JPS6230344B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a non-resetting type safety valve, and particularly aims to provide a safety valve having a simple structure, low cost, and practical configuration.

Conventionally, the valve configuration of a household pressure cooker includes a first control valve such as a weight type or a spring type for controlling the pressure inside the pot at a constant level, and a pressure cooker with a pressure within three times the control pressure by the control valve. The second part operates to release internal pressure.
The Product Safety Act requires that safety valves be installed. As the safety valve, a fusible type is often used, which uses an amorphous alloy such as bismuth that dissolves in a part of the lid of the pressure cooker at a certain temperature to release the internal pressure.

However, the fusible type has a considerable range of operation, and destructive tests had to be conducted to confirm its operation. In particular, when this safety valve is installed in a pressure cooker with relatively low control pressure, it must not operate during normal use, and must operate and release within three times the control pressure, and the allowable operating range is limited to high pressure control. Since the safety valve is relatively small compared to the conventional fusible alloy system, it is impossible to use the conventional fusible alloy method, and there is a need for a safety valve structure that is inexpensive and operates reliably.

In view of the above-mentioned demands, the present invention attempts to securely release and obtain a non-returning state by expanding the operating pressure in two stages during its detection and operation.Examples of the present invention will be described below. will be explained based on the attached drawings.

In the figure, reference numeral 1 designates the lid of the pressure cooker, which has a through hole 1' for installing a safety valve. 2 is the valve case,
Reference numeral 3 indicates an attachment sealant, and 4 indicates a case lid that is screwed into the opening of the valve case 2. The valve case 2 is provided with a valve seat 5' having a valve hole 5 with a diameter A at the bottom, and a mounting flange 6 and a screw are formed above the flange 6 on the outer circumference, and a protrusion on a part of the inner circumference wall. 7 is provided. There is a steam exhaust hole 8 on the case lid 4.
is provided.

On the other hand, a valve body 9 made of a heat-resistant silicone rubber molded body is housed in the valve case 2.
is a valve part 1 that protrudes downward in the center and corresponds to the valve hole 5.
0, a sealing part 11 whose outer periphery is in sliding contact with the valve case 2 and hanging down, and a pressing force part 1 whose upper surface extends against the lower surface of the case lid 4 to apply a downward pressing force F.
Consists of 2.

Incidentally, this pressing force section 12 may be a coil spring 12' as shown in FIG.

Next, the operation in the above configuration will be explained. The pressure inside the pressure cooker covered by the lid 1 is usually controlled to a constant pressure P by a separate pressure regulating valve (not shown).
Suppose that a failure such as a clogging of the pressure regulating valve has led to a point P' at which the safety valve should operate. At this point, the internal pressure applied to the area of the valve hole 5 and the biasing force F are balanced, but if the internal pressure is higher than this, steam will enter the cavity 13 from the valve hole 5. The steam that has entered presses against the seal portion 11 to keep it airtight, so the chamber 13 is quickly filled with steam, and at the same time, this pressure causes an extremely large force corresponding to the diameter B to disrupt the balance with the biasing force F. Then, the valve body 9 rises rapidly. At this time, the presence of the protrusion 7 prevents the valve body 9 from moving in parallel, causing it to fall over and not returning to its original state.

Note that the steam that has reached the empty chamber 14 side is discharged through the steam exhaust hole 8.
more released. After the operation, if necessary, the valve body 9 can be set again to enable reuse.

Further, since the spring 12' shown in FIG. 2 is a separate body, it separates in the event of a fall, and similarly a non-returning state can be obtained.

These configurations show examples of the present invention, and it is easy to change the shape of the case and the form of the protrusion, or to make the pressing force F variable from the outside if necessary. .

As is clear from the above description, according to the present invention, a valve case having a valve hole at the bottom, a case lid detachably attached to the opening of the valve case and having a steam exhaust hole, and an outer peripheral portion. The valve body is integrally formed with a valve portion that slides on the inner wall of the valve case and corresponds to the valve hole, and includes a valve body that moves up and down within the valve case, and a biasing member that presses and biases the valve body downward. Because of the structure, it is possible to operate with high precision that cannot be obtained with fusible alloy type, etc. by simply controlling the pressing force, and once the operation starts, the operating force of the valve body is large due to the action of the empty chamber. As a result, reliable operation can be guaranteed, the number of parts can be reduced with a simple configuration, and the inner peripheral wall of the valve case has a protrusion that restricts the upward movement of the valve body. As a result, when the valve body rises rapidly, the presence of the protrusion prevents the valve body from moving in parallel and overturns, ensuring that the steam in the pot is released from the steam exhaust hole in the case lid. As a result, the pressure inside the pot can be reliably reduced, and since the valve body of this safety valve will not return to its original state if it falls over, it is also possible to check whether the safety valve has operated or not. It is something that can be done easily.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a safety valve showing one embodiment of the present invention, and FIG. 2 is a sectional view of essential parts of a safety valve showing another embodiment of the invention. 2...Valve case, 5...Valve hole, 7...Protrusion,
9... Valve body, 10... Valve part, 11... Seal part,
12...Press biasing section, 12'...Coil spring.

Claims (1)

[Claims] 1. A valve case having a valve hole at the bottom, a case lid detachably attached to the opening of the valve case and having a steam exhaust hole, and a case lid having an outer circumferential portion slidingly in contact with the inner wall of the valve case and corresponding to the valve hole. The valve body is integrally formed with a valve body that moves up and down within the valve case, and a biasing member that presses and biases the valve body downward, and the valve body is attached to the inner circumferential wall of the valve case upwardly. A safety valve with a protrusion that restricts movement.