Torch with integral flashback arrestor and thermal shut-off device

Abstract

A torch with integral flashback arrestor and thermal shut-off device is provided. In one approach, a torch body includes a passageway of the torch body, and a cartridge assembly disposed within the passageway. The cartridge assembly may include at least one of: a resettable pressure-sensitive device, and a thermal shut-off device, wherein the pressure-sensitive device and the thermal shut-off device are modifiable from a first configuration to a second configuration in response to a pressure or temperature gradient in the torch body, and wherein the second configuration restricts flow through the passageway. The cartridge may further include a check valve disposed along the passageway, for example, within a bore of a bushing, or within a retainer coupled to the torch body at an inlet of the passageway.

What is claimed is: 
     
         1 . A torch body comprising:
 a passageway; and   a cartridge assembly disposed within the passageway, the cartridge assembly comprising:
 at least one of: a resettable pressure-sensitive device, and a thermal shut-off device, wherein the resettable pressure-sensitive device and the thermal shut-off device are modifiable from a first configuration to a second configuration in response to a pressure or temperature gradient in the torch body, and wherein the second configuration restricts flow of a gas through the passageway; 
 a bushing operable with at least one of: the pressure-sensitive device and the thermal shut-off device; and 
 a check valve positioned along the passageway of the torch body, the check valve operable with at least one of: the resettable pressure-sensitive device or the thermal shut-off device. 
   
     
     
         2 . The torch body of  claim 1 , wherein the bushing is a sintered filter press fitted within a bore of the cartridge assembly. 
     
     
         3 . The torch body of  claim 1 , the thermal shut-off device comprising:
 a guide received within an internal bore of a bushing;   a stem positioned within an internal area of the guide; and   an adaptor separated from the stem by a thermal component, wherein the adaptor has a plurality of openings through an end wall, and wherein the second configuration causes the stem to engage the adaptor to prevent flow of the gas through the plurality of openings through the end wall.   
     
     
         4 . The torch body of  claim 3 , the stem comprising:
 a first elongate member extending from a first side of a sealing device and into an internal area of the guide; and   a second elongate member extending from a second side of the sealing device and towards a central opening of the adaptor.   
     
     
         5 . The torch body of  claim 3 , wherein the guide includes a set of openings formed through a sidewall. 
     
     
         6 . The torch body of  claim 3 , the thermal shut-off device further comprising a spring disposed within the stem for actuating the stem towards the adaptor. 
     
     
         7 . The torch body of  claim 6 , wherein the thermal component is one of: a thermal plug made from a polymer configured to melt at a predetermined temperature to bring the adaptor in contact with a flange of the stem, and a resettable bi-metallic strip permitting flow of the gas to the adaptor in the first configuration, and permitting the spring to actuate the stem towards the adaptor in the second configuration. 
     
     
         8 . The torch body of  claim 7 , wherein the second elongate member extends through the central opening of the adaptor in the case that the thermal plug melts and the adaptor is brought into contact with the sealing device of the stem. 
     
     
         9 . The torch body of  claim 1 , wherein the resettable pressure-sensitive device is a piston actuated in response to an increase in back-flow pressure within the passageway. 
     
     
         10 . The torch body of  claim 1 , wherein the check valve is disposed within a retainer coupled to the torch body at an inlet of the passageway. 
     
     
         11 . The torch body of  claim 1 , wherein the check valve is disposed within check is provided within a bore of the bushing. 
     
     
         12 . A flashback arrestor comprising:
 a passageway of a torch body;   a resettable pressure-sensitive device disposed along the passageway, wherein the resettable pressure-sensitive device is modifiable from a first configuration to a second configuration in response to a pressure change in the torch body, and wherein the second configuration causes actuation of a piston within the passageway to prevent back-flow through the passageway; and   a check valve disposed within the passageway.   
     
     
         13 . The flashback arrestor of  claim 12 , the resettable pressure-sensitive device comprising:
 an inner sleeve biased by an inner spring;   an outer sleeve biased by an outer spring; and   a locking ball positioned along an outer surface of a main body of the piston within an opening of the inner sleeve, wherein a portion of the locking ball extends into an opening between the inner sleeve and the outer sleeve when the resettable pressure-sensitive device is in the first configuration, and wherein the locking ball extends into a groove of the main body when the pressure-sensitive device is in the second configuration.   
     
     
         14 . The flashback arrestor of  claim 12 , further comprising a thermal shut-off device including:
 a guide received within an internal bore of the passageway;   a stem positioned within an internal area of the guide; and   an adaptor separated from the stem by a thermal component, wherein the adaptor has a plurality of openings through an end wall, and wherein the second configuration causes the stem to engage the adaptor to prevent flow of a gas through the plurality of openings through the end wall.   
     
     
         15 . The flashback arrestor of  claim 14 , the stem comprising:
 a first elongate member extending from a first side of a sealing device and into an internal area of the guide;   a spring disposed within the first elongate member for actuating the stem towards the adaptor; and   a second elongate member extending from a second side of the sealing device and towards a central opening of the adaptor.   
     
     
         16 . The flashback arrestor of  claim 15 , wherein the thermal component is one of: a thermal plug made from a polymer configured to melt at a predetermined temperature to bring the adaptor in contact with a flange of the stem, and a resettable bi-metallic strip permitting flow of the gas to the adaptor in the first configuration, and permitting the spring to actuate the stem towards the adaptor in the second configuration. 
     
     
         17 . The flashback arrestor of  claim 16 , wherein the second elongate member extends through the central opening of the adaptor in the case that the thermal plug melts and the adaptor is brought into contact with the sealing device of the stem. 
     
     
         18 . A torch comprising:
 a torch body; and   a flashback arrestor disposed within a passageway of the torch body, the flashback arrestor comprising:
 a thermal shut-off device modifiable from a first configuration to a second configuration in response to a temperature gradient in the torch body, wherein the second configuration restricts flow of a gas through the passageway; 
 a retainer coupled to the torch body at an inlet of the passageway; 
 a bushing coupled to the retainer; and 
 a check valve disposed within the retainer. 
   
     
     
         19 . The torch of  claim 18 , the thermal shut-off device comprising:
 a guide received within an internal bore of the bushing;   a stem positioned within an internal area of the guide; and   an adaptor separated from the stem by a thermal component, wherein the adaptor has a plurality of openings through an end wall, and wherein the stem engages the adaptor to prevent flow of the gas through the plurality of openings through the end wall in the second configuration.   
     
     
         20 . The torch of  claim 19 , the stem comprising:
 a first elongate member extending from a first side of a sealing device and into an internal area of the guide;   a spring disposed within the first elongate member for actuating the stem towards the adaptor; and   a second elongate member extending from a second side of the sealing device and towards a central opening of the adaptor.   
     
     
         21 . The torch of  claim 20 , wherein the thermal component is one of: a thermal plug made from a polymer configured to melt at a predetermined temperature to bring the adaptor in contact with the sealing device of the stem, and a resettable bi-metallic strip permitting a flow of gas to the adaptor in the first configuration, and permitting the spring to actuate the stem towards the adaptor in the second configuration. 
     
     
         22 . The torch of  claim 21 , wherein the second elongate member extends through the central opening of the adaptor in the case that the thermal plug melts and the adaptor is brought into contact with the sealing device of the stem.