JP7845262B2 - Fastening tool - Google Patents

Description

This invention relates to a fastening tool.

Conventionally, it is known that cleavage bolts are used to fasten two or more components together. A fastening tool is used to fasten the cleavage bolt. The fastening torque applied by the fastening tool causes the cleavage bolt to break, and the head of the cleavage bolt is severed. This severing of the head prevents the fastening of the components from being released.

Since it is undesirable to leave the head of a bolt on a component fastened with a bolt with a head-cutting mechanism, it is necessary to remove the severed head. In this regard, Patent Document 1 describes a method of holding the severed head in a fastening tool and removing the head from the fastening tool using the attractive force of a magnet provided in a separate retrieval device.

Japanese Patent Publication No. 2018-079536

However, providing a separate retrieval device from the fastening tools could increase production equipment costs and occupied space, potentially reducing production efficiency.

Therefore, in view of the above problems, the object of the present invention is to remove the severed head from a bolt without using any device other than the fastening tool.

The gist of this disclosure is as follows:

(1) A fastening tool used for fastening a slitting bolt, comprising: a tightening portion that engages with the head of the slitting bolt to apply tightening torque to the slitting bolt; a covering portion that covers the tightening portion; and an exposed portion that exposes the head of the slitting bolt remaining on the tightening portion due to fracture of the slitting bolt to the outside of the covering portion, wherein the exposed portion is slidable in the longitudinal direction of the fastening tool, and the sliding motion exposes the head to the outside of the covering portion.

(2) The fastening tool described in (1) above, wherein the head is held by a magnet at the fastening portion.

(3) The fastening tool described in (1) or (2) above, wherein the exposed portion presses against the head by a sliding motion.

(4) The fastening tool according to (1) or (2) above, wherein the covering portion functions as the exposed portion.

(5) A fastening tool according to any one of (1) to (4) above, further comprising a spring for biasing the exposed portion.

According to the present invention, the head severed from a bolt can be removed from the fastening tool without using any device other than the fastening tool.

Figure 1 shows a fastening tool according to the first embodiment of the present invention. Figure 2 is a cross-sectional view of a fastening tool that holds a neck-cutting bolt. Figure 3 is a cross-sectional view of the fastening tool after the head of the bolt has been cut off. Figure 4 is a cross-sectional view of the fastening tool when the support and sliding parts are moved to the proximal position. Figure 5 shows a fastening tool according to a second embodiment of the present invention. Figure 6 is a cross-sectional view of a fastening tool that holds a neck-cutting bolt. Figure 7 is a cross-sectional view of the fastening tool after the head of the bolt has been cut off. Figure 8 is a cross-sectional view of the fastening tool when the covering portion has moved to the distal position. Figure 9 shows a fastening tool according to a third embodiment of the present invention.

The embodiments of the present invention will be described in detail below with reference to the drawings. In the following description, similar components will be given the same reference numerals.

<First Embodiment>
The first embodiment of the present invention will be described below with reference to Figures 1 to 4. Figure 1 is a diagram showing a fastening tool 1 according to the first embodiment of the present invention. Figure 1(a) shows a front view of the fastening tool 1, and Figure 1(b) shows a cross-sectional view of the fastening tool 1 along the line A-A in Figure 1(a).

As shown in Figure 1, the fastening tool 1 comprises a clamping portion 2, a covering portion 3, a support portion 4, a sliding portion 5, a spring 6, and a tool mounting portion 7. The clamping portion 2 is formed as a recess and is defined by the covering portion 3 and the support portion 4.

The fastening tool 1 is used to fasten a neck bolt. Figure 2 is a cross-sectional view of the fastening tool 1 that holds the neck bolt 10. As shown in Figure 2, the neck bolt 10 consists of a head 11, a constricted portion 12, and a threaded portion 13. The threaded portion 13 has a threaded outer surface and is screwed into the component to be fastened by the neck bolt 10. The constricted portion 12 connects the head 11 and the threaded portion 13 and has a conical shape that tapers from the threaded portion 13 towards the head 11.

The head 11 has a hexagonal prism shape, and the tightening portion 2 has a hexagonal cross-section complementary to the head 11 to receive the head 11. The tightening portion 2 engages with the head 11 of the neck-cutting bolt 10 and applies tightening torque to the neck-cutting bolt 10.

When fastening the neck bolt 10 using the fastening tool 1, a tool such as an impact wrench (not shown) is attached to the tool mounting part 7. When the tool is driven, the fastening tool 1 rotates, and fastening torque is applied to the neck bolt 10 via the tightening part 2.

The covering portion 3 has a cylindrical shape and forms the outer surface of the fastening tool 1. The covering portion 3 covers the support portion 4, and the support portion 4 is held within the covering portion 3. The support portion 4 has a cylindrical shape and extends within the covering portion 3 in the longitudinal direction (axial direction) of the fastening tool 1. The support portion 4 supports the head 11 positioned on the tightening portion 2. In this embodiment, the support portion 4 is configured as a magnet (e.g., a permanent magnet) with magnetic force. When the head 11 of the neck-cutting bolt 10 is positioned on the tightening portion 2, the support portion 4 attracts the head 11 by magnetic force, and the head 11 is attracted to the support portion 4.

Figure 3 is a cross-sectional view of the fastening tool 1 after the head 11 of the cleavage bolt 10 has been cut off. When the fastening tool 1 is further rotated by the tool after the cleavage bolt 10 is fastened, the force attempting to rotate the head 11 relative to the constricting portion 12 and the threaded portion 13 causes the cleavage bolt 10 to break at the boundary between the head 11 and the constricting portion 12. As a result, as shown in Figure 3, the head 11 is separated from the remaining portion of the cleavage bolt 10 (the constricting portion 12 and the threaded portion 13) fixed to the member, and remains as a fragment in the fastening portion 2. In other words, the head 11 is cut off from the cleavage bolt 10.

In this embodiment, since the support portion 4 is configured as a magnet, the head portion 11 is held by the magnet at the fastening portion 2. Therefore, even when the fastening tool 1 is held so that the fastening portion 2 is positioned vertically downward, it is possible to prevent the head portion 11, severed from the shank bolt 10, from falling onto the member fastened by the shank bolt 10.

The sliding portion 5 has a cylindrical shape and slides on the covering portion 3. That is, the sliding portion 5 is slidable in the longitudinal direction of the fastening tool 1. As shown in Figure 3, the sliding portion 5 has a gripping portion 51, a movement restricting portion 52, and a fixing portion 53.

The gripping portion 51 is positioned on the covering portion 3 and is operated by the operator through gripping. The fixing portion 53 has a cylindrical shape and is positioned inside the covering portion 3. The fixing portion 53 is fixed to the support portion 4, and the sliding portion 5 moves integrally with the support portion 4.

The movement restricting portion 52 has a cylindrical shape and extends from the fixing portion 53 to the gripping portion 51 in the short-side direction (radial direction) of the fastening tool 1. A groove 31 defining the range of motion of the sliding portion 5 is formed in the covering portion 3. The movement restricting portion 52 is positioned in the groove 31 of the covering portion 3 and abuts against the end of the groove 31 to restrict the movement of the sliding portion 5.

The spring 6 is positioned inside the covering portion 3, around the support portion 4. One end of the spring 6 abuts against the inner wall of the covering portion 3, and the other end abuts against the fixing portion 53 of the sliding portion 5. The spring 6 expands and contracts between the sliding portion 5 and the covering portion 3 in the longitudinal direction of the fastening tool 1.

The support portion 4 and the sliding portion 5 are slidable in the longitudinal direction of the fastening tool 1. Specifically, the support portion 4 and the sliding portion 5 move linearly between a distal position far from the clamping portion 2 and a proximal position close to the clamping portion 2 in the longitudinal direction of the fastening tool 1. In this specification, the side of the fastening tool 1 closer to the clamping portion 2 is referred to as the proximal side, and the side of the fastening tool 1 far from the clamping portion 2 is referred to as the distal side.

As shown in Figures 1 to 3, when no force is applied to the sliding portion 5, the support portion 4 and the sliding portion 5 are positioned distally due to the biasing force of the spring 6. When the support portion 4 and the sliding portion 5 are in the distal position, the proximal end of the support portion 4 is separated distally from the proximal end of the covering portion 3, and a recess of the clamping portion 2 is formed on the proximal side of the support portion 4.

On the other hand, when a force is applied proximal to the slide portion 5 by the operator, the spring 6 is compressed by the slide portion 5. As a result, the support portion 4 and the slide portion 5 move from the distal position to the proximal position. Figure 4 is a cross-sectional view of the fastening tool 1 when the support portion 4 and the slide portion 5 have moved to the proximal position. The support portion 4 and the slide portion 5 press against the head 11 of the cleavage bolt 10 through their sliding motion. As a result, the head 11 moves proximal to the support portion 4 and is pushed out to the outside of the covering portion 3. In other words, in this embodiment, the support portion 4 and the slide portion 5 function as exposed parts that expose the head 11 remaining in the fastening portion 2 due to the fracture of the cleavage bolt 10 to the outside of the covering portion 3.

The head 11, exposed to the outside of the covering portion 3, is detached from the support portion 4 by the worker and collected in a collection container or the like. For example, the worker holds the sliding portion 5 proximal to the side with one hand and detaches the head 11 from the support portion 4 with the other hand. Therefore, according to this embodiment, the head 11 of the neck-cutting bolt 10 can be removed from the fastening tool 1 without using any devices other than the fastening tool 1. This reduces the cost and occupied space of production equipment and increases production efficiency.

After the head 11 is removed from the fastening tool 1, the worker releases their hand from the sliding part 5. As a result, the spring 6 biases the sliding part 5 distally, and the support part 4 and the sliding part 5 move from the proximal position to the distal position. Therefore, the support part 4 and the sliding part 5 can be automatically returned to their initial position (distal position), making it possible to quickly begin work on the next neck-cutting bolt 10 using the fastening tool 1.

<Second Embodiment>
Figure 5 shows a fastening tool 1' according to a second embodiment of the present invention. Figure 5(a) shows a front view of the fastening tool 1', and Figure 5(b) shows a cross-sectional view of the fastening tool 1' along the line B-B in Figure 5(a).

As shown in Figure 5, the fastening tool 1' comprises a clamping portion 2', a covering portion 3', a support portion 4', a spring 6', a tool mounting portion 7', a connecting portion 8, and a movement restricting portion 9. The clamping portion 2' is formed as a recess and is defined by the covering portion 3' and the support portion 4'.

Figure 6 is a cross-sectional view of the fastening tool 1' that holds the neck-cutting bolt 10. The head 11 of the neck-cutting bolt 10 has a hexagonal prism shape, and the tightening portion 2' has a hexagonal cross-section complementary to the head 11 to receive the head 11. The tightening portion 2' engages with the head 11 of the neck-cutting bolt 10 to apply tightening torque to the neck-cutting bolt 10.

When fastening the neck bolt 10 using the fastening tool 1', a tool such as an impact wrench (not shown) is attached to the tool mounting part 7'. When the tool is driven, the fastening tool 1' rotates, and fastening torque is applied to the neck bolt 10 via the tightening part 2'.

The covering portion 3' has a cylindrical shape and forms the outer surface of the fastening tool 1'. The covering portion 3' covers the support portion 4', and the support portion 4' is held within the covering portion 3'. The support portion 4' has a cylindrical shape and extends within the covering portion 3' in the longitudinal direction (axial direction) of the fastening tool 1'. The support portion 4' supports the head 11 positioned on the tightening portion 2'. In this embodiment, the support portion 4' is configured as a magnet (e.g., a permanent magnet) with magnetic force. When the head 11 of the neck-cutting bolt 10 is positioned on the tightening portion 2', the support portion 4' attracts the head 11 by magnetic force, and the head 11 is attracted to the support portion 4'.

Figure 7 is a cross-sectional view of the fastening tool 1' after the head 11 of the cleavage bolt 10 has been cut off. When the fastening tool 1' is further rotated by the tool after the cleavage bolt 10 is fastened, the force attempting to rotate the head 11 relative to the constricting portion 12 and the threaded portion 13 causes the cleavage bolt 10 to break at the boundary between the head 11 and the constricting portion 12. As a result, as shown in Figure 7, the head 11 is separated from the remaining portion of the cleavage bolt 10 (the constricting portion 12 and the threaded portion 13) fixed to the member, and remains as a fragment in the fastening portion 2'. In other words, the head 11 is cut off from the cleavage bolt 10.

In this embodiment, since the support portion 4' is configured as a magnet, the head portion 11 is held by the magnet at the fastening portion 2'. Therefore, even when the fastening tool 1' is held so that the fastening portion 2' is positioned vertically downward, it is possible to prevent the head portion 11, severed from the cutting bolt 10, from falling onto the member fastened by the cutting bolt 10.

The connecting portion 8 is fixed to the support portion 4' and the tool mounting portion 7', connecting the support portion 4' and the tool mounting portion 7'. The movement restricting portion 9 has a cylindrical shape and extends outward from the connecting portion 8 in the short direction (radial direction) of the fastening tool 1'. In this embodiment, the covering portion 3' is slidable in the longitudinal direction of the fastening tool 1', and a groove 31' is formed in the covering portion 3' that defines the range of motion of the covering portion 3'. The movement restricting portion 9 is positioned in the groove 31 of the covering portion 3' and abuts against the end of the groove 31 to restrict the movement of the covering portion 3'.

The spring 6' is positioned inside the covering portion 3' around the support portion 4'. One end of the spring 6' abuts against the inner wall of the covering portion 3', and the other end abuts against the connecting portion 8. The spring 6' expands and contracts between the connecting portion 8 and the covering portion 3 in the longitudinal direction of the fastening tool 1'.

The covering portion 3' moves linearly between a proximal position close to the clamping portion 2' and a distal position far from the clamping portion 2' in the longitudinal direction of the fastening tool 1'. As shown in Figures 5 to 7, when no force is applied to the covering portion 3', the biasing force of the spring 6' positions the covering portion 3' at the proximal position. When the covering portion 3' is at the proximal position, the proximal end of the support portion 4' is separated distally from the proximal end of the covering portion 3', and a recess of the clamping portion 2' is formed on the proximal side of the support portion 4'.

On the other hand, when force is applied distally to the covering portion 3' by the operator, the spring 6' is compressed by the covering portion 3'. As a result, the covering portion 3' moves from the proximal position to the distal position. Figure 8 is a cross-sectional view of the fastening tool 1' when the covering portion 3' has moved to the distal position. When the covering portion 3' moves to the distal position, the head 11 held by the support portion 4' is exposed to the outside of the covering portion 3'. In other words, in this embodiment, the covering portion 3' functions as an exposed portion that exposes the head 11 remaining in the fastening portion 2' due to the breakage of the neck-cutting bolt 10 to the outside of the covering portion 3'.

The head 11, exposed to the outside of the covering portion 3', is detached from the support portion 4' by the worker and collected in a recovery container or the like. For example, the worker holds the covering portion 3' distally with one hand and detaches the head 11 from the support portion 4' with the other hand. Therefore, according to this embodiment, the head 11 of the neck-cutting bolt 10 can be removed from the fastening tool 1' without using any device other than the fastening tool 1'. This reduces the cost and occupied space of production equipment and increases production efficiency. Furthermore, in this embodiment, since the covering portion 3' functions as an exposed portion, the head 11 of the neck-cutting bolt 10 can be removed from the fastening tool 1' without adding a part like the sliding portion 5 in the first embodiment.

After the head 11 is removed from the fastening tool 1', the worker releases their hand from the covered portion 3'. As a result, the spring 6' biases the covered portion 3' proximal, causing it to move from the distal position to the proximal position. Therefore, the covered portion 3' can be automatically returned to its initial position (proximal position), allowing for quick commencement of work on the next neck-cutting bolt 10 using the fastening tool 1'.

<Third Embodiment>
The configuration and operation of the fastening tool according to the third embodiment are basically the same as those of the fastening tool according to the first embodiment, except for the points described below. Therefore, the third embodiment of the present invention will be described below focusing on the differences from the first embodiment.

Figure 9 shows a fastening tool 1" according to the third embodiment of the present invention. Figure 9(a) shows the fastening tool 1" when the support portion 4" and the sliding portion 5" are in the distal position, and Figure 9(b) shows the fastening tool 1" when the support portion 4" and the sliding portion 5" are in the proximal position.

In the third embodiment, the support portion 4" is made of a non-magnetic material, and the fastening tool 1" further includes a magnet 20. The magnet 20 is provided inside the covering portion 3" and positioned between the covering portion 3" and the support portion 4". The magnet 20 is positioned distal to the fastening portion 2" so as to be adjacent to the fastening portion 2" in the longitudinal direction (axial direction) of the fastening tool 1". The magnet 20 is fixed to the covering portion 3", and the support portion 4" and the sliding portion 5" move relative to the covering portion 3" and the magnet 20 in the longitudinal direction of the fastening tool 1". Note that the support portion 4" and the sliding portion 5" may be integrally molded.

The magnet 20 possesses magnetic force and is configured, for example, as a permanent magnet. The magnet 20 has a cylindrical shape or is configured as a plurality of rectangular parallelepiped magnets (for example, two or four). When the head 11 of the shank bolt 10 is positioned on the tightening portion 2", the magnet 20 attracts the head 11 by magnetic force, and the head 11 is attracted to the magnet 20. Therefore, as shown in Figure 9(a), when the head 11 is cut off from the shank bolt 10, the magnet 20 holds the head 11 in the tightening portion 2". Thus, even if the fastening tool 1" is held so that the tightening portion 2" is positioned vertically downward, it is possible to prevent the cut head 11 from falling onto the member fastened by the shank bolt 10. Note that in Figure 9(a), the support portion 4" is spaced apart from the head 11, but when the support portion 4" and the sliding portion 5" are in a distal position, the support portion 4" may be in contact with the head 11.

In fastening tool 1", similar to fastening tool 1, the support portion 4" and the sliding portion 5" press against the head 11 of the cleavage bolt 10 through a sliding motion. As a result, the head 11 moves proximal to the support portion 4" and is pushed out of the covering portion 3". At this time, the head 11 is separated from the magnet 20 and detaches naturally from fastening tool 1" without the need for human intervention. Therefore, according to the fastening tool 1" of the third embodiment, the process of removing the severed head 11 from the cleavage bolt 10 from fastening tool 1" can be made easier.

<Other Embodiments>
Although preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes can be made within the scope of the claims. For example, only the proximal ends of the support portions 4 and 4' may be configured as magnets.

Furthermore, when the head-cutting bolt 10 is fastened with the fastening tools 1 and 1' held horizontally, the support parts 4 and 4' may be made of a non-magnetic material. In this case, the head 11 severed from the head-cutting bolt 10 is supported by the covering parts 3 and 3', and falls into the collection container by gravity when exposed from the covering parts 3 and 3'. In this case, the support part 4 and the sliding part 5, or the support part 4' and the connecting part 8, may be integrally molded.

Furthermore, springs 6, 6', and 6'' may be omitted from fastening tools 1, 1', and 1'', allowing the operator to return the exposed parts to their initial positions.

Furthermore, the embodiments described above can be implemented in any combination. For example, in the fastening tool 1' shown in Figure 5, similar to the fastening tool 1'', the support portion 4' may be made of a non-magnetic material, and the fastening tool 1' may include a magnet 20 positioned between the covering portion 3' and the support portion 4'.

1, 1', 1" Fastening tool 2, 2', 2" Tightening part 3, 3', 3" Covering part 4, 4', 4" Support part 5, 5" Sliding part 10 Cutting bolt 11 Head

Claims (5)

A fastening tool used for fastening neck bolts,
A tightening part that engages with the head of the aforementioned cutting bolt and applies tightening torque to the cutting bolt,
A covering portion that covers the aforementioned fastening portion,
The system includes an exposed portion which exposes the head of the bolt remaining in the fastening portion due to the fracture of the head-cutting bolt to the outside of the covering portion,
The exposed portion is slidable in the longitudinal direction of the fastening tool by force applied by an operator , and the sliding motion exposes the head to the outside of the covered portion of the fastening tool. The fastening tool according to claim 1, wherein the head is held by a magnet at the fastening portion when exposed to the outside of the covering portion . The fastening tool according to claim 1 or 2, wherein the exposed portion presses against the head by a sliding motion. The fastening tool according to claim 1 or 2, wherein the covering portion functions as the exposed portion by linearly moving in the longitudinal direction between a proximal position close to the fastening portion and a distal position far from the fastening portion due to the force . The fastening tool according to claim 1 or 2, further comprising a spring for biasing the exposed portion.