JPH0350572Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a circuit breaker that interrupts a circuit in response to an overcurrent, and particularly to a sealed type circuit breaker whose interior is sealed from the outside.

The circuit breaker may be exposed to the outside, for example when it is installed in a two-wheeled vehicle, and in this case it is necessary to make the circuit breaker waterproof. In addition, the circuit breakers used to protect the speaker coils inside the speaker box do not contain harmful gases (chlorine gas, formalin, formic acid, etc.) from the adhesive used to make the plywood (particle board) that is the material of the speaker box. (contains)
This deteriorates the bimetallic part of the circuit breaker, making its breaking characteristics worse. Therefore, when installing a circuit breaker in such a location, it is necessary to make the circuit breaker a sealed type.

Since it is expensive to specifically design and manufacture a sealed circuit breaker, conventionally, an unsealed circuit breaker has been covered with a cover to provide a sealed structure.
However, conventional sealed structures are expensive. First, we will briefly describe the configuration of a conventional circuit breaker, and then explain the conventional sealing structure for the circuit breaker.
Then, the sealed circuit breaker according to this invention will be explained.

FIG. 1 shows an example of a conventional unsealed manual reset type circuit breaker. The case 11 has a rectangular parallelepiped shape and is constructed as a molded product of synthetic resin, and its front plate is removed as a lid, although it is not shown in the figure. The left and right side plates 11a of this case 11,
Terminals 12 and 13 are attached to the bottom plate 11c of the case 11 near the terminal 11b so as to protrude inwardly and outwardly. A slit 14 is formed from the front near the left side plate 11a of the bottom plate 11c, and the intermediate part of the terminal 12 is inserted and fitted into the slit 14, and the terminal 1
2 is bent at a substantially right angle toward the right side plate 11b, and a fixed contact 15 is attached to the bent portion. The bottom plate 11c is almost in contact with the right side plate 11b.
A slit 16 is formed from the front surface of the slit 16, the middle part of the terminal 13 is fitted into the slit 16, and the inner end part of the terminal 13 is bent to the left at a substantially right angle.
One end portion of the bimetal 17 is fixed to the bent plate portion.

The bimetal 17 extends between the left and right side plates 11a and 11b and is disposed in the middle of the case 11, and a movable contact 18 is fixed near its free end. The movable contact 18 can come into contact with and move away from the fixed contact 15. One end of an arcuate spring 19 is engaged with the free end of the bimetal 17 further than the movable contact 18, and the other end of the arcuate spring 19 is engaged with a triangular notch 21 formed in the middle of the left side plate 11a. has been done. When the engagement point of the bimetal 17 and the arcuate spring 19 is closer to the fixed contact 15 than the critical line 22 connecting this locking point and the fixed point of the terminal 13 of the bimetal 17, the movable contact 18 is moved by the arcuate spring 19. It is pressed against the fixed contact 15.

However, through the bimetal 17, terminals 12,1
The current flowing between 3 becomes excessive and bimetal 1
7 is thermally deformed and its engagement point with the arcuate spring 19 moves to the case upper plate 11d side than the critical line 22, the action of the arcuate spring 19 instantaneously closes the movable contact 18.
is separated from the fixed contact 15, and the current path between the terminals 12 and 13 is interrupted. A reset button 23 is provided to reset the cut-off state in which the movable contact 18 is separated from the fixed contact 15 and bring the movable contact 18 into contact with the fixed contact 15. That is, a recess 24 is formed in the middle part of the upper plate 11d of the case 11 from the front side, and a reset button 23 is arranged within the recess 24.
A drive rod 23a is integrally connected to the inner end surface of the reset button 23, and a collar 25 is integrally formed at the inner end of the drive rod 23a. A stopper piece 26 is integrally formed at intervals on the bottom plate 11 side of the upper plate 11d in the vicinity of the recess 24, a hole 27 is formed in the stopper piece 26 from the front side, and a drive rod 23a of the push button 23 is inserted into the hole 27. It is located. Stopper piece 26
A coil spring 28 is wound around the drive rod 23a between the flange 25 and the reset button 23.
is biased toward the inside of the case 11 by a coil spring 28, and a reset button 23 is hooked onto the stopper piece 26. In this state, the collar 25 is in contact with or close to the bimetal 17. Bimetal 17 is thermally deformed and movable contact 18 becomes fixed contact 15
The further apart, the bimetal 17 and the arcuate spring 1
9, the reset button 23 is pushed up against the spring force of the coil spring 28 and protrudes from the case 11 as shown by the dotted line in the figure. When the reset push button 23 is pushed into the case 11 from this protruding state, the bimetal 17 is pushed and the movable contact 18 comes into elastic contact with the fixed contact 15.

In this circuit breaker, slits 14 and 16 are formed for attaching the terminals 12 and 13 to the case, and holes 24 and 27 are also formed for inserting and removing the reset button 23.
The front panel of the case 11 is covered, and there is a small gap around the edge of the cover, which makes the case 11
has a non-sealed structure.

In order to make this circuit breaker a sealed structure, conventionally a circuit breaker main body 32 shown in FIG. 2 is inserted into a sealing case 31 from the open side of the sealing case 31 as shown in FIG. The insertion port side is closed by a cover 33 screwed to the case 31 via a packing 34. Furthermore, a hole is formed in the case 31 in a portion facing the reset button 23, and a hole is formed at the periphery of the hole.
The peripheral edge of the soft resin cap 37 is screwed to the case 31 using the clamp fitting 35 and the packing 36 to close the hole. When the reset button 23 protrudes into the cap 37, the reset button 23 can be pushed into the circuit breaker body 32 by pushing the cap 37.

Furthermore, lead wires 3 are connected to terminals 12 and 13, respectively.
One end of 8, 39 is soldered, and the lead wire 38,
39 is inserted into a common captire cord 41, this captire cord 41 is led out from the case 31, and a packing 4 is inserted around the periphery of the outlet hole.
A clamp fitting 43 is fixed to the case 31 through the clamp 2 to form an airtight structure. As described above, the conventional airtight circuit breaker has a complicated structure for airtightness, and is expensive due to the airtightness, and in some cases, the airtightness is more expensive than the circuit breaker body 32 itself. It was.

This invention provides a sealed circuit breaker that can be made into a sealed circuit breaker at low cost by simplifying the unsealed circuit breaker.

3 to 5 show an example of a sealed circuit breaker according to this invention, and parts corresponding to those in FIGS. 1 and 2 are given the same reference numerals. In this invention, the circuit breaker main body 32 is covered with a main body cover 45 made of a soft material, and one side of the main body cover 45 (the bottom side in the figure) is an open surface 46, and the terminals 12 , 13 are projected. In this example, the present invention is applied to a manual reset type circuit breaker, and therefore a protrusion 46 is provided on the main body cover 45 facing the reset button 23 and having a space that allows the reset button 23 to protrude. are integrally formed.

An auxiliary cover 48 is formed so as to integrally close the peripheral edge surface of the open surface 47 of the main body cover 45 and to wrap around the outer periphery of the terminals 12 and 13. In this example, lead wires 38 and 39 are connected to the terminals 12 and 13 by soldering, and in this state, the auxiliary cover 4
Projections 51 and 52 are integrally formed on the auxiliary cover 48 so as to include the connecting portions between these terminals and the lead wires and reach the outer cover portions of the lead wires 38 and 39. In other words, the terminal 1 is inside the protrusions 51 and 52.
2 and 13 and a portion of lead wires 38 and 39 are embedded. Note that when forming the auxiliary cover 48 including the protrusions 51 and 52, the main body cover 45 is actually attached to the circuit breaker main body 32 as described above.
After covering this, the auxiliary cover 48 and the protrusions 51 and 52 are double molded with resin material to be integrated with the main body cover 45. Therefore, the auxiliary cover 48
does not exist as a part. This auxiliary cover 48
By making the main body cover 45 and the same material, it is possible to ensure that they are in close contact with each other.

As mentioned above, the main body cover 45 is made of a soft material such as polyvinyl chloride, and the reset button 23 can be operated from above the protrusion 47. In the case of the manual reset type, it is preferable that the body cover 45 is made of a transparent resin material so that the protruding state of the reset button 23 can be seen from the outside.
The color of the circuit breaker body 32 and body cover 45
It is preferable that the color is different from the color of . In addition, in the figure, a projecting part 53 is formed on the front side of the main body cover 45, and a slot 54 is formed in the projecting part 53 along the vertical direction thereof.For example, a band is passed through the slot 54 to attach the sealed circuit breaker to another object. Can be installed. Further, in FIG. 4, the case 11 of the circuit breaker main body 32 is shown in a state in which the front plate 11e is configured as a lid.

According to this embodiment described above, the main body cover 4
5 is made inexpensively as a molded product of synthetic resin material, and it is a simple task to cover the circuit breaker 32 with it.Furthermore, by forming the auxiliary cover 48 by molding, the main body cover can be replaced. Since the auxiliary cover 45 and the auxiliary cover 48 are integrated and the inside is airtight, a sealed circuit breaker can be obtained at low cost. In addition, when the main body cover 45 is made of a soft resin material in this way, even if the cover 45 is made slightly larger than the circuit breaker main body 32, it is easy to cover the circuit breaker main body 32 with the cover 45, and the main body 32, and the circuit breaker main body 32 does not shake inside the cover 45.

Although this invention has been applied to a manual reset type circuit breaker in the above description, it can also be applied to an automatic reset type circuit breaker. In the automatic reset type circuit breaker, for example, parts corresponding to those in FIG. 1 are given the same reference numerals in FIG. It is fixed to the plate 11b side, and the other end is disposed close to and opposite the free end of the bimetal 17. The stopper 56 is biased toward the upper plate 11d, and the screw 5 provided at the reset button position
7, the distance between the bimetal 17 and the end of the stopper 56 is adjusted. After setting this interval, coating 58 is applied to the screw 57 portion with adhesive or the like, and then the main body cover 45 is covered as in the previous case, and furthermore, the auxiliary cover 48 is integrally molded. In this case, the protrusion 47 is not required on the main body cover 45.

In the above, the lead wires 38 and 39 are connected to terminal 1.
The auxiliary cover 48 was integrally formed with these lead wires 38 and 39 connected to the lead wires 38 and 39.
A sealed structure may be provided with the auxiliary cover 48 in a state where the auxiliary cover 48 is not connected. In this case, the protrusions 51 and 52 are omitted, and the terminals 12 and 13 whose peripheries are sufficiently sealed are made to protrude from the auxiliary cover 48.

[Brief explanation of the drawing]

Figure 1 is a front view of an example of a non-sealed manual reset circuit breaker with the front plate removed, Figure 2 is a front view of a conventional sealed circuit breaker, and Figure 3 is based on this invention. A front view showing an example of a sealed circuit breaker, Fig. 4 is a plan view of Fig. 3, and Fig. 5 is a plan view of Fig. 3.
6 is a front view with the front plate removed, showing an example of an automatic reset type circuit breaker. 11: Circuit breaker case, 12, 13: Terminal,
23: Reset button, 32: Circuit breaker, 45:
Main body cover, 47: protrusion, 48: auxiliary cover.

Claims (1)

[Scope of utility model registration request] A terminal is protruded from one side of the circuit breaker body, a lead wire is connected to the terminal, and a main body cover made of a soft resin material is placed over the circuit breaker body except for the side where the terminal protrudes. A cylindrical auxiliary cover made of the same material as the main body cover is formed integrally with the entire circumference of the main body cover to close the opening side of the main body cover protruding from the main body cover, and is integrally formed with the auxiliary cover to surround a part of the above terminals and lead wires. A sealed circuit breaker with a molded protrusion.