JPH0452485Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to a screw fastening device, and particularly to a screw fastening device screwed together with a large diameter bolt.

[Prior Art] A nut is normally used as a screw tightening device for tightening with a large diameter bolt, and a special tool such as a bolt tensioner is generally used to ensure the tightening force.

[Problem to be solved by the invention] As mentioned above, the conventional fastening device for large diameter bolts uses a bolt tensioner, etc., and is tightened with a nut. Since tools are required and the nut to be tightened has a large diameter, the tightening force requires an extremely large amount of force, and all of the above results in a very large amount of personnel and time required for the tightening action. As a result, there was a need to overcome these problems.

This idea was created to solve the above problem.The tightening force around the bolt is uniform and constant, and it can be tightened quickly and accurately by a small number of people without using large special tools. The purpose is to obtain a screw fastening device that can be obtained.

[Means for Solving the Problems] The screw fastening device according to the invention includes a screw member that is screwed into the threaded portion of a large-diameter bolt and has a plurality of internal threads drilled around the threaded portion. , a cylindrical housing that is fitted into the threaded member, has an end surface on the side of the member to be tightened abutting the member to be tightened, and is provided with a hollow hole substantially concentrically corresponding to the female thread of the threaded member; , and a plurality of axial force management type bolts that are screwed into the female threads and are provided through the blank holes.

[Function] Since this invented device is constructed as described above, when tightening, after screwing the threaded member into the threaded portion of the large diameter bolt, the cylindrical housing is placed over the threaded member, and then When each axial force management type bolt is inserted into the hole and its tip is screwed into the female thread of the threaded member, each axial force management type bolt tightens the cylindrical housing to the member to be tightened with a constant force, and The clamping member is clamped evenly by the circumference of the cylindrical housing.

[Example] Hereinafter, this invention will be explained based on the drawings showing one example of the invention.

FIG. 1 shows a large diameter bolt to which a screw fastening device is applied, and this bolt 1 has a threaded portion 2 and a notch 3 formed at the top.

FIG. 2 shows a screw member 4 constituting a screw fastening device, which has a threaded portion 5 in the center that screws into the threaded portion 2 of the bolt 1, and a plurality of internal threads around the threaded portion 5. 6 is drilled. Note that this threaded member 4 is provided with a stepped portion in the axial direction on its outer diameter side, and a female thread 6 is formed below the surface of this stepped portion, but this is basically necessary. isn't it.

Next, what is shown in FIG. 3 is a housing 7 that constitutes a screw fastening device.The inner diameter side of the housing 7 is fitted onto the outside of the screw member 4, and its height is tightened so that the bolt 1 can be inserted by a predetermined amount. The height is set at such a level that it comes into contact with the screw member when extended. Further, the end surface 8 of the housing 7 on the side of the member to be tightened comes into contact with the member to be tightened. Furthermore, the female thread 6 of the screw member 4
A hole 9 is provided which is substantially concentric with respect to the hole. Of course, a hole 10 through which the bolt 1 passes is provided in the center.

Next, the one shown in FIG.
The locking washer 12 is a locking washer 12 that is fitted to prevent loosening, and a hole 13 is formed to correspond to the hole 9 of the housing 7.

What is shown in FIG. 5 is an axial force management type bolt 1 that passes through each hole 13 of a locking washer 12 and each hole 9 of a housing 7 and is screwed into a female thread 6.
It is 4. These are of a type in which the rotating part idles when a predetermined tightening axial force is reached when screwed in (see Japanese Patent Publication No. 4-20090), for example,
SP lock (product name) or a type in which the rotating part cannot be rotated, such as Rota
Bolt (product name) etc.

This idea is structured as above, so
When assembled as shown in FIG. 6 and the axial force management type bolt 14 is not tightened, the housing 7
A clearance 15 larger than the tightening allowance of the bolt 1 is provided between the end face of the inner diameter portion of the screw member 4 and the end face or top face of the screw member 4 .

Next, the assembly order of the above embodiment will be explained.

(1) Screw the screw member 4 into the bolt 1 and tighten it lightly (temporarily).

(2) Fit the housing 7 onto the top of the screw member 4.

(3) Align the locking washer 12 with the notch 3 of the bolt 1 and place it on the top of the housing 7.

(4) Align the female thread 6 of the screw member 4, the hole 9 of the housing 7, and the hole 13 of the locking washer 12, and insert the axial force management type bolt 14 into each hole.
Insert it, screw it into the female thread 6, and tighten it in sequence.

(5) Tighten the axial force management type bolt 14 repeatedly,
Tighten until the specified condition is reached to complete the fastening work.

Since this invention is constructed and assembled as described above, the total tightening force of the axial force management type bolt 14 becomes the tightening force of the bolt 1, and this tightening force is equal to the tightening force of the bolt 1.
will be evenly distributed around the threaded portion 2 of.

The screw fastening device according to this invention can apply a tightening force evenly and accurately even if the bolt 1 has a large diameter, so it can be used for fixing the foundation of a prime mover in a large plant, etc., or for fixing a large flanged pipe. joint part,
Alternatively, it is most effective for use in other fastening parts using large screws that require axial force management.

[Effects of the invention] As described above, according to this invention, there is provided a threaded member having a threaded part that is threaded into the threaded part of a bolt and having a plurality of internal threads drilled around the threaded part; a housing that is fitted into the threaded member, has an end surface on the side of the tightened member abutting the tightened member, and is provided with a blind hole substantially concentrically corresponding to the female thread of the screw member; and Since it is equipped with multiple axial force management type bolts that are screwed into the bolts and passed through the holes, there is no need for special tools to apply large rotational torque for tightening the bolts, making the tightening work easier. In addition, since axial force management type bolts are used, axial force management is completely easy by simply checking that the rotating parts are unable to rotate or are in the specified state such as idling. Furthermore, since the axial force management type bolt stretches elastically, it also has the effect of acting as a kind of spring body, and therefore has the effect of providing a screw fastening device that prevents loosening of tightening and prevents a reduction in axial force. have. Furthermore, since the cylindrical housing has a linear or band-shaped area on the circumference of the end face of the member to be fastened, it is possible to tighten the member to be fastened evenly in a linear or band-like manner. The axial force management type bolt always tightens to a constant value without applying local stress to the attached member, without damaging or deforming the member to be tightened, and with this, stable tightening is achieved. It also has the effect of obtaining a state.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the end of the bolt into which the screw fastening device of this invention is screwed, Fig. 2 is a perspective view of an embodiment of the screw member constituting the screw fastening device of this invention, and Fig. 3 is also a perspective view of the end of the bolt into which the screw fastening device of this invention is screwed. FIG. 4 is a perspective view of a locking washer used in this device, and FIG. 5 is a perspective view of an example of an axial force management type bolt forming this device. Figure, 6th
The figure is an assembled sectional view of each member shown in FIGS. 1 to 5. 1...Bolt, 4...Threaded member, 5...Threaded portion, 6...Female thread, 7...Housing, 8...End face, 9...Diaper hole, 14...Axial force management type bolt.

Claims (1)

[Scope of utility model registration request] A screw member that has a threaded portion that screws into a large-diameter bolt and has a plurality of female threads drilled around the threaded portion, and a threaded member that is fitted into the threaded member and that comes into contact with the member to be tightened. a cylindrical housing that is in contact with the female thread and is provided with a blind hole substantially concentrically corresponding to the female thread of the threaded member; and a plurality of axial force management types that are screwed into the female thread and are provided through the stupid hole. A screw fastening device comprising a bolt.