AU669626B2 - Safety device for a valve - Google Patents

Description

L R/UUIU11 2B/5/91 Regulation 3.2(2)

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT o 4

C.,

94#:

A

4%t Application Number: Lodged: Invention Title: SAFETY DEVICE FOR A VALVE i The following statement is a full description of this invention, including the best method of performing it known to us i

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1 2 4 6 7 8 9 14 6 21 22 23 24 26 27 28 29 29 SAFETY DEVICE FOR A VALVE BACKGROUND OF INVENTION The present invention relates to a valve for gas. The present invention particularly relates to a safety device for a valve. The safety device will automatically seal the valve when temperature near the valve increases as a result of flames.

Gas is a convenient fuel to provide heat for people.

On the other hand, gas is a dangerous fuel in comparison to coal and wood. This is the reason why various devices have been devised in order to safely transmit and burn gas.

Nevertheless, disasters still often occur as a result of leakage of gas, although devices for transmitting gas and devices for burning gas have improved safety. People are taught to close valves for gas when undesired flames occur.

However, it is often too dangerous and difficult for people to close valves when undesired flames actually occur.

Therefore, there is a long and unfulfilled need for a safety, device for a valve. The safety device will automatically seal the valve when temperature near the valve increases as a result of flames.

SUMMARY OF INVENTION It is the primary object of the present invention to provide safety for a valve. The safety device will automatically seal the valve when temperature near the valve increases as a result of flames.

The primary object of the present invention is achieved by providing a safety device which is received in an outlet i I ~I I 1 of a valve. The safety device will automatically seal the 2 outlet of the valve when flames occur near the valve. The 3 safety device includes a spring, a sleeve, a collar and a 4 low-melting-point plastic sleeve. The spring is received in.

the outlet of the valve. The sleeve is received in the 6 outlet of the valve, and includes a closed end which abuts 7 against the spring and an open end. The sleeve defines an 8 aperture near the closed end thereof. The collar is 9 received in the outlet of the valve, and is mounted on the 1 sleeve. The low-melting-point plastic sleeve is received in the outlet of the valve, and abuts against the sleeve in order to push the aperture beyond the collar. The spring 1'3" biases the sleeve further into the collar so that the 14 aperture which is defined in the sleeve is sealed by the collar when the low-melting-point plastic sleeve is melted 16 as flames occur near the valve.

In another aspect of the present invention, the sleeve 1" 4 includes a disk which is formed on the closed end of the sleeve. An annular pa-king is attached to an end of the 000 0 collar. The disk can abut against the annular packiig in 21 order to block gas between the collar and the sleeve.so as 22 to further ensure the sealing effect of the safety device.

23 For a better understanding of the present invention and 24 objects thereof, a study of the detailed description of the embodiments described hereinafter should be made in relation 26 to the accompanying drawings.

27 BRIEF DESCRIPTION OF DRAWINGS 28 Figure 1 is a cross-sectional view of a valve which 29 2 1 employs a safety device in accordance with the preferred 2 embodiment of the present invention, showing that the valve 3 co-operates with a joint which employs a flow-controlling 4 device in accordance with a co-pending patent application by the present inventor; 6 Figura 2 is an enlarged cross-sectional view of the 7 joint and the flow-controlling device shown in Figure 1; 8 Figure 3 is a similar view to Figure 1, but showing 9 that the safety device seals the valve; and 1.0° Figure 4 is a similar view to Figure 1, but showing a a that the flow-controlling device seals the joint.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT '13 Referring to Figure 1, a valve uses a valve housing 14 transversely from which a tubular section 34 projects. The tubular section 34 is configured in order to receive a '16 safety device and a flow-controlling device. The remaining portion of the valve will not be described in detail as it is well known.

;19p. The tubular section 34 defines an internal surface. A thread 35 is formed on a portion of the internal surface of 21 the tubular section 34. The internal surface of the tubular 22 section 34 includes a stepped configuration so as to form a 23 shoulder 36 at an upstream position and a shoulder 38 at a 24 downstream position.

A spring 33 is received in the tubular section 34 in a 26 way that the spring 33 is disposed against the shoulder'36.

27 A sleeve 40 includes a closed end and an open end. A disk 28 42 is formed at the closed end of the sleeve 40. The sleeve 29 3 I (1 t! 1 40 defines, near the disk 42, an aperture 44. The sleeve 2 is received in the tubular section 34 in a way that the disk 3 42 io disposed against the spring 33.

4 A collar 31 includes an external surface and an internal surface. The collar 31 includes a first section 6 and a second section in an axial arrangement. The first 7 section of the collar 31 axially defines a shallow recess in 8 order to receive an annular packing 37. The external 9 surface of the first section of the collar 31 defines an annular slot in order to receive a sealing ring 39. A I thread 32 is formed on the external surfaze of the second 1-2' section of the collar 31. The thread 32 is engageable with i the thread 35 so that the collar 31 is receivable in the 14 tubular section 34. The collar 31 is mounted on the sleeve 40. The annular packing 37 prevents gas from flowing 16 between the internal surface of the collar 31 and the external surface of the sleeve 40. The sealing ring 39 1'8' prevents gas from flowing between the external surface of 8 the collar 31 and the internal surface of the tubular S(4 t section 34.

21 A sealing collar 46 includes an external surface and an 22 internal surface. The sealing.collar 46 includes a first 23 section and a second section in an axial arrangement. The 24 sealing collar 46 is received in the tubular section 34 so that the first section of the sealing collar 46 .s received 26 in the second section of the collar 31. The internal 27 surface of the first section of the sealing collar 46 is 28 cylindrical. The internal surface of the second section of 29 c Fc:-

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rl 1 2 3 4 6 7 8 9 o o 0 0 0 13 14 s. 16 .600 18 Q 2 0 21 22 23 24 26 27 28 the sealing collar 46 is frustum-conical.

Referring to Figures 1 and 2, a joint 10 is a hollow member which includes a first end on which a large head 14 is f--ed and a second end on which a thread 11 is formed.

The h zd 14 includes a frustum-conical external surface which defines an annular slot (not numbered) in order to receive a sealing ring 15. The head 14 is received in the tubular section 34 in a way that the frustum-conical surface of the head 14 engages with the frustum-conical surface of the collar 46. The thread 11 is engageable with a thread which is formed on an internal surface of a pipe which leads to a burner (not shown).

A joint-retaining collar 16 includes an external surface on which a thread 17 is formed. The thread 17 is engageable with the thread 35 so that the joint-retaining collar 16 is receivable in the tubular section 34 in a way that the head 14 is pressed by an end of the joint-retaining collar 16, Thus, the joint 10 is retained to the tubular section 34.

A low-melting-point plastic sleeve 13 is received in the head 14. The low-melting-point plastic sleeve 13 is abutted against a flow-controlling device 20 which is disposed against a shoulder 18 which is formed on an internal surface of the joint The flow-controlling device 20 includes a sleeve 21 and a sleeve 22. The.sleeve 21 includes a first end and a second end. The sleeve 22 includes a first end and a second end. The first end of the sleeve 21 is received in the .i 1 second end of the sleeve 22 so as to form a hous,_ng 26. A 2 spring 23 and a peg 24, from which a protrusion 25 projects, 3 are received in the housing 26 in a way that the spring 23 4 biases the peg 24 away from the first end of the sleeve 22.

An end of the spring 23 is mounted on the protrusion 6 The second end of the sleeve 21 defines an aperture 26. The 7 first end of the sleeve 22 defines an aperture 27.

8 When the valve is in a position shown in Figure 1, the oo .09 collar 16 retains the joint 10 to the tubular section 34.

Si 0 The shoulder 18 abuts against the flow-controlling device oi 20. The flow-controlling device 20 abuts against the lowmelting-point plastic sleeve 13. The low-melting-point 13 plastic sleeve 13 abuts against the sleeve 40 so that the aperture 44 is disposed beyond the collar 31, the %15 aperture 44 is not sealed by the collar 31. The disk 42 :6 compresses the spring 33. Thus, gas is allowed to flow t through the aperture A4 into the sleeve t 18 Gas is allowed to further flow through the low-meltings "'1i point plastic sleeve 13. A force which results from the 3: 20 difference (6P) between the pressure of gas in a gas source i, 21 (P1) and the pressure of gas in the burner (P2) overcomes a 22 force from the spring 23 so that gas pushes the peg 24 away -a 23 from the first end of the sleeve 22 so as to allow gas to 24 flow through the aperture 27 into the housing 26. If there 2 25 is not any leakage of gas from the pipe which leads to the 26 burner, 6P will be retained below a certain value, the 27 force which.results from 6P is not sufficient to push the 28 peg 24 against the first end of the sleeve 21. That is, gas 29 J6 1 is allowed to flow into the sleeve 21. Gas will further 2 flow through the aperture 26, the joint 10 and the pipe to 3 the burner.

4 Referring to.Figure 3, if there is leakage of gas from the pipe, 6P will exceed the certain value, the force 6 which results from 6P is sufficient to push the disk against 7 the first end of the sleeve 21. Thus, the sleeve 21 is 8 sealed, gas is blocked by the flow-controlling device 9 i0 Referring to Figure 4, the low-melting-point plastic sleeve 13 will be melted if flames occur near the valve.

The spring 33 biases the sleeve 40 further into the collar 31 so that the aperture 44 is sealed by the collar 31, i.e., 14 the valve is closed. Furthermore, the disk 42 abuts against the annular packing 37 in order to block gas between the internal? surface of the collar 31 and the external surface 17". of the sleeve 40. The spring 33 cannot push the sleeve out of the collar 31 because of the disk 42.

19.. While the present invention includes been explained in relation to its preferred embodiment, it is to be understood 21 that variations thereof will be apparent to those skilled in 22 the art upon reading this spei'fication. Therefore, the 23 present invention is intend, to cover all.such variations 24 as shall fall within the scope of the appended claims.

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Claims (3)

1. A safety device which is received in an outlet of a valve in order to seal the outlet of the valve when flames occur near the valve, wherein the safety device comprises: a spring which is received in the outlet of the valve; a sleeve which is received in the outlet of the valve, and which comprises a closed end which abuts against the spring and an open end, and which defines an aperture near the closed end thereof; a collar which is received in the outlet of the valve, and is mounted on the sleeve; and a low-melting-point plastic sleeve which is received in the outlet of the valve, and which abuts against the sleeve in order to push the aperture beyond the collar; whereby the spring biases the sleeve further into the collar so that the aperture which is defined in the sleeve is sealed by the collar when the lo--melting-point plastic sleeve is melted as flames occur near the valve.

2. A safety device in accordance with claim 1 wherein the sleeve comprises a disk which is formed on the closed end of the sleeve.

3. A safety device in accordance with claim 2 comprising an annular packing which is attached to an end of the collar, whereby the disk can abut against the annular packing in order to block gas between the collar and the sleeve so as to further ensure the sealing effect of the safety device. DATED this 15th day of June 1994, FOCUS LIFESTYLE PRODUCTS PTY. LTD. WATERMARK PATENTS TRADEMARK ATTORNEYS "THE ATRIUM" 290 BURWOOD ROAD, HAWTHORN. VIC. 3122. r .r i i; 1 ABSTRACT OF DISCLOSURE 2 A safety device is received in the outlet of a valve in 3 order to seal the outlet of the valve when flames occur near 4 the valve. The safety device includes a spring, a sleeve, a collar and a low-melting-point plastic sleeve. The spring 6 is received in the outlet of the valve. The sleeve is 7 received in the outlet of the valve, and includes a closed 8 end which abuts against the springand an open end. The 9 sleeve defines an aperture near the closed end thereof. The collar is received in the outlet of the valve, and is 11 mounted on the sleeve. The low-melting-point plastic sleeve 12 is received in the outlet of the valve, and abuts against 13 the sleeve in order to push the aperture beyond the collar. ooo 0o o The spring biases the sleeve further into the collar so that o o I the aperture which is defined in the sleeve is sealed by the *Ifo' collar when the low-melting-point plastic sleeve is melted o o 17 as flames occur near the valve. 18 o S19 0. 6 S *C °S4 26 27 28 29 I