Valve assembly for a gas-heatable appliance for personal use

Abstract

A gas-heatable appliance for personal use receives an inflammable gas reservoir and comprises a combustion chamber and a valve assembly mounted between the inflammable gas reservoir and the combustion chamber. The valve assembly comprises a valve housing defining a gas passageway, a sealing member mounted in the gas passageway and movable between a first position allowing flow of the inflammable gas and a second position blocking the gas passageway, a movable member mounted in the gas passageway in a position other than the sealing member, and a temperature-responsive member disposed in the valve housing. The movable member is movable by the temperature-responsive member in response to a temperature of the combustion chamber to thereby vary an area of cross section permitting gas flow.

Description

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a valve assembly for a gas-heatable appliance for personal use.

[0003] 2. Description of the Related Art

[0004] Gas-heatable appliances for personal use are well known in the art. U.S. Pat. No. 5,800,154 to Henninger et al. issued on Sep. 1, 1998 discloses a gas heatable appliance for personal use. The gas heatable appliance comprises a valve assembly disposed between the fuel gas reservoir and the combustion chamber for controlling and/or regulating the amount of fuel gas supplied, in particular in dependence upon temperature. The valve assembly comprises a temperature-responsive actuator to detect the temperature in the combustion chamber. The temperature-responsive actuator comprises a rod having a tip to actuate an elastic tongue of a sealing element, thereby varying the area of cross section permitting the flow of gas in the passageway. However, the elastic tongue is merely connected to the sealing element by a small portion; namely, most part of the elastic tongue is not in contact with the sealing element and thus tends to fatigue after a term of use. As a result, the elastic tongue cannot provide the required regulation. Further, the temperature-responsive actuator is apt to malfunction, as it is exposed to high heat. As a result, the displacement of the elastic tongue of the sealing element is no longer accurate, which leads to unstable gas flow.

SUMMARY OF THE INVENTION

[0005] An object of the present invention is to provide a valve assembly for a gas-heatable appliance for personal use, wherein a stable regulation of gas flow is obtained by means of providing a movable member that is actuatable by a temperature-sensitive member and that is separate from a sealing member.

[0006] Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] FIG. 1A is a plan view of a gas-heatable appliance for personal use in accordance with the present invention.

[0008] FIG. 1B is a plan view, partially sectioned, of the gas-heatable appliance for personal use in accordance with the present invention.

[0009] FIG. 2 is a perspective view of a valve assembly of the gas-heatable appliance for personal use in accordance with the present invention.

[0010] FIG. 3 is an exploded perspective view of the valve assembly.

[0011] FIG. 4 is a sectional view taken along plane 4-4 in FIG. 2.

[0012] FIG. 5 is a perspective view, partly cutaway, of the valve assembly.

[0013] FIG. 6 is a sectional view taken along plane 6-6 in FIG. 2.

[0014] FIG. 7 is a view similar to FIG. 4, wherein the switch is in an on position.

[0015] FIG. 8 is a sectional view, taken along plane 8-8 in FIG. 7.

[0016] FIG. 9 is a perspective view, partly cutaway, of the valve assembly, wherein the switch is in the on position.

[0017] FIG. 10 is a sectional view taken along plane 10-10 in FIG. 8.

[0018] FIG. 11 is an exploded perspective view illustrating a modified embodiment of the valve assembly in accordance with the present invention.

[0019] FIG. 12 is a sectional view of the valve assembly in FIG. 11.

[0020] FIG. 13 is a sectional view similar to FIG. 12, illustrating gas flow in the valve assembly.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0021] Referring to FIGS. 1A and 1B, a gas-heatable appliance 10 for personal use in accordance with the present invention generally comprises a first end 11 and a second end 12. A heating means (not shown) having a combustion chamber (not shown) is mounted in the first end 11 of the gas-heatable appliance 10. The heating means is capable of generating sufficient heat that can be transmitted to the outside. An inflammable gas reservoir (not shown) is mounted in the second end 12 of the gas-heatable appliance 10 for supplying inflammable gas to the combustion chamber. A valve assembly 20 is mounted between the inflammable gas reservoir and the combustion chamber and controlled by a switch 13 to regulate the flow of the inflammable gas.

[0022] Referring to FIGS. 2 through 4, the valve assembly 20 comprises an upper seat 30, a lower seat 40, a sealing member 50 between the upper seat 30 and the lower seat 40, a temperature-control means 60, and a passage control means 70. The upper seat 30 comprises a first face 31 and a second face 32 opposite to the first face 31. Two stepped holes 33 and 34 and a screw hole 35 extend from the first face 31 through the second face 32. The stepped hole 33 comprises a relatively larger threaded section 331 having an outer end in the second face 32 of the upper seat 30. The stepped hole 33 further comprises a relatively smaller section 332 having an outer end in the first face 31 of the upper seat 30. Similarly, the stepped hole 34 comprises a relatively larger threaded section 342 having an outer end in the first face 31 of the upper seat 30 and a relatively smaller section 341 having an outer end in the second face 32 of the upper seat 30. A passageway 343 is defined in the second face 32 of the upper seat 30 and communicated with the relatively smaller section 341 of the stepped hole 34. An outlet tube 37 has a threaded section (not labeled) for threadedly engaging with the screw hole 35. The outlet tube 37 further has a longitudinal passage 371.

[0023] The lower seat 40 comprises a first face 41 and a second face 42 opposite to the first face 41. The lower seat 40 further comprises a stepped hole 43 extending from the first face 41 through the second face 42. The stepped hole 43 has a ledge 431 (FIG. 6). A regulating member 48 is mounted in the stepped hole 43 and rests on the ledge 431. Nevertheless, in an alternative embodiment, the regulating member 48 is integrally formed with the lower seat 40. The regulating member 48 comprises a conic hole 481 for receiving a movable member 483. In this embodiment, the movable member 483 is a ball that may move relative to the regulating member 48, and an elastic member 484 is mounted to support the ball 483. The regulating member 48 further comprises a port 482 that is communicated with the conic hole 481. The inflammable gas from the inflammable gas reservoir directly enters the port 482. A passageway 44 is defined in the first face 41 of the lower seat 40 and communicated with the screw hole 35 of the upper seat 30. Further, a passageway 45 is defined in the first face 41 of the lower seat 40 and communicated with the passage 343 of the upper seat 30. Also defined in the first face 41 of the lower seat 40 is an engaging slot 46 that intercommunicates the passageway 44 with the passageway 45, best shown in FIG. 3. Bolts 38 are extended through screw holes 36 in the upper seat 30 and screw holes 47 in the lower seat 40 to thereby secure the upper seat 30 and the lower seat 40 together. Thus, the upper seat 30 and the lower seat 40 together form a valve housing defining a passageway for the inflammable gas.

[0024] The sealing member 50 is preferably a resilient sheet made of metal and sandwiched between the second face 32 of the upper seat 30 and the first face 41 of the lower seat 40. Holes 54 are defined in the sealing member 50 and extended through by the bolts 38. The sealing member 50 further comprises a hole 51 for intercommunicating the screw hole 35 of the upper seat 30 with the passageway 44 of the lower seat 40, a hole 52 for intercommunicating the passageway 341 of the upper seat 30 with the passageway 45 of the lower seat 40, and a hole 53 for intercommunicating the screw hole 34 of the upper seat 30 with the hole 43 of the lower seat 40.

[0025] The temperature-control means 60 comprises a base 61 (in the form of a rod in this embodiment) and a temperature-responsive member 62. The base 61 comprises a threaded end 611 threadedly engaged in the relatively larger threaded section 342 of the stepped hole 34 of the upper seat 30. An O-ring 612 is mounted around the threaded end 611 of the base 62 in the relatively larger threaded section 342 of the stepped hole 34 to prevent leakage. The temperature-responsive member 62 is mounted in a longitudinal hole 613 of the base 61 for detecting the temperature in the combustion chamber and thus moving longitudinally relative to the base 61. The movable member 483 may be integrally formed with an end of the temperature-responsive member 62.

[0026] The passage control means 70 comprises an engaging member 71, an elastic member 72, and a control member 73. The engaging member 71 is mounted in the stepped hole 33 of the upper seat 30 and comprises a neck 711 in an end thereof that extends beyond the first face 31 of the upper seat 30. A flange 712 is formed on the other end of the engaging member 71. The elastic member 72 is mounted around the engaging member 71 with two ends of the elastic member 72 attached to the flange 712 of the engaging member 71 and a shoulder 333 of the stepped hole 33, best shown in FIG. 4. The control member 73 comprises an engaging slot 732 in an end thereof, the engaging slot 732 and having an enlarged end 731 to allow insertion of the end of the engaging member 71, and the engaging member 71 is moved away from the enlarged end 731 of the engaging slot 732 until the neck 711 of the engaging member 71 is engaged in the engaging slot 732. Thus, the control member 73 may be moved to cause longitudinal movement of the control member 71 relative to the upper seat 30.

[0027] When the switch 13 is in an off position shown in FIG. 4, the control member 73 is located on a lower end of the switch 13 and thus not actuated. In this case, the flange 712 of the engaging member 71 is biased by the elastic member 72 to press against the sealing member 50. The sealing member 50 deforms and thus blocks the engaging slot 46 in the lower seat 40. As illustrated in FIG. 5, the inflammable gas from the inflammable gas reservoir flows through the port 482 and the conic opening 481 of the regulating member 48, the hole 53 of the sealing member 50, the passageway 343 of the upper seat 30, and the passageway 45 of the lower seat 40. However, since the engaging slot 46 of the lower seat 40 is blocked by the sealing member 50, the inflammable gas cannot enter the passageway 44. As illustrated in FIG. 6, the movable member 483 in the conic hole 481 of the regulating member 48 is retained in place by the temperature-responsive member 62 of the temperature-control means 60.

[0028] Referring to FIGS. 7 and 8, when the switch 13 is moved to its on position to ignite the inflammable gas, the control member 73 of the passage control means 70 is located at an upper end of the switch 13 such that the control member 73 pivots relative to the upper seat 30. The engaging member 71 is moved upward and the flange 712 of the engaging member 71 leaves the sealing member 50. The sealing member 50 is resilient and thus restores its original shape; namely, the sealing member 50 is disengaged from the engaging slot 46 of the lower seat 40. Referring to FIG. 9, the inflammable gas in the passageway 45 flows through the engaging slot 46 and the passageway 44 and finally enters the combustion chamber via the longitudinal passage 371 of the outlet tube 37. Referring to FIG. 10, the temperature-responsive member 62 of the temperature-control means 60 detects the temperature in the combustion chamber and moves longitudinally relative to the base 10 in response the detected temperature, thereby slightly moving the movable member 483 in the conic hole 481 of the regulating member 48. Thus, the movable member 483 in the conic hole 481 of the regulating member 48 is slightly moved upward or downward in response to the temperature of the combustion chamber, thereby varying the area of cross section permitting the gas flow. When the pressure of the inflammable gas is insufficient to move the movable member 483 upward, the elastic member 484 biases the movable member 483 away from the port 481 and thus assists in upward movement of the movable member 483 as a result of the longitudinal movement of the temperature-responsive member 62 in response to a change in the temperature of the combustion chamber.

[0029] FIG. 11 illustrates a modified embodiment of the invention, wherein the ball 483 is replaced by a movable member 484 having a conic portion 485 that has a tapering direction the same as that of the conic hole 481 of the regulating member 48. FIGS. 12 and 13 illustrates operation of the modified embodiment of the invention, which is identical to that of the above-mentioned embodiment.

[0030] According to the above description, it is appreciated that the sealing member 50 does not participate in the regulation of the gas flow. Instead, it is achieved by the temperature-responsive member 62 and the movable member 483, 484 that is separate from the sealing member 50. Thus, the inaccurate regulation in prior art is avoided.

[0031] Although the invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the scope of the invention as hereinafter claimed.

Claims

1. A gas-heatable appliance for personal use adapted to receive an inflammable gas reservoir and comprising a combustion chamber and a valve assembly mounted between the inflammable gas reservoir and the combustion chamber for regulating a flow of inflammable gas supplied in response to the temperature of the combustion chamber, the valve assembly comprising: a valve housing defining a gas passageway; a sealing member mounted in the gas passageway and movable between a first position allowing flow of the inflammable gas and a second position blocking the gas passageway; a movable member mounted in the gas passageway in a position other than the sealing member; and a temperature-responsive member disposed in the valve housing, the movable member being movable by the temperature-responsive member in response to a temperature of the combustion chamber to thereby vary an area of cross section permitting gas flow.

2. The gas-heatable appliance as claimed in claim 1, further comprising a switch movable between an on position and an off position for controlling ignition of the inflammable gas.

3. The gas-heatable appliance as claimed in claim 1, wherein the sealing member is in the first position when the switch is in the on position.

4. The gas-heatable appliance as claimed in claim 1, wherein the sealing member is in the second position when the switch is in the off position.

5. The gas-heatable appliance as claimed in claim 1, wherein the valve housing comprises an upper seat and a lower seat, the sealing member being sandwiched between the upper seat and the lower seat.

6. The gas-heatable appliance as claimed in claim 5, wherein the upper seat comprises a first face and a second face opposite to the first face, the upper seat comprising a first hole extending from the first face of the upper face through the second face of the upper seat, a second hole extending from the first face of the upper face through the second face of the upper seat and receiving the temperature-responsive member, and a third hole extending from the first face of the upper face through the sit second face of the upper seat and communicating with the combustion chamber, the upper seat further comprising a first passageway communicated with the second hole; the lower seat comprising a first face and a second face opposite to the first face of the lower seat, the lower seat comprising a fourth hole extending from the first face of the lower seat through the second face of the lower seat, communicating with the inflammable gas reservoir, and aligning with the second hole of the upper seat, the movable member being mounted in the fourth hole of the lower seat, a second passageway being defined in the first face of the lower seat and communicating with the third hole of the upper seat, a third passageway being defined in the first face of the lower seat, an engaging slot being defined in the first face of the lower seat for intercommunicating the second passageway and the third passageway, the engaging slot aligning with the first hole; the sealing member being resilient and comprising a fifth hole for intercommunicating the third hole of the upper seat with the second passageway of the lower seat, a sixth hole for intercommunicating the first passageway of the upper seat with the third passageway of the lower seat, and a seventh hole for intercommunicating the second hole of the upper seat with the fourth hole of the lower seat, the sealing member being deformed into and thus blocking the engaging slot when the switch is in the off position, the sealing member restoring its shape and thus disengaging from the engaging slot when the switch is in the on position.

7. The gas-heatable appliance as claimed in claim 6, wherein the third hole of the upper seat is a screw hole having a threaded section, further comprising an outlet tube having a threaded end engaged with the threaded section of the screw hole, the outlet tube comprising a longitudinal hole communicated with the combustion chamber and the fifth hole of the sealing member.

8. The gas-heatable appliance as claimed in claim 6, further comprising: an engaging member received in the first hole and comprising a first end and a second end extending beyond the first hole, the first end of the engaging member being operable to deform the sealing member; an elastic member for biasing the first end of the engaging member to deform the sealing member; and a control member securely attached to the second end of the engaging member, the control member being actuatable by the switch to overcome the elastic member, thereby allowing the sealing member to restore its original shape when the switch is in the on position.

9. The gas-heatable appliance as claimed in claim 8, wherein the first hole of the upper seat is a stepped hole having a flange, the elastic member being mounted around the engaging member and having two ends attached to the first end of the engaging member and the flange of the first hole.

10. The gas-heatable appliance as claimed in claim 6, wherein the fourth hole of the lower seat comprises a conic hole for receiving the movable member, the fourth hole of the lower seat further comprising a port for intercommunicating the inflammable gas reservoir with the conic hole.

11. The gas-heatable appliance as claimed in claim 10, wherein the movable member is a ball.

12. The gas-heatable appliance as claimed in claim 11, further comprising an elastic member for biasing the ball away from the port.

13. The gas-heatable appliance as claimed in claim 10, wherein the movable member comprises a conic portion.

14. The gas-heatable appliance as claimed in claim 13, further comprising an a elastic member for biasing the ball away from the port.

15. The gas-heatable appliance as claimed in claim 6, further comprising a regulating member mounted in the fourth hole of the lower seat, the regulating member comprising a conic hole for receiving the movable member, the regulating member further comprising a port for intercommunicating the inflammable gas reservoir with the conic hole.

16. The gas-heatable appliance as claimed in claim 15, wherein the movable member is a ball.

17. The gas-heatable appliance as claimed in claim 16, further comprising an elastic member for biasing the ball away from the port.

18. The gas-heatable appliance as claimed in claim 15, wherein the movable member comprises a conic portion.

19. The gas-heatable appliance as claimed in claim 18, further comprising an elastic member for biasing the ball away from the port.

20. The gas-heatable appliance as claimed in claim 7, further comprising: an engaging member received in the first hole and comprising a first end and a second end extending beyond the first hole, the first end of the engaging member being operable to deform the sealing member; an elastic member for biasing the first end of the engaging member to deform the sealing member; and a control member securely attached to the second end of the engaging member, the control member being actuatable by the switch to overcome the elastic member, thereby allowing the sealing member to restore its original shape when the switch is in the on position.