U.S. patent application number 10/282897 was filed with the patent office on 2004-01-22 for paintball markers.
This patent application is currently assigned to NPF Limited. Invention is credited to Marks, Nicholas John, Rice, John Ronald, Walker, Mark Andrew.
Application Number | 20040011344 10/282897 |
Document ID | / |
Family ID | 26246801 |
Filed Date | 2004-01-22 |
United States Patent
Application |
20040011344 |
Kind Code |
A1 |
Rice, John Ronald ; et
al. |
January 22, 2004 |
Paintball markers
Abstract
A paintball marker comprises a main body 110 and a barrel 112
defining a firing axis X-X, a trigger 122, and a grip 120 arranged
to be held in a hand of a user which operates the trigger. The grip
120 has a rear edge 134 arranged to engage the palm of the hand of
a user, the rear edge 134 being substantially vertical so as to
enable the marker to be held in a comfortable and controlled manner
during use.
Inventors: |
Rice, John Ronald; (Upper
Team, GB) ; Marks, Nicholas John; (Stoke-on-Trent,
GB) ; Walker, Mark Andrew; (Stone, GB) |
Correspondence
Address: |
Michael D. Rechtin
Foley & Lardner, One IBM Plaza
Suite 3300
330 North Wabash Avenue
Chicago
IL
60611-3608
US
|
Assignee: |
NPF Limited
Birmingham
GB
|
Family ID: |
26246801 |
Appl. No.: |
10/282897 |
Filed: |
October 29, 2002 |
Current U.S.
Class: |
124/73 |
Current CPC
Class: |
F41C 23/10 20130101;
F41A 19/10 20130101; F41B 11/00 20130101 |
Class at
Publication: |
124/73 |
International
Class: |
F41B 011/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 23, 2001 |
GB |
GB 0128137.3 |
Jan 15, 2002 |
GB |
GB 0200818.3 |
Claims
1. A method of using a paintball marker for firing a fracturable
dye pellet for use in playing a paintball game, comprising the
steps of: providing a user a paintball marker having a barrel with
a firing axis; a trigger; a main body without a stock portion which
enables holding the marker close to the user's face for aiming the
marker; a compressed gas system having inherently low recoil and
for propelling a fracturable dye pellet with the compressed gas
system actuated by the user pulling the trigger; and a trigger grip
frame which is coupled to the main body in a position to extend in
a direction substantially perpendicular to the barrel and the
firing axis; positioning the user's trigger hand on the trigger
grip frame while the marker is held close to the user's face with
the trigger hand held in an unstrained position as a result of the
trigger grip frame being substantially perpendicular to the barrel;
holding the paintball marker up close to the face of the user and
avoiding injury to the face of the user as a consequence of using
the low recoil compressed gas system to propel the fracturable dye
pellet and at the same time the user accurately aiming the marker
to propel the dye pellet from the paintball marker during the game
as a result of the unstrained positioning of the trigger hand on
the trigger grip frame and being comfortably maintained, while
holding the paintball marker close to the user's face; and holding
the paintball marker with the user's arms such that both arms are
folded in close to the body of the user to minimize the user's
profile to another game player and the paintball marker is enclosed
therebetween the body and the arms of the user.
2. The method as defined in claim 1 wherein both the trigger hand
below the fingers and the forearm of the user are positioned
substantially in a vertical plane when the user is actuating the
trigger.
3. The method as defined in claim 2 wherein the arrangement of the
trigger grip frame causes the user to position the wrist to turn
substantially within the vertical plane of the forearm and the
trigger hand during aiming and firing the paintball marker.
4. The method as defined in claim 1 wherein the thumb and fingers
of the user's trigger hand are positioned substantially
symmetrically about the trigger grip frame as a result of the
trigger grip frame being perpendicular to the barrel.
5. A paintball marker for use in playing a paintball game,
comprising: a paintball marker main body having no stock portion; a
supply of dye pellets; a barrel defining a firing axis; a trigger;
compressed gas means having inherently low recoil for propelling
one of the dye pellets from the paintball marker by the user
actuating the trigger to fire the system; trigger grip means
arranged for holding by a user's trigger hand which operates the
trigger and wherein the trigger grip means is positioned to extend
in a direction substantially perpendicular to the firing axis with
the trigger grip means for positioning the user's trigger hand
wrist in substantially an unstrained orientation when the paintball
marker is held near the user's face for aiming and firing and also
for causing the user's hand below the fingers to be substantially
in a vertical plane with the user's forearm when the user actuates
the trigger; and means for enabling the user to hold the paintball
marker up close to and in front of the user's face during the game
to obtain accurate aiming of the paintball marker while the
compressed gas means propels the dye pellet without any substantial
recoil and also avoiding injury to the user's face and the means
for enabling comprising the paintball marker main body having no
stock, the compressed gas system and the trigger grip means.
6. The paintball marker according to claim 5 wherein the trigger
grip means includes a rear edge and at least a portion of the rear
edge extends substantially perpendicular to the firing axis.
7. The paintball marker according to claim 5 wherein the trigger
grip includes a front edge and at least a portion of which is
substantially perpendicular to the firing axis.
8. The paintball marker according to claim 7 wherein the paintball
marker includes a trigger guard and the grip includes a lower
portion which is below the trigger guard and which includes a front
edge, and wherein the front edge of said lower portion is
substantially perpendicular to the firing axis.
9. The paintball marker according to claim 8 wherein the front edge
of said lower portion defines a plurality of finger positions in
which fingers of the user's trigger hand rest when the marker is in
use, and wherein said finger positions are substantially aligned in
said direction.
10. The paintball marker according to claim 5 wherein the trigger
grip includes a rear edge arranged to engage a palm of said trigger
hand, the rear edge including an upper part and a lower part which
is inclined to the upper part, thereby enabling the angle of the
user's palm to the firing axis to be changed by moving the position
of the trigger hand on the trigger grip.
11. The paintball marker according to claim 10 wherein the upper
part and the lower part are together formed as a continuous curve,
thereby providing a range of hand positions on the trigger grip and
with an associated range of angles for the user's palm.
12. The paintball marker according to claim 5 wherein the grip
defines at least two trigger hand positions, and wherein the angle
of the palm of the users trigger hand relative to the firing axis
differs by at least 100 between the two positions.
13. The paintball marker according to claim 5 wherein the means for
enabling comprises means for causing the user to position his arms
close to his body thereby establishing a minimal body profile for
another player aiming at the user.
14. The paintball marker according to claim 5 further comprising a
gas propellant port extending downwards from the main body and
forming a support arranged to be held by a user's non-trigger hand,
wherein said means for enabling further comprises the gas
propellant port.
15. The paintball marker according to claim 14 including a
compressed gas bottle mounted on at least one of the trigger grip
means, wherein said means for enabling is arranged to enable the
user to obtain accurate aiming of the paintball marker while the
gas bottle extends between a trigger arm and a non-trigger arm of
the user.
16. The paintball marker according to claim 6 wherein said rear
edge has a length in the direction extending substantially
perpendicular to the firing axis over which it can support the
user's trigger hand, and the rear edge extends substantially in
said direction over at least a third of said length.
17. The paintball marker according to claim 16 wherein the rear
edge is within ten degrees of said direction over at least a third
of its length.
18. A paintball marker according to claim 5 wherein the grip has a
rear edge having an upper end and a lower end, and the rear edge is
arranged such that, if an equilateral parallelogram is constructed
having two opposite corners vertically aligned one above the other
and level with said upper and lower ends respectively, and being
symmetrical about a vertical line through said opposite corners,
and having its sides each inclined at 5.degree. to said vertical
line, then a single length of the rear edge can be contained within
the parallelogram which length has a vertical height equal to at
least one third of the height of the rear edge of the grip.
19. A paintball marker according to claim 18 wherein said upper end
is the highest point on the grip rear edge which can be contacted
by said hand while it is firing the marker, and said lower end is
the lowest point on the grip rear edge which can be contacted by
said hand while it is firing the marker.
Description
[0001] The present invention relates to paintball markers, also
referred to as paintball guns, which are arranged to fire balls or
pellets containing a marking fluid such as paint, ink or dye. The
pellets are arranged to rupture on impact with a target so as to
mark it, leaving an indication of where it was hit.
[0002] Paintball has grown rapidly in popularity over recent years
and paintball markers have become increasingly more sophisticated
so as to improve the performance of paintball competitors.
[0003] Whilst there are many similarities between a paintball
marker and a real gun, one aspect of the use of paintball markers
which has developed away from that of real guns is the manner in
which the marker is held.
[0004] FIG. 1 shows a paintball competitor holding a conventional
paintball marker 10 in a commonly used position. The marker is held
with one hand 12 on the grip 13 and trigger and the other 14 on a
support which is frequently formed from the propellant port. The
marker 10 is held with the rear end of the main body 16 very close
to the competitors face 18. With the marker in this position, if
the user wants to keep his elbows in close to his body as shown in
FIG. 1, which is important for presenting the smallest possible
target profile for another competitor to aim at, the wrist 20 of
the trigger hand has to be markedly bent, or `goosed`, as shown.
Since the total weight of a paintball marker including the
propellant canister and a full load of pellets can be of the order
of two or three kilograms, it will be appreciated that supporting
it with the wrist 20 in this bent condition can lead to discomfort
or even strain of the wrist. Also as the hand tends to move away
from the rear edge of the grip 13 round to the side, this can lead
to a reduction in the level of control that the user has over the
marker, which can obviously affect his aim. Furthermore, the
standard tournament rules of paintball games require the paintball
marker to be operated in a semiautomatic mode wherein the user must
pull the trigger each time a dye pellet is to be propelled from the
marker 10. Moreover, it is common that during the typical paintball
game over a thousand dye pellets are fired by the player from the
paintball marker 10. This of course requires the trigger hand and
finger to be used each time; and the trigger hand and finger are
placed under substantial stress during the game, making it even
more important that the trigger grip frame be structured to
establish a comfortable, ergonomic position for the trigger hand of
the user.
[0005] FIG. 2 shows an alternative to the holding position of FIG.
1 in which the arm 22 of the trigger hand 12 is held out to the
side of the user's body. This allows the marker to be held close to
the user's face 18 without bending the wrist significantly, but
increases the area that the user presents as a target to
competitors, and is therefore disadvantageous during a paintball
competition.
[0006] Accordingly the present invention provides a paintball
marker comprising a main body and a barrel defining a firing axis,
a trigger, and a grip arranged to be held in a hand of a user which
operates the trigger, wherein the grip is arranged to extend in a
direction substantially perpendicular to the firing axis.
[0007] Preferably at least a portion of the rear edge of the grip
extends substantially perpendicular to the firing axis. More
preferably the length of said portion is at least a third of the
length of the grip. Preferably said portion is within 100 of
perpendicular to the firing axis.
[0008] Said portion may be a central portion of the rear edge, or
it can be an upper or a lower portion.
[0009] Preferably the grip has a front edge, at least a portion of
which is substantially perpendicular to the firing axis.
[0010] For example, where the marker includes a trigger guard and
the grip includes a lower portion which is below the trigger guard,
the front edge of said lower portion is preferably substantially
perpendicular to the firing axis. If the front edge of the lower
portion comprises a flat surface, then that flat surface may be
substantially perpendicular to the firing axis. If the front edge
of said lower portion defines a plurality of finger positions in
which fingers of the user's trigger hand will rest when the marker
is in use, then said finger positions are preferably substantially
vertically aligned one above the other.
[0011] Where the marker includes a trigger guard and the grip has
an upper portion which is behind the trigger guard, the front edge
of the upper portion is preferably substantially vertical.
[0012] Preferably the grip has a rear edge arranged to engage a
palm of a hand of the user, the rear edge having an upper part, and
a lower part which is inclined to the upper part, so that the angle
of the user's palm to the firing axis can be changed by moving the
position of the hand on the grip.
[0013] Indeed the present invention further provides a paintball
marker comprising a main body and a barrel defining a firing axis,
a trigger, and a grip arranged to be held in a hand of a user which
operates the trigger, wherein the grip has a rear edge arranged to
engage a palm of a hand of the user, the rear edge having an upper
part, and a lower part which is inclined to the upper part, so that
the angle of the user's palm to the firing axis can be changed by
moving the position of the hand on the grip.
[0014] Preferably the upper part is inclined to the vertical and
faces slightly upwards and the lower part is inclined to the
vertical and faces slightly downwards.
[0015] Preferably the upper part and the lower part are together
formed as a continuous curve, so as to provide a range of hand
positions on the grip with an associated range of angles of the
user's palm. The radius of curvature of the curve may be
substantially constant over at least half of the length of the
grip. The centre of curvature of the curve of at least one of the
upper and lower parts may be located substantially at a position in
which a finger of the trigger hand of the user will rest when the
marker is in use.
[0016] The present invention still further provides a paintball
marker comprising a main body and a barrel defining a firing axis,
a trigger, and a grip arranged to be held in a hand of a user which
operates the trigger, wherein the marker defines a finger position
in which at least one finger of the trigger hand of a user will
rest when the marker is in use, and at least a portion of the rear
edge of the grip has a centre of curvature substantially located at
said finger position.
[0017] Where the marker comprises a trigger guard, and the grip
includes a lower portion which extends below the trigger guard and
is arranged to support fingers of the user's hand which are not
protected by the trigger guard, said finger may be one of said
fingers.
[0018] Where the trigger is arranged to support a trigger finger of
the user when the marker is in use, and said finger of the trigger
hand may be said trigger finger.
[0019] Where the grip defines at least two hand positions, the
angle of the palm of the user's hand relative to the firing axis
preferably differs by at least 100 between the two positions.
Preferably the upper part and the lower part are each at least 5 cm
long and each have a radius of curvature of at least 5 cm.
[0020] Preferably the grip has a rear edge having an upper end and
a lower end, and the rear edge is arranged such that, if an
equilateral parallelogram is constructed having two opposite
corners vertically aligned one above the other and level with said
upper and lower ends respectively, and being symmetrical about a
vertical line through said opposite corners, and having its sides
each inclined at 5.degree. to said vertical line, then a single
length of the rear edge can be contained within the parallelogram
which length has a vertical height equal to at least one third of
the height of the rear edge of the grip. In some cases the length
of the rear edge which can be contained within the parallelogram
may have a vertical height equal to at least one half or even two
thirds of the height of the rear edge of the grip.
[0021] Said upper end may be defined as the highest point on the
grip rear edge which can be contacted by a user's trigger hand
while it is firing the marker, and said lower end may be the lowest
point on the grip rear edge which can be contacted by a user's
trigger hand while it is firing the marker.
[0022] The present invention further provides a grip frame for a
paintball marker having a main body, a barrel defining a firing
axis, and a trigger, the grip frame including a grip arranged to be
held in a hand of a user which operates the trigger, wherein the
grip is arranged to extend in a direction substantially
perpendicular to the firing axis.
[0023] Preferred embodiments of the invention will now be described
by way of example only with reference to the remainder of the
accompanying drawings in which:
[0024] FIG. 3 is a side view of a paintball marker according to a
first embodiment of the invention;
[0025] FIG. 4 is a detailed view of a grip frame forming part of
the marker of FIG. 3;
[0026] FIG. 5 is a side view of a user operating the marker of FIG.
3;
[0027] FIG. 6A is a front view of the user of FIG. 5; FIG. 6B
illustrates a user in a crouched position; and FIG. 6C illustrates
a user in a kneeling position;
[0028] FIG. 7 is a side view of a grip frame for a paintball marker
according to a second embodiment of the invention;
[0029] FIG. 8 is a side view of a grip frame for a paintball marker
according to a third embodiment of the invention;
[0030] FIG. 9 is a side view of a grip frame for a paintball marker
according to a fourth embodiment of the invention;
[0031] FIG. 10 is a side view of a grip frame for a paintball
marker according to a fifth embodiment of the invention;
[0032] FIG. 11 is a side view of a grip frame for a paintball
marker according to a sixth embodiment of the invention;
[0033] FIG. 12 is a side view of a grip frame for a paintball
marker according to a seventh embodiment of the invention;
[0034] FIGS. 13 and 14 are side views of the grip frame of FIG. 4
illustrating further analysis of the shape of grip frames according
to the invention; and
[0035] FIG. 15 is as side view of a grip frame for a paintball
marker according to an eighth embodiment of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0036] Referring to FIG. 3, a paintball marker according to a first
embodiment of the invention comprises a main body 110 and barrel
112, a grip frame 114 attached to the underside of the main body, a
propellant port 116 through which propellant in the form of
compressed gas is fed to the marker, and a feed port 118 through
which dye pellets are fed. As can be seen in FIGS. 1 and 3, the
propellant port 116 is also used as means for holding the marker
100 with the hand 14. The main body 110 and barrel 112 define a
firing axis X-X along which the pellets are fired. For ease of
description the firing axis X-X will be referred to as horizontal
and the direction perpendicular to it in the plane of FIG. 3 will
be referred to as vertical, although clearly in use the marker can
be held at any angle.
[0037] The grip frame 114 is removable as a unit from the main body
110 and includes a grip 120, a trigger 122 and a trigger guard 124.
In this embodiment the grip frame is actually made up of a frame
126 which is formed of metal such as aluminium, and a grip moulding
123 which is of moulded plastics. The frame 126 is shown in more
detail in FIG. 4 and includes a base portion 128 having a generally
flat upper surface 130 which rests against the underside of the
main body 110, a rear portion 132 which extends downwards from near
the rear end of the base portion 128 and forms the rear edge 134 of
the grip 120, a guard portion 136 which forms the trigger guard 24,
and a cutlass 137 which extends from the lower front corner of the
trigger guard 136 to the bottom of the grip 120. As can be seen in
FIG. 3, the grip 120 extends downwards substantially perpendicular
to the firing axis. The top surface 130 of the grip frame forms the
connection by which the grip frame 114 is connected to the marker
body 110 in use, and therefore defines the orientation which the
grip frame 114 will have, in use, in relation to the marker body
110 and the firing axis X-X. Therefore in this case, where the top
surface is parallel to the firing axis X-X, horizontal, in terms of
the grip frame 114, should be interpreted as meaning parallel to
the top surface 130, and vertical as perpendicular to the top
surface 130.
[0038] The rear edge 134 of the grip 120, i.e. that part of the
rear edge of the frame 114 which can be contacted by the palm of
the user's trigger hand when the marker is being fired, is,
generally speaking, vertical and has a length y in the vertical
direction which is defined as the vertical distance between its
upper end, which is at the highest point y1 that a user's hand can
rest on the rear edge 134, and its lower end, which is the lowest
point y2 that a user's hand can rest on the rear edge 134. However
it is curved, and has an upper hand supporting portion 134a which
faces slightly upwards, and a lower hand supporting portion 134b
which faces slightly downwards. The whole of the trigger hand
supporting rear edge 134 is formed as a continuous curve, and
between the upper and lower portions 34a, 34b it passes through the
vertical at a point 135 approximately two thirds of the way down
the grip. Also the central portion of the grip rear edge 134 around
this vertical point 135 is substantially vertical, with
approximately a third of the length of the rear edge 34 being at
less than 100 to the vertical. The central portion of the grip has
a vertical length h which is the vertical distance between the two
points y3, y4 on the rear edge 134 of the grip where the tangents
T1, T2 to the rear edge 134, in the vertical plane of FIG. 4, are
at 100 to vertical. The upper portion 134a of the grip rear edge
134 is shaped approximately in the form of an arc centred on a
point forward of the grip frame 114, and the lower portion 134b of
the grip rear edge 134 is also shaped approximately in the form of
an arc centred on the lower trigger finger position 144.
[0039] The trigger 122 is a two finger trigger, its forward edge
140 having an upper finger supporting portion 140a and a lower
finger supporting portion 140b, which define upper and lower
trigger finger positions 142, 144 respectively in which the
respective trigger fingers of a user will rest when held against
the trigger 122.
[0040] The front edge 138 of the upper portion 120a of the grip
frame is substantially vertical, and the front edge 139 of the
lower portion 120b of the frame 126 is also substantially vertical.
The front edge 146 of the moulding 123, which covers the front edge
139 of the lower portion 120b of the grip, is also substantially
vertical. This front edge 146 has a number of recesses 148, 150,
152 formed in it, and the bottom, i.e. rearmost, points of those
recesses are aligned with each other in a substantially vertical
line. The moulding 123 thereby defines a number of finger positions
154, 156, 158 which are aligned with each other in a substantially
vertical row, one above the other.
[0041] The result of the shape of the grip 120 is that the marker
can be held as shown in FIG. 5, with the palm of the trigger hand
113 facing forwards, rather than downwards as with a conventional
grip. This enables the user to hold the marker close to his face,
and point the marker in a horizontal direction without the
significant bending of the wrist that occurs in this position with
conventional markers.
[0042] In some situations there is room for the user's hand 113 to
be moved vertically up and down the grip. When the user's hand is
holding the grip 120 as close to the top as is comfortable, his
palm will be on the upper portion 134a of the rear edge 134 of the
grip 120 and will therefore be facing slightly downwards. This
means that, used like this, the grip will enable the marker to be
held in a similar manner to a conventional marker. However, if the
user moves his hand down and holds the grip 120 towards the lower
end, the palm of his trigger hand 113 will rest against the lower
portion 134b of the rear grip edge 134 and will therefore be facing
slightly upwards. This enables him to hold the marker close to his
face, as shown in FIG. 5, and can reduce even further the amount of
strain and bending of the wrist. Also because the curve of the
lower part 134a of the rear edge 134 of the grip 120 is
approximately centred on the lower trigger finger position, the
trigger fingers can still comfortably be held on the trigger as the
hand moves round the lower part of the grip.
[0043] As shown in FIG. 6A, with the marker held as shown in FIG.
5, the user can keep both of his elbows in close to his body while
holding the marker in the desired position. This means that the
user presents a small target to other competitors. If the user
moves the marker 110 away from his body and have his arms
substantially straight out in front of himself, particularly if
there is room for his hand to move up the grip 120, the palm of his
trigger hand rests more against the upper portion of the grip which
faces slightly upwards to the rear. This will tend to make the
marker feel more like a conventional marker and the angle of the
barrel will be relatively easy to keep under control. FIGS. 6B and
6C show the user of the marker 100 in a crouching and kneeling
position, respectively. A gas bottle 150 is typically disposed
below the marker 100, a source 160 of dye pellets positioned above
the marker 100 and the user wraps his arms around the bottle 150 in
selected positions, such as in the kneeling position of FIG.
6C.
[0044] Referring to FIG. 7, in a second embodiment of the invention
a grip frame 200, which could be used as part of the marker of FIG.
3 in place of the grip frame 114, includes a grip 202, a trigger
guard 204, and a cutlass 206. The upper part 208 of the grip has a
front edge 210 which is vertical, and the lower part 212 of the
grip also has front edge 214 which is vertical. The front edge 214
of the lower part 212, which is below the trigger guard 204, will
generally by held by the fingers of the user's trigger hand which
are not on the trigger, usually the fourth finger and little
finger. The trigger hand supporting rear edge 216 of the grip is
convexly curved and approximately symmetrical about a point S
approximately half way down it, where the rear edge 216 is
vertical. If tangents to this curve are made as shown at the
uppermost U and lowermost L positions on which the user could
centre his hand, it can be seen that these are inclined at about
100 to the vertical in opposite directions, and therefore inclined
at 200 to each other. The user can therefore change the angle of
his hand by approximately 20.degree. by moving it up and down the
grip 202. It can also be seen that the vertical distance h between
the two positions U and L is over a third of the vertical height y
of the grip.
[0045] Referring to FIG. 8, in a third embodiment of the invention
a grip frame 300 is similar to that shown in FIG. 4 except that the
trigger hand supporting rear edge 316 of the grip is straight and
vertical over the whole of its main central portion 316a which
takes up about 80% of the vertical height of the rear edge 316. The
rear edge 316 also has a small upper section 316b which takes up
about 10% of its height and is curved concavely upwards and to the
rear, and a lower section 316c at the bottom end of the grip 300
which curves convexly downwards and to the front.
[0046] Referring to FIG. 9, in a fourth embodiment of the invention
the grip frame 400 is again similar to that of FIG. 4 except for
the shape of the trigger hand supporting rear edge 416. The rear
edge 416 has a central portion 416a which is vertical and an upper
portion 416b which is inclined at about 20.degree. to the vertical,
facing upwards to the rear. There is also a lower portion 416c
which curves round from the bottom of the central portion 416a to
the under side 418 of the grip, and a top portion 416d which curves
to join the upper portion 416b to the base 428 at the top of the
frame 400. In FIG. 9 the two tangents T1, T2 to the rear edge 416
which are at 10.degree. to the vertical are shown, the upper one T1
being on the curve between the central and upper portions 416a,
416b, and the lower one T2 being on the lower portion 416c. It can
be seen that the vertical h height between the points where these
tangents touch the rear edge 416 is greater than a third of the
height y of the grip.
[0047] Referring to FIG. 10, in a fifth embodiment of the invention
a grip frame 500, which could also be used as part of the marker of
FIG. 3 in place of the grip frame 114, includes a grip 502, a
trigger guard 504, and a cutlass 506. The upper part 508 of the
grip has a front edge 510 which is vertical, and the lower part 512
of the grip also has a front edge 514 which is concavely curved.
The rear edge 516 of the grip is convexly curved at a substantially
constant radius of curvature, equal to approximately half the
length of the grip, which is about 50 mm. The curve is centred
approximately at the top of the front edge 514 of the lower part
512 of the grip, just below the trigger guard 504. This is the
position in which the fourth finger of the user's trigger hand
generally rests. Assuming the index and middle fingers are on the
trigger, the fourth finger provides a large proportion of the
support for the marker, and allowing the trigger hand to rotate
about that position as it moves up and down the grip enables the
user to keep a secure hold on the grip while his hand moves through
a large range of angles. The curve of the rear edge 516 extends
through an angle of about 120.degree., which therefore allows the
user to change the angle of the palm of his trigger hand through
more than 90.degree., from facing downwards at about 30.degree.
when resting on the top of the rear edge 516 of the grip 502, to
facing almost vertically upwards when resting at the very bottom of
the rear edge 516.
[0048] Referring to FIG. 11, in a sixth embodiment of the
invention, the grip frame 600 is identical to that of FIG. 7,
except for the shape of the rear edge 614 of the grip 612. In this
case the rear edge 614 is in two separate sections, an upper
section 614a and a lower portion 614b, each of which is straight.
The upper section 614a faces upwards being at an angle of about
10.degree. to the vertical, and the lower section 614b faces
downwards, being at an angle of about 20.degree. to the vertical.
This therefore provides two distinct hand positions for the user's
trigger hand which differ in angle by approximately 30.degree..
[0049] Referring to FIG. 12, in a seventh embodiment of the
invention, the grip frame 700 is identical to that of FIG. 7,
except for the shape of the rear edge 716 of the grip 712. In this
case the rear edge 716 has a lower portion 716a which is convexly
curved with its centre of curvature located approximately at the
position 754 where the user's fourth finger will rest, just below
the trigger guard 736 and behind the cutlass 737. The rear edge 716
also has an upper portion 716b, which is concavely curved and joins
the top of the lower portion 716a to the base 728 at the top of the
frame 700. The convex lower portion 716a takes up about two thirds
of the height of the grip 712, and the upper concave portion 716b
takes up about one third of the height of the grip 712.
[0050] Referring to FIGS. 13 and 14 a further method of measuring
how vertical the rear edge of a paintball marker grip will now be
described in relation to the to the grip 114 of FIGS. 3 and 4. The
grip side profile is generated which is equivalent to placing the
grip on its side on a shadowgraph and drawing around the projected
image to produce an external profile of the full grip frame. This
profile is then used for this analysis. The rear edge 116 of the
grip is defined as the rear face profile that the palm of the
user's trigger hand is intended to come into contact with such that
the fingers of the user's trigger hand can reach and operate the
trigger to fire the marker. One end of the rear edge 116 is defined
as the lowest point A of the grip which could be contacted by the
user's trigger hand, and the other end of the rear edge 116 is
defined as the topmost point B that can be contacted by the user's
trigger hand. The vertical height E of the grip 114 is defined as
the vertical distance between an upper X axis, which is a
horizontal axis level with the highest point B of the rear edge,
and a lower X axis, which is a horizontal axis level with the
lowest point A of the rear edge. In use there is generally a gas
bottle connected to the bottom edge 118 of the grip 114 which can
limit the ability of the user to place his hand in contact with the
lower end of the rear edge 116, but such restrictions are ignored
in this analysis and it is assumed that the whole of the grip is
accessible to the user.
[0051] A parallelogram or diamond shape is then constructed which
has four sides of equal length, two opposite corners on the upper
and lower X axes respectively, one vertically above the other, and
two other corners half way between the upper and lower X axes. The
diamond is constructed by drawing a vertical line between the two X
axes to produce two points of intersection C, D of the line and the
axes, drawing two lines upwards from the lower intersection point D
on opposite sides of the vertical and at 5.degree. to it, and two
lines downwards from the upper intersection point C on opposite
sides of the vertical and at 5.degree. to it. The two lines on each
side of the vertical meet half way between the two X axes to
produce two corners of the diamond.
[0052] Referring to FIG. 14, the diamond is then moved
horizontally, keeping its upper and lower corners vertically
aligned and on the upper and lower X axes until the rear edge 116
of the grip 112 intersects the sides of the diamond at at least two
points. The horizontal position of the diamond is then further
adjusted to maximize the vertical height of a single unbroken
length of the rear edge 116 that is within the diamond boundary.
For this shape of grip the final position of the diamond is as
shown in FIG. 14, with the curved central portion of the rear
surface 116 is just inside the rearmost side of the diamond, and
the rear surface 116 intersecting the two forward sides of the
diamond at points F and G.
[0053] The height of the section of the rear surface 115 that is
within the diamond is then measured by measuring the vertical
height H between the intersection points F and G. This height gives
an indication of how vertical the rear surface of the grip is. The
preferred value for this height H is at least one third of the
height E of the hand contacting rear edge 216 of the grip. However
in some circumstances it may be more preferable for the height H to
be at least one half, or even two thirds, of the height E of the
rear edge of the grip.
[0054] It can be seen that, using this analysis of the grip frames
of FIGS. 7 to 12 that the ratio of the height H to the height E is
approximately 2/3 for FIG. 7, 1/3 for FIGS. 8 and 11, 0.8 for FIG.
8 and 1/2 for FIG. 9 and FIG. 12.
[0055] Referring to FIG. 15, in an eighth embodiment of the
invention, the grip frame 812 includes a rearward projection 813
extending rearwardly from its lower end. The top surface 816c of
this projection 813 therefore forms the lowest point at which the
user's hand will contact the rear edge 816 of the grip at the lower
end of its rear edge 816. Therefore for this embodiment the height
of the trigger hand supporting rear surface 816 of the grip is the
vertical height y between the underside 816d of the rear of the
base 828 of the frame, and the top surface 816c of the rearward
projection 813.
[0056] The embodiments described can provide a paintball marker
which, when held in the position of FIG. 1 with the user's elbows
close to the body and the marker close to the user's face, creates
less strain on the user's wrist and allows more control over the
aiming of the marker.
[0057] It will be appreciated that various other shapes of grip
could be used which would provide different hand positions for the
user in a similar way to the embodiments described above.
* * * * *