JPH034087Y2 - - Google Patents

Description

[Detailed description of the invention] [Technical field to which the invention pertains] This invention is a closure system that releases pressure when an abnormality occurs inside a closed electrical device and increases atmospheric pressure, and detects that the pressure has been released. This invention relates to an internal pressure detection device for equipment.

[Prior art and its problems]

When a short circuit or similar accident occurs in closed electrical equipment, the internal temperature becomes high, gas is generated, and the pressure rises. A pressure relief valve body is provided to prevent this increase in atmospheric pressure and release the gas, and a pressure relief detector is further provided to detect when the pressure relief valve body is opened. An example of such a conventional internal pressure release device for a closure device is shown in FIG. In FIG. 3, a rectangular opening 2 is provided on the top surface of a box 1 that houses electrical equipment, a hinge 3 is attached to one side of the outer periphery of this opening 2, and a lid-shaped valve body is attached to the hinge 3. 4 is rotatably attached to cover the opening 2 and can be opened and closed. A pressure release detector 5 is attached to the inner peripheral edge of the opening 2 on the side opposite to the hinge 3. This pressure release detector 5 has a lever 5a, and is configured so that it does not generate a signal when the lever 5a is pressed in a direction perpendicular to its length direction, but generates a signal when the pressure is released; The lever 5a is attached so that it is pressed when the valve body 4 is closed.

When an accident such as a short circuit occurs in the electrical equipment (not shown) housed in the box 1, the temperature becomes high and a gas is generated, the pressure inside the box 1 increases, and this pressure pushes the valve body 4 in the direction of the arrow P. and then pushed open as shown by the dashed line. The gas body whose pressure has increased is released from this opening 2 and is depressurized. Therefore, the lever 5a is released and the pressure release detector 5 issues a signal.

By the way, in such an internal pressure relief device, the valve body 4 is half opened, and even if the lever 5a is once released, the Q
Due to the pressure in the direction of the arrow, the detector 5 is pressed again and has disadvantages such as delaying the operation of the detector 5 and causing chattering. Therefore, as shown in FIG. 4, the valve body 4 is left with the same structure, and the opening 4 on the opposite side of the hinge 3
A small pressing surface that moves lengthwise on the inner periphery of the
For example, it is conceivable to attach a micro switch 6 with a b contact having a push button 6a as a pressure release detector. 7 is a cover of the micro switch 6. However, if the pressure release detector is originally provided inside the box, there is a risk that the detector will be damaged due to high pressure and high temperature, or the insulation of the signal line will be damaged. Originally, in such a device, the valve body is rotatable on a hinge, so it can operate even with a slight increase in pressure, but when this device is attached to the top of the box, the valve body itself falls and presses the pressure release detector again. There is a drawback that it does.

[Purpose of invention]

The present invention aims to eliminate the above-mentioned drawbacks and to provide an internal pressure relief device for a closure device with reliable and accurate operation.

[Key points of the idea]

The present invention provides an internal pressure release device for a closed device that releases abnormal pressure generated inside a sealed box whose opening is closed by a valve body to the outside of the box from the opening. a valve body having a side wall that fits around the outer periphery of the flange, a valve element that extends a mounting part from the side wall and attaches the mounting part to the box body to close the opening; and a valve body that has a push rod. and a pressure release detector that generates a signal when the pressure of the push rod is released, and the pressure release detector is fixed to the box body by pressing the push rod against a side wall opposite to the mounting portion of the valve body. Therefore, the valve body is provided with a flange at the opening, and the directed abnormal pressure bends the valve mounting part and pushes it open, releasing the abnormal gas and preventing the pressure relief valve from automatically returning to its original position. The pressure relief detector was installed outside the box to prevent it from being damaged by the high temperature and pressure inside.

[Example of idea]

An embodiment of the present invention will be described in detail with reference to FIGS. 1 and 2. In FIG. 1, a rectangular opening 2 is provided on the top surface of a box 1 for storing electrical equipment,
A flange 8 is provided around the periphery of this opening 2. The pressure relief valve body 4 has a shallow box shape having a side wall 4a around it, and one side of this side wall extends outward in a right angle direction to form a mounting portion 4b. The valve body 4 surrounds the flange 8 and is placed face down with the bottom facing upward, and the mounting portion 4a is attached to the box body 1 with a holding plate 9 and a set screw 10. A spacing piece 11 is fixed to the side wall 4a on the opposite side of the mounting portion 4b, and the side wall is made thick to ensure the amount of movement of the push rod of the pressure release detector when the valve body 4 is opened. The pressure release detector uses, for example, a micro switch 6 having a b contact,
The box body 1 is covered with a cover 7 for protection, and the push button 6a presses the spacer piece 11.
is attached to.

When electrical equipment (not shown) housed in the box body 1 causes a short circuit or the like, and gas is generated or the temperature rises and the atmospheric pressure rises, the pressure in the direction of the arrow P causes the valve body 4 to curve its mounting portion 4b, as shown by the broken line. It is pushed open and the pressure is released as shown in . At this time, the push button 6a of the micro switch 6 is released as shown in FIG.
The b contact closes and a pressure relief signal is generated by an electric circuit previously connected to the b contact.

[Effect of idea]

As described above, according to the present invention, a flange is provided around the opening of the box body to direct the release of abnormal pressure, and the valve body is provided with a side wall to deepen the valve body inside the box body. It is designed to be able to withstand the pressure of Once the valve body is opened, the mounting portion is curved and does not return to its original position, thereby ensuring reliable operation of the pressure relief detector. Furthermore, since the pressure relief detector is installed outside the box, it is not affected by the internal pressure or altitude, so there is no risk of it being damaged or the insulation of the signal line being torn.

[Brief explanation of drawings]

FIG. 1 is a side sectional view showing an embodiment of the internal pressure release device for a closure device according to the present invention, and FIG.
Fig. 3 is a side sectional view showing an example of a conventional internal pressure release device for a closed device; Fig. 4 is a considered internal pressure release device for a closed device. FIG. DESCRIPTION OF SYMBOLS 1... Box body, 2... Opening, 4... Valve body for pressure relief, 4a... Side wall of the valve body, 4b... Valve body mounting part, 5... Pressure relief detector, 6... Micro switch , 6a...Micro switch push button.

Claims (1)

[Scope of utility model registration request] An internal pressure release device for a closed device that discharges abnormal pressure generated inside a sealed box whose opening is closed by a valve body to the outside of the box from the opening,
A valve body having a flange provided around the opening and a side wall that fits around the outer periphery of the flange, a mounting portion extending from the side wall, and the mounting portion being attached to the box body to close the opening. and a pressure release detector that has a push rod and emits a signal when the pressure of the push rod is released, and the pressure release detector presses the push rod against the side wall opposite to the mounting portion of the valve body and An internal pressure release device for closed equipment, characterized in that it is fixed to a box body.