Inflation valve

Abstract: An inflation valve (100) comprises a valve housing (101) having an inner wall (102), a cylindrical inner chamber (103) terminating in a gas outlet (110), and a gas inlet bore (104) providing fluid communication between the inner chamber (103) and a pressurized gas source. A piston (105) enclosed in the inner chamber (103) comprises at one end a head (108) directed toward the gas outlet (110) and at the opposite end a valve actuator connector (106). The piston (105) further comprises a gas inlet seal (112a,112b), positioned between the head (108) and the actuator connector (106), that releasably seals the gas inlet bore (104) from the inner chamber (103) when the piston (105) is in a normal, non-actuated position. A valve actuator (107) connected to the actuator connector (106) operates to pull the piston (105) , thereby moving the gas inlet seal (112a,112b) away from the gas inlet bore (104) and putting the inner chamber (103) in fluid communication with the gas inlet bore (104) and pressurized gas source. A regulating spring (114) contacting the piston close to the actuator connector (106) is compressible by the force of pressure exerted by gas contained within the inner chamber (103) and the gas inlet bore (104) and operates to position the piston (105) to control or regulate the outlet pressure.

Description: Field of the Invention The present invention relates to valves and, more particularly, to an inflation valve for controlling the flow of pressurized gas in the inflation of inflatable devices such as aircraft emergency evacuation slides and rafts. Background of the Invention Inflation valves find extensive use in controlling the flow of a stored pressurized gas to a variety of inflatable devices such as emergency evacuation slides for aircraft, life rafts, crash bags, and the like. For example, U.S. Patent No. 5,009,249 to Fisher et al. discloses a pressure regulator for regulating an inflatable member such as a slide. The pressure regulator includes a spool valve balanced between a trigger mechanism on one end and a spring on the other. Actuating the trigger mechanism on one end causes the spool valve to be unseated by a first spring and thereby placed in a pressure regulating position by a second spring in opposition to the escaping fluid pressure acting on the valve. The first spring biases the spool valve to interconnect the outlet with the gas storage, and the second spring regulates the gas flow from storage to outlet in response to pressure change at the outlet. Similarly, U.S. Patent No. 4,549,870 to Wass discloses a raft inflation valve having a pin that provides a stop at one end of a spool valve and a spring at the other. Removing the pin allows the spring to urge the spool valve into an open position, thereby enabling inflation of the raft. The piston remains in the open position regardless of the pressure present within the valve during raft inflation. The raft inflation valve does not include integral means to return the piston in its closed position. US-3.204.926 discloses an inflation valve, a piston of which is biased towards a valve seat. As long as that inflation valve should remain closed, the piston is mechanically arrested as regards its movements away from the valve seat. For opening that inflation valve, the mechanical arrest of the piston is removed and the piston is allowed to move away from the valve seat. The movement of the piston away from the valve seat is effected by pressure within the inflation valve, which pushes the piston away from the valve seat. FR-A-2.088.830 discloses an inflation valve having a piston. For opening that inflation valve, the piston is moved away from a valve seat thereby opening an outlet port. This movement of the piston is effected by pressures originating from a pyrotechnical cartridge. Upon activation, the pyrotechnical cartridge builds up pressure acting on one end of the piston thereby pushing the piston in a direction away from the valve seat. A common problem of the above inflation valves is that valve openings are based on forces provided and generated internally within the inflation valves. Particularly, forces for opening these inflation valves are provided by springs within the valves or pressure built up within the valves effecting piston movements away from valve seats. In case, these forces cannot be provided internally within the valves, it is not possible to open these valves. Especially for applications, where opening of an inflation valve is required in an emergency case, such a failure can represent a severe problem. Moreover, the approach of the above inflation valves to employ internally provided forces for valve openings requires respective valve components, which lead to complex designs, increased fabrication costs and itself represents possible failure sources. Object of the Invention Thus, it is the objection of the present invention to provide an inflation valve, which requires less components and is less prone to failures in order to provide a reliable operation even in emergency cases. Summary of the Invention In view of the above problem, an inflation valve inflation valve comprising a valve housing having an inner wall, a cylindrical inner chamber, a gas outlet, and a gas inlet bore providing fluid communication between the inner chamber and a pressurized gas source, a piston enclosed in the inner chamber comprises at one end a head directed toward the gas outlet and at the opposite end a valve actuator connector, a gas inlet seal, positioned between the head and the actuator connector, that releasably seals the gas inlet bore from the inner chamber when the piston is in a normal non-actuated position and a valve actuator connected to the actuator connector is provided, wherein, according to the present invention, a regulating spring contacts the piston close to the actuator connector is compressible by the force of pressure exerted by gas contained within the inner chamber and gas inlet bore and operates to position the piston to control or regulate the outlet pressure, the cylindrical inner chamber terminates in the gas outlet and the valve actuator operates to pull the piston, thereby moving the gas inlet seal away from the gas inlet bore and putting the inner chamber in fluid communication with the gas inlet bore and pressurized gas source. Brief Description of the Drawings FIG. 1 is a cross-sectional view of an inflation valve of the present invention having a piston comprising a single component. FIG. 2 is a cross-sectional view of a valve of the invention having a piston comprising two components and a positive lock mechanism. FIGS. 3A and 3B are cross-sectional views of the positive lock mechanism included in the valve depicted in FIG. 2. FIGS. 3A and 3B depict the lock mechanism in, respectively, its non-actuated (locked) and actuated (unlocked) positions. Detailed Description of the Invention As shown in FIG. 1, an inflation valve 100 of the present invention includes a valve housing 101 having an inner wall 102 and a cylindrical inner chamber 103. A gas inlet bore 104 leading from a compressed gas source (not shown) intersects inner chamber 103. A piston 105 is enclosed by inner wall 102 of valve housing 101. Piston 105 includes at one end an actuator connector 106, to which is attached a valve actuator 107. At the other end of the piston 105 is a piston head 108 that engages with an outlet bore 109 at a gas outlet 110 that is disposed at one end of valve housing 101. Gas outlet 110 is connected to an inflatable device such as an aircraft emergency slide (not shown). Piston 105 is also provided with a gas inlet seal land 111 positioned between actuator connector 106 and piston head 108 and equipped with two O-ring seals 112a and 112b. If desired, O-ring seal 112a can be mounted at a corresponding position on piston 105 rather than on inner wall 102. When piston 105 is in its normal non-actuated position, gas seal land 111 and O-ring seals 112a and 112b prevent the flow of gas from gas inlet bore 104 to inner chamber 103. Operation of valve actuator 107 by pulling causes piston 105 to move within inner wall 102 of housing 101, unsealing gas inlet bore 104 and allowing gas to flow into the inner chamber 103 and thence to outlet 110. The end of valve housing 101 opposite gas outlet 110 is closed by an actuator housing 113 that guides valve actuator 107. Regulating spring 114 connects actuator housing 113 and the end of piston 105 nearest actuator 107. When gas is discharged into inner chamber 103 by operation of actuator 107 to move piston 105, spring 114 is compressed. The force of the pressure on piston 105, which diminishes as the discharged gas exits outlet 110, is counteracted by a substantially equal opposing force from compressed spring 114, causing piston 105 to return towards its original non-actuated position as the gas pressure at inlet bore 104 is reduced.. To provide against inadvertent actuation, inflation valve 100 can be provided with a safety lock mechanism that includes a detent 115 and a safety release pin 116. Before valve actuator 107 can be operated, pin 116 must be removed, which allows piston 105 to move within housing 101. As also shown in FIG. 1, valve actuator 107 can comprise a cable or rod 117 terminated by a ball 118, and actuator connector 106 can be a socket for retaining ball 118. The term "pulling" as applied to operating valve actuator 107 is employed to describe the mechanical moving of piston 105 toward actuator housing 113 and away from gas outlet 110. Conceivably, a handle (not shown) could be connected to actuator 107 in a way that would cause an individual operating valve 100 to exert a "pushing" force that nonetheless results in "pulling" of piston 105 toward housing 113 and away from outlet 110, as described. FIG. 2 is a front cross-sectional view of a valve 200 in accordance with the present invention. Valve 200 differs from the previously described valve 100 in having a piston comprising two components and a positive lock mechanism. However most of the elements of valve 100 are also contained for the same respective purposes in valve 200, including valve housing 101 having inner wall 102 and inner chamber 103, gas inlet bore 104, actuator connector 106, valve actuator 107, piston head 108, outlet bore 109 at gas outlet 110, gas seal land 111, O-ring seals 112a and 112b, actuator housing 113, regulating spring 114, cable or rod 117, and ball 118. As shown in FIG. 2, valve 200 further includes a piston 201 that comprises two interconnecting components 202 and 203. First piston component 202 includes piston head 108, gas seal land 111, and O-ring seals 112a and 112b, while second piston component 203 includes actuator connector 106, valve actuator 107, regulating spring 114, cable or rod 117, and ball 118. Piston components 202 and 203 are interconnected by corresponding flanges 204 and 205, respectively. Piston component 203 further includes at its juncture with component 202 a positive lock mechanism comprising detents 206 that, in their non-actuated, i.e., locked position, are disposed in a groove 207 in inner wall 102 of valve housing 101. The elements and operation of the lock mechanism will be described with reference to FIGS. 3A and 3B. In FIG. 3A is shown the lock mechanism in its non-actuated, i.e., locked position, wherein detents 206 are held in place by piston second component 203 and thus prevent movement of piston first component 202. Pulling operation of valve actuator 107, which is connected to second component 203 as shown in FIG. 2, causes component 203 to move away from first component 202 and allows detents 206, which preferably have rounded surfaces and can be spherical in shape, to exit groove 207 and slide down ramps 208 of flange 205, as shown in FIG. 3B. In its actuated, unlocked position, second piston component 203 is free to move along with interconnected first component 202 as the pulling operation of actuator 107 is continued. A snap ring 209 can be inserted in an annular groove 210 in housing inner wall 102 to serve as a stop for the lateral motion of flange 205 when second piston component 203 is caused to move by the pulling operation of valve actuator 107. Movement of interconnected components 202 and 203 of piston 201 results in unsealing of gas inlet bore 104, allowing gas to flow into the inner chamber 103 and thence to outlet 110. As described for valve 100, the force of the pressure on piston 205 of valve 200, which diminishes as the discharged gas exits outlet 110, is counteracted by a substantially equal opposing force from compressed spring 114, causing piston 205 to return towards its original non-actuated position as the gas pressure at inlet bore 104 decreases. Thus, the inflation valve of the present invention is desirably simple in its construction and operation. The trigger mechanism is kept to a minimum, including at one end a cable or rod that pulls directly on the valve piston, which is held in its normal, inactuated position by O-rings and a safety lock mechanism. When the cable or rod is pulled, the pressure from the pressurized tank opens the valve, the flow of gas being regulaled by the inlet pressure from the pressurized gas source and regulating spring at the end of the piston opposite the gas outlet to an inflatable device. Having thus described the preferred embodiment of the invention, those skilled in the art will appreciate that various modifications and additions may be made thereto without departing from the scope of the invention, as set forth in the following claims.

Claims: An inflation valve (100), comprising: a valve housing (101) having an inner wall (102) , a cylindrical inner chamber (103), a gas outlet (110), and a gas inlet bore (104) providing fluid communication between said inner chamber (103) and a pressurized gas source; a piston enclosed (105) in said inner chamber (103), said piston (105) comprising at one end a head (108) directed toward said gas outlet (110) and at the opposite end a valve actuator connector (106), said piston (105) further comprising a gas inlet seal (111) positioned between said head (108) and said actuator connector (106), said seal (111) releasably sealing said gas inlet bore (104) from said inner chamber (103) when said piston (105) is in a normal non-actuated position; and a valve actuator (107) connected to said actuator connector (106), characterized by said cylindrical inner chamber (103) terminating in said gas outlet (110), at least one regulating spring (114) contacting said piston (105) proximate said actuator connector (106), said spring (114) being compressible by the force of pressure exerted by gas contained within said inner chamber (103) and operating to return said piston (105) towards its normal non-actuated position, and said valve actuator (107) operating to pull said piston (105), thereby moving said gas inlet seal (111) away from said gas inlet bore (104) and putting said inner chamber (103) in fluid communication with said gas inlet bore (104) and said pressurized gas source. The inflation valve (100) of claim 1, wherein said gas outlet (110) further comprises an outlet seat for engaging said piston head. The inflation valve (100) of claim 1, wherein said gas inlet seal (111) comprises at least one O-ring seal (112a, 112b) disposed on said piston (105). The inflation valve (100) of claim 3 wherein said gas inlet seal (111) further comprises an O-ring seal disposed on said inner wall (102) of said housing (101). The inflation valve (100) of claim 1, further comprising an actuator housing (113) closing the end of said valve housing (101) opposite said gas outlet (110). The inflation valve (100) of claim 5, wherein said regulating spring (114) is confined by said actuator housing (101). The inflation valve (100) of claim 1, wherein said valve actuator(107) comprises a rod or cable (117) attached to said connector (106). The inflation valve (100) of claim 7, wherein said valve actuator (106) terminates in a ball (118) and said connector (106) is a ball socket. The inflation valve (100) of claim 1 further comprising a safety lock for preventing inadvertent actuation of said valve (100). The inflation valve (100) of claim 9, wherein said safety lock comprises a safety release pin (116) extending through said valve housing(101) and a detent (115) in said housing (101) substantially diametrically opposite said safety release pin (116) , said detent (115) preventing motion of said piston (105) within said housing (101) until said pin (116) is released. The inflation valve (100) of claim 1, wherein said piston (201) comprises first and second interconnecting components (202, 203). The inflation valve (100) of claim 11, wherein said first and second piston components (202, 203) are interconnected by corresponding flanges (204, 205) on said components (292, 203). The inflation valve(100) of claim 12, wherein said first component (202) comprises said piston head (108) and said gas inlet seal (111), and said second component (203) comprises said actuator connector (106), said connector (106) being attached to said valve actuator (107). The inflation valve (100) of claim 13, wherein said second piston component (203) further comprises a safety lock for preventing inadvertent actuation of said valve (100). The inflation valve (100) of claim 14, wherein said lock comprises detents (206) disposed on said flange (205) of said second piston component (203), said detents (206) extending into notches (207) in said inner wall (102) of said housing (101) when said lock is in a non-actuated, locked position. The inflation valve (100) of claim 15, wherein said flange (205) of said second piston component (2039 further comprises ramps (208) adjacent said detents (206), said detents (206), upon operating of said valve actuator (107), being caused to exit said notches (207) in said housing inner wall (102) and move down said ramps (208), thereby putting said lock in an actuated, unlocked position and enabling said interconnected components (202, 203) of said piston (201) to move within said housing (101). The inflation valve (100) of claim 12, further comprising a snap ring (209) disposed in an annular groove (210) in said inner wall (102) of said valve housing (101), said snap ring (209) acting to stop lateral motion of said flange (205) of said second piston component (203) resulting from pulling operation of said valve actuator (107).

Inventors: BERRY OLIVER, KORPANTY DANIEL C, LANZA CHRISTOPHER, THOMASULO GARY, BERRY, OLIVER, KORPANTY, DANIEL C., LANZA, CHRISTOPHER, THOMASULO, GARY
Applicants: CARLETON TECHNOLOGIES INC, CARLETON TECHNOLOGIES, INC.
Application year: 2000
Main classification: F16K15
IPC codes: F16K15