JPS6021859Y2 - Bushing fixing metal fittings - Google Patents

Description

[Detailed Description of the Invention] Technical Field This invention relates to a fixture for attaching a bushing to a switch.

Purpose The purpose of this invention is to provide a bushing fixing fitting for positioning and fixing the bushing to a switch case.

EXAMPLE Hereinafter, an example embodying this invention will be explained with reference to FIGS. sulfur) is injected under pressure.

Reference numeral 4 denotes a mounting base which is formed by applying a narrowing process to the upper wall 1a of the case 1 common to each phase (only one phase is shown) and protrudes upward in a platform shape, forming a circular insertion hole 5. .

Reference numeral 6 denotes an annular protrusion protruding from the inner periphery of the insertion hole 5 of the base 4 into the switch case 1 .

A bushing 7 is fitted into the insertion hole 5 and has an appropriate number of insulating folds formed on its outer circumferential surface, and has a conductor 8 in its center.
is inserted.

Reference numeral 9 denotes a flange portion protruding from the outer periphery of the lower part of the insulating folds of the bushing 7, and the mounting is performed by forming a step on the inner periphery of the lower surface 9a of the flange portion 9 so as to be secured to the upper surface of the periphery of the insertion hole 5 of the base 4. A portion 9b is formed.

Reference numeral 10 denotes a metal spacer having the same outer diameter as the bushing 7, which is interposed between the lower surface 9a of the flange portion 9 of the bushing 7 and the upper wall 1a of the case 1, and between the metal spacer 10 and the stepped portion 9b of the flange portion 9. An O-ring 11 is interposed.

When the bushing 7 is inserted into the insertion hole 5 and fixed, the thickness of the metal spacer 10 regulates the compression margin of the O-ring 11.

Reference numeral 12 denotes four bolts arranged on the outer periphery of the metal spacer 10, and the bolts are mounted to the base 4 using a flange 12a provided at the base end so that the bolts are equidistant when mounting adjacent to each other. Fixed by welding.

Reference numeral 13 denotes a rectangular cylindrical fixing fitting which is fitted over the bushing 7 so as to cover the upper surface 9C and the outer circumferential surface of the flange portion 9 of the bushing 7. Through holes 13a are provided at the four corners of the upper surface, and cylindrical holes 13a are provided in the four corners of the upper surface. The bolt 12 is inserted through the bolt 12 via a shaped spacer 14.

13b is an insertion hole provided in the center of the earthen wall of the fixture 13 for insertion of a bushing.

Note that 17 indicates the flange portion 9 of the bushing 7 and the fixing member 1.
This is an annular buffer plate inserted between the two.

Reference numeral 13c denotes four side parts of the fixing metal fitting 13, each of which is formed in a concave shape toward the insertion hole 13b side, and contacts the outer periphery of the flange part 9 of the metal spacer 10 and the bushing 7 from four directions at the same time. The fixed position of the machine is being determined.

Reference numeral 15 denotes a tightening nut, which is screwed onto the mounting bolt 12 via a spring washer 15a, and fastens and fixes the fixture 13 and the bushing 7 to the mounting base 4 of the switch case 1.

In this tightened state, the upper and lower ends of the spacer 14 are connected to the soil wall of the fixing fitting 13 and the flange 1 of the bolt 12 is attached.
2a, and a fixed interval G is formed between the lower edge of the fixing bracket 13 and the top surface of the mounting base 4, and the fixing bracket 1
3 from further downward movement and prevents the flange portion 9 from being over-tightened.

On the other hand, at that time, the O-ring 11 comes into close contact with the lower surface 9a of the flange portion 9 of the bushing 7 to keep the switch case 1 airtight.

Reference numeral 16 denotes an insulating cylinder that covers the upper end of each bushing 7.

Next, to explain the order of assembly of the bushing to the case, first, an O-ring 11 for airtightness is placed around the periphery of the insertion hole 5 in the upper wall 1a of the case 1, and a metal spacer is placed around the outer periphery of the O-ring 11. Place 10.

Then, the bushing 7 is inserted into the insertion hole 5 from above, the lower surface 9a of the flange portion 9 of the bushing 7 is brought into contact with the O-ring 11, and the upper surface of the flange portion 9 is provided with a buffer plate 17.
put

On the other hand, for each installation provided on the stand 4, a spacer 14 is inserted into a bolt 12.

After that, for each installation, the bolt 12 is inserted into each through hole 1 of the fixing fitting 13.
3a, and when the bushing 7 is similarly inserted through the insertion hole 13b, each side portion 13c of the fixing fitting 13 contacts the metal spacer 10 and the outer periphery of the flange portion 9 of the bushing 1 in four directions simultaneously, and both 10 , 7 are easily positioned.

Further, at this time, the O-ring 11 is positioned between the outer periphery of the stepped portion 9b of the bushing 7 and the inner periphery of the metal spacer 10.

Finally, when the nuts 15 are tightened through the spring washers 15a to the ends of the bolts 12, the fixing fittings 13 tighten the flange portions 9 of the bushings 7. By pressing, the flange portion 9 comes into close contact with the O-ring 11 and is fixed to the switch case 1 while maintaining the airtightness of the switch case 1.

Although not directly related to this invention, in this embodiment, the spacer 14 is in contact with the flange 12a of the bolt 12, so when the nut 15 is tightened, the spacer 14 is tightened in the lower part of the flange 12a. The installation is on the top wall 1 of stand 4.
A is not deformed, and on the other hand, the spacer 14 forms a certain gap G between the lower edge of the fixture 13 and the top surface of the mounting base 4, preventing further downward movement of the fixture 13.

Therefore, tightening with excessive torque can prevent damage to the flange portion 9 of the bushing 7 when the nut 15 is tightened.

The present invention is not limited to the above-mentioned embodiments, but can also be used to fix bushings of general switches by using a cushioning material as the spacer 10.

Effects As detailed above, this invention has an excellent effect in that the bushing 7 can be easily positioned by forming the side part in a concave shape toward the insertion hole 13b so as to come into contact with the outer peripheral part of the flange part 9 of the bushing. play.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view showing an embodiment of this invention, showing how the switch bushing is installed, Fig. 2 is an exploded perspective view, and Fig. 3 is a cross-sectional view taken along the line A-A in Fig. 1. It is. Case 1, upper wall 1a, bushing 7, flange part 9, fixing fittings 13, side part 13c0

Claims (1)

[Scope of utility model registration request] The whole is formed into a square tube shape, and there is one bushing insertion hole on the top surface.
3b and the upper wall 1a of the case 1 are provided with through holes 13a for inserting bolts for tightening and fixing.
A fixing metal fitting for a bushing, characterized in that it is formed in a concave shape toward the b side so as to come into contact with the outer periphery of the flange portion of the bushing 7.