JP3342675B2 - Article tightening device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a non-circular cross-section having a projection between a flat dish-shaped portion for tightening and receiving and a threaded part, which partly or entirely projects radially outward from the threaded part. The present invention relates to an article tightening device including a bolt having a rotation preventing portion.

[0002]

2. Description of the Related Art A countersunk bolt provided with a detent portion engages a dish-shaped head with a recess provided on an article, and engages the detent with a locking portion (hole) provided in the recess. When the articles are fastened to each other with the nut screwed into the threaded rod part, the fastening operation with the nut is performed smoothly without rotating together with the nut due to the engagement relationship between the locking part and the detent part. However, the head for tightening is composed of a flat body,
The head may be broken at the time of fastening because the movement in the rotation direction is restricted by the engagement relationship at the time of fastening and the fastening load is concentrated in the axial direction.

In view of the above, the present invention has been devised in order to provide a device having a tightening load resistance and capable of performing an operation of tightening an article only by a screwing operation of a nut to a screw rod portion. is there.

[0004]

A non-circular detent having a non-circular cross section having a projecting portion projecting from the screw portion is provided between the flat dish-shaped head for tightening and receiving and the screw portion. And a bolt provided with a swelling portion for preventing breakage that overlaps the entirety of the protruding portion at the center of the upper surface of the head,
The bolt is recessed into the head and is fitted with the locking claw washer and the screwing part, which are provided with a locking hole that matches the outer shape of the detent and the locking hole and communicates with the recess. And a nut for tightening the article.

[0005]

1 shows an embodiment of an article tightening apparatus according to the present invention. FIG. 1 is a front view of a bolt, FIG. 2 is a plan view of the bolt, FIG. 3 is a bottom view of the bolt, and FIG. 5 is a partially enlarged front view of the bolt, and FIG. 6 is a partially cut front view of the bolt.

In the drawing, A is a bolt, and the bolt A is constituted by interposing a detent member 3 between a threaded rod portion 1 provided with a screw on the tip side and a head portion 2 for tightening reception. Reference numeral 3 denotes a rectangular cross-section, and includes four protrusions 3 ′, 3 ′, 3 ′, and 3 ′ that project four corners of the rectangular shape radially outward of the screw rod 1, and is tightened by a nut 4. At this time, co-rotation with the nut 4 is restricted.

The head 2 serves as a tightening support during the tightening operation, and has a flat and slightly frustoconical shape.
At the center of the upper surface 2 ′, there is provided a bulging portion 5 having a flat upper surface (which can be formed with a minimum necessary material by flattening), and an outer peripheral end 5 ′ of the bulging portion 5. The detent portion 3 is arranged at a position surrounding the head portion 2 in a plan view, and the detent portion is detented so as to overlap with the detent portion 3 including the protruding portions 3 ', 3', 3 ', 3'. The diameter b is larger than the diameter a of the portion 3.

The head 2 is formed into a flat truncated conical shape so that it can be immersed in a recess 7 formed in the washer 6 locked to the cross member 11 by a locking claw as shown in FIG. Unnecessary protrusions from 6 are not generated.

As shown in FIG. 6, the washer 6 is configured such that a locking claw (reference numeral is omitted) is inserted into an article (the horizontal member 11 in the embodiment) and fixed to the article to be used. Recess 7
And a locking hole 13 communicating the recess 7 with the locking hole 13.
Is the bolt A with the nut 4 in conformity with the outer shape of the detent part 3.
To prevent co-rotation.

[0010] For example, as shown in FIG. 6, a joining metal fitting 12 for joining a wooden vertical member (post) 10 and a wooden horizontal member (horizontal member) 11 (not to mention specific examples) is used. The present device is used to fasten the cross member 11, and the other side of the joint fitting 12, one side of which is attached to the vertical member 10, is provided with the cross member 11 and a locking claw on the cross member 11. The screw device 1 is made to penetrate through the washer 6 fixed by the above, and the nut 4 is screwed and fastened to the tip of the screw device 1 protruding from the joint fitting 12 to obtain the present apparatus.

Although the detent portion 3 has a square shape in the embodiment, it is sufficient that a part or the whole of the screw portion 1 has a non-circular cross section projecting radially outward.

[0012]

The present invention has the configuration described above,
The head can be engaged and housed in the recess formed in the washer, and the tightening operation of the article can be performed only by the screwing operation of the nut. When tightening the nut, the lower surface of the head which is the boundary with the detent portion Even if a tensile force acts on the portion, the lower surface portion of the head overlaps with the bulging portion for preventing breakage, so that the lower surface portion of the head is reinforced, and the portion due to the flatness of the head is caused. It is possible to provide an article tightening device that does not break (break) the bolt from the wrench.

[Brief description of the drawings]

FIG. 1 is a front view of a bolt.

FIG. 2 is a plan view of a bolt.

FIG. 3 is a bottom view of the bolt.

FIG. 4 is a sectional view taken along line xx of FIG. 1;

FIG. 5 is a partially enlarged front view of the bolt.

FIG. 6 is a partially cutaway front view of the bolt.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Screw part 2 Head part 3 Detent part 4 Nut 5 Swelling part 6 Washer 7 Recess part

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F16B 35/04 F16B 43/00 E04B 1/38

Claims (1)

(57) [Claims] 1. A non-circular detent having a non-circular cross-section having a projection projecting from the screw portion between a flat dish-shaped head for tightening reception and the screw portion, and overlapping with the screw portion, and ,
A bolt provided with a bulging portion for preventing breakage that overlaps the entirety of the projecting portion at the center of the upper surface of the head, conforms to the outer shape of the recessed portion for recessing the head of the bolt and the detent portion, In addition, an article tightening device including a lock washer with a locking claw provided with a locking hole communicating with the concave portion and a nut screwed into the screwing portion to tighten an article.