JP2007278476A - Fastening torque adjusting method and mechanism for bolt fastening part - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To appropriately adjust the fastening torque of a bolt fastening part. <P>SOLUTION: An adjusting method is provided for adjusting the fastening torque of a thread fastening mechanism for engaging an engaging part comprising a bolt head 8 or a nut 7, with a fastening tool to perform turning operation. In the turning position where the engaging part is fastened by the predetermined fastening torque, the engagement of the fastening tool with the engaging part is released by a regulating part located on the outer periphery of the engaging part on the fastened object side or the fastening tool tip side, to inhibit further fastening. The regulating part is a cylindrical collar part 13 protrusively provided at the outer end of a spacer 12 loosely fitted to a thread part 9 on the fastened object side of the engaging part, holding the engaging part in the fastening state and abutting on the tip face of the fastening tool to release the engagement of the fastening tool, or a collar part 13 protrusively provided on the end face side of a box spanner 22, holding the engaging part in a loosely fitted state in the fastening state and allowing the tip face to abut on the fastened object side to release the engagement of the fastening tool. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method and a mechanism for adjusting a tightening torque of a bolt tightening portion for use in a hose clip or the like.

  Generally, when two or more items are stacked and tightened with bolts or nuts, an appropriate tightening force is required depending on the type, structure, size, material, etc. of the object to be tightened. For tools that use power such as an impact wrench, it is usually determined by a tightening torque that is set to a higher value, depending on the force of the operator. For this reason, there is no particular problem when the tightening force of the tightening portion corresponds to the set tightening torque of the impact wrench, but in other cases, excessive or insufficient tightening force occurs.

Of these, for example, for air conditioners for automobiles and rubber hose clips for air supply / exhaust systems, for objects that require durability of the hose connection part under severe conditions, the rubber thickness decreases due to deterioration due to aging of rubber, etc. Attempts have been made to compensate for changes in tightening force due to deterioration by elastic tightening force (see Patent Documents 1 and 2).
Japanese Patent Publication No. 7-26712 Japanese Utility Model Publication No.7-1395

  However, since the normal impact wrench used for the above tightening is used for many objects, the tightening torque adjustment is set to a high torque. When tightened with a wrench, the tightening force is too strong and the hose or hose clip is overloaded, leading to problems such as deteriorating the hose or impairing the durability of the clip. On the other hand, when the tightening force is insufficient due to insufficient tightening torque, there is a disadvantage that the function of the hose clip is insufficient. The present invention proposes an adjustment method and mechanism suitable not only for adjusting the tightening torque of the hose clip but also for tightening adjustment which generally requires more strict tightening torque management.

  In order to solve the above-mentioned problems, the present invention is an adjustment method for adjusting a tightening torque of a screwing mechanism that is first rotated by engaging an engaging portion including a bolt head 8 or a nut 7 with a tightening tool. The engagement of the tightening tool with the engagement portion at the rotational position where the engagement portion is tightened with a predetermined tightening torque is applied to the outer periphery of the engagement portion on the tightening object side or the tightening tool tip side. It is characterized in that it is released by the positioned restricting portion and further tightening is impossible.

  Secondly, a spacer 12 is loosely fitted on the threaded portion 9 of the engagement portion on the tightening object side, and is projected from the outer end portion of the spacer 12 to receive and tighten the engagement portion in a tightened state. The cylindrical collar portion 13 that comes into contact with the tip surface of the attachment tool and releases the engagement of the tightening tool is used as a restriction portion.

  Thirdly, a box spanner 22 is used as a tightening tool, protrudes on the end surface side of the box spanner 22, accommodates the engaging portion in a loosely fit state in the tightened state, and tightens the end surface. The collar portion 13 that is brought into contact with the side and releases the engagement of the tightening tool is used as a restricting portion.

  Fourth, the tightening tool body is an impact wrench 21.

  Fifth, a mechanism for adjusting the tightening torque of a screwing mechanism for rotating the engagement object by engaging an engagement portion composed of a bolt head 8 or a nut 7 with a tightening tool. A restricting member for releasing the engagement of the tightening tool with respect to the engaging portion is provided at the outer peripheral position of the engaging portion at a rotation position where the engaging portion is tightened with a predetermined torque.

  Sixth, the restriction member is externally mounted around the axis of the bolt 3 in the tightened state of the engaging portion and accommodates the engaging portion itself so as to come into contact with the tip of the tightening tool at the time of tightening so as to release the engagement. It is characterized by comprising a spacer 12 provided with a portion 13.

  Seventh, the spacer 12 accommodates the bolt head 8 and has a restricting portion formed by a cylindrical collar portion 13 having an open end, and an insertion hole 16a through which the bolt 3 is loosely fitted from within the restricting portion. It is characterized by comprising the bottom 14 formed.

  Eighth, it is characterized in that a boss portion 16 having an insertion hole 16a extending on the base end side of the bottom portion 14 is provided.

  Ninth, the object to be tightened is an elastic member that is resiliently tightened.

  Tenth, the object to be tightened is a hose clip 1 whose inner diameter is reduced and enlarged by a tightening bolt 3 attached to the outer peripheral side of a tightening ring 2 formed in a ring shape.

  Eleventh, the hose clip 1 has the end of the tightening ring 2 intersecting and protrudes to the outer peripheral side, and the screw receiver 4 that rotatably receives and supports the tip of the bolt 3 is opposed to the screw receiver 4. And a nut stopper 6 for supporting the nut 7, and a spacer 12 is loosely fitted between the nut 7 of the bolt 3 screwed into the nut 7 and the bolt head 8.

  Twelfth, the hose clip 1 is characterized by comprising an elastic member that elastically tightens the outer periphery of the hose.

  According to the present invention configured as described above, the tightening portion for tightening and fixing the engaging portion including the bolt head and the nut is fastened to a nut driver (box spanner), an impact wrench, or the like. When tightening with a tool, the tool is automatically disengaged from the engaging portion at the rotational position where a predetermined tightening torque is reached, so that an appropriate tightening force can be obtained and more Since tightening is impossible, there is an advantage that damage to the tightening object due to overloading of tightening, deterioration of function, and other problems are prevented.

The embodiment of the present invention shown below will be described with reference to an example of a hose clip.
A hose clip 1 which is an object to be tightened shown in FIG. 1 includes a tightening ring 2 for tightening the hose, a bolt 3 for tightening the tightening ring 2, and a restriction for restricting overtightening of the bolt. And a member.

  The tightening ring 2 is made of an elastic member such as a steel wire, is bent into a ring shape, and is formed so as to protrude to the outer peripheral side after both ends intersect. A screw receiver 4 bent in a U-shape in a side view for receiving and supporting the bolt 3 rotatably is provided on one end side of the end portion of the tightening ring 2, and the screw receiver 4 is opposed to the other end side. A nut stopper 6 that supports the nut 7 is provided. This nut stopper 6 is formed by bending both ends of the steel wire into a U shape when viewed from the front, and the bent ends are inserted into two locking holes 7a and 7a formed in front and rear of the plate-like nut 7. The nut 7 is locked and held.

  The bolt 3 includes a hexagonal bolt head 8, a screw portion 9, and a holding pin 11 at the tip of the screw portion. The holding pin 11 is rotatably supported by a screw receiver 4 via a washer 17. The bolt head 8 is provided with a locking hole 8 a for inserting a Phillips screwdriver, and the screw portion 9 is screwed into the screw hole of the nut 7. The locking hole 8a can be used when the bolt 3 is tightened with a screwdriver type tool, and in the embodiment shown in FIGS. 1 to 5, it is necessary to be sure to use a screwdriver type tool to loosen the bolt. ing.

  The sleeve-like spacer 12 inserted between the nut 7 and the bolt head 8 with the bolt 3 inserted into the nut 7 is a cylindrical collar portion that accommodates the bolt head 8 of the bolt 3 in the bolt-tightened state. (Regulatory part) 13, bottom part 14 in which an insertion hole 16 a is inserted from the inside of the collar part 13 in a loosely fitted state, and a boss part 16 in which an insertion hole 16 a is formed to extend on the base end side of the bottom part 14 It consists of and. The diameter of the cylinder of the collar portion 13 is determined by the size of the bolt head 8, and the length from the open end of the collar portion 13 to the inner bottom surface of the bottom portion 14 is a depth that can be accommodated by the bolt head 8 (disengaged at a set tightening torque or more). The depth from the bottom surface of the bottom portion 14 to the base end surface of the boss portion 16 is determined by the set value of the tightening force (tightening torque) of the object to be tightened.

Next, a method for adjusting the tightening torque when the object to be tightened is tightened using the hose clip 1 will be described.
As shown in FIG. 3, the hose 19 is fitted to the outer periphery of the end portion of the pipe 18, the fastening ring 2 of the hose clip 1 is externally attached to the outer periphery of the hose 19, and the bolt 3 is attached to the collar 13 side of the spacer 12. Then, the nut 7 is screwed onto the tip of the bolt 3, and the holding pin 11 at the tip of the bolt 3 is inserted and supported by the screw receiver 4 in a resilient and elastically inserted state via a washer 17. .

  By rotating the bolt 3 forward, the nut stopper 6 and the nut 7 are pushed open, and the inner diameter of the tightening ring 2 is reduced to tighten the hose. On the contrary, when the bolt 3 is rotated in the reverse direction, the screw receiver 4 and the nut stopper 6 are expanded by the elastic restoring force of the tightening ring 2 so that the inner diameter of the tightening ring 2 is increased and the tightening force of the hose is loosened. It is done.

  FIG. 4 shows a state in which the bolt 3 is tightened by engaging the bolt head 8 with a box spanner (nut driver) 22 of an impact wrench 21 which is a tightening tool. By rotating the bolt 3 in the tightening direction by the impact wrench 21, the bolt 3 spreads the screw receiver 4 and the nut 7, while the bolt head 8 is generally accommodated, the engagement accommodating portion 22 a of the box spanner 22. When the bolt head 8 is pulled out and disengaged, the engagement between the two is released, and the bolt 3 cannot be tightened any further. This engagement is released because the bolt head 8 is inserted into the collar portion 13 by forward rotation of the bolt, but the tip of the box spanner 22 comes into contact with the end face of the collar portion 13 and stops.

  If each member of the hose clip 1 is designed so that an appropriate tightening force according to the purpose can be obtained at the rotation position of the bolt 3 which has become impossible to tighten, a high torque impact wrench 21 can be used. Even in such a case, it is possible to prevent the occurrence of various inconveniences due to damage to the tightening object due to overtightening or insufficient tightening. In addition, when a tightening object such as a hose is formed of an elastic member, an appropriate tightening force can be obtained over a long period of time by finely adjusting the elastic tightening force. Further, loosening of the tightening portion can be prevented also by using the hose clip 1 for tightening the hose 19 as an elastic member.

  In the above example, the bolt head 3 is engaged with the box spanner 22 of the impact wrench 21, but even if the manual box spanner 22 is used, the effect of preventing overtightening or insufficient tightening can be expected.

  Further, in the above example, the collar portion 13 which is a restricting portion is provided on the spacer 12, but by projecting directly on the end face of the nut 7 on the bolt head side as shown in FIG. Can be made. In this case, the sleeve-like spacer 12 is unnecessary.

  In addition, in the tightening torque adjusting method of the present invention, as shown in the above, the collar portion in which the bolt head 8 is loosely fitted to the peripheral edge of the opening end of the bolt head engaging accommodating portion 22a of the box spanner 22 as a tightening tool. What extended 13 can be used. In this case, when the bolt 3 is continuously rotated in the tightening direction while the end surface of the collar portion 13 is in contact with the surface on the object to be tightened, the bolt head 8 comes out of the collar portion 13 and the engagement between the two. This is a failure, and further tightening is restricted. In this tightening method, there is no need for a spacer for releasing the engagement between the tool and the bolt head 8 at a tightening rotation position exceeding a certain tightening force.

  In the above embodiment, the case where the fastening tool is engaged with the bolt head 8 has been described. For example, a box spanner-type fastener is fitted with a hexagonal nut or the like in addition to the bolt head. Therefore, the engagement target of the fastener includes a nut other than a bolt head. Therefore, the nut also becomes an engaging portion for engaging the tightening tool together with the bolt head.

It is a disassembled perspective view showing the tightening torque adjusting mechanism of the present invention. It is a front sectional view showing the tightening state of the tightening torque adjusting mechanism. It is an expanded surface sectional view of the control member used for a tightening torque adjustment mechanism. It is a top view in the case of tightening operation of a tightening torque adjustment mechanism with an impact wrench. It is front sectional drawing showing the example of components of other embodiment of the clamping torque adjustment mechanism of a clamping part. It is front sectional drawing showing the example of the tool in the case of implementing the fastening torque adjustment method of a fastening part with a special tool.

Explanation of symbols

1 Hose clip (object to be tightened)
2 Tightening ring 3 Bolt 4 Screw receiver 6 Nut stopper 7 Nut 8 Bolt head 9 Screw part 11 Holding pin 12 Spacer (regulating member)
13 Color part (Regulation part)
14 Bottom 16 Boss 17 Washer 18 Pipe 19 Hose (Object to be tightened)
21 Impact wrench 22 Box spanner (nut driver)
22a Bolt head (nut) engagement receiving portion 23 Chuck

Claims (12)

  An adjustment method for adjusting a tightening torque of a screwing mechanism that engages a tightening tool and engages an engaging portion composed of a bolt head (8) or a nut (7) with the engaging portion being a predetermined The engagement of the tightening tool with respect to the engaging portion at the rotational position tightened with the tightening torque is released by the restricting portion positioned on the outer periphery of the engaging portion on the tightening object side or the tightening tool tip side, A method for adjusting the tightening torque of the bolt tightening part that makes it impossible to tighten any further.   The spacer (12) is loosely fitted on the threaded portion (9) on the tightening object side of the engaging portion, and is projected from the outer end portion of the spacer (12), and accommodates the engaging portion in the tightened state. 2. The method of adjusting a tightening torque of a bolt tightening portion according to claim 1, wherein a cylindrical collar portion (13) that comes into contact with a tip surface of the tightening tool to release the engagement of the tightening tool is used as a restricting portion.   A box spanner (22) is used as a tightening tool. The box spanner (22) protrudes from the end surface side, and in the tightened state, the engaging portion is accommodated in a loosely fitted state, and the distal end surface is an object to be tightened. The method of adjusting a tightening torque of a bolt tightening portion according to claim 1, wherein the restricting portion is a collar portion (13) that is brought into contact with the side and releases the engagement of the tightening tool.   4. The method of adjusting a tightening torque of a bolt tightening portion according to claim 1, wherein the tightening tool body is an impact wrench (21).   A mechanism for adjusting a tightening torque of a screwing mechanism for rotating an engagement object, which is a bolt head (8) or a nut (7), by engaging a tightening object with a tightening tool. A tightening torque adjusting mechanism for a bolt tightening portion in which a restricting member for releasing the engagement of the tightening tool with respect to the engaging portion is provided at the outer peripheral position of the engaging portion at a rotational position where the engaging portion is tightened with a predetermined torque. .   A restricting part (a restricting part) that is externally mounted around the axis of the bolt (3) in a tightened state of the engaging part and that receives the engaging part itself and abuts against the tip of the tightening tool during tightening. The bolt tightening torque adjusting mechanism according to claim 5, comprising a spacer (13) provided with 13).   The spacer (12) accommodates the bolt head (8), and the bolt (3) is inserted in a loosely-fitted state from the restricting portion including the cylindrical collar portion (13) having an open end. The bolt tightening torque adjusting mechanism according to claim 6, comprising a bottom (14) having an insertion hole (16a).   The tightening torque adjusting mechanism for a bolt tightening portion according to claim 7, comprising a boss portion (16) having an insertion hole (16a) extending on the base end side of the bottom portion (14).   9. The tightening torque adjusting mechanism for a bolt tightening portion according to claim 5, wherein the tightening object is an elastic member that is elastically tightened.   7. A hose clip (1) in which an inner diameter is reduced and enlarged by a fastening bolt (3) attached to an outer peripheral side of a fastening ring (2) formed by bending the fastening object into a ring shape. , 7, 8 or 9 bolt tightening torque adjusting mechanism.   A screw receiver (4) in which a hose clip (1) crosses the end of the clamping ring (2) and protrudes to the outer peripheral side, and the tip of the bolt (3) is rotatably received and supported; and the screw receiver A nut stopper (6) for supporting the nut (7) opposite to the nut (4), between the nut (7) of the bolt (3) screwed into the nut (7) and the bolt head (8) The tightening torque adjusting mechanism for a bolt tightening portion according to claim 10, wherein a spacer (12) is loosely fitted to the bolt tightening portion.   The tightening torque adjusting mechanism for a bolt tightening portion according to claim 10 or 11, wherein the hose clip (1) is made of an elastic member that elastically tightens the outer periphery of the hose.

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