JPH056465Y2 - - Google Patents

Description

[Detailed Description of the Invention] Purpose of the Invention (Industrial Field of Application) The present invention relates to a fuse mechanism for preventing overflow, and in particular, to a fuse mechanism that maintains a fuse disk that operates in an overflow state in a steady position at normal times. It concerns the shape of a coil spring and its attachment means.

(Prior Art) Regarding the improvement of the coil spring in this type of fuse mechanism for overflow prevention, a device described in Japanese Utility Model Publication No. 10545/1983 has been proposed. FIG. 6 shows its longitudinal cross-sectional view.

In FIG. 6, 51a and 51b are the main body;
2 is a sheet formed on the main body 51b, 53 is a fuse ball, 54 is a holder fixed to the main body 51a, and 55 is one end 56 attached to the holder 54, and the other end 5
7 is a coil spring that is locked to a fuse ball 53.

Note that FIG. 7 is a perspective view showing the holder 54. As shown in FIG.

As shown in FIG. 6 above, one end 56 of the coil spring 55 is engaged with a cutout recess 59 formed in the bottom protrusion 58 of the holder 54, and the other end of the coil spring 55 57 is externally fitted and fixed in an annular groove 60 formed on the upstream side of the fuse ball 53 with the opening direction facing outward in the diametrical direction. Moreover, the coil spring 5 is locked or externally fitted.
Both one end 56 and the other end 57 of 5 are reduced in diameter to fit into the cutout recess 59 or the groove 60.

(Problem to be solved by the invention) In this structure, when the one end 56 of the coil spring 55 is locked in the notch recess 59, the other end 56
7 into the groove 60, it is necessary to expand the diameter of the one end 56 and the other end 57, and at this time, the one end 56 and the other end 57 undergo diameter expansion deformation.
The locking and external fitting become uncertain, and there is a risk that the one end 56 may come off from the notch recess 59 or the other end 57 from the recessed groove 60 during use.

Further, when the fuse ball 53 moves in the direction of the seat 52 due to the flow of fluid at the time of excessive flow and stretches the coil spring 55, furthermore, when such extension and restoration of the coil spring 55 are repeated, There is a possibility that one end 56 or the other end 57 of the coil spring 55 expands in diameter and separates from the notch recess 59 or the groove 60.

Furthermore, in a ball valve or cockpit with a built-in fuse mechanism, when fluid overflows, the fuse ball 53 is pushed by the fluid and presses against the seat 52, remaining in the closed state.
3 may not easily return to the steady state.

The present invention provides a fuse mechanism for overflow prevention having a coil spring for holding a fuse ball (fuse disc in the present invention) in a steady position during normal operation, in which one end is attached to a fixed part of the fuse mechanism.
In addition, when a coil spring whose other end is fixed to a fuse ball expands in diameter when one end or the other end is detached during use, or if the coil spring expands,
Or when the coil spring is repeatedly expanded and restored,
This is an attempt to solve the above-mentioned problem of one end or the other end separating from the fixed part of the fuse mechanism or the fuse ball.

Furthermore, when the fuse mechanism is activated in ball valves and cockpits that have a built-in fuse mechanism,
This is intended to solve the problem that the fuse ball remains in a closed state where it is pressed against the seat and does not return to a steady state.

Structure of the invention (Means for solving the problem) The present invention has solved the above problem by the following means.

That is, the present invention is a fuse mechanism that shuts off gas when an excessive flow rate of gas flows.
A coil spring that holds the fuse disc provided at the tip of the cylindrical holder in a steady position during normal operation is housed between the holders, and this coil spring is closely wound around one end to a diameter larger than the winding diameter of the spring portion of the coil spring. The large-diameter mounting part is formed at the other end with a small-diameter mounting part tightly wound to a diameter smaller than the winding diameter of the spring part, and the large-diameter mounting part is an annular protruding step part provided on the inner peripheral surface of the upstream tube part of the holder. and the small diameter attachment portion was locked to the fuse disk.

Further, a headed pin having a head that fits loosely inside the spring portion of the coil spring and a shaft portion that loosely fits inside the small diameter attachment portion is inserted into the coil spring from the large diameter attachment portion side. However, it is preferable that the head part supports the small diameter attachment part and that the shaft part is locked to the upstream central part of the fuse disk.

Furthermore, such a fuse mechanism is built into the flow path on the upstream or downstream side of the valve or valve.

Furthermore, a ball valve or valve having such a fuse mechanism built into the upstream flow path,
When closing the ball valve or cock,
The closing member of the ball valve or the lock comes into contact with the fuse disc to release the closed state of the fuse disc.

(Operation) The fuse mechanism of the present invention and the valve and cock incorporating this fuse mechanism operate as follows.

First, in the fuse mechanism of the present invention, one end of the coil spring is a large-diameter attachment part tightly wound to a diameter larger than the winding diameter of the spring part, so there is an annular step protruding inward at the fixed part of the fuse mechanism. By providing a section or the like, one end can be easily and reliably locked. In addition, since the other end of the coil spring is a small-diameter mounting part that is tightly wound to a diameter smaller than the winding diameter of the spring part, the head part fits loosely inside the spring part and the shaft fits loosely inside the small-diameter mounting part. The other end can be easily and reliably locked to the upstream central part of the fuse disc using a headed pin such as a headed bolt or headed snap pin having a section.

Therefore, when the coil spring is attached to the fuse mechanism of the present invention, the coil spring will not be deformed, and therefore, one end or the other end will not come off during use.

Furthermore, even if the fuse mechanism is operated and the coil spring is expanded, or the expansion and restoration are repeated, one end and the other end will not be deformed and will not come off.

Next, in a ball valve or cock with a built-in fuse mechanism, even if the fuse disc activated due to overflow presses against the seat and remains closed, when the ball valve or cock is operated to close, the ball valve or The closing member of the lock comes into contact with the fuse disc and separates the fuse disc from the seat, releasing the closed state, so that the fuse disc returns to its normal position by the force of the coil spring.

(Example) Hereinafter, an example of the present invention will be described based on FIGS. 1 to 5.

First, FIG. 1 is a longitudinal sectional view showing one embodiment of the fuse mechanism of the present invention.

In Fig. 1, 1 is a fuse mechanism that shuts off the gas when an excessive flow rate of gas flows, 2 is the main body, 3 is the fuse disc, 4 is a coil spring, and 5
is a holder.

FIG. 2 is a half-cut perspective view of the holder 5 shown in FIG. ing. Further, as shown in FIG. 1, a passage 7 divided by a rib 6 is formed between the main body 2 and the holder 5, and gas flows through this passage 7 during normal operation. Further, a through hole 8 is formed in the center of the holder 5, and an annular protruding step portion 10 is provided on the inner circumferential surface 9 of the upstream tube portion of the through hole 8. Further, on the downstream side of the holder 5, an annular flat surface 11 perpendicular to the through hole 8 is formed.

The coil spring 4 includes a spring portion 12 , a large-diameter mounting portion 14 tightly wound at one end 13 to a diameter larger than the winding diameter of the spring portion 12 , and a large-diameter mounting portion 14 tightly wound at the other end 15 to a diameter smaller than the winding diameter of the spring portion 12 . The coil spring 4 is inserted into the holder 5 from the upstream side as shown in FIG.
is locked to the annular protruding step portion 10.

The fuse disk 3 has a hemispherical bowl shape, and a columnar projection 17 is formed at the upstream side, that is, at the center of the inside of the hemispherical bowl shape, and a mounting hole 19 for mounting a snap pin 18 is formed at the center of the columnar projection 17. .

The snap pin 18 is a headed pin having a head 20 that fits loosely inside the spring portion 12 and a shaft portion 21 that fits loosely inside the small diameter attachment portion 16. , is inserted from the large diameter attachment part 14 side, the head 20 obstructs the small diameter attachment part 16, and the shaft part 21 is installed and locked in the attachment hole 19.

Further, the edge of the fuse disk 3 is a contact annular surface 22 having a flat annular shape, and the contact annular surface 22 is in contact with the annular plane 11 due to the contractile force of the coil spring 4, and this state is constant. This is a steady state at all times.

Note that 23 is a sheet formed on the main body 2, and when the gas overflows, the pressure of the gas flowing through the through hole 8 of the holder 5 causes the fuse disc 3 to move downstream, press the sheet 23, and release the gas. to cut off the flow of water.

Next, FIG. 3 is a longitudinal sectional view showing a ball valve which is an embodiment of the valve or valve incorporating the fuse mechanism of the present invention.

In FIG. 3, 1 is a fuse mechanism,
The symbols attached to the parts and parts constituting the fuse mechanism 1 and their structures are the same as those described in FIGS. 1 and 2.

In FIG. 3, 31 is a ball valve, 32 is a valve body, 33 is a ball which is a closing member of the ball valve 31, 34 is a ball seat, 35 is a stem, 36 is a handle, 37 is an insert, and the fuse mechanism 1 is built into the upstream flow path of the valve body 32 and fixed with an insert 37.

In the ball valve 31, the handle 3
6 is rotated approximately 90 degrees to rotate the ball 33 via the stem 35 to perform a valve opening or closing operation. FIG. 3 shows the valve in an open state, and gas flows in this state during normal operation.

When an excessive amount of gas flows, as explained with reference to FIG. Cut off the gas flow. FIG. 4 is a partial vertical sectional view showing this state.

When the ball valve 31 is closed in this state, the rotating ball 33 comes into contact with the fuse disc 3. FIG. 5 is a partial cross-sectional view showing this state. When the ball 33 is further turned in the valve-closing direction (in the direction of the arrow in the figure), the ball 33 pushes the fuse disc 3 to the left in the figure and separates it from the seat 23. , release the closed state.

Next, the operation of the embodiment shown in FIGS. 1 to 5 will be explained.

First, in FIG. 1, one end 13 of the coil spring 4 is a large-diameter mounting portion 14 tightly wound to a diameter larger than the winding diameter of the spring portion 12.
One end 13 of the spring 4 can be easily and reliably locked by the annular protruding step 10.

Further, the other end portion 15 of the coil spring 4 is connected to the spring portion 12.
Small-diameter attachment part 16 tightly wound to a diameter smaller than the winding diameter of
Therefore, a headed snap pin 18 having a head 20 that fits loosely inside the spring portion 12 and a shaft portion 21 that fits loosely inside the small diameter attachment portion 16 is formed on the columnar projection 17 of the fuse disk 3. Mounting hole 1
9, the other end 15 of the coil spring 4 can be easily and reliably locked.

For this reason, when the coil spring 4 is attached to the fuse mechanism 1, the coil spring 4 is not deformed, and therefore the one end 13 or the other end 15 is not deformed during use.
never leaves.

Furthermore, the fuse mechanism 1 operates and the coil spring 4
Even if it is expanded or the expansion and restoration are repeated, the one end 13 and the other end 15 will not be deformed and will not come off.

Next, in the ball valve 31 with the built-in fuse mechanism 1 shown in FIG. 3, even if the fuse disc 3 activated due to overflow presses against the seat 23 and is in the closed state, if the ball valve 31 is operated to close. , the ball 33, which is the closing member of the ball valve 31, comes into contact with the fuse disc 3 and separates the fuse disc 3 from the seat 23, releasing the closed state.
It returns to its normal position by the force of .

Although the embodiment shown in FIG. 3 is a ball valve, it goes without saying that a ball valve or other valve can be constructed and operated in the same manner.

Effects of the Invention As is clear from the above, the fuse mechanism of the present invention and the valve or pot incorporating this mechanism provide the following excellent effects.

(1) The coil spring that holds the fuse disk in a steady position during normal operation can be easily and reliably attached to the fuse mechanism.

(2) Since the mounting portion of the coil spring does not deform when the coil spring is attached to the fuse mechanism, the coil spring will not come off when the fuse mechanism is activated or repeatedly activated.

(3) When the fuse mechanism is activated or repeatedly activated, the coil spring mounting part will not deform and the coil spring will not come off.

(4) For valves or locks with a built-in fuse mechanism, the fuse disk, which is closed due to excessive gas outflow, can be easily and reliably maintained by closing the closing member of the valve or lock. It can be returned to position.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view showing one embodiment of the fuse mechanism of the present invention, Fig. 2 is a half-cut sectional view of the holder in Fig. 1, and Fig. 3 is a view of a valve or a pot incorporating the fuse mechanism of the present invention. A vertical cross-sectional view of a ball valve showing an example, FIG. 4 is a partial vertical cross-sectional view showing the ball valve shown in FIG. 3 in a state in which the fuse disk is pressed against the seat, and FIG. 5 is a valve closing operation from the state shown in FIG. 4. FIG. 6 is a longitudinal sectional view showing a conventional example of the fuse mechanism, and FIG. 7 is a perspective view showing the holder in FIG. 6. 1...Fuse mechanism, 3...Fuse disc,
4...Coil spring, 5...Holder, 9...Inner surface of the upstream tube section, 10...Annular protruding step, 12...
Spring part, 13... One end part, 14... Large diameter mounting part,
15...Other end, 16...Small diameter mounting part, 18...
Snap pin (headed pin), 20...Head, 2
1... Shaft portion, 31... Ball valve, 32... Ball (closing member).

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A fuse mechanism that shuts off gas when an excessive flow of gas flows, and a coil spring that maintains a fuse disk provided at the tip of a cylindrical holder in a steady position during normal operation. is stored between the holders,
This coil spring has a large diameter mounting part tightly wound at one end to a diameter larger than the winding diameter of the spring part of the coil spring, and a small diameter mounting part tightly wound to a diameter smaller than the winding diameter of the spring part at the other end. A fuse mechanism characterized in that the large-diameter mounting portion is supported by an annular protruding step provided on the inner peripheral surface of the upstream tube portion of the holder, and the small-diameter mounting portion is locked to the fuse disc. (2) A headed pin having a head that fits loosely inside the spring portion of the coil spring and a shaft portion that fits loosely inside the small diameter attachment portion is attached to the coil spring from the large diameter attachment portion side. 2. The fuse mechanism according to claim 1, wherein the fuse disk is inserted into the fuse disk, the small-diameter attachment portion is supported by the head portion, and the shaft portion is locked to the upstream central portion of the fuse disk.