N to be supplied. The work W to be screwed is grasped and held. Positioning in which a work holding part 1, a screw guide part 2 for guiding a screw N with respect to a work W held by the work holding part 1, and a screw holding part 3 for positioning and holding the supplied screw N are formed. The tool 4 is provided so as to be positioned with respect to the bit B, and is configured to be openable and closable in a plane substantially perpendicular to the direction in which the bit B is moved up and down.

Further, the screw guide portion 2 may be formed in a tapered hole having inclined surfaces 12. Also,
The screw N supplied from the screw chute 6 may be received by the screw catcher 7, the screw catcher 7 may be opened, the screw N may be supplied to the screw guide 2 of the positioning tool 4, and then the screw may be tightened. It is.

The tip of the bit B is eccentric with respect to the base end. The bit guide 16 has a tapered hole 17 for guiding the tip of the bit B, and an intermediate portion between the bit B and the bit. At the center of B, a straight hole 18 for rotatably holding may be formed. The positioning tool 4 may open and close the open / close claws 11, 11 of the positioning tool 4 before the head of the screw N hits the tapered hole.

The positioning tool 4 may be configured to guide the tip of the screw N and the outer periphery of the head in the tapered hole. The hole of the screw guide portion 2 of the positioning tool 4 may have a tapered hole at the upper end and a lower end, and a linear hole at the middle. Further, the number of the open / close claws 11 of the positioning tool 4 may be three.

Further, a vibration applying means for applying vibration to the positioning tool 4 may be provided. Further, an air blowing means may be provided to the positioning tool 4. The inner surface of the positioning tool 4 may be coated with a wear-resistant material such as a ceramic or titanium coating, or may be subjected to a wear-resistant treatment.

[0010]

The work W is held in the work holding portion 1 of the positioning tool 4 by opening and closing the positioning tool 4 aligned with the bit B. The screw N supplied in the screw guide 2 is guided to the work W. The screw N is held at a predetermined position in the screw holding section 3.
In such a positioning state of the screw N and the work W, the screw N is tightened to the work W as predetermined.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is an overall perspective view, in which an outer cylinder 5 is arranged around the bit B, a screw chute 6 is connected to the outer cylinder 5, and a screw catcher 7 is provided at a lower end of the outer cylinder 5. A pair of opening and closing members 7a, 7a are provided so as to be openable and closable,
The head unit 8 in which the outer cylinder 5 and the screw catcher 7 are integrated can be moved up and down, and the bit B can be driven and rotated and independently moved up and down inside the outer cylinder 5.

The screw N supplied from the screw chute 6 passes through the inside of the outer cylinder 5 and is held by the screw catcher 7 with its head suspended and the head 8 is moved downward.
The catcher 7 opens and the screw N is positioned as described below.
The bit B is lowered and the screw N
The screw is tightened by engaging with the groove of the head. In such a case, the open / close members 7a of the screw catcher 7 are opened / closed by rotating the shafts 9, 9 via a rack and pinion mechanism. The opening and closing mechanism of the opening and closing members 7a, 7a can be variously changed in design.

In the present invention, when the screw N is screwed to the work W, the screw N is satisfactorily tightened while positioning the screw N with the work W. Such a structure will be described in detail below. . Positioning tool 4
As shown in FIG. 1, is disposed above a work positioning device 10 that positions the work W below the head unit 8. The positioning tool 4 includes left and right opening / closing claws 11, 11, and can be opened and closed by an opening / closing cylinder 13 in a horizontal plane substantially perpendicular to the direction in which the bit B is raised and lowered. The opening / closing claws 11, 11 are formed with tapered inclined surfaces 12, 12, and when the opening / closing members 7a, 7a of the screw catcher 7 are opened in the closed state of the opening / closing claws 11, 11, the screw N supplied by dropping is supplied. The head and its tip can be guided and held by tapered inclined surfaces 12,12. The configuration for guiding the screw N as described above is referred to as a screw guide portion 2, and the configuration for holding the guided screw N is referred to as a screw holding portion 3.

A screw fastening part a having a substantially U-shaped cross section is attached to the workpiece W. Side positioning. A configuration for performing positioning with respect to the work W in this manner is referred to as a work holding unit 1. The work W to which the screw fastening parts a are attached is conveyed, for example, on a conveyor, and the opposing positioning pins 1
The work W can be positioned by the protrusions 4. The design of such a work positioning device 10 can also be variously changed.

Thus, the screw is tightened by the operation shown in FIG. That is, as shown in FIGS. 7A and 7B, the head 8 is lowered while the screw N is being held by the screw catcher 7, and the center of the head 8 is substantially aligned with the bit B. The opening and closing claws 11 of the positioning tool 4 are closed, and the positioning of the positioning tool 4 is performed by clamping the projecting portion b of the screw fastening part a on the work W side by the work holding part 1 (see FIG. ) (D)). Then, the head portion 8 is lowered, and the screw catcher 7 is opened while the screw N is inserted into the hole between the tapered inclined surfaces 12, 12 of the positioning tool 4, and guided by the tapered inclined surfaces 12, 12. The screw N is aligned with the screw hole of the screw fastening part a on the workpiece W side, and the head of the screw N is held at the intermediate portion between the tapered inclined surfaces 12, 12. Retained ((G) in the same figure)
(H)). In this state, the bit B descends and the screw N
The screw N is screwed into the screw fastening part a by the driving rotation of the bit B, and the screw is fastened to the work W. In such a case, the opening and closing claws 11, 11 of the positioning tool 4 are opened in a timely manner as the screw N is tightened ((K) and (L) in the figure).

As described above, the work holding portion 1 for grasping and holding the work W to be screwed and the screw guiding portion 2 for guiding the screw B to the work W held by the work holding portion 1.
And a screw holder 3 for positioning and holding the supplied screw B.
And a positioning tool 4 formed with the bit B is provided so as to be positioned with respect to the bit B, and is configured to be openable and closable in a plane substantially perpendicular to the direction in which the bit B is raised and lowered.
By opening and closing the positioning tool 4 aligned with the bit B, the work W is held in the work holding unit 1 of the positioning tool 4 and the screw N supplied in the screw guide unit 2 is moved to the work W side. The screw N is held at a predetermined position in the screw holding section 3 and the screw N can be tightened to the work W in such a state that the screw N and the work W are positioned. It is suppressed.

FIG. 3 shows a second embodiment, in which bit B
Is formed eccentrically by a flexible joint 15, for example, a bit guide 16 is disposed below the bit B and above the positioning tool 4, and a tapered hole 17 is formed in the bit guide 16, and the tapered hole 17 Bit B
The bit B is rotatably held at its center in the linear hole 18 of the bit guide 16, and is supplied from the screw catcher 7 to the positioning tool 4, and the screw N is driven to rotate by the bit B to perform positioning. Screw fastening is performed in the same manner as in the above embodiment in which the screw N side and the work W side are positioned by the tool 4.

FIG. 4 shows a third embodiment. The positioning tool 4 controls the opening and closing of the open / close claws 11 of the positioning tool 4 before the head of the screw N of the tapered hole hits. FIG. 5 shows a fourth embodiment, in which the positioning tool 4 guides the distal end of the screw N and the outer periphery of the head in the tapered hole. FIG. 6 shows a fifth embodiment, in which the upper and lower ends of the hole of the screw guide 2 of the positioning tool 4 are formed as tapered holes, and the intermediate portion is formed as a straight hole. . In this embodiment, the tip and the head of the screw N are guided by the tapered holes 19 and 20, and the screw N is held substantially vertically in the straight hole 21 in the middle without applying excessive force to the positioning tool 4. You can do it.

FIG. 7 shows a sixth embodiment, in which the positioning tool 4 has three open / close claws 11. By using three open / close claws 11 in this manner, the screw N can be always held on three surfaces, and screw tightening is stabilized. FIG. 8 shows a seventh embodiment, in which vibration is applied by a vibration applying means for applying vibration to the positioning tool 4 so that the screw N in the positioning tool 4 can be positioned more favorably.

FIG. 9 shows an eighth embodiment, in which an air blowing means is provided to the positioning tool 4 and air is blown from the air blowing means.
The position of the screw N in the positioning tool 4 by the blown air
The arrangement can be performed better . The inner surface of the positioning tool 4 may be coated with a wear-resistant material such as a ceramic or titanium coating, or may be subjected to a wear-resistant treatment.

[0021]

According to the present invention, as described above, a work holding portion for grasping and holding a work to be screwed and a screw guide for guiding a screw to the work held by the work holding portion are provided. A positioning tool formed with a screw holding portion for positioning and holding the screw is provided so as to be aligned with the bit, and is configured to be openable and closable in a plane substantially orthogonal to the vertical direction of the bit. By opening and closing the positioning tool positioned with respect to the bit, the work is held in the work holding part of the positioning tool, the screw supplied in the screw guide is guided to the work side, and the screw is held in the screw holding part. In a predetermined position, and in such a positioning state of the screw and the work, the screw can be tightened to the work as predetermined,
There is an advantage that insufficient fastening can be sufficiently suppressed.

[Brief description of the drawings]

FIG. 1 is an overall perspective view of one embodiment of the present invention.

FIG. 2 shows the same screw tightening action as in the above (A) to (N).
Is a process drawing.

3A and 3B show a second embodiment of the above, wherein FIG.
(B) is an exploded perspective view.

FIG. 4 is a sectional view showing a third embodiment of the same.

FIG. 5 is a sectional view showing a fourth embodiment of the present invention.

FIG. 6 is a sectional view showing a fifth embodiment of the same.

FIG. 7 shows a sixth embodiment of the above, wherein (a) is a perspective view,
(B) is a plan view, and (c) is a cross-sectional view.

FIGS. 8A and 8B show a seventh embodiment of the present invention, wherein FIGS.
Is a cross-sectional view showing the operation.

FIG. 9 shows an eighth embodiment of the present invention, wherein (a) and (b)
Is a cross-sectional view showing the operation.

FIG. 10 is a side view of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Work holding part 2 Screw guide part 3 Screw holding part 4 Positioning tool 6 Screw chute 7 Screw catcher B Bit N Screw W Work a Screw fastening part b Projection

Continuation of the front page (56) References JP-A-1-109039 (JP, A) JP-A-2-145224 (JP, A) JP-A-60-191767 (JP, A) JP-A-63-116234 (JP) , U) Japanese Utility Model Application Hei 4-70432 (JP, U) Japanese Utility Model Application Showa 59-69827 (JP, U) Japanese Utility Model Application Hei 4-97621 (JP, U) (58) Fields surveyed (Int. Cl. ⁷ , DB Name) B23P 19/06

Claims (11)

(57) [Claims] 1. A screw tightening device for tightening a screw with a bit while holding a supplied screw,
A work holding portion that grips and holds the work to be screwed;
A positioning tool provided with a screw guide for guiding the screw to the work held by the work holding part and a screw holding part for positioning and holding the supplied screw is provided in alignment with the bit. A screw tightening device, which is configured to be openable and closable in a plane substantially perpendicular to a vertical direction of the bit. 2. The screw tightening device according to claim 1, wherein the screw guide is formed in a tapered hole having an inclined surface. 3. A screw catcher receives a screw supplied from a screw chute, opens the screw catcher, supplies the screw to a screw guide of a positioning tool, and then performs screw tightening. Or the screw fastening device according to claim 2. 4. The bit tip is made eccentric with respect to the base end. The bit guide has a tapered hole for guiding the bit tip, and the intermediate portion of the bit is rotatable at the center of the bit. 3. The screw tightening device according to claim 1, wherein a straight hole for holding the screw is formed. 5. The screw tightening device according to claim 1, wherein the positioning tool opens and closes the opening / closing claw of the positioning tool before the head of the screw hits the tapered hole. 6. The screw tightening device according to claim 1, wherein the positioning tool is configured to guide the tip of the screw and the outer periphery of the head in the tapered hole. 7. The hole of the screw guide portion of the positioning tool, wherein an upper end and a lower end of the hole are formed as tapered holes, and an intermediate portion is formed as a straight hole. The screw fastening device according to claim 2. 8. The screw tightening device according to claim 1, wherein the positioning tool has three open / close claws. 9. The screw tightening device according to claim 1, further comprising vibration applying means for applying vibration to the positioning tool. 10. The screw tightening device according to claim 1, wherein an air blowing means is provided to the positioning tool. 11. The screw fastener according to claim 1, wherein an inner surface of the positioning tool is coated with a wear-resistant material such as a ceramic or titanium coating or subjected to a wear-resistant treatment. apparatus.