Note: Descriptions are shown in the official language in which they were submitted.
Dkt. No. 35-OR-869
AUTOLOADIN& APP~RATUS FOR T~NK C~NNON
The present invention relates to armament
systems and particularly to apparatus for automating
the handling of large caliber ammunition for
turret-mounted cannons carried by armore.d vehicles,
suc~ as tanks.
Ba~kground of the ~ave~
Considerable efforts by armament
manufacturers throughout the world hava been devoted
to dsveloping automated appara~us for handling
ammunition for large field weapons. This is
~:; paxticularly so in the case of mobile direct-fire
wQapons carried by armored vehicles, ~uch as tanks.
Presently the tasks of withdrawing ammunition rounds
or sh~lls ~rom magazine storage and loa~ing them into
the ~re~ch o~ a tank cannon are almost universally
being a~complished manually~ A person per~orming the
duties of a gun loader is thus an e~sential member o~
.
:
, .
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Dkt. No. 35-OR 869
a military tank crew. To accommodate his movemen~ in
retrie~ing shells from a magazine and ramming them
into the cannon breech, considerable space must be
allotted for these activities within the tank, more
S t~pically within the revolving gun turret of the
tankO Adequate headroom should be provided ~o the
gun loader can work standing up. Unfortunately, this
increases the vertical profile of the tank and thus
its size as a target to hostile fir~, The turrat
must, therefore, be heavily armoxed to maximize tank
and crew survivability against enemy ~ire. Of
course, heavy armor plating adds tremendously to the
weight: of a tank, which tllen requires a larger power
pack, drive train, and suspension.
The ~actors of gr~ater overall profile and
the conse~uences thereof, the elimination of a gun
loader and the consequent space saving~, and the
prospect o~ higher firing rates have heretofore ~een
the primary motivations for developing a satisfactory
autoloader ~or tank cannons~
O~ the numerous autoloaders seen in the
prior ark, most are highly complex, extraordinarily
space-consuming, difficult to maintain and
susceptible to frequent mal~unction. Many of the
existing designs require that the cannon return to a
predetermined position, particularly in elevation,
before automated loading can be ef~ected. Thus, the
cannon must be repeatedly removed from the target ~or
reloading and returned ~or firing, a signi~icant
detriment to firing rate.
207~a:LO
Dkt. No. 35-OR-869
Summary of the Invention
In accordance with the present invention,
there is provided improved apparatus for feeding a~d
loading a~munition rounds or shells into a tank
cannon without human intervention. The autoloader
apparatus o~ the invention operates to retrieve
cannon shells from a magazine, convey ~he ~hells to
the cannon and ram them into the cannon breech, all
on an automated basis. The autoloader is of an
extremely compact construction to operate within an
extraordinarily small space envelope. Positive
control of each shell is maintained throuqhout the
process to ensure reliable handling while the tank is
travelling over rough terrain. The capability of
loading the cannon regardless of its position in
azimuth and elevation provides for a signi~icant
improvement in firing rate. Mo.reover, ~he autoloader
of the present invention perinits retrieval of a shell
from a magazine with a previously loaded shell in the
. canno~ breech and ready to fire, thus permitting the
: step of transferring a shell from the magazine ~o the
cannon to be conducted at a reduced pace, ther~by
minimizing autoloader power requirements without
jeopardizing ~iring rate.
Brief Description_of the Dr~
For a full understanding of the nature and
objects of the invention, reference may be had to the
following Detailed Description taken in conjunction
with the accompanying drawings, in which:
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Dkt. No. 35-OR 869
--4--
FIGURE 1 is a perspective view, partially
broken away, of an armored vehicle equipped with an
overhead gun served by automated ammuni~ion loading
appaxatus constructed in accordance with one
emhodiment of the present invention;
FIGURE 2 is a simplified side ~levational
view, partially broken away, schematically
illustrating in phantom the articulation of a shell
achieved by the autoloading appar~tus of FIGURE 1
during mov~ment between an ammunition storage
magazine and the gun;
FIGURE 3 is a simplified side elevational
lS view illustrating the a.utoloading apparatus of FIGURE
1 in its latched magazine position;
FIGURE 4 is a simpli~ied side elevational
~iew illustrating the autoloading apparatus of FIGURE
1 in a position between the magazine and gun loading
positions:
FIGURE 5 is a fragmentary side elevational
view illustrating the ~rolley and rammer in their
relative positions when th~ autoloading apparatus o~
~IGUR~ 1 assumes its gun loading positiont
FIGURE 6 is an rear end v.iew, partially in
section, of the rammer o~ FIGURE 1;
FIGUR~ 7 is a perspective view of the rear
stage of the rammer of FIGURE 6:
.
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2~7~
Dkt. No. 35 OR-869
FIGURE 8 is a magnified perspective view of
a portion of the rear rammer stage of FIGURE 7;
FIGURE 9 is a fragmentary plane view
illustrating details o~ the forward stag~ of the
rammer;
:FIGU~ES 10 and 11 are fragmentary plan
views in time line relation to illustrate the
trans~r of a shell from the rear to the forward
rammer stages;
FIGURE 12 is a perspective view, partially
broken away, of a military tank equipped with
automa~ed loading apparatus constructed in accordance
with an al~ernative embodiment o~ the present
inv~ntion;
FIGURE 13 is a sid~2 elevational view,
partially broken away, of th~ autoloading apparatus
of FIGURE 12;
~ ~ .
FIGURE 14 is a plane view o~ the
autoloading apparatus of FIGURE 12, seen in its
cannon loading position;
FIGURE 15 is a side view similar to FIGURE
: ~13 illustrating the capability of the autoloading
apparatus of FI~URE 12 t~ access ammunition magaZines
located in rearward hull and turret bustle s~orage
area~; and
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Dkt. No. 35-OR-869
FIGU~ES 16 and 17 are side views, partially
in longitudinal section, of a rammer included in the
autoloadin~ apparatus of FIGU~E 12 and illustrating
respective retracted and extended conditions thereof.
Corresponding reference numerals refer to
like parts throughout the sevçral views o~ the
drawings.
Detailed Description
The autoloading apparatus in accordance
with one embodiment of the present invention,
generally indicated at 20 in FIGURE 1, is illustrated
in its application to an armored vehicle or tank 22
having a revolving turret, generally indicated at 24,
whose roof 26 is essentially flush with the tank deck
28. Supports 30, upstanding from the turret roof,
mount, via trunnions 34, an overhead cannon or gun 32
for azimuthal movement with the turret and
i~dependent elevational movement about the trunnion
axi~. A~fixed to the gun in enclosing r~lation with
its breech end 36 is an armored weapon pod 38 having
a chut~ 40 communicating the pod interior with the
turret interior or basket through a turr~t opening 42
~FIGURE 2). Autoloader 20 includes a trolley 44
equipped to run in opposed, arcuat~ guide tracks ~6
mounte~ to sidewalls of chute 40; the guide tracks
having a constant radius of curvature centered on the
gun elevation axis constituted by the trunnions. The
trolley mounts a rammer 48 for engagingly controlling
a shell 50 through a feedpath illustrated in F~GURE 2
"` 2~7~
Dkt. No. 35-OR 869
during trolley movement along the guide tracks
between a gun loading position illustrated in FIGURE
1 and a magazine position illustrated in FIGURE 3.
In the gun loading po~ition, the rammer i~ oriented
to align the shell with the gun boreline so that it
can ~e rammed into breech 36 by the rammer. In the
magazine position releaseably ~ixed to the turret by
a ~olenoid actuated latch 51 (FIGU~E 4), the rammer
is oriented to acquire c~ntrol of and retrieve a
shell from a rotating drum magazine 52 presented by a
tilted up tube 54 when oriented in the twelve o'clock
- position by a suitable drive mechanism ~not shown).
Th~ magazine is tied to the turret basket floor and
~hus moves with the gun and autoloader in azimuth.
FIGURE 3 illustrates that, while the
autoloader is in its latched magazine position,
changes in gun elevation do not affect the positional
relationship of the autoloader and magaæine; the
guide tracks simply sweeping past the autolaader as
the gun el~vate~ and depresses. When the autoloader
is latch~d to the weapon pod in its ramming posi~ion
of FIGU~E 1 by a solenoid actuated latch 53 (FIGU~E
4), the trolley and rammer move with the gun in both
azimuth and elevation. Intermediate these latched
positions, th~ autoloader simply moves in the guide
tracks as they ~ollow changes in gun elevation. It
~` will be noted that the length of the fead path varies
with gun elevation. As is apparent from FIGURE 3, at
zero el~vation the ~eed path between the magazine and
gun is significantly longer than at an elevated
position, such as a plus 18 elevation. It is thus
~7~0
Dkt. No. 35-OR-869
seen that autoloader 20 is capable of per~orming the
steps of retri~ving shells from magazine storage,
feeding them to the gun and ramming tham into the
breech, all while the gun is at any elevation or
while the gun is being elevated and depressed.
Autoloader 20 is thus capable of a high ~iring rate.
To execute the maneuver illustrated in
FIGURE 4 of articulating rammer 48 and its shell 50
out of the open upper end of chute 40 into ramming
po~ition within pod 38 aft of the gun breech
consistent with the imposed space limitations, the
rammer is pivotally mounted to trolley 44. Ref~rring
to FIGURE 5, the trolley mounts two opposed sets of
three guide rollers 56a, 56b and 56c, which run in
the two guide tracks 46. Thl. pair of opposed rollers
56c are mounted on a cross shaft 57 which, as seen in
FIGURE 4, serves as an axle pivotal mounting the
rammer to the trolley. The rammer mounts a pair of
opposed guide rollers 58 which also run in the guide
traGks until the start of the pivot maneuver when
they exit the upper ends o~ the tracks. On2 end of a
trollPy link 60 is pivotally connected to the trolley
at 60a, while its other end is pivotally connected to
one end of a rammer link 62. Th~ pivotal c~nnection
o~ ~hese two links also serves to mount a trolley cam
roller 64 riding on a cam surface 66 provided by the
inner wall of one of the guide tracks. ~he other end
of link 62 is pivotally connected to a rammer control
arm 68 provided as a rigid extension of the rammer.
2~511 ~
Dkt. No. 35-OR-869
FIGURE 5 shows trolley 44 in its gun
loading position with rammer 4~ pivoted away to its
rammin~ position, it is seen that cam roll2r 64 has
been diverted from cam surface 66 into a cam track 70
S diverging inwardly away from one o~ the guide tracks
46. This is seen to articulate links 60 and 62 such
as exert a moment on rammer control arm 68 to produce
controlled pivoting motion o~ the rammer about cross
sha~t 57 in the illustrated clockwise direction.
Note that rammer guide rollers 58 have exited the
upper ends of the guide tracks to free the rammer for
this pivoting motion progressively into its ramming
positlon as cam roller 64 runs up in cam track 70.
1~ To propel the trolley 44 along it5 guide
tracks 46, an electric motor 74, mounted to the
trolley ~rame as seen in FIGURE 1, drives a pair of
~ output pinions 76 which engage sector gear 78 formed
: in the outer walls of the two guide tracks 46. These
dual output pinions 76 are commonly driven by the
motor in meshing engagement with the two guide track
sector gear~ 78 to produce smooth, non-~inding motion
in the guide tracks. The output pinions are
pexmitted to free-wheel when the trolley is latched
in either of its magazine and gun loading positions
to accom~odate movements of the sector gear and guide
tracks with elevational motion o~ the gun.
Rammer 48 includes, as seen in FIG~RE 6, a
generally tubular housing consisting of an upper half
and a lower half united by bolts 99. The upper
housing half is formed with lateral extensions 100
Dkt. No. 35-OR-869
--10--
for mounting at their ends the rammer guide rollers
58 also seen in FIGURE 5, which run in guide tracks
46 prior to the rammer pivoting motion. The housing
also mounts a pair of longitudinally spaced sprockets
102 about which an endless chain 104 is trained, as
seen in FIGURE 9. An electric motor 106 (FIG~RE 6),
mounted by the rammer housing, drives the forward
sprocket to power two rammer stages. The tubular
portion 109 of the rammer housing is sized to receive
a shell in close fitting rel~tion to provide support
and guidance therefor.
As seen in FIGURE 7, rammer 48 includes a
rear rammer stagP, generally indicated at 110, having
a base 11~ and a pair o~ forwardly extending rails
114a and 114b which are slidingly received in
trackways 116 formed in lowe:r housing hal~ 98b
(FIGURE 6). The base providles underlying support for
the case rim of a shell and also serves as a ramming
element propelling the shell toward the gun breech.
As seen in FIGURE 8, adjacent the junction of rail
114b with base 112, an extractor pawl 118 is
pi~otally mounted with its tip 118a biased inwardly
by a spring 120 to catch the ~ront edge of the case
rim 50a o~ a shell 50 residing in the tubular rammer
housing. The case rim is thus captured between t~e
pawl tip and base 112 to positively control the shell
position during shell-f~eding autoloader mavement
between ~ts magazine and gun positions and rammer
pivotal movement into its ramming position. As seen
in FIGURE 7, an accelerator link 122 is pivotally
mount~d by a pin 123 to the forward end of rail 1~4b
o
Dkt~ No. 35 OR-869
11--
and is provided with a pair of notches 122a and 122b,
the latter positioned when the link is swung away
from rail 114b to pick up a drive pin 134 (FIGURE 93
carried by chain 104. As the drive pin moves with
the inner chain run toward the rear sprocket, which
occurs during trolley motion toward its gun loading
position at a time when space is available in the
chute and weapon pod, the rear rammer stage is driven
rearwardly from its phantom line nested position in
the rammer housing to its solid line extended
position seen i~ FIGURE 5. once the rear rammer
stage reaches its ~ull rearward extension, the rammer
: motion îs halted with drive pin 134 still latched in
the accelerator link notch 122b to await the call for
a ramm.ing stro~e. The rear rammer extractor pawl 118
of FIGURE 8 ensures that the shell follows the rear
rammer stage to its extended position.
The underside~ of the rails are ~ormed with
2U rack gears 124 which mesh with spur gears 126 keyed
to the ends of a cross sha~t 128 journalled by the
~: lower rammer housing half . rrhus , driving power
applied by chain ~04 to strolce the rear ramm~r stage
is distributed equally to the rails via these spur
and rack gears to assure smooth, non-binding motion.
The ~orward ra~ r stage consists o~ a
ex~ractor pawl 130 and a rammer pawl ~32 pivotally
mounted by chain 104 in proximately spaced relation,
as se~n in FIGURE 9. These pawls ar~ spring biased
outwardly to posi~ion their tips in closely
~traddl~ng:relation with the case rim 50a of a shell
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Dkt. No. 35-OR-869
-12-
50 residing in the tubular ra~mer housing. When the
chain i~ driven in the clockwise direction, such
that it~ inner run proximate the shell is moving
rearwardly (rightward in FIGURE 9~, extractor pawl
130 swings around the forward sprocket 102 to catch
the forward edge of the case rim and propel the shell
rearwardly toward the rear rammer stage in its
telescoped foxward position. It will be appreciated
that rammar pawl 132 .is depressed by the shell rim as
it swings around the forward sprocket i~ advance of
the extractor pawl. This operation occurs when the
autoloader is in its magazine position to retrieve a
shell ~rom magazine 52 as described in ~onnection
with FIGURE 3.
When chain 104 is driven in the opposite
direction, such that its inner run is moving in the
forward direction, extractor pawl 130 is depressed by
the shell rim as it swings counterclockwi~e around
the re~r sprocket, clearing ~the way for rammer pawl
132 to catch the rear edge of the cas rim and
propel the shell forwardly. This action occurs
dur~ng the ~orward stroke of the forward rammer
s~age, which is the second half of the ramming stroke
to propel the shell into the gun breech: the forward
strok~ of the rear rammer constituting the ~irst hal~
o~ the ramming stroke. FIGURE 9 also shows the
relationship of pawls 130 and 132 to the rear rammer
stage drive pin 134 carried by chain 10~.
The smooth transfer or handoff of the shell
from the rear rammer stage to the forward rammer
Dkt. No. 35-oR-a69
-13-
stage when the second half of the ramming stroke
takes over from the first half is illustrated in
FIGURES 10 and 11. At the moment forward rammer pawl
132 swings counterclockwise around the rear sprocket
S to take ov9r ~orward driving engagement with the case
rim 50a from base 112, the tip 118a of the rear
extractor pawl is being swung away from the case rim
by engagement of the rear extractor pawl with a cam
surface 142 fo~med on the rammer housing 98. At the
same time, drive pin 134 swings counterclockwise
around the forward sprocket, bringing with it the
accelerator link. The rear rammer stage is thus
smoothly decelerated from the chain speed to a stop
as drive pin disengages from accelerator link notch
122b.
The handoff of a shell from the forward
rammer stage to the rear rammer stage during the
magazine loading step is effe!cted basically in a
reverse manner. The drive pin picks up the
: acc~lerator link to accelerate the rear rammer stage
up to chain speed. Upon achieving chain speed, whi~h
is slower than the chain speed during the ramming
strok~, the rear extractor pawl is in position
relative to the front edge of th~ case rim to take
over shell retraction from the front extractor pawl
as it 6tarts around the rear sprocket and swings away
from the case rim. Thus, the shell is smoothly
handed off from the front rammer stage to the rear
rammer stage to complete retrieval of a shell from
the magazine. Typically, the rear ramm~r stage ~ill
only execute a partial rearward stroke sufficient ~o
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Dkto No. 35-OR-869
--14 ~
acquire positive control of the shell and to clear
the shell from the tilted up ma~azine tube (FIGURE
3). This rearward s~roke is completed when space
becomes available during the shell transfer step.
s
When the shell is released by the ramming
pawl of the ~ront rammer stage to conclude the
forward stroke of the rammer, the shell casing has
sufficiently entered the gun bore to permit the shell
to coast into its fully loaded position, in the
process triggering the breech mechanism extractors to
initiate breech closure. To ensure shell alignment
as it coasts ~rom the front rammer stage into the gun
breech, the rammer incorporates a guide tongue 146
seen in FIGURE 5. The guide tongue is slidingly
received in a keyway 148 formed in lower rammer
housing hal~ 98b (FIGU~E 6). The underside of the
guide tongue is machined to provide a rack gear 150.
When the rammer is pivoted illtO its ramming position
~0 in reaction to cam roller 64 moving into cam ~rack 70
(FIGURE 5), the swinging motion of a sector gear 164
drives the guide tongue forwardly to an extended
position via an interconnecting gear train (not
shown~. When the rammer pivots back to its clo~ed
position with respect to the trolley as the
autoloader departs it~ gun position, the sector gear
swings in the opposite direction to retract the guide
tongue to its telescoped, stowed position within the
. rammer hou~in~. In addition ~o aligning a shell
durin~ the ramming step, the guide tongue serves to
~uide a.previously committed shell as it is ejectad
back out to the ~irst rammer stage. ~ bu~fer (not
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Dkt. No. 35-OR-869
shown) is incorporated in the rammer to absorb the
impact of the ejected shell and bring it t4 rest
within the rammer tube. The rammer stages then
operate in the same manner as when retrieving a shell
from the magazine to position the shell on the rammer
for movement back to the magazine. The ra~mer then
executes a slow speed ramming stroke to return the
shell to magazine storage.
In an alternative embodiment of the prssent
invention, an autoloading apparatus, generally
indlcated at 210 in FIGURE 12, is illustrated in its
applic:ation to an armored vehicle or tank 212 having
an armored turr~t, generally indicated at Zl4, which
is mounted to the tank deck 16 via bearings 217 ~or
azimuthal revolving movement;. The turret, in turn,
mounts a cannon 218, via tnmnions 220, ~or
independent pivotal movement: in elevation.
Autoloading apparatus 210 is also mounted to the
~0 turret and contained by the turret basket 222. The
autoloading apparatus includes a tralley 224 which is
controlled in vertical movement by a pitch and roll
guide track 226 and yaw guide track 228. As seen in
~ FIGURE 13, these guide tracks are anchored at their
: 25 lower ends to the basket floor 229 and at their upper
ends to the turret roof 230. Guide track 226
includes a straiqht lower vertical section 226a which
blends into an arcuate upper vertical sec~ion ~26b.
The arcua~e section has a constant radius o~
; 30 curvature centered on the cannon elevation axis
constituted by trunnions 220. Similarly, guide track
223 includ~s a straight low~r vertical section 228a
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Dkt. No. 35-OR-869
-16-
blending into an arcua$e upper vertical section 228b
whose constant radius of curvature is also centered
on the cannon elevation axis.
As best seen in FIGURE 13, trolley 224
rotatably mounts a pair of vertically spaced rollers
232 at its forward end, which run in a channel-shaped
guideway 234 of guide track 226 to control pitch
motion of the trolley during its vertical movement.
Just rearwardly o~ the rollers, the trolley mounts a
pair of vertically spaced guide blocks 236 provide~
with grooves 237 to receive in close~fitting, sliding
relation a continuous~ rearwardly turned rim 238
(FI~UR~ 14~ of track 226. The rim-engaging guid~
blocks preclude rolling motion of the trolley during
vertical movement. To prevent yawing motion of the
trolley, it is equipped at i1:s rearward end with a
singl2 guide block 240 which is grooved at 241 to
receive in close-fitting, sliding relation a
~orwardly turned ~lange 242 of guide track 228. To
propel vertical movement of the trolley, an electric
motor drive unit 24~ is pivotally mounted to the
basket floor 229 by a bracket 245. The drive unit
turns an elongated ball screw 2~6 extending upwardly
between guide tracks 226 and 228 to a free end
terminating just short of the turret roof 230, as
seen in FIGURES 12 and 13. Meshing with this ball
screw is a ball nut 248 pivotally mounted to the
trolley. From the description thus far, it is seen
that bidirectional rotation of the ball screw by the
motor drive unit propels the trolley up and down the
guide tracks, with the ball screw swinging on its
2~)7~5~
Dkt. No. 35-OR-869
-17~
lower end pivotal mounting to the basket ~loor and
the ball nut turni~g on its pivotal mounting to the
trolley to accommodate articulation of the trolley as
it moves along the straight and arcuate sections of
the guide tracks.
Mounted to the trolley is a rammer 250
eguipped to extract ammunition rounds from storage
tubes 252 o~ a magazine, generally indicated at 254.
The magazin~ includes a carousel conveyor (not shown)
operating to bring a storage tube containing a
selectsd ammunition round to a predetermined
unloading position shown in FIGURE 13.
It will be appreciated that, hy ~irtue of
the arcuate guide track sect.ions being located on
recpective radii with the cannon elevation axis,
loading ~an be accomplished regardless of the angle
in elevation ox depression the cannon is positioned
to. Moreover, the steps of retrieving an ammunition
round from the magazine and trans~erring the xound
toward the cannon breech may be ongoing with the
cannon at any position or while elevating or
depressing. Not~ that the length of the round
transfer path ~rom magazine to cannon breeah varies
with cannon ~levation. Thus, au~oloader ~10 has the
same capabiliti~s as au~oloader 20 o~ FIGURE 1 to
a~ord a dramatic increase in firing rate as compared
to prior art autoloaders.
~7~ 0
Dkt~ No. 35-OR~869
-18-
As illustrated in FIGURE ~4, rammer 250 is
rotatably mounted to trolley 224 by an axle indicated
at 256. The trolley carriers a motor ~58 which
drives, via a pinion gear 259, a spur gear 260
af~ixed to the rammer in concentric relation with the
axle to rotate the rammer end for end. This faculty
enables the rammer to retrieve rounds from ammunition
magazines 262 and 264 located in a hull storage area
and a bustle storage area, respectively, as
illustrated in FIGURE 15. To access magazin~ 262 in
the hull storage area, trolley 224 is driven to a
lower p~sition with its rollers 232 in th~ portion of
trackway 234 in straight section 226a, thus
positioning the rammer in an essentially hori~ontal
orientation. This trolley position may also be
utilizad to access turret magazine 254, if oriented
horizontally rather than tilted downwardly as
illustrated in FIGURE 13. It will be appreciated
that, ~ince hull storage magazine 262 does not
revolve with the cannon, the turret will have to be
located i~ a predetermined azlmuth position to enable
the rammer to retrieve rounds therefrom. This
limitation, of course, does not apply when retrieving
rounds from the turret and bu~tle magazines. A
solanoid latch 266, seen in FIGURES 13 and 14, serves
to r~leaseably lock the rammer to the trolley in
requisite pitch position for ramming an ammunition
round into the cannon breech and for extracting
rounds from a magazine.
Rammer 250, as detailed in FIGURES 16 and
17, includes a housing generally indicated at 268
.
2~7~10
Dkt. No. 35-OR-869
~19-
having an elongated rammer tube 270 for slidingly
receiving an ammunition round in the form of a
projectile 272 for cannon 218 configured as a liquid
propellant gun. A rammer head 274 is also slidingly
received in the rammer tube and is shown in it~
retracted position in FIGURE 16. The lower portion
of the rammer tube opens into a trough in which are
formed opposed guideways 278 for receiving laterally
extending guides 280 of a slider generally indicated
at 282. A pair of upstandin~ slider arms 284 carry
between its upper ends a shaft 285 for journalling a
sprocket 283. The lower portion of the slider is
threaded ~o provide a ballnut 290 in meshing
engagement with a ballscrew 292 extending through the
trough and journalled at its forward end by bearing
294 mounted by the housing 268, as seen in FIGURES 16
and 17. An electric motor 296, caxried by the rammer
housing as seen in FIGVRE 14, drives the ballscrew
via a spur gear 298 keyed to its forward end to
reciprocate slider 282 paral:lel to the axis of the
rammer tube 270.
A stiff-backed chain 300 is pinned at its
~orward end to the housing, as indicated at 301, and
extends rearwardly through the housing trough and
arbund sprocket 288 to its rearward end pinned to
ra~mer head 274, as indicated at 302. The portion of
the chain in th~ trough is ba~ked by an elongated
channel-shaped support 304 moun~ed in the ~rough by
pin~ 301 and 303 and extending between the slider
a~ms. The characteristic of a stiff-backed chain is
~hat its links will readily pivot in only one
2 ~ 7 ~
Dkt. No. 35-OR-869
-20-
direction. Thus, chain 300 can pivot inwardly to
train around sprocket 288, but will not say
outwardly. Thus, a linear section will remain stiff
to serve as a linear drive element as long as it is
backed against outward bu~kling movement.
A~ seen in FIGURE 16, a solenoid actuated
gripper 306 is carried at the face of rammer head 274
~or releaseably engaging a handling plug 308 provided
at the tail end of the projectile 272. A cable 310
is threaded through stiff-backed chain 300 ~or
electrically actuating gripper 306 to grip and
releas~ handling plug 308 as required.
From the foregoing description of rammer
250, it is seen that, with rammer head 274 in its
retracted position o~ FIGURE 16, forward rotation of
ball screw 292 by motor 296 propels slider 282
forwardly. The slider sprocket 288 rolls on the
portion of chain 300 in trough 276, causing chain end
302 pinned to rammer head 274 to move forwardly away
from the sprocket. Sinca the chain is backed by
rammer tube 270, it remains stiff to prop~l the
rammer head forwardly at twice the forward speed of
th~ slider as the chain length between th~ sprocket
a~d rammer head increases. FI~URE 17 shows slider
282 in its ~orwardmost position and rammer head 274
fully extended by stiff-backed chain 300 out of the
forwar~ end o~ rammer tube 270 and into bree~h 218a
to load projectile 272 into ~he cannon. ~ripper 306
is then released, and the ballscrew is driven in the
reverse direction to draw the rammer back to its
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Dkt. NoO 35-OR-869
-21-
retracted position of FIGURE 16. Note that the
rammer head has sufficient axial length to bridge the
gap between the rammer tube and the breech bore and
thus positive guidance of the rammer head during this
transition is maintained. As the rammer head ext~nds
to its ~ully extended position to ram the projectile
home, backing for the stiff-backed chain is provided
by the breech bor~.
To retrieve a projectile from a magazine
storage tube 252, the rammer head is propelled
forwardly out of the rammer tube and into th~ storage
tube in the same manner as or a ramming stroke. The
gripper 306 is actuated to grip the projectile
handling plug 308, and the rammer head is drawn back
to its position of FIGURE 16, pulling the projectile
out of the storage tube and into the rammer tube
where it is held under positive control during
movement along the transfer path to the troll~y
loading po~ition, as well a~ during end-for ~nd
rotation of the rammer by motor 258 (FI~RE 14) after
retrie~al of a projectile from bustle and hull
storage magazines. In the same manner that a
projectile is retrieved ~rom one of the various
~agazines and loaded into the cannon, the autoloading
appara~us o~ the invention can be controlled to
retrieve a committed, but unfired projectile from the
cannon breech and return it to magazine st~rage.
It is from the foregoing that the
objectives s~t forth, including those made apparent
~rom th~ De~ailed Description, are e~ficiently
.
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Dkt. No. 35-OR-869
attain~d, and, since certain changes may be made in
the construction s~t f orth without departing ~rom the
scope of l:he present invention, it is intended that
matters of detail be taken as illustrative and not in
a 1 imiting sen~;e .
