JPH09330636A - Detent structure for bushing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a detent structure for a bushing wherein rotation of the bushing can be prevented even by small pressing force. SOLUTION: In this constitution, a flange part 15 formed in a peripheral surface of a bushing 12 is pressed to a side of a switch case 11 by a retaining cover 17, also so that the flange parts 15 of the adjacent bushings 12 are brought into contact each other. That is, the flange part 15 is interposed by the switch case 11 and the retaining cover 17, in addition, brought into contact with the flange part 15 of the adjacent other bushings 12, so as to increase resistance, given to the bushing 12 in the case of rotating relating to the switch case 11, larger than in the past. In this way, the bushing 12 is markedly prevented from easily rotating relating to the switch case 11. As a result, rotation relating to the switch case 11 can be prevented sufficiently even by tightening force of a small nut 22, in its turn, assembly workability of a switch is improved, deformation of the retaining cover 17 can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bushing detent structure which is attached through a plurality of side surfaces of a case of a switch.

[0002]

2. Description of the Related Art Generally, a plurality of bushings are attached to front and rear surfaces of a case of a switch, a power transmission line is mounted outside the case, and a fixed electrode connected to the power transmission line is provided inside the case. ing. Then, the fixed electrodes of both bushings are connected or separated by the movable electrodes, so that power is supplied or stopped.

As shown in FIG. 9, the bushing 62 is provided before and after a case 61 (only one of which is shown) constituting a switch.
Are attached by penetrating each three phases. When the bushings 62 are attached to the case 61, the bushings 62 are arranged in parallel while maintaining a predetermined interphase distance. Then, the flange portion 63 of each bushing 62 is covered with the pressing cover 64, and the pressing cover 64 is covered with the bolt 65 and the nut 6.
Tighten and fix with 6. As a result, the pressing cover 64
Presses the flange portion 63 toward the case 61 side, and the back surface of the flange portion 63 is pressed toward the case 61 side to push the bushing 62.
Is prevented from rotating. Further, the pressing force of the pressing cover 64 causes the case 61 and the flange portion 6 to
The O-ring (not shown) sandwiched between 3 and 3 is compressed, and airtightness inside and outside the case 61 is maintained.

[0004]

However, the above-mentioned conventional technique has the following problems. (1) In order to prevent the bushing 62 from rotating with respect to the case 61, it is necessary to strongly press the flange portion 63 toward the case 61 side by the pressing cover 64.
This is because the bushing 62 may rotate with respect to the case 61 when the pressing force of the pressing cover 64 is small. Bushing 62 for case 61
If it rotates, it may not be able to open or close, or contact failure may occur. For this reason, it is necessary to strongly press the flange portion 63 toward the case 61 by the pressing cover 64. However, in order to strongly press the flange portion 63, the nut 66 must be strongly tightened, which deteriorates the assembling workability and may deform the pressing cover 64.

(2) In order to reduce the interphase pitch in order to reduce the size of the switch, it is necessary to reduce the outer diameter of the circular flange portion 63. As the diameter of the flange portion 63 becomes smaller, the contact area between the case 61 and the flange portion 63 becomes smaller. The frictional force between the two decreases as the contact area decreases. Therefore, when the inter-phase pitch is reduced, the pressing force of the pressing cover 64 has to be increased, and the problem (1) above tends to occur.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a bushing detent structure capable of preventing the bushing from rotating even with a small pressing force.

[0007]

In order to achieve the above object, according to the invention as set forth in claim 1, in a detent structure for a bushing which is attached through a plurality of switch cases, the outer peripheral surface of the bushing is provided. While pressing the formed flange portion to the switch case side by the pressing member and bringing the flange portions of the adjacent bushings into contact with each other, the rotation of the bushing with respect to the switch case is prevented. Use as a summary.

According to a second aspect of the invention, the gist of the invention is that a flat surface portion is provided on the outer peripheral surface of each of the flange portions, and the flange portions are in contact with each other on the flat surface portion. In the invention according to claim 3, the pressing member presses the flange portion toward the switch case based on the tightening operation of the bolt and the nut, and the flange portion does not interfere with the bolt. The gist of this is that a relief portion is provided in the.

The invention according to claim 4 is characterized in that the flange portion is formed in an octagonal shape.
Therefore, in the invention according to the first aspect, the flange portions of the adjacent bushings are in contact with each other so that the rotational movements of the bushings are mutually restricted. This prevents the bushing from rotating with respect to the switch case even if the pressing force of the pressing member that presses the flange portion is reduced.

According to the second aspect of the invention, in addition to the function of the first aspect of the invention, the flat portions provided on the outer peripheral surface of the flange portion are in contact with each other, so that the switch case can be more reliably provided. Bushing rotation is prevented.

According to the invention described in claim 3, in addition to the function of the invention described in claim 1 or 2, the pressing member is further provided with an escape portion so as not to interfere with the bolt. It can be close to the member.

In the invention described in claim 4, in addition to the function of the invention described in any one of claims 1 to 3, since the flange portion is formed in an octagonal shape, the left and right sides thereof are adjacent to each other. And the oblique side thereof is the relief portion.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment in which the present invention is embodied in a gas switch will be described below with reference to the drawings. As shown in FIG. 1, bushings 12 made of magnetism or the like are penetratingly attached by three phases to front and rear surfaces (left and right in FIG. 1) of switch case 11. Switch case 1 for bushing 12
The fixed electrode 13 is supported in the inside of the unit 1.

As shown in FIG. 3, a flange portion 15 is integrally formed on the outer peripheral surface of the bushing 12. An O-ring 16 is attached to the surface of the flange portion 15 facing the switch case 11. By sandwiching the O-ring 16 between the switch case 11 and the flange portion 15, the inside and outside of the switch case 11 can be hermetically sealed.

As shown in FIGS. 2 and 4, the outer shape of the flange portion 15 is an octagon, and in the present embodiment, the octagon is not a regular octagon. That is, the distance of the vertical line L1 connecting the upper side H1 to the lower side H2, and the left side H3 to the right side H
It is different from the distance of the horizontal line L2 connecting the four (vertical line L1
<Horizontal line L2).

As shown in FIGS. 1 to 4, each flange portion 15 is covered with a pressing cover 17. The pressing cover 17 is formed in a horizontally long rectangular shape, and a through hole 18 is formed corresponding to each bushing 12. Further, the bushing 12 is provided on the rear surface side of the pressing cover 17.
An accommodation recess 19 for accommodating the flange portion 15 is formed. The depth of the accommodation recess 19 is shallower than the thickness of the flange portion 15. Also, the vertical width W of the accommodation recess 19
1 is slightly larger than the vertical line L1 of the flange portion 15. The lateral width W2 of the housing recess 19 is about three times the horizontal line L2 of the flange portion 15.

Further, bolt insertion holes 20 are formed at four corners on the front surface of the pressing cover 17 and at four upper and lower portions of the boundary portion of each through hole 18. Bolts 21 protruding from the outer surface of the switch case 11 are provided in the respective bolt insertion holes 20.
Is inserted. A nut 22 is screwed into the bolt 21 from the front surface side of the pressing cover 17. Corresponding to the tightening force of the nut 22, the pressing cover 17 presses the flange portion 15 of the bushing 12 against the side surface of the switch case 11.

In this embodiment, the following effects can be obtained by the configuration as described above. (1) The flange portion 15 formed on the outer peripheral surface of the bushing 12 is pressed by the pressing cover 17 toward the switch case 11, and the flange portions 15 of the adjacent bushings 12 are in contact with each other. That is, since the flange portion 15 is sandwiched between the switch case 11 and the pressing cover 17, and also comes into contact with the flange portion 15 of another bushing 12 adjacent thereto, the bushing 12 of each phase.
Is locked so as not to rotate relative to the bushing 12 of the other phase, and is mounted as a three-phase integrated bushing body. As a result, each bushing 12 does not rotate with respect to the switch case 11. As a result, it is not necessary to consider the tightening force of the nuts 22 so much, and each bushing 12 is attached to the switch case 1 with a smaller tightening force of the nuts 22 than the conventional one.
It is possible to fix it to No. 1 and to improve the workability of assembling the switch and prevent the pressing cover 17 from being deformed.

(2) Each flange portion 15 is a flat surface (left side H
3, by making the right side H4) contact each other,
It is possible to more reliably prevent the bushing 12 from rotating with respect to the switch case 11, further improve the workability of assembling the switch, and prevent the pressing cover 17 from being deformed. Further, since the rotation of the bushing 12 with respect to the switch case 11 can be reliably prevented, it is also possible to reduce the interphase pitch of the bushing 12 (the flange portion 15 is small), and the switch can be downsized. it can.

(3) Since the flange portion 15 is formed in an octagonal shape, the bolt 21 can be further tightened in the flange portion 15.
It is possible to make it close to. That is, the octagon has a hypotenuse, and the hypotenuse serves as a clearance for the bolt 21,
It is possible to bring the bolt 21 closer to the flange portion 15 than to the square flange portion 15 that merely serves to prevent the bushing 12 from rotating. As a result, the switch case 11 of the O-ring 16 for keeping the inside and outside of the switch case 11 airtight
It is possible to improve the adhesion to the flange portion 15.

(4) Since the shape of the flange portion 15 is an octagonal shape in which the vertical line L1 and the horizontal line L2 are different from each other, it can be used for two types of switches having different phase pitches.
That is, as shown in FIG.
It is maintained in a state of being rotated by 90 ° from the above state.
Therefore, in this case, the vertical line L1 is arranged in the horizontal direction, and the horizontal line L2 is arranged in the vertical direction. Therefore, when the bushing 12 is held in the state shown in FIG.
The interphase pitch is narrower than in the state of FIG. in this way,
In this embodiment, since one bushing 12 can be used for a switch having two different types of interphase pitches,
It also leads to cost reduction.

(5) Each flange 15 has at least 2
By contacting the side with the inner peripheral surface of the housing recess 19 of the pressing cover 17, the bushing 12 can be more reliably prevented from rotating with respect to the switch case 11.

The present invention may be implemented as follows. (1) As shown in FIG. 6, the flange portion 32 of the bushing 31 has a substantially oval shape, or as shown in FIG. 7, the flange portion 42 of the bushing 41 has a substantially square shape. Escape portions 43 for inserting the bolts 21 are provided at the four corners. Even with this configuration, the same effect as in the above embodiment can be obtained.

The shape of the bushing flange is
It may be embodied by forming a hexagonal shape, another polygonal shape, or contacting adjacent flange portions in a concave-convex relationship.

(2) The number of the bushings 12 mounted on the switch case 11 may be other than three (three phases). (3) As shown in FIG. 8, the pressing covers 51, 52 as pressing members may be embodied by providing walls 51a, 52a in contact with the peripheral surface of the flange portion 15 of the bushing 12, respectively. That is, the bushing 1 is attached to the pressing covers 51 and 52.
The wall 51 that contacts at least one side of the second flange portion 15
If a and 52a are provided, the bushing 12 can be prevented from rotating.

(4) Pressing cover 1 as a pressing member
7 may be embodied as a simple plate-like member having no recess.

[0027]

As described above in detail, according to the invention described in claim 1, the resistance imparted to the bushing when rotating with respect to the switch case is brought about by bringing the adjacent flange portions into contact with each other. Will increase. This makes it difficult for the bushing to rotate with respect to the switch case, and the pressing force of the pressing member that presses the flange portion can be reduced. As a result, the workability of assembling the switch can be improved and the pressing member can be prevented from being deformed.

According to the invention described in claim 2, according to claim 1,
In addition to the effect of the invention described in (1), the flat portions of the flange portion contact each other, so that the rotation of the bushing with respect to the switch case can be prevented more reliably. As a result, it is possible to further improve the assembling workability of the switch and prevent the pressing member from being deformed.

According to the invention described in claim 3, according to claim 1
Alternatively, in addition to the effect of the invention as set forth in claim 2, since the bolt can be brought close to the pressing member, the adhesion between the switch case and the flange portion can be improved, and thus the airtightness inside and outside the switch case can be improved. .

According to the invention described in claim 4, since the flange portion is formed in an octagonal shape, the left and right sides thereof are contact portions with the adjacent flange portions, and the oblique side thereof is the relief portion. Become. As a result, it is possible to obtain the effects that cover the inventions described in claims 1 to 3.

[Brief description of drawings]

FIG. 1 is a side sectional view of a switch according to an embodiment of the present invention.

FIG. 2 is a partial perspective view of the switch according to the embodiment.

FIG. 3 is a partial side sectional view of a switch according to an embodiment.

FIG. 4 is a partial front sectional view of a switch according to an embodiment.

FIG. 5 is a partial front sectional view of the switch according to the embodiment.

FIG. 6 is a front view of a bushing according to another embodiment.

FIG. 7 is a front view of a bushing according to another embodiment.

FIG. 8 is a perspective view of a pressing cover according to another embodiment.

FIG. 9 is a partial front view of a switch showing a conventional bushing mounting structure.

[Explanation of symbols]

11 ... Switch case, 12, 31, 41 ... Bushing,
15, 32, 42 ... Flange portion, 17 ... Pressing cover as pressing member, 21 ... Bolt, 22 ... Nut, H1
-H4 ... Top and bottom sides and right and left sides as a plane part, H5 ... oblique side as a relief part, 43 ... a relief part.

Claims (4)

[Claims] 1. A detent structure for a bushing that is attached to a switch case through a plurality of holes, wherein a flange portion formed on the outer peripheral surface of the bushing is pressed toward the switch case by a pressing member,
A bushing rotation preventing structure, characterized in that the flange portions of adjacent bushings are brought into contact with each other to prevent the bushing from rotating with respect to the switch case. 2. The detent structure for a bushing according to claim 1, wherein a flat surface portion is provided on an outer peripheral surface of each of the flange portions, and the flange portions are in contact with each other on the flat surface portion. 3. The pressing member presses the flange portion toward the switch case based on a tightening operation of a bolt and a nut, and the flange portion has a relief portion so as not to interfere with the bolt. The bushing detent structure according to claim 1 or 2, which is provided. 4. The detent structure for a bushing according to claim 1, wherein the flange portion is formed in an octagonal shape.