U.S. patent application number 13/424694 was filed with the patent office on 2013-08-01 for toy gun with pneumatic to hydraulic pressure magnifier.
The applicant listed for this patent is Chor-Ming Ma. Invention is credited to Chor-Ming Ma.
Application Number | 20130193161 13/424694 |
Document ID | / |
Family ID | 46959969 |
Filed Date | 2013-08-01 |
United States Patent
Application |
20130193161 |
Kind Code |
A1 |
Ma; Chor-Ming |
August 1, 2013 |
Toy Gun With Pneumatic to Hydraulic Pressure Magnifier
Abstract
A toy gun includes a hydraulic cylinder, a nozzle from which
water from the hydraulic cylinder can be expelled, and a hydraulic
piston movable in the hydraulic cylinder. The hydraulic cylinder is
of a certain surface area. A pneumatic piston is movable in a
pneumatic cylinder and is connected to the hydraulic piston. The
pneumatic piston has a surface area that is larger than that of the
hydraulic piston. Upon triggering, compressed air is delivered to
the pneumatic cylinder and pressure induced in the hydraulic
cylinder is magnified substantially by the ratio of the two surface
areas.
Inventors: |
Ma; Chor-Ming; (Kowloon,
HK) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Ma; Chor-Ming |
Kowloon |
|
HK |
|
|
Family ID: |
46959969 |
Appl. No.: |
13/424694 |
Filed: |
March 20, 2012 |
Current U.S.
Class: |
222/79 |
Current CPC
Class: |
F41B 9/0037 20130101;
F41B 9/0018 20130101; F41B 9/0065 20130101 |
Class at
Publication: |
222/79 |
International
Class: |
F41B 9/00 20060101
F41B009/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 30, 2012 |
HK |
12100859.6 |
Claims
1. A toy gun, comprising: a hydraulic cylinder; a nozzle from which
water from the hydraulic cylinder can be expelled; a hydraulic
piston movable in the hydraulic cylinder and having a hydraulic
surface area; a pneumatic cylinder; a pneumatic piston movable in
the pneumatic cylinder and connected to the hydraulic piston, the
pneumatic piston having a pneumatic surface area that is larger
than the hydraulic surface area; and means for presenting
compressed air to the pneumatic cylinder.
2. The toy gun of claim 1, further comprising a reservoir for
receiving water and compressed air above the water, and an inlet
valve enabling one-way flow of water from the reservoir to the
hydraulic cylinder.
3. The toy gun of claim 2, further comprising a priming pump for
compressing the air above the water in the reservoir.
4. The toy gun of claim 3, further comprising a fluid switch
adapted upon trigger-activation to release compressed air from the
reservoir to the pneumatic cylinder.
5. The toy gun of claim 4, further comprising a conduit extending
between the priming pump and the reservoir, and wherein the fluid
switch communicates air from a conduit to the pneumatic
cylinder.
6. The toy gun of claim 5, further comprising a trigger acting upon
the fluid switch.
7. The toy gun of claim 1, further comprising a nozzle valve
activated by the trigger.
8. The toy gun of claim 1, wherein the pneumatic piston is linked
or connected to the hydraulic piston by a connecting rod.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to toy guns. The invention
more particularly, although not exclusively, relates to
water-shooting toy guns exploiting pneumatic pressure to propel
water from a nozzle.
[0002] Due to the compressible nature of gases, compressed air is a
relatively inefficient propellant for firing water from toy guns.
For example, an effective 90 psi of hydraulic pressure behind the
nozzle is very difficult to achieve using stored pneumatic pressure
in a toy gun to be operated by children. However, 50 psi for
example is relatively easy to achieve as a stored pneumatic firing
pressure.
SUMMARY
[0003] Briefly stated, high hydraulic firing pressure is achieved
in a toy gun primed with relatively low pneumatic pressure.
[0004] There is disclosed herein a toy gun, comprising:
[0005] a hydraulic cylinder;
[0006] a nozzle from which water from the hydraulic cylinder can be
expelled;
[0007] a hydraulic piston movable in the hydraulic cylinder and
having a hydraulic surface area;
[0008] a pneumatic cylinder;
[0009] a pneumatic piston movable in the pneumatic cylinder and
connected to the hydraulic piston, the pneumatic piston having a
pneumatic surface area that is larger than the hydraulic surface
area; and
[0010] means for presenting compressed air to the pneumatic
cylinder.
[0011] Preferably, the toy gun further comprises a reservoir for
receiving water and compressed air above the water, and an inlet
valve enabling one-way flow of water from the reservoir to the
hydraulic cylinder.
[0012] Preferably, the toy gun further comprises a priming pump for
compressing the air above the water in the reservoir.
[0013] Preferably, the toy gun further comprises a fluid switch
adapted upon trigger-activation to release compressed air from the
reservoir to the pneumatic cylinder.
[0014] Preferably, the toy gun further comprises a conduit
extending between the priming pump and the reservoir, and wherein
the fluid switch communicates air from a conduit to the pneumatic
cylinder.
[0015] Preferably, the toy gun further comprises a trigger acting
upon the fluid switch.
[0016] Preferably, the toy gun further comprises a nozzle valve
activated by the trigger.
[0017] Preferably, the pneumatic piston is linked or connected to
the hydraulic piston by a connecting rod.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] A preferred form of the present invention will now be
described by way of example with reference to the accompanying
drawings, wherein:
[0019] FIG. 1 is a schematic cross-sectional elevation of parts of
a toy gun in a pre-priming configuration;
[0020] FIG. 2 is a similar schematic cross-sectional elevation of
the same parts at the commencement of priming;
[0021] FIG. 3 is a similar schematic cross-sectional elevation of
the same parts at a commencement of firing configuration;
[0022] FIG. 4 is a similar schematic cross-sectional elevation of
the same parts at a completion of firing configuration;
[0023] FIG. 5 is a similar schematic cross-sectional elevation of
the same parts in a post-firing configuration;
[0024] FIG. 6 is a similar schematic cross-sectional elevation of
the same parts at a trigger-released post-firing configuration;
and
[0025] FIG. 7 is a similar schematic cross-sectional elevation of
the same parts in a partially water-depleted condition ready for
re-priming.
DETAILED DESCRIPTION
[0026] In the accompanying drawings there is depicted schematically
the internal components 10 of a toy gun.
[0027] A reservoir 11 is sealed by a cap via which water can be
replenished. Extending upwardly into the reservoir 11 is a riser
tube 18. The riser tube 18 extends almost to the top of the
reservoir 11 so that its exit is above water level. The riser tube
18 is connected to a junction 17. A priming conduit 16 extends from
the junction 17 to a primer 13. Primer 13 comprises a reciprocating
handle 14 connected to a priming piston 15 which incorporates a
one-way valve 43. The one-way valve 43 at the priming pump prevents
backflow of air from the riser tube 16 to the pump.
[0028] Also attached to the junction 17 is a fluid switch 20
activated by a trigger 19.
[0029] Located beneath the reservoir 11 is a double cylinder 12
comprising a small diameter hydraulic cylinder 25 and a large
diameter pneumatic cylinder 23. A hydraulic piston 24 slides within
the hydraulic cylinder 25 and is sealed against the internal
cylinder wall 25 by an O-ring. Similarly, a pneumatic piston 22
slides within the pneumatic cylinder 23 and has an O-ring to seal
against the internal cylinder wall of the pneumatic cylinder 23.
Pistons 22 and 24 are fixed to one another by a rigid connecting
rod 26. The surface area of the hydraulic piston 24 is smaller than
the surface area of the pneumatic piston 22.
[0030] A firing conduit 21 extends between the fluid switch 20 and
the pneumatic cylinder 23.
[0031] At the front of the hydraulic cylinder 25 there is a
hydraulic firing chamber 30. A nozzle 31 extends from the hydraulic
firing chamber 30 to open space.
[0032] Immediately behind the nozzle 31 is a nozzle valve 32 from
which there extends a firing rod 28. The firing rod 28 is sealed
through an aperture of the hydraulic firing chamber 30 and biased
into the closed configuration by a nozzle valve return spring
33.
[0033] The firing rod 28 has a stopper 40 at its exposed tail
end.
[0034] The fluid switch 20 comprises a manifold casing having a
manifold rod 34 extending longitudinally through it. Attached to
the manifold rod 34 is a trigger 19. A trigger return spring 35
biases the trigger to the configuration depicted in FIG. 1.
[0035] Attached to the trigger 19 is a pull rod 41 having at its
distal end a catch 27 through which the firing rod 28 extends.
[0036] The manifold rod 34 is sealed into the manifold by a pair of
O-rings 37 and 38. These O-rings are fixed with respect to the
manifold casing and the manifold rod 34 slides with respect to the
O-rings. The manifold rod 34 has a circumferential or annular
recess 39.
[0037] The air gap between manifold rod 34 and the fluid switch
(manifold) casing forms the pneumatic exhaust port 36.
[0038] In the drawings, the letter "W" represents water or other
hydraulic liquid and a letter "A" represents pneumatic gas such as
air. For convenience, the words "water" and "air" are used.
[0039] In use, water is poured into the reservoir 11 and the cap
seals the reservoir 11. The handle 14 of the priming pump 13 is
reciprocated to build up pneumatic pressure in the priming conduit
16, junction 17, riser tube 18 and in the air above the water in
the reservoir 11.
[0040] Hydraulic pressure in the water of the reservoir rises
accordingly. As the inlet valve 29 is a one-way valve, water has
flowed from the reservoir 11 into the hydraulic firing chamber 30
and into the hydraulic cylinder 25 ahead of the hydraulic piston
24. The air trapped between piston 22 and conduit 21 will be vented
to atmosphere through exhaust port 36 via the gap between the
O-ring 37 and the annular recess 39 in the manifold rod 34. The
nozzle valve 32 is closed and continued reciprocation of handle 14
builds up hydraulic and pneumatic pressure in the system.
[0041] When trigger 19 is activated, it moves past the position of
FIG. 2 to the position shown in FIG. 3. The catch 27 of the pull
rod 28 pulls against the stopper 40. Accordingly, the firing rod 28
opens the nozzle valve 32 against the return spring 33. At the same
time, the annular recess 39 forms a flow channel around the O-ring
38 so that the pressurised air at the junction 17 passes rapidly
through the firing conduit 21 into the pneumatic cylinder 23.
[0042] If the pneumatic pressure behind the piston 22 is say 50
psi, the ratio of the diameter of pistons 22 and 24 will produce a
correspondingly increased hydraulic pressure in the water of
hydraulic cylinder 25. Such pressure might be around 90 psi. The
connecting rod applies an equal and opposite force between the
pistons. As the movement is dynamic in nature, there will of course
be some inefficiency due to slight frictional and leakage losses
when the nozzle is opened. The net force on the connecting rod 26
is to the left. As a result, both pistons 22 and 24 move in unison
to the left to cause a rapid jet of water through the nozzle
31.
[0043] When the trigger 19 is released as shown in FIG. 5, the
pistons 22 and 24 come to rest at the left and nozzle valve 32 is
sealed again. Air pressure inside the reservoir 11 will push water
into hydraulic firing chamber 30 again via inlet valve 29 as shown
in FIG. 6. In this configuration, the manifold rod 34 has moved to
the left, so that the annular recess 39 has formed a flow channel
around at O-ring 37 so that air substantially at atmospheric
pressure behind the pneumatic piston 22 escapes to atmosphere via
exhaust port 36.
[0044] The system then reverts to the configuration depicted in
FIG. 7 whereat the volume of water remaining in the reservoir 11
has diminished by the amount which escaped via a nozzle 31. The
system can continue to be primed as a solid portion of the manifold
rod 34 has sealed against O-ring 38.
[0045] It should be appreciated that modifications and alterations
obvious to those skilled in the art are not to be considered as
beyond the scope of the present invention.
* * * * *