Abstract
Disclosed is an actuator for actuation of a fluid dispense valve in a pressurized fluid powered fluid dispensing device. The actuator comprising structure to generate a pressure differential between a first zone and a second zone. The zones being adjacent a valve member of the fluid dispense valve of the device such that upon generation of the pressure differential the valve member is moved from the zone of relatively higher pressure towards the zone of relatively lower pressure such that the valve is opened.
Claims
1. An actuator for actuation of a fluid dispense valve in a pressurized fluid powered fluid dispensing device, the actuator comprising structure to generate a pressure differential between a first zone and a second zone, the zones being adjacent a valve member of the fluid dispense valve of the device such that upon generation of the pressure differential the valve member is moved by the pressurized fluid from the zone of relatively higher pressure of pressurized fluid towards the zone of relatively lower pressure of pressurized fluid such that the valve is opened.
2. An actuator according to claim 1, the actuator comprising structure to generate a partial vacuum adjacent a valve member of the fluid dispense valve of the device such that upon generation of the partial vacuum the valve member is opened.
3. An actuator according to claim 2, the partial vacuum creation structure comprising a pressure chamber adapted to be disposed in fluid communication with the valve member of the fluid dispense valve, the pressure chamber defining an internal volume, a pressurized fluid entry port to enable pressurization of the internal volume by pressurized fluid from a pressurized fluid source, the pressure chamber including a pressure release valve operable to enable release of pressurized fluid from the internal volume and an actuator body within the internal volume biased towards a first position and movable from the first position to a second position on operation of the pressure release valve to thereby generate in use, a partial vacuum chamber between the actuator body and the valve member to open the valve member.
4. An actuator according to claim 2, further comprising the fluid dispense valve for use in a pressurized fluid powered fluid dispensing device, the actuator body defining an actuator body volume, the valve member of the fluid dispense valve being received in the actuator body volume in slidable relation thereto such that on movement of the actuator body from the first position to the second position, the partial vacuum chamber is generated in the actuator body volume.
5. An actuator according to claim 3, comprising pressure equalization structure to cause closure of the valve member, the pressure equalization structure comprising a pressure equalization path into the partial vacuum chamber, the pressure equalization path being opened when the actuator body is in the second position.
6. An actuator according to claim 5, the pressure equalization structure including a port defined by the actuator body, and structure to vary the rate of pressure equalization through the port.
7. An actuator according to claim 5, the pressure equalization structure including a port defined by the actuator body and a port defined by the pressure chamber, the ports being disposed for fluid communication there between, the actuator body and or the pressure chamber being rotatable relative to one another to vary the extent of fluid communication through the ports.
8. An actuator according to claim 3, the pressure release valve being operable both to enable release of pressurized fluid from the pressure chamber and to obturate the pressurized fluid entry port.
9. An actuator according to claim 4, further comprising the outlet nozzle of the fluid dispensing device.
10. An actuator according to claim 3, further including an actuator housing, the actuator housing defining a fluid flow path for flow of pressurized fluid within the fluid dispensing device, the pressure chamber being mounted internally within the actuator housing, the actuator housing defining the pressure release port in fluid communication with the pressure chamber, and upstream and downstream fluid dispense and entry ports.
11. An actuator according to claim 4, wherein the pressurized fluid entry port of the pressure chamber and the pressure equalization path are both in fluid communication with the fluid flow path.
12. An actuator according to claim 3, wherein the actuator is pressurizable from a pressurized fluid reservoir of the fluid dispensing device, a source of pressurized fluid that is located remotely from the device, or an onboard pressurized fluid cartridge.
13.-25. (canceled)
26. A method of operating a valve in a pressurized fluid powered fluid dispensing device, the method comprising the steps of providing a pressurized fluid source to the device, and thereby also pressurizing an actuator pressure chamber, initiating movement of an actuator body in the pressure chamber by releasing pressure through an orifice of the chamber, the actuator body being in fluid communication with a valve member of the valve such that by reducing pressure in the chamber a pressure drop is created in the chamber between the actuator and the valve member by the pressurized fluid sufficient to cause movement of the valve member against the force of a biasing device to thereby open the valve.
27. A method according to claim 26, including the step of pressurizing the pressurized fluid powered fluid dispensing device by connecting the device to a source of pressurized fluid, such as mains water.
28. A method according to claim 26, including the step of pressurizing a fluid containing reservoir of the device by connecting the device to a source of pressurized fluid, such as mains water.
29. An actuator for actuation of a fluid dispense valve in a pressurized fluid powered fluid dispensing device, the actuator comprising, a housing structure, providing a fluid outlet, the housing structure supplied with fluid under pressure from a supply of pressurized fluid, an obturator at least in part within the housing, which when in a first position seals off a dump chamber from external low pressure, the dump chamber supplied with fluid under pressure, an actuator body at least in part within the housing, biased at least by the fluid under pressure in the dump chamber towards a first actuator body position, a valve member at least in part within the housing, biased at least by the fluid under pressure in a volume defined between the actuator body and valve member, toward a first valve member position, which seals the fluid outlet, on movement of the obturator to a second position fluid under pressure in the dump chamber is released to the low pressure, and supply of fluid under pressure to the dump chamber is also sealed off, fluid under pressure acting on the actuator body moves it from the first actuator position to a second actuator position, and in doing so the volume is also closed off from the fluid under pressure, the valve member is then biased by a pressure differential between the lower pressure in the volume and the surrounding fluid under pressure, toward a second valve member position which unseals the fluid outlet, at least one pressure equalization port is then opened to equalize the pressure differential when the actuator body reaches its second position, and the actuator body then moves back to its first position under action of a bias, this in turn moves the valve member back to its first position sealing the fluid let.
30. An actuator as claimed in claim 29, wherein movement of the valve member from its first to second position is caused by a low pressure in the volume, and fluid under pressure acting on a sealing face of the valve member to form the pressure differential.
31. An actuator as claimed in claim 29, wherein movement of the obturator from the second position back to its first position is provided by a bias.
32. An actuator as claimed in claim 31, wherein the bias may be mechanical such as a spring, or a formed by fluid pressure acting on a pressure surface.
33. An actuator as claimed in claim 29. wherein the size of the equalization port may be adjusted to control the time take for the valve member to close after opening.
34. An actuator as claimed in claim 29, wherein the valve member and actuator body are at least in part contained within and can slide along, and can seal to, an actuator cylinder, itself contained at least in part within the housing, the actuator cylinder containing one equalization port, the actuator body containing another of the actuation ports.
35. An actuator as claimed in claim 34, wherein the actuator cylinder forms the dump chamber.
36.-39. (canceled)
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0056] FIG. 1 is a longitudinal sectional view of an embodiment of a pressurized fluid powered fluid dispensing device according to a second aspect of the invention;
[0057] FIG. 2. is a cut away isometric view of the device shown in FIG. 1;
[0058] FIG. 3 is an enlarged sectional view of the part marked A in FIG. 1 in a first position, in accordance with a first aspect of the invention;
[0059] FIG. 4 is a view of the part of FIG. 3 in a second position;
[0060] FIG. 5 is a view of the part of FIG. 3 in a third position;
[0061] FIG. 6 is a view of the part of FIG. 3 in a fourth position;
[0062] FIG. 7 is a view of the part of FIG. 3 in a fifth position;
[0063] FIG. 8 is a part longitudinal sectional view of a further embodiment of device according to the second aspect of the invention;
[0064] FIG. 9 is a part longitudinal sectional view of a further embodiment of device according to the second aspect of the invention;
[0065] FIGS. 10a and 10b are schematic illustrations describing the method of operation of devices according to the second aspect of the invention,
[0066] FIG. 11 shows an exploded isometric view of the fluid dispense valve shown in FIGS. 3 to 7, with the exception of the sealing elements,
[0067] FIG. 12 shows an exploded isometric view of the fluid dispense valve shown in FIGS. 13 to 17, with the exception of the sealing elements,
[0068] FIG. 13 shows a similar view to that of FIG. 3, a vertical cross section of a fluid dispense valve in the ready to dispense position, where instead of a spring bias to push the obturator sleeve to the ready position, the valve in FIG. 3 uses fluid pressure as the bias to reset the obturator sleeve, showing the fluid paths from the pressurized fluid reservoir through to the passageways, past the conical wall seal down the passages to behind the actuator body, and behind the valve member,
[0069] FIG. 14 shows a similar view to that of FIG. 4 where the fluid delivery valve has been triggered and the first stages of movement are ready to proceed,
[0070] FIG. 15 shows the first movement of the actuator body once the pressurized fluid behind it is dumped to atmospheric and a combination of fluid pressure and spring bias move it,
[0071] FIG. 16 shows the movement of the valve member in response to the low pressure behind it, the pressurized fluid in the passageway acting on the valve member to move it to the left as viewed allowing a shot of pressurized fluid to leave the nozzle,
[0072] FIG. 17 shows the fluid dispense valve reset and in the ready to fire position again the same as that shown in FIG. 13, the obturator sleeve has been moved back to the left by the pressurized fluid acting on it, the actuator body has moved all the way to the right again, and the valve member has also, closing off the nozzle,
[0073] FIG. 18 shows the fluid dispense valve being filled from a source of fluid under pressure connected to the spigot and the fluid flow path past the forced open valve member and to the fluid reservoir,
[0074] FIG. 19 shows a cross section of a valve similar to that of FIG. 13 wherein the valve is configured for automatic operation once triggered, at the ready to fire position,
[0075] FIG. 20 shows a similar view to that of FIG. 19, where the valve has been released to fire automatically, and the obturator has moved to the position to allow the valve system to operate and dispense fluid, in this case as a bullet of fluid,
[0076] FIG. 21 shows a similar view to that of FIG. 19 again where the valve is reset and ready to fire, the obturator has been latched and automatic operation has ceased, and
[0077] FIGS. 22a, 22b and 22c are schematic illustrations showing a sequence of operation of a further embodiment of device according to the invention.
DETAILED DESCRIPTION
[0078] Referring to the drawings, and in particular to FIGS. 1 and 3, in accordance with a first aspect of the invention there is illustrated an actuator 1 for actuation of a fluid dispense valve 2 in a pressurized fluid powered fluid dispensing device 3 (FIGS. 1 and 2), the actuator 1 comprising structure 4 to generate a partial vacuum adjacent a valve member 5 of the fluid dispense valve 2 of the device 3 such that upon generation of the partial vacuum the valve member 5 is opened.
[0079] An exploded view of the fluid dispense valve 2 is shown in FIG. 11 and a variation of this in FIG. 12 (for the variation shown in FIGS. 13 through 17) that operates on the same inventive principle. The valve 2 consists of a secondary housing 9 which is connected to a pressurized fluid reservoir (not shown here, but visible in FIGS. 1 and 2). Secondary housing 9 has an exhaust port 10 from an interior of the housing 9 to the external surrounding atmosphere 84. Within the secondary housing 9 is contained the actuator cylinder 18. This is slidingly and rotationally fixed in place relative to the housing 9. The structure 4 when held or engaged to the housing 9 prevents sliding movement along the axis 102. This is achieved by structure 4 sandwiching the actuator body 18 between it and the interior of the housing 9. Rotational fixing can be achieved in many ways. In the preferred form there is a complimentary engagement between the interior of the housing 9 and the cylindrical mounting wall 26 of the actuator body 18 where the wall 26 engages the housing interior. In one preferred embodiment this is a triangular in plan protrusion along the axis 102 and a receiving complimentary notch in wall 26. The actuator body 18 is fluidly sealed to the housing 9 interior by seal 28c on wall 26 as shown in FIG. 3, in this case as an o-ring.
[0080] Between the exterior of the actuator cylinder 18 and interior of the housing 9 sits the obturator or closure 14 and its port closure sleeve 48. Obturator 14 selectively seals, as will be described below, via its interior diameter to the exterior diameter of the actuator body 18 via seals 28a and 28b. The obturator 14 also slidingly seals, as will be described below, on its external diameter to the internal diameter of housing 9 via seal 101. Obturator 14 is actuated by pivot arm 63 pivoting on pin 63, activated, in the embodiment shown by trigger 61 by a user.
[0081] Obturator 14 is biased into the ready position by a bias, in the embodiment shown in FIGS. 3 through 11 this bias is a spring 49, and in the embodiment shown in FIGS. 12 through 21 the bias is achieved from the fluid under pressure acting on surface 48a (see FIG. 16 and Detail A). Surface 48a is a ring-shaped surface exposed to the fluid under pressure, the ring shaped surface 48a defined between the sealing diameter of seals 28a and 21b. The same integers in FIGS. 11 through 21 refer to the same features and described with reference to FIGS. 1 through 10. In this variation in FIGS. 13 to 21 surface 48a has two functions, firstly to provide the pressure surface 48a as described above to bias the obturator as described. Secondly when the obturator is in the ready to fire position as shown in FIG. 13, surface 48a allows bypass of fluid under pressure from passage way 17 via gap 20a to the clearance surface 48a and in turn, in that ready to fire position, past seal 28a and then to passages 35 to charge chamber 42. Surface 48a also provides a fluid communication bypass for fluid under pressure when the obturator 14 is in the fired position as shown in FIGS. 14 and 20, where it provides clearance for fluid under pressure from passageway 17 via gap 20a to the volume defined between seals 28a and 21b, to then allow the fluid pressure to bias the obturator 14 back to the left.
[0082] Tube 29 of actuator cylinder 18 is supported by hollow extending arms 34 from cylindrical mounting ring 20. Slidingly retained within the tube 29 is actuator body 6 which is biased toward spigot 22 end by spring 40 and fluidly sealed to the interior diameter of tube 29 by seal 86. Defined behind actuator body 6 is dump chamber 42, which in fluid communication with passages 35 in arms 34. In the position shown in FIGS. 3 and 13 of obturator 14 this chamber 42 is charged with fluid under pressure from passages 17 via aperture or gap 20a, preferably a plurality of gaps 20a. Thus actuator body 6 is biased by the spring 40 toward spigot 22.
[0083] Sliding and sealingly at least in part located within actuator body 6 is valve member 5, in the preferred form there is a seal 107. In the embodiment shown in FIGS. 3 through 7 this is a dynamic seal (ie there is no separate seal element sealing is achieved by the small tolerance between the two bodies, the pressure and speed of movement) and in the embodiment shown in FIGS. 13 through 17 it is a separate seal 107 mounted on valve member 5. The hollow of actuator body 6 and base 46 of valve member 5 defining a chamber as internal volume 39a which also contains bias 47, here shown as a coil spring. Valve member 5 is biased toward sealing at valve seat 23 against the interior of structure 4 at the conical nozzle portion 19 by a combination of bias 47 and fluid under pressure acting across the pressure surface defined by the sealing diameter of valve member 5 to the interior of actuator body 6, that is the area defined by seal 107 diameter, within chamber or volume 39a which is fluid communication with the fluid under pressure in passage way 17 via equalization port 43.
[0084] Actuator body 6 has portions 96 that slidingly engage in grooves 98 (see FIGS. 9, 11, 12 and 14) of structure 4. Rotation of structure 4, for example by control element 67 will therefore rotate actuator body 6 relative to actuator cylinder 18, and therefore vary the fluid communication path through apertures 37 and 43 (in FIGS. 6 and 17). The smaller the size of this fluid communication through apertures 37 and 43 the slower is the valve member 5 to reset and close and thus the larger the amount of fluid dispensed 103 from the spigot. Likewise, the larger the fluid communication aperture due to the rotation between apertures 37 and 43 the quicker is the valve member 5 to close and therefore the smaller is the amount of fluid dispensed 103. Passage ways 17 are fed with fluid under pressure from the reservoir 8 as shown by arrows in FIGS. 3 and 13.
[0085] The valve assembly in FIGS. 3 to 7, 11 and 13 to 21 is held together by clipping of the housing 9 over the structure 4, whilst still slowing the structure 4 to be rotated relative to the housing 9. A variation for holding the valve assembly together is shown in FIG. 12, where there is a separate retaining cap 99 that holds the structure 4 to the housing 9 and over-engages the housing 9 by clipping thereto.
[0086] As illustrated here in FIGS. 3 and 13 the actuator structure which generates the pressure differential is in this embodiment partial vacuum generation structure 4 comprises a sealed to atmosphere 84 pressure chamber 4 in fluid communication with a valve member 5 of the valve 2, the pressure chamber 4 containing an actuator body 6 reciprocable between a first position (shown here) and a second position (shown in FIG. 6), the chamber 4 defining a pressure release port 7 and providing a pressure equalization path 7a, the chamber 4 being pressurizable, in use, by pressurized fluid from a pressurized fluid reservoir 8 of the fluid dispensing device 3. The actuator body 6 is disposed within the pressure chamber 4 to be in proximity with the valve member 5 of the valve 2, the arrangement being such that on pressurization of the pressure chamber 4 and subsequent release of pressurized fluid through the pressure release port 7, movement of the actuator body 6 from the first position toward the second position is initiated to create a pressure drop in the pressure chamber 4 between the actuator body 6 and the valve member 5, to move the valve member 5 (shown in FIGS. 6 and 16) to thereby open the valve 2, movement of the actuator body 6 to the second position initiating pressure equalization via the pressure equalization path 7a to allow return of the valve member 5 to the closed position (shown for example in FIG. 1).
[0087] Referring to FIGS. 1 and 2, the actuator 1 of the first aspect of the invention is shown in position in a water gun device 3 of the pressurized fluid type, in accordance with a second aspect of the invention. The device 3 is formed in the shape of a long weapon such as an automatic rifle and comprises valve actuator 1, a pressurized fluid reservoir 8, a valve actuator trigger 50, a valve 2 and a fluid dispense nozzle 22, wherein valve actuator 1 is energizable to open valve 2 using pressure from the pressurized fluid reservoir 8 to dispense fluid from the nozzle 22.
[0088] As will be apparent from FIGS. 1 and 2, the actuator 1, reservoir 8 and trigger 50 are here provided as modules that can readily be fitted into many different forms of device 3, such as for example, but not limited to paintball guns, dart guns including toy foam dart guns or veterinary dart guns, with suitable modification.
[0089] The water gun 3 has an outer shell 51 of generally elongate cylindrical form, with a trigger guard formation/handle 52 depending from a lower, in use surface, a top handle 53, and a forend extension 54. Within the trigger guard 52, a trigger aperture 55 is formed in the outer shell 51. As viewed, at the right hand end of the shell 51 a nozzle barrel 56 is provided in the form of a re-entrant cylindrical protrusion extending outwardly from the flat end surface 57 of the shell. A series of circular barrel ports 58 is formed in the wall of the nozzle barrel to simulate a ported gun barrel. Within the shell 51, mounting formations 59 are formed extending from the inner surface at points along its longitudinal axis to allow for the mounting of internal components. A trigger lever channel 60 is provided along the lower, as viewed edge of the shell 51.
[0090] The shell may be formed by any convenient means but here is formed by injection molding of a plastics material.
[0091] The internal components of the actuator 1 are illustrated in detail in FIGS. 3 to 7 and 11 to 21, with FIGS. 3 and 13 showing the actuator in the at rest position, ready to fire. Actuator 1 comprises a generally cylindrical outer, or secondary housing 9 defining an internal volume and a vent to atmosphere in the form of exhaust port 10 to allow fluid to be released therefrom for example, to the surrounding atmosphere 84, but may also be captured or used elsewhere. At its left hand end as viewed, outer housing 9 includes reservoir connector 11 and at its right hand end it defines a circular opening 87. Reservoir connector 11 includes a circular section spigot 12 including an outer circumferential screw thread 13 (FIG. 1).
[0092] Within the internal volume of housing 9 is mounted the sealed to atmosphere pressure chamber 4, which in this embodiment is housed within an actuator housing, hereinafter referred to as inner casing 15. Pressure release port obturator or closure 14 is mounted in sliding relation about casing 15. Thus it can be seen that in this embodiment secondary, or outer housing 9 provides a convenient means for containing the various internal structures of the actuator 1 and otherwise connecting the actuator 1 to surrounding structures within a fluid dispensing device 3, and pressurized fluid reservoir 8, but as will be appreciated, it could be omitted.
[0093] Inner casing 15 is dimensioned to fit substantially within the internal volume of outer housing 9 and when in position further provides a closure for its right hand open end 87 as will be described below. Inner casing 15 comprises three main parts, namely frustoconical nozzle portion 19 partially contained within and without outer housing 9, actuator cylinder 18 and pressure release port obturator or closure 14. Frustoconical nozzle portion 19 and actuator cylinder 18 together define a circular section fluid flow passage 17 within inner casing 15.
[0094] Frustoconical nozzle portion 19 includes conical wall 21, which tapers towards straight section nozzle spigot 22, the general shape being of a funnel. Internally, the transition point between the wall 21 of the tapered portion and the wall of spigot 22 defines a circular valve seat 23. Externally, conical wall 21 includes circumferential flange 24 which extends outwardly a distance sufficient to reach outer housing 9 when the inner casing 15 is in position, closing circular opening 87, and defines seal seat 21a for location seal 21b which may be an o-ring, wiper, lip seal or similar, shown here seal 21b is an o-ring seal. At its right hand end as viewed, nozzle spigot 22 terminates at nozzle aperture 25. At its left hand end, conical wall 21 is open to receive actuator cylinder 18.
[0095] Actuator cylinder 18 takes the form of generally constant section longitudinally extending tube 29 including tube wall 30, terminating at one end in closed end 31 and at the other in open end 32. Tube wall 30 further defines pressure equalization paths 7a, which here take the form of equalization apertures 37, located adjacent tube open end 32, and tube end 32 itself (FIGS. 3 and 4, 13 and 14). Actuator cylinder 18 is mounted coaxially within cylindrical mounting ring 20 via four circumferentially equally spaced radially extending arms 34 which extend outwardly from cylinder tube wall 30 to mounting ring 20. The number of extending arms 34 may be of any number and for example two extending arms have been shown to work, three, five or more would also work. Alternatively, a flange may be used spanning between tube 30 and ring 20 with fluid apertures or passages from one side to the other in FIGS. 12 through 21 there are two mounting arms 34. Mounting ring 20 includes axially extending cylindrical mounting wall 26, the outer surface of which defines circumferential housing seal seat 27 with mounted O-ring seal 28, and circumferential obturator seal seats 27a with mounted O-ring seals 28a (FIGS. 3 and 4, 13 and 14). Again while o-rings are mentioned here, the function of sealing may be achieved by any other appropriate seal, such as but not limited to wiper seals, lip seals or similar.
[0096] Each arm 34 contains a pressure release port 7 which here take the form of radially outwardly extending passages 35 which pass from the interior of the actuator cylinder 18 within arms 34 terminating in apertures 36 in the surface of mounting ring 20. Passages 35 thus provide a means of fluid communication between fluid flow passage 17 and atmosphere, via actuator cylinder 18 and vent 10 when the closure 14 is open, described below.
[0097] Referring to FIGS. 3 and 13 actuator cylinder 18 and frustoconical wall portion 19 when assembled, together define a closed volume comprising fluid flow passage 17, as stated. The parts are assembled such that tube 29 is passed into the left hand open end of frustoconical wall portion 19 to the point where the end of wall portion 19 contacts mounting ring 20, gaps 20a, which act as pressurized fluid entry ports, being formed there between to allow pressurized fluid to flow into pressure chamber 4 (FIGS. 3 and 6, 13 and 16). In the preferred form the parts are held together at least in part by a friction fit between the actuator cylinder 18 and the wall portion 19.
[0098] Referring to FIGS. 3 and 4, 13 and 16 pressure release port obturator 14 comprises port closure sleeve 48 and sleeve biasing spring 49. Sleeve 48 comprises a cylindrical collar dimensioned to fit closely around the outside of the assembled frustoconical wall portion 19 and actuator cylinder 18, and cylindrical mounting ring 20 and in sealing relation with obturator O-ring seals 21b, 28a. It is provided on its inner surface with circumferential groove 48a approximately half way along its length. The position of sleeve 48 at rest (shown in FIGS. 3 and 13) relative to inner casing 15 is determined by spring 49 which biases sleeve 48 to the left as viewed, spring 49 extending between sleeve 48 and flange 24. Thus, it can be seen from FIG. 3 that at rest sleeve 48 closes off pressure release ports 7 from vent 10, whilst allowing fluid to flow through the ports 7 from fluid flow path 17 via groove 48a (FIG. 3), and sloping surface 48a in FIG. 13, and gaps 20a.
[0099] Still with reference to FIGS. 3 to 7 and 13 to 17, it can be seen that actuator cylinder 18 contains actuator body 6. Actuator body 6, sometimes referred to as a hammer, comprises a solid cylindrical head section 38 with a hollow cylindrical tail section 39 extending therefrom defining an internal volume 39a (FIGS. 3 and 13). The actuator body is 6 is disposed within the actuator cylinder 18 for axially reciprocal movement between a first position (FIG. 3) and a second position (FIGS. 6 and 16). An actuator body seal 86 is located to fluidly seal between the exterior of the actuator body 6 and the interior of the actuator cylinder 18, whilst still allowing the reciprocal movement. The actuator body seal 86 fluidly separates the front and rear of the actuator body 6. Actuator body 6 position at rest is biased towards the right as viewed by coil spring 40 or similar bias, and importantly, to the right of passages 35, such that it extends out of tube open end 32 of actuator cylinder 18, passing into frustoconical nozzle portion 19 and contacting the interior surface of conical wall 21 with which it closely abuts by virtue of chamfered end 41. Thus, in its rest position actuator body 6 and actuator cylinder 18 together define a chamber 42, sometimes referred to as a dump chamber. Actuator body 6 further includes actuator equalization port 43 and valve member closure ports 44 which in the rest position shown in FIGS. 3 and 13 are all located outside of actuator cylinder 18.
[0100] In the present embodiment as illustrated in FIGS. 1 and 2, actuator 1 is provided in a form that includes fluid dispense valve 2 for use in the pressurized fluid powered fluid dispensing device 3 of the second aspect of the invention, although this is not essential. Thus, as illustrated in FIGS. 3 and 13, actuator body 6 is located in close proximity with valve member 5. Valve member 5 is a cylindrical, generally bullet shaped formation, including a tapered head 45 dimensioned to fit within nozzle spigot 22 and a stepped base 46 attached to a valve member coil spring 47 or similar bias by which it is attached to the interior of the tail section of the actuator body 6. In FIG. 3 the valve member 5 is shown in the closed position, its tapered head 45 contacting valve seat 23 to close the valve.
[0101] Referring now to FIGS. 3 to 7 and likewise FIGS. 13 through 17, operation of the actuator 1 will be described in the context of the water pistol device 3 of FIGS. 1 and 2. In use, it is necessary for a user to first charge the device 3 with pressurized fluid, in this case, water. This is achieved by attaching nozzle spigot 22 to a suitable source of fluid, for example water under pressure such as a mains water tap, or hose or similar connection therefrom, as shown for example in FIG. 18 where fluid under pressure source 104 is sealed to spigot 22. As will be appreciated, spigot 22 can be provided in any of the usual standard sizes for connection of hoses and the like to taps. Shown is spigot seal 80 on the exterior perimeter of the spigot 22 to aid sealing to the supply of pressurized fluid or water 104, e.g. the hose or tap or similar. Once the spigot 22 is attached, the tap is opened and water is forced under pressure towards valve member 5. The water pressure unseats valve member 5 (to the left as illustrated in FIG. 18) allowing water to flow into fluid flow passage 17 of inner casing 15, around arms 34 and through reservoir connector 11 into fluid reservoir 8. Fluid reservoir 8 is of known type, and includes an expansion bladder into which the water passes. It may for example be manufactured from rubber, elastomer or similar materials. In other forms it may be a cylinder within which is a piston with a bias, such as a spring or gas, driving the piston to pressurize the cylinder and hence any fluid in it. As it fills, the expansion bladder expands within an expansion tube 81 to a set pressure beyond which water is allowed to exit via a pressure release safety valve (not shown). Fluid reservoir 8 expands longitudinally along the length of expansion tube 81 as well as radially of the longitudinal axis to fill expansion tube 81. In this case the expansion tube 81 is provided in each half of the outer shell 51 shown in FIGS. 1 and 2. In a preferred form the end of the fluid reservoir 8 has a seal stop 82 connected there to, which will also contact the end of the expansion tube 81 when the fluid reservoir is full.
[0102] The range of operating pressures that can be accommodated is in accordance with devices of this kind as known in the art. For example, normal domestic hose pressures are between 20 to 80 psi (approximately 1.3 bar to 5.55 bar), whilst the operating pressure of the valve, i.e. that supplied by the pressurized reservoir 8 is between 25 to 30 psi (approximately 1.7 to 2 bar) and preferably is 27 psi (approximately 1.86 bar), this range and operating pressures may of course vary without departing from the scope of the invention.
[0103] Once the set or desired pressure has been achieved the water tap can be closed and the nozzle spigot 22 released. At this point the actuator 1 within the device 3 and valve member 5, will again be in the position shown in FIGS. 3 and 13 preventing flow of pressurized fluid past valve seat 23 and hence out of the valve 2, however the fluid flow passage 17 of the inner casing will now be full of pressurized water. It is important to note that pressurized water is thus also contained within chamber 42, the pressure release ports 7, within arms 34 and groove 48a, with gaps 20a providing fluid communication with the fluid flow passage 17. By virtue of port closure sleeve 48 and seals 28 and 21b however, pressurized water is prevented from passing into outer housing 9. The weapon is now primed and ready to fire.
[0104] Referring to FIG. 1, a simple trigger mechanism is illustrated which consists of a trigger 61 slidably mounted in trigger aperture 55. Trigger 61 is attached to trigger lever 62 which is slidable within trigger lever channel 60 and attached at its distal end to bifurcated pivot arm 63, pivotable about pin 64. Pivot arm 63 includes rotatable attachment points by which it is connected to port closure sleeve 48.
[0105] To fire a burst of water or a bullet 103, trigger 61 is moved to the left as viewed, typically by a user's finger, which pulls trigger lever 62 to the left, causing pivot arm 63 to pivot to the left below the pin 64 and right about above the pin 64. Pivot arm 63 is connected to the exterior of closure sleeve 48, in the example shown by a pivotal connection 88 to allow relative rotational movement between the pivot arm 63 and sleeve 48.
[0106] Turning to FIGS. 4 and 14, this triggered movement of pivot arm 63 therefore forces port closure sleeve 48 to the right against the force of sleeve spring 49, or in the case of that shown in FIG. 14 against the bias of the pressurized fluid acting on surface 48a as described with reference to FIG. 16). This is illustrated in FIGS. 4 and 14, which shows port closure sleeve 48 moved to the right, relative to its position in FIG. 3. This opens previously closed pressure release ports 7 causing pressurized water contained in chamber 42 to rapidly pass through arms 34 into the space 89 defined by outer housing 9 and along the path of least resistance to exit through exhaust port 10. At the same time however, fluid flow around groove 48a and through gaps 20a is now prevented by seals 28a. Similarly in FIG. 14/13 passages 35 are sealed off from passageway 17 by obturator 14 sealing on seal 28a, and thus fluid will follow the same path to volume 89 and then to atmosphere by exhaust port 10.
[0107] The end surface of tail section 39 does not need to be sealed to the interior surface of conical wall 21, though it may be contoured to lie more closely against it as shown in FIG. 4, however in the variation shown in FIGS. 12 to 21 there is an additional seal on the valve member 5. As such the fluid pressure in passageway 17 is acting on the end surface effective pressure area 89 (the area that lies between the outer and inner diameters of the actuator cylinder 18 at that tail section 39). This is balanced at least by the fluid pressure in dump chamber 42, and the opposing surfaces available in space 5a when port 43 is in fluid communication with passageway 17.
[0108] Similarly, the tail end of the valve member 5 forms a first valve effective pressure area 91, being the pressure area between the outer diameter of the valve member 5 and the sealing diameter 92 at the valve seat 23 when in the closed position as shown in FIG. 4.
[0109] These pressure forces trying to open the valve 5 are in sum opposed by the bias 40 and 47, and fluid pressure acting on the actuator head surface effective pressure area 93 and the valve head surface effective pressure area 94, keeping the valve closed shown in FIG. 4.
[0110] Referring now to FIGS. 5 and 15, it can be seen that the rapid exit of pressurized water from the chamber 42 via exhaust port 10 to the relatively lower pressure of the atmosphere 84 surrounding the actuator 1 and the consequent pressure drop therein causes the actuator body 6 to move to the left, as viewed, against the force of biasing spring 40, from its first, or at rest, position. Movement of the actuator body 6 to the left as viewed is caused by a combination of valve member coil spring 47 acting on the actuator body 6, and initially water pressure in internal volume 39a from fluid flow passageway 17 via port 43, acting on the actuator body face 85 and against base 46 of valve member 5. As can be seen in FIGS. 5 and 15, port 43 is closed off to water pressure partway through its travel to the left.
[0111] Continuing with FIGS. 5 and 15, it can be seen that the rapid exit of pressurized water from the chamber 42 and the consequent pressure drop therein causes the movement of the actuator body 6 to the left, against he force of the biasing spring 40 from its first or at rest position, away from valve member 5 and opens or expands a space 5a therebetween and at the same time closes actuator equalization port 43 by bringing it into the open end of actuator cylinder 18. As a result, pressurized water in flow passage 17 can no longer enter space 5a and the continued travel of the actuator body 6 to the left to its second position creates a partial vacuum, or lower pressure in space 5a between the actuator 6 and the valve member 5, than the surrounding fluid in passage 17. The tolerances of the outer diameter of actuator 6 and the internal diameter of the bore of the actuator cylinder 18 are such that under the rapid movement of the actuator body 6 there is effectively a dynamic seal between the two such that pressure in the time frame of the movement of the actuator body cannot equalize between space 5a and passage 17. In other embodiments (described below) there is a physical seal 107 is present between the two.
[0112] Referring to FIGS. 6 and 16 the partial vacuum, or low pressure, in space 5a compared to passageway 17, pulls the valve member 5 to the left, clear of the valve seat 23 to allow pressurized water to exit from passageway 17 through nozzle aperture 25. Further fluid pressure can act, at least initially on opening of the valve member 5 against the second valve effective pressure area 95, that is across the full diameter of the valve member 5, further opening the valve.
[0113] Referring now to FIGS. 7 and 17, when the actuator body 6 reaches the second position as shown, pressurized water or fluid flowing back into the partial vacuum chamber 5a created between the actuator body 6 and the valve member 5, via alignment of equalization port 43 and pressure equalization path 7a (as aperture 37), causes the valve member 5 to rapidly return to the right under the force of the spring 47 and the valve 2 is then closed. As will be appreciated, pressurized fluid can flow into the partial vacuum chamber 5a via the clearance between the actuator body 6 and the tube wall 30, and/or via aperture 37 therein under longer time frames. Pressure around the actuator body 6 (that is between chamber 42 and space 5a) is thus equalized and actuator body 6 returns to the first position under the biasing force of actuator spring 40. Thus, it will be appreciated from the foregoing that by varying the sizes, number and positions of equalization ports 43 and pressure equalization paths 7a (as aperture 37), a variability in valve opening duration can be achieved as previously described. Pressure equalization of space 5a to chamber 42 can be controlled and varied by the relative alignment of aperture 37 and equalization port 43. Put simply, the larger the volume of the passage or cross-sectional size of the orifice available for pressure equalization, the faster the valve 5 will close, thus providing a means of varying that volume or orifice size allows a user to vary valve opening duration at will. In the present embodiment this variation is achieved by providing actuator body 6 as rotatable relative to and within the cylinder 18 such that the circumferential position of port 43 and aperture 37 can be varied. Rotation will thus bring more or less of aperture 43 into register with aperture 37 according to the user's preference to cater for applications of the device 3 that require faster or slower valve opening duration. Rotation can be achieved by the user and is described below with reference to FIG. 9.
[0114] Referring now to FIG. 8, a second embodiment of device 3 is illustrated. In this embodiment, rather than the device being filled through the nozzle spigot 22, a dedicated fill conduit 65 is provided through which pressurized fluid such as water can be passed into fluid flow passage 17 via aperture 66 and from there, via the pathway previously described, into the fluid reservoir 8.
[0115] Referring now to FIG. 9 and FIGS. 11 to 21, a further embodiment of actuator 1 in accordance with the first aspect of the invention is illustrated. This embodiment includes an externally operable control element 67 which can be operated by a user to rotate actuator body 6 within cylinder 18, thereby providing a means of adjusting valve opening duration as described above, but here, without the need to partially disassemble the device 3. Control element 67 is connected to inner casing 15. A sliding engagement is present between the interior surface of inner casing 15 and actuator 6. In the embodiment shown this is via portion 96 extending from
[0116] In a further embodiment, (not shown), the device 3 is provided without an onboard pressure reservoir. Thus, reservoir connector 11 of outer housing 9 is provided in the form of a user accessible high pressure connector of known type, such as for example M22, threaded or quick connect, and pressurized fluid is fed from an external source via an umbilical. As a yet further alternative, the device 3 is provided with a user accessible cartridge compartment in place of reservoir 8 which is adapted to removably receive a CO.sub.2 cylinder of known type, reservoir connector 11 being adapted to connect with and pierce an inserted cylinder to achieve pressurization of the device 3.
[0117] FIGS. 10a and 10b are schematic drawings which illustrate different modes of operation of a device 3 according to the second aspect of the invention. FIG. 10a illustrates the mode of operation of operation of device 3 such as those illustrated above. FIG. 10b illustrates the mode of operation of a device 3 that includes additional or secondary fluid dispense apparatus 68. Such a device could for example be a chemical spray gun in which a chemical such as a fertilizer or weed killer concentrate is diluted and dispensed. In FIG. 10b it can be seen that fluid pressure from reservoir 69, in addition to providing the motive power for dispensing the primary fluid (shown by forward hatching) also pressurizes a secondary fluid storage chamber 70. Instead of having a trigger mechanism that operates using the pressure from the primary fluid to open the valve, here a trigger mechanism 71 is provided that uses pressurized secondary fluid (rearward hatching) to both work the valve and also provide secondary fluid to the primary fluid stream as it is dispensed in order to use the force of the primary fluid to provide mixing of the primary and secondary fluids.
[0118] An automatic version of the valve as a variation in the bias of obturator 14 is described with reference to FIGS. 19 through 21. The obturator 14 has a first pressure area (ring shaped) defined between the sealing diameters of seals 28b and 28a which pressure area biases the obturator to the right as viewed by the fluid under pressure present in sealed volume 89, which is in fluid communication with passages 17 as described earlier through gap 20a. The obturator 14 is prevented from moving to the right as viewed by sear 105 engaged to the obturator as shown in FIG. 19 preventing its movement.
[0119] On disengagement of the sear 105 from the obturator 14, for example by a trigger action as earlier described, but which trigger action pulls the sear downwards as viewed, the obturator 14 is then free to move to the right due to the pressure bias described above. As the obturator 14 initially opens and unseals from seal 28b, there is a greater pressure area formed briefly, again ring shaped, between seals 28a and 101. This for a short period of time until volume 89 equalizes with atmospheric also acts to move obturator 14 to the right. The firing process of the valve as earlier described is now set in motion.
[0120] Once moved to the right and volume 89 has equalized with atmospheric 84, as shown in FIG. 20, the pressure on first pressure area is reduced as that pressure has vented to atmosphere through port 10, again the same exhausting process as described earlier. The actuator body 6 and valve member 5 then follow the same activation as earlier described with reference to FIGS. 3 through 7 and 13 through 17 and dispense fluid from the spigot 22 and then close. Again, the amount dispensed can be controlled by the register of apertures 43 and 37 as earlier described to vary the fluid passage way therethrough.
[0121] After firing there is fluid under pressure from passage way 17 via gap 20a acting on a second pressure area (again also ring shaped, similar to that of area 48a in FIG. 16) as defined now between the sealing diameters of seals 21b and 28a. Fluid under pressure is retained in the volume between seals 28a and 21b and acts on second pressure surface 48a. This creates a force that is higher than the force provided by the low pressure on the first pressure area, as this has exhausted to lower pressure atmospheric. The obturator 14 therefore, in the same return method as described in FIG. 16, is now biased by the force on the second pressure area to move to the left to seal off volume 89 from exhaust port 10 and lower pressure atmosphere and the whole valve system repressurizes and resets to a ready to fire position the same as in FIGS. 3, 13 and 17.
[0122] Optionally, not shown here but shown in FIG. 3, there is a bias as a spring acting on the obturator 14 to return it to the left.
[0123] However, if the trigger is still depressed and therefore sear 105 is not engaged to obturator 14 the obturator can now repeat the cycle, moving to the right, opening the volume 89 to the exhaust, sealing off flow of fluid to the volume 89, and the valve will fire, dispensing fluid again. Dispensing of fluid again can be thought of a small body of fluid released with velocity from the spigot 22. The obturator 14 will then be biased back to the right, and so on.
[0124] This process will continue until either the fluid under pressure falls to that of atmospheric, though in reality given there is friction of the seal within the system the pressure will be slightly above atmospheric, or the pressurized reservoir 8 runs out of fluid.
[0125] The valve as described in FIGS. 1 to 21 can be used in a number of applications. For example, but not limited to, the gun-like water toy depicted. The valve also may be used in a hand-held shooter that may be mounted to the wrist being triggered by motion of the user's hand relative to the wrist, a ground mounted toy that periodically or randomly releases a jet of water vertically, such timing and amounts controlled as described above. A fluid powered vehicle or toy is also envisaged using the valve, where automatic (pulsed) and/or continuous (stream or jet) release of the fluid provides a jet to power the toy directly or indirectly. The release may be until exhaustion, or be by set amount of fluid being released or time passed.
[0126] FIGS. 22a to 22c are schematic drawings which illustrate a further embodiment of actuator in accordance with the first aspect of the invention. In this embodiment, rather than creating a partial vacuum, actuator structure 4 is adapted to create a zone of increased fluid pressure adjacent a part of the valve member 5 in order to move the valve member 5 from the zone of increased fluid pressure to a zone of relatively lower fluid pressure, to open the valve. For ease of exposition and clarity, structures which are common with the previously described embodiment have been omitted. FIG. 22a illustrates the device when it is pressurized and ready to fire. In this embodiment pressurized fluid X is allowed to enter upstream of the valve member 5 via fluid entry ports A2. As will be appreciated, this is upstream by reference to the direction of travel of the valve member 5 during the valve opening sequence. The fluid enters chamber A1 which is thus brought to the operating pressure of the device. When the device is triggered, pressurized fluid is released to atmosphere from downstream of the valve member, as described previously with reference to FIG. 4. This is shown in FIG. 22b. This initiates movement of the actuator body 6 to the left as viewed, hydro-locking chamber A1 and the valve member 5 also moves to the left and the valve is opened. Movement of the actuator 6 to the left as viewed brings into register equalization ports A3 and A4 allowing pressure release indicated by arrows Z, and the valve member 5 is returned to the closed position. The actuator body 6 is returned to the closed position by a return spring (not shown).
[0127] In addition to the water or fluid based described here the present invention may be used in other area. For example further recreational applications are for paintball guns, and foam dart guns. In other areas the present invention may be used for agricultural liquid dispensers for liquids such as herbicides, pesticides and fertilizers; dart guns for veterinary use or application of veterinary treatments, e.g. cutaneously, subcutaneously, oral or nasal or other.
[0128] A fast acting valve in the present invention has advantage and can find application where precise or targeted application of a fluid is desirable, as above in agriculture, but also for example in industry, where quick and easy accurate application of a fluid is needed, for example assembly lubrication, thread-lock or other applications.
[0129] Further a fast acting valve such as the present invention may prove beneficial to allow for fast movement over an area with fast and accurate application, again such as in agriculture, but also in industry, for example application of inks or similar over a large area, or repeated applications.
[0130] The foregoing description of the invention includes preferred forms thereof. Modifications may be made thereto without departing from the scope of the invention.
