Valves and valve actuation – Rotary valves – Seat or interface seal
Reexamination Certificate
2000-04-03
2001-07-17
Lee, Kevin (Department: 3754)
Valves and valve actuation
Rotary valves
Seat or interface seal
C251S309000
Reexamination Certificate
active
06260821
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention relates generally to paintball guns. More specifically, this invention relates to a paintball gun on/off valve for selectively controlling a supply of gas from a compressed gas source.
The industry has been unable to provide a reliable on/off valve for selectively supplying a flow of compressed CO
2
gas to a paintball gun from a CO
2
gas source. In particular, on/off valves of the prior art have problems, such as leakage of the CO
2
, and are therefore unreliable.
FIG. 1
is a perspective view of a paintball gun
50
having an on/off valve
100
according to the prior art.
FIG. 2
is an enlarged side elevation view of the on/off valve
100
of
FIG. 1
, showing the external attachment between a pressure regulator
55
of a paintball gun
50
and a compressed gas source
60
. The on/off valve
100
of
FIGS. 1 and 2
is typical for guns using compressed air or nitrogen as the compressed gas source
60
.
FIG. 2A
is a side elevation view of an on/off valve
100
A, similar to the valve
100
shown in
FIGS. 1 and 2
. The compressed gas source
60
A, used with the valve
100
A, is CO
2
.
FIG. 3
is a bottom right side perspective view of the prior art on/off valve
100
A of
FIG. 2A
, shown independent of attachment to external components. The only structural differences between the valve
100
shown in
FIGS. 1 and 2
and the valve
100
A of
FIGS. 2A and 3
are the type of actuator
122
used and the size of the valve.
FIGS. 1 and 2
show a lever-type actuator
122
on a larger valve for use with a compressed air or nitrogen gas source
60
, while
FIG. 3
shows a knob-type actuator
122
A for use with a compressed CO
2
gas source
60
A.
The internal configuration of the conventional on/off valves
100
,
100
A is shown in
FIGS. 4-7
. Specifically,
FIG. 4
is a horizontally cross-sectioned bottom plan view of the prior art on/off valve
100
A, shown in FIG.
3
.
FIG. 5
is an enlarged, vertically cross-sectioned, partial right side elevation view of the prior art on/off valve
100
A of FIG.
3
.
FIG. 6
is a front elevation view and a cutaway left side elevation view of a plug
120
for use in the prior art on/off valve
100
A of FIG.
3
.
FIG. 7
is a horizontally cross-sectioned bottom plan view and a vertically cross-sectioned front elevation view of a valve body
102
for use in the prior art on/off valve
100
A of FIG.
3
. The general internal configuration of the valve
100
is the same as that for valve
100
A, except with respect to the sizing of the components.
Referring to
FIGS. 4-7
, the prior art on/off valve
100
A has a valve body
102
with a gas inlet
110
and a gas outlet
112
extending longitudinally through the body
102
. The valve body
102
also includes a plug cavity
115
that extends laterally through the body
102
between the inlet
110
and the outlet
112
from a right side (top of
FIG. 4
) to a left side (bottom of
FIG. 4
) of the body
102
. A plug
120
is positioned within the plug cavity
115
. The plug includes a knob (or other actuator)
122
A that can be rotated 90° to switch the valve
100
A on or off. The actuator
122
A is attached to a plug stem
124
that extends into and through the plug cavity
115
. A flow aperture
125
is provided through the plug stem
124
, and is located at the lateral position of the inlet
110
and the outlet
112
, when the plug stem
124
is properly arranged inside the cavity
115
.
Two o-rings
126
,
126
A extend around the plug stem
124
within grooves
127
,
127
A on opposite lateral sides of the inlet
110
and outlet
112
. These o-rings
126
,
126
A provide a seal between the plug stem
124
and the wall of the cavity
115
to prevent the gas from leaking out through the plug ends and to ensure that the gas from the gas inlet
110
travels to the gas outlet
112
when the valve
100
A is open. A third o-ring
128
is provided along the external surface of the plug stem
124
within a circular-shaped groove
129
. The third o-ring
128
is designed to prevent gas from leaking into the outlet
112
and, hence, from flowing to the gun
50
, when the actuator
122
A is in an “off” (closed valve) position. Specifically, when the actuator
122
A is located in an “off” position, the o-ring
128
surrounds an entry port
113
of the outlet
112
, preventing the gas from entering the outlet
112
. It should be noted that the third o-ring
128
only performs its sealing function when the valve is in the “off” position.
Referring to
FIGS. 1-7
, the operation of the prior art on/off valves
100
,
100
A is as follows. When the actuator
122
,
122
A is located in an “on” (open valve) position, the flow aperture
125
in the plug stem
124
is arranged in communication with both the inlet
110
and the outlet
112
in order to permit the gas to flow from the inlet
110
to the outlet
112
. When the actuator
122
,
122
A is rotated 90° from the open position into a closed position, the third o-ring
128
slides into place around the entry port
113
of the outlet
112
, and the flow aperture
125
is positioned transverse to an axis running from the inlet
110
to the outlet
112
. This prior art system works fairly well for compressed air and Nitrogen systems which have larger valve sizes.
Unfortunately, however, this configuration has several disadvantages when used for CO
2
systems, which generally have smaller valves. In particular, the wall of the plug cavity
115
is very difficult to debur, particularly around the entry port
113
of the outlet
112
. This is because the cavity
115
and port
113
are located inside the valve body
102
. Inevitably, therefore, small, sharp protrusions are left on the wall surface of the cavity
115
. These protrusions tend to cut or slice the o-ring
128
as the plug
120
is rotated from the open to the closed position. Specifically, burs around the entry port
113
of the outlet
112
tend to slice the o-ring
128
as it slides past to reach the closed position. Once the o-ring
128
has been cut, it can no longer provide an adequate sealing function and gas will leak into the outlet
112
even when the valve
100
A is closed.
In addition, the o-ring
128
of the prior art valve
100
A is relatively large and pliable, e.g., a 007-70° Urethane (U) or Ethylene Propylene (EP) o-ring. With this o-ring
128
, when CO
2
is used as the compressed gas, the o-ring
128
has a tendency to absorb the CO
2
and expand as a result. Also, because the o-ring
128
is fairly large in proportion to the diameter of the plug
120
, it tends to come out of its groove
129
. Furthermore, pressure from the gas source tends to force the o-ring
128
into contact with the valve body
102
. The expansion forces and gas pressure increase the contact between the o-ring
128
and the body
102
, thereby increasing the likelihood that surface irregularities along the cavity walls (and particularly around the entry port
113
of the outlet
112
) will destroy the o-ring
128
. When the o-ring
128
is destroyed, the compressed gas begins to leak from the on/off valve
100
A, shortening the life of the gas source. Because of this, the prior art on/off valve
100
A is unreliable.
SUMMARY OF THE INVENTION
An object of the present invention is to enable a reliable on/off valve for a paintball gun.
This invention provides a significant improvement in the art by enabling an on/off valve for a paintball gun with improved reliability over the prior art. Specifically, an on/off valve for a paintball gun according to this invention comprises a valve body that has a plurality of gas apertures. The gas apertures include a gas inlet configured to receive a gas from a pressurized gas source, and a gas outlet configured to transmit the gas to a paintball gun. An actuator is configured to selectively control a flow of the gas from the gas inlet to the gas outlet. A seal is located inside a port of one or more of the apertures to prevent the gas from leaking.
In operation, the valve is switched between an open (“on”) position and a closed (“off”) po
Gardner, Jr. William
Perry Rod
Lee Kevin
Marger & Johnson & McCollom, P.C.
SmartParts, Inc.
LandOfFree
On/off valve for a paintball gun does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with On/off valve for a paintball gun, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and On/off valve for a paintball gun will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2467716