JP2018141542A - Fastening structure for detachably fastening two members - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fastening structure for detachably fastening two members which can obtain a sufficient fastening load even at a small turning operation angle, hardly causes loosening generated by vibration, and can make seat surface depression and buckling caused by erroneous assembling and an eccentric load hardly occur without causing an increase in the number of part items and the enlargement of an occupation space.SOLUTION: A fastening structure comprises a fastening bolt assembly 10 in which a multiwave spring 20 having a plurality of stages of lamination parts 21 to 24 which are tightly laminated is externally fit to and held by a bolt-type turning operation member 11 in which an engagement pin 15 is arranged, a fixed nut member 30 engaged with the engagement pin 15 is arranged on a main body housing 82 side, the bolt-type turning operation member 11 is pulled down while compressing the multiwave spring 20 by the engagement of the engagement pin 15 and the fixed nut member 30 which is generated by the insertion of the fastening bolt assembly 10 into the main body housing 82 side until the engagement pin 15 is located at a starting end part of the fixed nut member 30 via a cover 84, and by turning the fastening bolt assembly by 90°, thus fastening and fixing the cover 84 to the main body housing 82.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a fastening structure for detachably fastening two members suitable for a site where vibration is generated, and more particularly, to a fastening structure including a bolt-type rotation operation member and a multiple wave spring.

  For example, in a chain saw 80 in which a reciprocating engine is used as a power source, as shown in FIG. 9A, in order to perform maintenance and inspection of the engine, cleaning the inside, etc., the main body housing 82 that houses the engine body is used. On the other hand, it is required that the cover 84 is detachably fastened. In this chain saw 80, the fastening points are a part J1 in the vicinity of the rear handle 85, and left and right parts J2 and J3 in the vicinity of the sideways C-shaped upper handle 86. For fastening the two members of the main body housing 82 and the cover 84, Conventionally, bolts have been used. However, with bolts, it takes a lot of rotation, so it takes time, and it is easy to loosen due to vibration, it is difficult to obtain the required tightening load, and the washer is easy to sag by simply inserting a normal spring washer. There's a problem.

  Therefore, in recent years, a fastening structure as shown in FIGS. 9B and 9C has been put into practical use instead of the bolt. In this fastening structure, as shown in FIG. 9B, a large number (for example, 10) of bolt-type rotating operation members 91 each having a spiral groove 95 formed at the lower end portion by about 90 ° when viewed at the rotation angle. A bolt assembly 90 for tightening (three in this case) is prepared for the tightening bolt assembly 90 formed by extrapolating the disc springs 92 in series so that the front and back are alternately overlapped and retaining with the C-shaped ring 93. As shown in FIG. 9C, ring-shaped nut members 96 each having an engaging pin 97 that meshes with the spiral groove 95 are fixed to three locations (J1, J2, J3) on the housing 82 side. (Insert molding or the like). In this case, the spiral groove 95 and the engaging pin 97 serve as a male screw and a female screw.

  In such a fastening structure, it is only necessary to rotate the bolt-type rotation operation member 91 by about 90 °. Therefore, the cover 84 can be easily and quickly attached and a large number of disc springs 92 are used. There are advantages that a required tightening load can be obtained, that the disk spring is difficult to loosen and that the disc spring is difficult to sag.

Japanese Patent No. 5038928 JP 2000-5911 A

  However, the fastening structure using the bolt-type turning operation member and the fastening bolt assembly having a number of disc springs has the following problems. In other words, the number of parts is high and the cost is high. Since it is necessary to extrapolate a large number of disc springs alternately on the front and back, misassembly is likely to occur. It is easy for the seat surface to collapse and buckle.

  Therefore, the inventors of the present invention have a strip-shaped square line in which peaks and valleys are continuously formed in a wave shape as described in Patent Documents 1 and 2 instead of a large number of disc springs. We are considering using a cylindrical multi-wave spring wound in a spiral (coiled wave spring). However, if the conventional coiled wave spring is used as it is, a small operation amount, for example, a rotation operation angle is used. When the angle is about 90 °, a sufficient spring force (clamping load) cannot be obtained, and in order to increase the load, it is necessary to increase the spring diameter and the like, and the occupied space increases. is there.

  The present invention has been made in view of the circumstances as described above. The object of the present invention is to obtain a sufficient tightening load even at a small rotation operation angle, and to prevent loosening due to vibration. An object of the present invention is to provide a fastening structure for detachably fastening two members that does not cause an increase in the number of points and occupied space, and is less likely to cause a seating surface depression or buckling due to misassembly or an unbalanced load.

  In order to achieve the above object, a fastening structure for detachably fastening two members according to the present invention is a fastening structure for detachably fastening a second member to a first member, Basically, a cylindrical multiple wave spring in which a band-like square line in which peaks and valleys are continuously formed in a wave shape is spirally wound, and a rotating engagement portion is provided at the bottom. Provided with a fastening bolt assembly that is externally held by the bolt-type rotation operation member, and a fixed engagement portion that is engaged with the rotation engagement portion is provided on the first member side. The tightening bolt assembly is rotated by a predetermined angle through the second member while being inserted into the first member side until the rotational engagement portion is positioned at the start end of the fixed engagement portion. As a result, the bolt-type rotation operation member is moved into the multiple window by the engagement between the rotation engagement portion and the fixed engagement portion. Pulled down while compressing the over blanking spring, said second member to said first member is characterized in that it is adapted to be fastened.

  Preferably, the multiple wave spring has a plurality of cylindrical laminated portions in which two or more windings are laminated in close contact with each other, and between each laminated portion adjacent in the vertical direction, a peak portion and a valley portion are provided. The portions are in contact with each other, and an eye-shaped gap including a valley portion and a mountain portion is formed between the contact portions.

  The rotation engagement portion is preferably configured by an engagement pin provided near a lower end portion of the bolt-type rotation operation member, and the fixed engagement portion is preferably engaged with the engagement pin. And a concave portion into which the engagement pin that has been guided and sent by the helical guide inclined surface is dropped.

  In a preferred aspect, the length of the engagement pin is made smaller than the outer diameter of the multiple wave spring, and the fixed engagement portion is provided with an insertion opening through which the engagement pin is inserted, and the second It has an upper surface flat part which receives the lower end part of a member.

  In a more preferred aspect, an annular convex portion is provided at a portion where the second member around the fixed engagement portion faces.

  In another preferred aspect, a step portion is provided on the outer periphery of the bolt-type rotation operation member, and a locking portion is provided on the inner periphery of the second member, and the step portion is locked to the locking portion. Until the tightening bolt assembly is inserted into the first member side through the second member until the rotating engagement portion is positioned at the start end of the fixed engagement portion. Is done.

  In a further preferred aspect, when the tightening bolt assembly is rotated, the stepped portion is disengaged from the locking portion, and the bolt-type rotating operation member is pulled down while compressing the multiple wave spring. The

  Preferably, the multiple wave springs are provided with three or more convex convex portions on the upper surface side and three convex valley portions on the lower surface side at predetermined angular intervals in the circumferential direction.

  On the other hand, a fastening bolt assembly according to the present invention is used in the fastening structure, and a band-shaped square line in which a peak portion and a valley portion are continuously formed in a wave shape is spirally wound. A multi-wave spring having a plurality of stages of a cylindrical laminated portion in which two or more windings are laminated with the entire circumference in close contact with each other, and a bolt-type rotation in which a rotation engaging portion is provided in the lower part The operation member is extrapolated and held.

  In the fastening structure for detachably fastening the two members according to the present invention, a multi-wave spring is replaced with a conventional disc spring, and particularly preferably, a laminated portion in which two or more windings are laminated in close contact with the entire circumference. Since a tightening bolt assembly is used in which multiple wave springs having a plurality of stages are externally held by a bolt-type rotation operation member, sufficient tightening is possible even with a small rotation operation angle of about 90 °, for example. A load can be obtained, and attachment / detachment work can be performed easily and quickly.

  Further, since the tightening load can be increased even with a small rotation operation angle, it is difficult to cause loosening due to vibration. Furthermore, since the multi-wave spring is a single part, the number of parts and the occupied space can be reduced, and the seat surface can be depressed or buckled due to misassembly or uneven load compared to the case where a large number of disc springs are used. It can be difficult to occur.

  Further, since it is only a single fastening bolt assembly that is separated from the two members, there are advantages in that it does not take time to attach and detach the two members and that it is difficult to lose necessary parts.

The perspective view which shows an example of the chain saw to which one Embodiment of the fastening structure for fastening the 2 member which concerns on this invention so that attachment or detachment was possible was applied. The partial expansion perspective view which shows one fastening location in the chain saw shown in FIG. The figure which is provided to description of the fastening operation using the volt | bolt type rotation operation member of this embodiment. It is a figure with which it uses for description of the fastening operation using the volt | bolt type rotation operation member of this embodiment, (A) is a partially notched XX arrow sectional drawing of FIG. 3 (A), (B) is a figure. 3 (B) is a partially cutaway XX arrow sectional view, and FIG. 3 (C) is a partially cutaway XX arrow sectional view of FIG. 3 (C). The front side perspective view which shows the bolt assembly for clamping which consists of the bolt type rotation operation member of this embodiment, a multiple wave spring, etc. FIG. The multiple wave spring of this embodiment shown by FIG. 3, FIG. 4 is shown, (A) is a top view, (B) is a perspective view. The fixed nut member which comprises the fixed engagement part of this embodiment is shown, (A) is a top view, (B) is YY arrow sectional drawing of (A), (C) was fixed to the main body housing. The upper surface side perspective view which shows a state, (D) is the lower surface side perspective view which shows the state fixed to the main body housing. The figure which shows the other example of the volt | bolt assembly for fastening of this embodiment. It is a figure used for description of the conventional fastening structure, (A) is a perspective view which shows an example of the same chain saw as FIG. 1, (B) is a figure which shows the conventional bolt assembly for fastening, (C) is a figure. The figure which shows the conventional nut member.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic perspective view showing a chain saw to which an embodiment of a fastening structure for detachably fastening two members according to the present invention is applied.

  The chain saw 80 in the illustrated example is the same as that shown in FIG. 9 described in the conventional example, and a cover 84 is detachably fastened to a main body housing 82 that houses the engine main body. Here, the fastening points are the part J1 near the rear handle 85, the left and right parts J2 and J3 near the C-shaped upper handle 86, and the three parts on the cover 84 side are shown in FIG. A cylindrical pocket 88 for accommodating the fastening bolt assembly 10 as described above is provided, and an annular convex portion 82a is provided at a portion of the main body housing 82 facing the pocket 88.

  As shown in FIG. 4, the pocket 88 receives a tightening load from the multi-wave spring 20 (on which the plain washer 17 is placed) and a lower end portion pressed against the upper flat portion 32 of the fixing nut member 30 described later. 88b.

  Hereinafter, the fastening portion J3 portion on the right side as shown in FIG. 2 will be described as a representative.

  The fastening bolt assembly 10 of the present embodiment shown in FIG. 5 is a cylindrical multiple wave formed by spirally winding a band-shaped square line in which peaks and valleys are continuously formed in a wave shape. A spring 20 (detailed later), a bolt-type rotation operation member 11 in which an engagement pin 15 as a rotation engagement portion is inserted and fixed in the radial direction near the lower end portion, and a retaining and load receiver And a disc-shaped flat washer 17 with an insertion hole.

  The bolt-type turning operation member 11 includes, in order from the top, a minus-grooved head portion 11a, an upper large-diameter portion 11b, an inverted truncated cone portion 11c, an intermediate medium-diameter portion 11d, and a lower small-diameter portion 11f, and a lower small-diameter portion 11f. The engagement pin 15 is provided at a lower portion of the lower portion of the pocket 88, and a step portion (outer peripheral step portion) 13 between the intermediate middle diameter portion 11d and the lower small diameter portion 11f is a locking portion provided on the inner periphery of the pocket 88. 88s (see FIG. 4A) (detailed later).

  The multiple wave spring 20 has an outer diameter that is substantially the same as the outer diameters of the minus-grooved head portion 11a and the flat washer 17 in the bolt-type rotating operation member 11, and is larger than the length of the engaging pin 15 of the lower small-diameter portion 11f. It is formed and is held by extrapolation between the head 11a with a minus groove in the bolt-type turning operation member 11 and a flat washer 17 which is extrapolated above the engaging pin 15 of the lower small diameter portion 11f. . As shown in FIG. 6, this multiple wave spring 20 has four stages of cylindrical laminated portions (21 to 24) in which 5 to 6 windings are laminated in close contact with each other, and are adjacent in the vertical direction. In the respective laminated portions 21-22, 22-23, and 23-24, the crests and the troughs are in contact with each other, and a fine gap S composed of the troughs and the crests is formed between the contact portions. Is formed.

  On the other hand, in the annular convex portion 82a of the housing 82, a fixing nut member 30 constituting a fixed engaging portion with which an engaging pin 15 as a rotating engaging portion of the bolt type rotating operation member 11 is engaged is inserted. It is provided integrally by molding or the like. The fixing nut member 30 has an upper surface flat portion 32 that receives the lower end portion 88b of the pocket 88 in the cover 84. The upper surface flat portion 32 has a lower small diameter of the bolt-type rotation operation member 11 as shown in FIG. An insertion opening 33 is provided in which a circular opening 33a into which the portion 11f is inserted and a rectangular opening 33b through which the engaging pin 15 is inserted are combined. Further, right and left spiral opening inclined surfaces 35 and 35 with which the engagement pin 15 engages are provided approximately 60 ° in front of and behind the left and right rectangular openings 33b of the insertion opening 33. A part of the engaging pin 15 that is guided and sent by the spiral guide inclined surface 35 is dropped into the terminal portions of the spiral guide inclined surfaces 35 and 35 on the circular opening 33a side. Concave portions 36, 36 having an arcuate cross section that are recessed upward (to be pulled up) are provided.

  When the removed cover 84 is attached to the main body housing 82, the pocket 88 portion provided in the cover 84 is used as an annular convex portion 82 a (fixing nut member 30) that is the fastening portion J 1, J 2, J 3 of the main body housing 82. The bolt-type rotation operation member 11 (tightening bolt assembly 10) with the multiple wave springs 20 and the flat washers 17 being inserted is inserted into the pocket 88. Inside the pocket 88, a receiving seat 88d on which the flat washer 17 is placed is provided, and a through hole similar to the insertion opening 33 of the fixing nut member 30 is provided. When inserted into the interior of 88, the bolt-type turning operation member 11 is inserted until the stepped portion 13 is engaged with the engaging portion 88s. In this state, as shown in FIG. The coupling pin 15 is positioned at the start end portion of the spiral guide inclined surface 35 of the fixed nut member 30 constituting the fixed engagement portion (this state is referred to as a rotation angle: 0 °).

  In this state, when the bolt-type rotation operation member 11 is rotated, for example, about 60 ° clockwise, the stepped portion 13 is disengaged from the locking portion 88s, and the bolt-type rotation operation is performed as shown in FIG. The engaging pin 15 of the operation member 11 is pulled down while being guided by the spiral guide inclined surface 35, and the bolt-type rotation operation member 11 is lowered accordingly, and the multiple wave spring 20 is connected to the bolt-type rotation operation member 11. The head 11a is pressed toward the seat 88d to be compressed. Thereby, between each lamination | stacking part 21,22,23,24 adjacent to the up-down direction in the multiplex wave spring 20, a peak part and a trough part are press-contacted strongly, and the detailed shape formed between the contact parts The gap S is made thinner and smaller.

  Then, when the bolt-type turning operation member 11 is further rotated clockwise by about 30 ° (about 90 ° in total) from the rotated state of about 60 °, as shown in FIG. 15 gets over the spiral guide inclined surface 35 and is sent to the recessed portion 36 that is recessed in the upper side of the arcuate section, and is dropped (raised). Therefore, the multiple wave spring 20 is compressed most when the engagement pin 15 gets over the spiral guide inclined surface 35 (when the rotation angle is about 60 ° to 80 °), and when the engagement pin 15 is fitted into the recess 36. The amount of compression of the multiple wave spring 20 is slightly loosened, but this completes the tightening. At the time of completion of the fastening, the engaging pin 15 is pressed against the recess 36 (fixed nut member 30, and eventually the main body housing 82) with a large load by the spring force of the multiple wave spring 20, so that it can be disengaged even near the vibration source. The cover 84 is fastened to the main body housing 82 by performing the tightening operation using the tightening bolt assembly 10 as described above at the fastening portions J1, J2, and J3.

  On the other hand, when removing the cover 84 from the main body housing 82, the bolt-type turning operation member 11 may be rotated counterclockwise as opposed to the above attachment to push the engagement pin 15 out of the recess 36. As a result, the engagement pin 15 is automatically pulled upward by the spring force (repulsive force) of the multiple wave spring 20, whereby the engagement of the engagement pin 15 with the fixed nut member 30 is released, and thus the cover 84 is removed. Can be removed.

  As described above, in the fastening structure of the present embodiment, the bolt assembly 10 for tightening, in which the multiple wave spring 20 is externally held on the bolt-type turning operation member 11, is used. Here, the multiple wave spring 20 of this example has four layers of laminated portions (21 to 24) in which 5 to 6 windings are laminated so that the entire circumference is closely attached. In this way, by using the multi-wave spring 20 having the four-tiered laminated parts 21 to 24, a structure in which one turn (single turn) is vertically stacked by the number of turns as in a conventional coiled wave spring. As a result, a remarkably large tightening load can be obtained.

  That is, in the conventional coiled wave spring, the single-winding parts adjacent in the vertical direction are in contact with the top of the peak and the bottom of the valley, but the other parts are separated from each other. The tightening load) is obtained by connecting a single winding portion in series for the number of turns.

  On the other hand, in the multiplex wave spring 20 of this example, since the laminated portions 21 to 24 are in close contact with each other, each laminated portion (21 to 24) is equivalent to the case where the number of turns is connected in parallel. In this type of coil spring, the spring force (clamping load) of the coil springs connected in parallel is significantly larger than that connected in series. Therefore, in the multiplex wave spring 20 of this example, the conventional one does not have a sufficient clamping load. It is possible to obtain a sufficient tightening load even at the place where was.

  Therefore, in the fastening structure for fastening the two members of the present embodiment in a detachable manner, a sufficient tightening load can be obtained even with a small rotation operation angle of, for example, about 90 °, and the attachment / detachment operation is performed easily and quickly. be able to. Further, since the tightening load can be increased even with a small rotation operation angle, it is difficult to cause loosening due to vibration. Furthermore, since the multiple wave spring 20 is a single part, the number of parts and the occupied space can be reduced, and the seat surface can be depressed or buckled due to misassembly or uneven load compared to the case where a large number of disc springs are used. Can hardly occur.

  Further, since only the single fastening bolt assembly 10 is separated from the main body housing 82 and the cover 84, it takes less time to attach and detach the two members, and the advantage that necessary parts are not easily lost. can get.

  In the above embodiment, as the multiple wave spring, one having two convex peaks on the upper surface side and two convex valleys on the lower surface side is used. It is possible to use a structure in which three or more convex ridges are provided on the upper surface side, and convex valleys are provided on the lower surface side with predetermined angular intervals in the circumferential direction. Of course, the number of turns and the number of stages are not limited to the above-described embodiment. In FIG. 8, the number of turns of the laminated portions 21 ′ to 24 ′ is 7 to 8 turns, and each of the four convex valleys on the upper surface side and the lower convex valleys on the lower surface side is equiangular. A tightening bolt assembly 10 'using a provided multi-wave spring 20' is shown.

DESCRIPTION OF SYMBOLS 10 Tightening bolt assembly 11 Bolt type rotation operation member 15 Engagement pin (rotation engagement part)
17 Plain washer 20 Multiple wave springs 21-24 Laminated part 30 Fixed nut member (fixed engaging part)
32 upper surface flat portion 33 insertion opening 35 spiral guide inclined surface 36 recess 80 chain saw 82 main body housing (first member)
82a Toroidal convex portion 84 Cover (second member)
88 pockets

Claims (9)

A fastening structure for detachably fastening the second member to the first member,
A cylindrical multi-wave spring in which crests and troughs are continuously formed in a wavy shape and spirally wound in a strip-like square line, and a bolt-type rotation with a rotating engagement part at the bottom A fastening bolt assembly that is externally held by the operation member is provided, and a fixed engagement portion that engages with the rotational engagement portion is provided on the first member side, and the fastening bolt The assembly is rotated by a predetermined angle while being inserted into the first member side through the second member until the rotational engagement portion is positioned at the start end of the fixed engagement portion. Due to the engagement between the dynamic engagement portion and the fixed engagement portion, the bolt-type rotation operation member is pulled down while compressing the multiple wave spring, and the second member is tightened to the first member. Fastening structure for fastening two members detachably, characterized by being fixed   The multi-wave spring has a plurality of cylindrical laminated portions in which two or more windings are laminated in close contact with each other, and between each laminated portion adjacent in the vertical direction, there are peaks and valleys. 2. The fastening structure according to claim 1, wherein a mesh-like gap formed by a valley portion and a mountain portion is formed between the contact portions.   The rotation engagement portion is configured by an engagement pin provided near a lower end portion of the bolt-type rotation operation member, and the fixed engagement portion is a spiral guide inclined surface with which the engagement pin is engaged. The fastening structure according to claim 1, further comprising: a concave portion into which the engaging pin that is guided and sent by the spiral guide inclined surface is dropped.   The length of the engagement pin is made smaller than the outer diameter of the multiple wave spring, the fixed engagement portion is provided with an insertion opening through which the engagement pin is inserted, and the lower end portion of the second member The fastening structure according to claim 3, further comprising an upper flat portion that receives the upper surface.   The fastening structure according to claim 4, wherein an annular convex portion is provided at a portion where the second member around the fixed engagement portion faces. A step portion is provided on the outer periphery of the bolt-type rotation operation member, and a locking portion is provided on the inner periphery of the second member.
When the bolt assembly for tightening is inserted into the first member side through the second member until the stepped portion is locked to the locking portion, the rotation engaging portion is fixed to the fixing member. The fastening structure according to any one of claims 1 to 5, wherein the fastening structure is positioned at a start end portion of the joint portion.   When the tightening bolt assembly is rotated, the stepped portion is disengaged from the locking portion, and the bolt-type rotating operation member is pulled down while compressing the multiple wave spring. The fastening structure according to claim 6.   The multi-wave spring is characterized in that there are three or more convex ridges on the upper surface side and three or more convex valleys on the lower surface side at predetermined angular intervals in the circumferential direction. The fastening structure according to any one of 1 to 7.   A cylindrical shape in which crests and troughs are continuously formed in a wavy shape and spirally wound in a strip shape, and the entire circumference is closely attached and two or more turns are stacked. A tightening bolt assembly in which a multi-wave spring having a plurality of stacked portions is externally held by a bolt-type rotation operation member having a rotation engagement portion provided at a lower portion.

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