JP2000220621A - Screwing tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uniformize the fastening force by integrally connecting a screw member to be screwed to a screw bore with an operating member for rotating it, and breaking the connection part at a prescribed rotating torque to separate both the members. SOLUTION: A screwing tool 6 comprises a screw member 8, an operating member 10 for rotating it, and a minor diameter connection part 12 for integrally connecting the both. The screw member 8 is formed of a shank 14 and a hexagonal head 16, and the operating member 10 is formed of a cylindrical shaft 18 and a small diameter cylindrical lever 20. The lever 20 is fixed to an insert hole 18a by soldering. When the operating member 10 is rotated to screw the screw member 8 into a screw bore 2b, the connection part 12 is broken when the rotating torque reaches a prescribed value, and the screw member 8 is separated from the operating member 10. The screw member 8 is left in the state where a cover 4 is fixed to a frame 2 as in the past, and the operating member 10 is disposed. According to this, the fastening force can be uniformized at a low cost to prevent the looseness, and a work can be easily and quickly performed since the screw member and the operating member are integrated together before use.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screw fastener used for fastening a plurality of members.

[0002]

2. Description of the Related Art For example, when two members are fastened, a screw hole is formed in both members, or a screw hole is formed only in a member on the back side in the screw traveling direction and a member on the near side is formed. A screw insertion hole is simply formed, and a screw (a screw fastener) is screwed into the screw hole with a rotary operation tool such as a screwdriver to fasten the screw. Generally, a screw is composed of, for example, a screw shaft having a screw thread formed in a helical shape and a head integrally formed with the screw shaft. Etc. A wrench or the like is also used as a rotary operation tool, and correspondingly, the head of the screw is formed in a hexagonal shape, for example, or has a hexagonal concave portion.

[0003]

As described above, when fastening between members with screws or the like, a rotary operation tool such as a screwdriver for turning the screws is required in addition to the screws. There was a problem that both preparations were troublesome. Since a screw and a rotary operation tool such as a screwdriver corresponding to the screw are not always distributed as a set, it is troublesome to prepare a rotary operation tool according to the screw to be used. If the hand-held rotary operation tool does not fit the screws used, it must be procured separately. Rotary operation tools such as a screwdriver are frequently and versatilely used, so that the storage location is easily disturbed and often cannot be dealt with promptly.

[0004] When a screwing operation is performed in a factory or the like, the above-mentioned problems do not often occur because the arrangement and number of tools are maintained. When it becomes necessary, the trouble and inconvenience become remarkable.

[0005] In addition, in the screwing operation, in addition to the above-mentioned workability problems, there is a problem that the screw tightening force (operating force or rotational torque by the rotation operation tool) cannot be made uniform. There is no problem if the screw diameter is relatively large and the breaking strength of the screw or screw hole with respect to the tightening force is high. , So-called screw breakage easily occurs. For example, when a metal member is fastened with a small-diameter plastic screw, if the rotation torque is too large, the screw thread is likely to be crushed. Conversely, when the plastic member is fastened with a metal screw, the screw torque is too large. Holes are easily crushed. When the screw is crushed, it is easy to replace it. However, when the screw hole on the member side is crushed, the equipment cannot be used or the commercial value is reduced, which may cause a large economic burden.

[0006] The use of a pneumatic tool or a hydraulic tool, a torque gauge, a torque limiter, or the like capable of keeping the tightening force constant can solve the problem caused by the unevenness of the tightening force, but the equipment cost is high.

SUMMARY OF THE INVENTION Accordingly, it is a main object of the present invention to provide a screw fastener capable of solving the above-mentioned problems in workability and problems relating to tightening force at low cost.

[0008]

According to the present invention, in order to achieve the above object, a screw and a rotary operation tool corresponding thereto are integrally distributed, and the rotary operation tool is basically provided. It is positioned as a consumable that is used only for one fastening operation. Thereby, it is possible to adopt a configuration in which the rotational torque and the separating force between the two correspond.

More specifically, according to the first aspect of the present invention, the screw member screwed into the screw hole and the operating member for turning the screw member are integrally connected, and the connecting portion is formed by a predetermined rotational torque. , The screw member and the operation member are separated from each other.

According to a second aspect of the present invention, in the configuration of the first aspect, the connecting portion is formed in a shaft shape, and a sectional area of the connecting portion on the screw member side is small.

According to a third aspect of the present invention, in the configuration of the first aspect, the connecting portion is formed in a tapered shape whose diameter decreases toward the screw member.

According to a fourth aspect of the present invention, in the configuration of the first, second or third aspect, the head of the screw member is formed to be rotatable.

According to a fifth aspect of the present invention, in the configuration of the fourth aspect, the operation member has an engaging portion that engages with the head.

According to the sixth aspect of the present invention, the first, second and third aspects of the present invention are provided.
The configuration described in 3, 4, or 5, wherein the operating member has a shaft portion extending in the axial direction of the screw member, and a lever portion extending in a radial direction of the shaft portion.

According to a seventh aspect of the present invention, in the configuration of the sixth aspect, the shaft portion and the lever portion are formed separately.
The shaft portion has an insertion hole for inserting the lever portion in a radial direction.

According to an eighth aspect of the present invention, in the configuration of the sixth aspect, the shaft portion and the lever portion are formed separately.
A configuration is adopted in which a lever housing recess for housing the lever portion is formed in the shaft portion.

According to a ninth aspect of the present invention, in the configuration of the sixth aspect, the shaft portion and the lever portion are formed separately.
The lever portion has a configuration in which one end thereof is rotatably connected to the shaft portion and is provided so as to be foldable.

According to a tenth aspect of the present invention, in the configuration of the seventh aspect, a configuration is adopted in which a holder for holding the shaft portion and the lever portion substantially in parallel is provided.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. An example is shown in which a cover 4 that covers the back opening 2a of the frame 2 of the device is screwed. A screw hole 2b is formed in the frame 2, and an insertion hole 4a having a diameter slightly larger than the screw hole 2b is formed in the cover 4. ing. The screw fastener 6 in the present embodiment includes a screw member 8, an operation member 10 for turning the screw member 8, the screw member 8 and the operation member 10.
Are connected to each other at a small diameter. The screw member 8 has a screw shaft 14 screwed into the screw hole 2b, and a hexagonal head 16 integrally formed on the operation member 10 side of the screw shaft 14. The operating member 10 has a cylindrical shaft portion 18 extending in the axial direction of the screw shaft 14, and a small-diameter cylindrical lever portion 20 extending in the radial direction of the shaft portion 18.
As shown in FIG. 2, an insertion hole 18a penetrating in the radial direction is formed in the shaft portion 18, and the lever portion 20 is fixed to the lever portion 20 by a method such as soldering after being inserted into the insertion hole 18a. . Therefore, the screw fastener 6 flows in an integrated shape as shown in FIG.

The size of the diameter of the connecting portion 12 is set to a size that can be broken by a predetermined rotational torque. Here, the "predetermined rotational torque" means an appropriate tightening force when the screw member 8 is screwed into the screw hole 2b and fixed. When the operation member 10 is rotated and the screw member 8 is screwed into the screw hole 2b, as shown in FIG. 3, when a predetermined rotation torque is reached, the connecting portion 12 is broken, and the screw member 8 and the operation member 10
Separates. The screw member 8 remains in a state where the cover 4 is fixed to the frame 2 in the same manner as in the conventional case where the screw member 8 is rotated and tightened with a rotary operation tool such as a screwdriver. Operation member 10
Is disposable.

Conventionally, the tightening force could not be made uniform unless expensive equipment such as a pneumatic tool was used. However, according to the screw fastener 6 according to the present embodiment, the connecting portion can be operated by anyone. Since the breakage of No. 12 is broken when a certain rotation torque is reached, the tightening force can be made uniform at low cost.
The diameter of the connecting portion 12 can be set based on experimental data corresponding to the diameter of the screw shaft 14, the type of screw, the material, or the like. The screw fastener 6 may be formed of metal by cutting or molding, or may be integrally formed by injection molding of plastic. Further, the operating member 10 and the commercially available screw member 8 may be formed by metal joining with the connecting portion 12.

In this embodiment, since the head 16 of the screw member 8 is formed in a hexagonal shape, the screw member 8 can be removed or adjusted with another tool such as a monkey wrench or a box wrench even after screwing. Is possible. Depending on the field of use, it may not be necessary to remove the screw member 8 after fastening, or there may be a demand that the screw member 8 cannot be positively rotated after fastening. In this case, for example, FIG. As shown, a screw member 8 having a circular simple convex head 22 may be employed.

FIG. 5 shows a modification of the connecting portion 12. As shown in FIG. The same parts as those in the above embodiment are denoted by the same reference numerals,
Unless otherwise required, the description already given is omitted (the same applies to other embodiments described below). Connecting part 2 in the present embodiment
4 has a circular cross section in a direction substantially perpendicular to the axial direction,
That is, it is formed in a columnar shape, and the cross-sectional area on the screw member 8 side is set smaller than the others by chamfering. Therefore, when a predetermined rotational torque is reached, breakage occurs at the portion 24a having a small cross-sectional area. By changing the cross-sectional area in this way, the breaking position can be set arbitrarily. In the case where there is a member that hinders the fastening operation in front of the fastening site and the depth to the fastening site is large, conventionally, a method has been adopted in which the screw is entered with the screw held by the driver with magnetic force. However, in the case of the present embodiment, the same can be achieved by making the connecting portion 24 long, and the screw member 8
And the connecting portion 24 are firmly fixed, so that even if the connecting portion 24 strikes a member on the way, there is no fear that the posture of the screw is shifted or dropped as in the case of magnetic force holding.

FIG. 6 shows a modification of the connecting portion 12. As shown in FIG. The connecting portion 26 in the present embodiment is formed in a conical shape in which the diameter decreases toward the screw member 8 side, that is, in a tapered shape. When a predetermined rotational torque is reached, the conical top portion 26a is broken. The connection portions 12, 24, and 26 are all broken because of a small cross-sectional area. For example, the diameter of the connection portion 24 in FIG. The strength may be weakened by chemical treatment, heat treatment, radiation irradiation, or the like, so that destruction occurs at the site.

FIG. 7 shows a modification of the operation member 10. As shown in FIG. The operating member 28 in the present embodiment includes a columnar shaft portion 30 and a columnar lever portion 32 having a diameter larger than the shaft portion 30 and having an outer surface subjected to anti-slip processing such as knurling. FIG. 8 shows another modification of the operation member 10. The operation member 34 in the present embodiment includes a cylindrical shaft 36 and a disk-shaped lever 38.

The operating members 10 and 2 in each of the above embodiments.
8, 34 have the same shape during distribution (when not in use) and during use, but the following shows an example in which the shape during distribution can be made compact. In the embodiment shown in FIG.
Is not fixed to the insertion hole 18a, and can be freely inserted and removed. The shaft 18 has a plastic holder 40.
Is fixed, and the lever portion 20 is held by the holding portion 40a of the holder 40 with an elastic force when the screw fastener 6 is not used, as shown by a two-dot chain line. Holder 40a when used
Then, the lever 20 is removed and inserted into the insertion hole 18a. According to this embodiment, bulkiness during distribution can be reduced, and
The holding and management of the holder 40 is facilitated.

FIG. 10 shows a modification in which the shape at the time of distribution can be made compact. The operation member 42 in the present embodiment includes a cylindrical shaft portion 44 and a prismatic lever portion 48 having one end connected to the shaft portion 44 by a pin 46. The shaft portion 44 is formed with a lever accommodating recess 50 capable of accommodating the lever portion 48 in an embedded state, and the lever portion 48 is freely foldable. At the time of circulation, the lever portion 48 is accommodated in the lever accommodating recess 50, and is pulled out so as to be rotatable when used. The shaft portion 44 and the lever portion 48 may not be connected, and the lever portion 48 may be simply housed in the lever housing recess 50.

FIG. 11 shows still another modification of the operation member 10. Operation member 52 in the present embodiment
Is formed in a columnar and L-shape, and the screw member 8
A hexagonal concave portion 52a as an engaging portion that engages with the head 16 of the screw member 8 is formed at the end opposite to the side. Therefore, after the fastening due to the destruction of the connecting portion 12, the operation member 52 can be used as a rotation operation tool for removing the screw member 8.

FIGS. 12 and 13 show a modification of the type in which the operating member is used as a rotary operating tool. The head 54 of the screw member 8 in the present embodiment is formed in a circular shape, and has a pair of concave portions 54a, 54a facing in the radial direction as shown in FIG. As shown in FIG. 12, a pair of protrusions 56 a as engagement portions that engage with the recesses 54 a, 54 a of the head 54 of the screw member 8 are provided at the end of the operation member 56 opposite to the screw member 8 side. , 56a are formed. Therefore, after the fastening by the destruction of the connecting portion 12, the operation member 56 can be used as a rotation operation tool for removing the screw member 8. The configuration as a rotary operation tool for removing the screw member 8 can be similarly implemented with the operation member in each of the above embodiments.

In each of the above embodiments, the shape of the shaft 18 of the operating member 10 is circular in cross section.
Various shapes such as a square shape can be adopted. Further, the screw member 8 has a shape only for fastening the cover 4, that is, a conventional set screw shape. However, the head 16 of the screw member 8 has, for example, a long columnar or prismatic shape. The portion may be used as a locking member for locking another member.

[0031]

According to the present invention, the tightening force can be made uniform with a low-cost structure, and screw breakage due to excessive tightening force or loosening due to insufficient tightening force can be prevented. Further, since the screw member and the operating member are circulated integrally until they are used, the screwing operation can be performed easily and quickly.

[Brief description of the drawings]

FIG. 1 is a schematic side view of a screw fastener according to one embodiment of the present invention.

FIG. 2 is a perspective view of a state where a lever portion is separated.

FIG. 3 is a schematic side view showing a state in which a screw member and an operation member are separated due to breakage of a connecting portion.

FIG. 4 is a schematic side view showing a state in which the screw member and the operating member are separated due to the destruction of the connecting portion in the type in which the screw member cannot be removed after fastening.

FIG. 5 is a main part side view showing a modified example of the connecting portion.

FIG. 6 is a side view of a main part showing a modification of the connecting part.

FIG. 7 is a perspective view showing a modification of the operation member.

FIG. 8 is a perspective view showing a modification of the operation member.

FIG. 9 is a perspective view showing a modification of the operation member.

FIG. 10 is a perspective view showing a modification of the operation member.

FIG. 11 is a perspective view of an example in which the operation member can rotate the screw member after fastening.

FIG. 12 is a perspective view of an example in which the operating member can rotate the screw member after fastening.

FIG. 13 is a perspective view of the screw member of the example shown in FIG.

[Explanation of symbols]

 2b Screw hole 8 Screw member 10 Operating member 12, 24, 26 Connecting part 16, 22, 54 Head 18 Shaft part 18a Insertion hole 20 Lever part 40 Holder 50 Lever accommodation concave part 52a, 56a Engaging part

Claims (10)

[Claims] A screw member screwed into a screw hole and an operation member for turning the screw member are integrally connected, and the screw member and the operation member are separated by a breakage of a connection portion by a predetermined rotation torque. A screw fastener characterized by being separated. 2. The screw fastener according to claim 1, wherein the connecting portion is formed in a shaft shape, and a cross-sectional area of the connecting portion on the screw member side is small. 3. The screw fastener according to claim 1, wherein said connecting portion is formed in a tapered shape whose diameter decreases toward said screw member. 4. The screw fastener according to claim 1, wherein the head of said screw member is formed so as to be rotatable. 5. The screw fastener according to claim 4, wherein said operating member has an engaging portion for engaging said head. 6. The screw fastener according to claim 1, wherein said operating member has a shaft portion extending in an axial direction of said screw member, and a lever portion extending in a radial direction of said shaft portion. A screw fastener characterized by having: 7. The screw fastener according to claim 6, wherein the shaft portion and the lever portion are formed separately, and an insertion hole for inserting the lever portion in a radial direction is formed in the shaft portion. A screw fastener. 8. The screw fastener according to claim 6, wherein the shaft portion and the lever portion are formed separately, and a lever housing recess for housing the lever portion is formed in the shaft portion. Screw fastener. 9. A screw fastener according to claim 6, wherein said shaft portion and said lever portion are formed separately, and said lever portion is connected at one end thereof to said shaft portion so as to be freely foldable. A screw fastener characterized by being made. 10. The screw fastener according to claim 7, further comprising a holder for holding the shaft portion and the lever portion substantially in parallel.