Note: Descriptions are shown in the official language in which they were submitted.
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APPARATUS FOR RAISING A SOW IN A FARROWING CRATE
This invention relates to an apparatus for raising a sow in a farrowing
crate relative to a floor for the piglets for reducing piglet mortality by
crushing as the
sow lies or treads during movement to access feed and water.
BACKGROUND OF THE INVENTION
In British patent 932189 (Hodgkinson) issued in 1963 is shown a
farrowing crate or pen for sows where the level of the outer floor section
which
carries the piglets can be raised and lowered in order to move the piglets
away from
danger from the sow when the sow is standing, Thus when the sow lies down, the
piglets are kept away from the height of the floor level on which the sow lies
to
reduce the possibility of crushing.
This arrangement uses a light beam and electric switches to detect the
movement of the sow and uses a complex Iifting arrangement. The device is
currently not available on the market.
U.S. Patent 4,793,287 of Hoffmann issued in 1988 discloses a
modified arrangement in which Iifting and lowering of the piglet floor section
is
actuated by an alternative arrangement. However again this construction is
disadvantageous and is not available in the market place.
In German Application DE 43 20 345 (Ulrich) published 22"d December
1994 is disclosed a farrowing pen with a base frame which is laid on a floor
with an
air bag carried on the base frame which can be actuated to raise a sow support
floor
section mounted on top of the base frame on levers which swing the floor
section
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longitudinally and upwardly. The lifting action is controlled by a valve which
actuated
by the sow lying down on the valve or standing up from the valve.
In European Application 360 308 (Geerkens) published 280 March
1990 is disclosed a farrowing pen with a lift frame mounted over a sow support
floor
section for lifting the floor section upwardly on two motors and associated
screws,
one at each end. The lifting action is controiled by a photo-electric cell
which detects
lying or standing of the sow.
SUMMARY pi= THE INVENTION
It is one object of the present invention, therefore, to provide an
improved apparatus for raising and iowering a sow in a farrowing pen.
According to one aspect of the invention there is provided a farrowing
pen for sows comprising:
a pit for manure having a pit floor and pit sides with side floor portions
above the pit on each side of the pit;
a floor assembly for receiving the sow and piglets which includes a first
floor portion on which the sow can stand and lie and two second floor portions
each
on a respective side of the first floor portion for receiving piglets of the
sow;
the first floor poraon and the two second floor portions being arranged
to span the pit;
confining walls for locating the sow on the first floor portion;
a support element for the first floor portion;
the support element including a base member and a lift mechanism
carried on the base member, operated by a power source, arranged to raise and
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lower the first floor portion relative to the base member between a lowered
position
in which the first floor portion is at a generally common height with the
second floor
portions to allow the piglets to access the first floor portion and the sow
thereon and
a raised position in which the first floor portion is at a height above the
second floor
portions sufficient to prevent the piglets on the second floor portions from
accessing
the first floor portion;
and a sensor responsive to movement of the sow tending to stand to
actuate the lift mechanism to operate the lift mechanism;
the support element comprising a frame mounted on each of the side
floor portions on respective sides of the pit so as to span the pit;
the frame being mounted so as to extend undemeath the first floor
portion;
the frame supporting the base member therefrom at a position
underlying the first floor portion and overlying the pit such that the base
member is
free from support from the floor of the pit.
Preferably the base member is carried on the frame so as to be
suspended underneath the frame.
Preferably the base member is located at a height within the pit and
below the side floor portions.
Preferably the support element carries a guide system for guiding
vertical movement of the first floor portion and for maintaining the first
floor portion
horizontal.
Preferably the guide system is carried on the base member.
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Preferably the guide system comprises two pairs of levera arranged in
a scissors arrangement with each pair on a respective side of the first floor
portion.
Preferably the lift mechanism comprises an inflatable air bag carried on
the base member between the pairs of levers.
Preferably the lift mechanism comprises an inflatable air bag carried on
the base member with the guide system.
According to a second aspect of the invention there is provided a
farrowing pen for sows comprising:
a pit for manure having a pit floor and pit sides with side floor portions
above the pit on each side of the pit;
a floor assembly for receiving the sow and piglets which includes a first
floor portion on which the sow can stand and lie and two second floor portions
each
on a respective side of the first floor portion for receiving piglets of the
sow;
the first floor portion and the two second floor portions being arranged
to span the pit;
confining walls for locating the sow on the first floor portion;
a support element for the first floor portion;
the support element including a base member and a lift mechanism
carried on the base member, operated by a power source, arranged to raise and
lower the first floor portion relative to the base member between a lowered
position
in which the first floor portion is at a generally common height with the
second floor
portions to allow the piglets to access the first floor portion and the sow
thereon and
a raised position in which the first floor portion is at a height above the
second floor
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portions sufficient to prevent the piglets on the second floor portions from
accessing
the first floor portion;
and a sensor responsive to movement of the sow tending to stand to
actuate the lift mechanism to operate the lift mechanism;
5 the support element comprising a frame mounted on each of the side
floor portions on respective sides of the pit so as to span the pit;
the frame being mounted so as to extend underneath the first floor
portion;
the frame supporting the base member therefrom at a position
underlying the first floor portion and overlying the pit such that the base
member is
free from support from the floor of the pit;
a guide system for guiding vertical movement of the first floor portion
and for maintaining the first floor portion horizontal;
wherein the base member is carried on the frame so as to be
suspended underneath the frame;
and wherein the base member carries the lift mechanism and the guide
system.
Preferably the base member is located at a height within the pit and
below the side floor portions.
Preferably the guide system comprises two pairs of levers arranged in
a scissors arrangement with each pair on a respective side of the flrst floor
portion.
Preferably the lift mechanism aomprises an inflatable air bag carried on
the base member between the pairs of levers.
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According to a third aspect of the invention there is provided a
farrowing pen for sows comprising:
a pit for manure having a pit floor and pit sides with side floor portions
above the pit on each side of the pit;
a floor assembly for nrceiving the sow and piglets which includes a first
floor portion on which the sow can stand and lie and two second floor portions
each
on a respective side of the first floor portion for receiving piglets of the
sow;
the first floor portion and the two second floor portions being arranged
to span the pit;
confining walls for locating the sow on the first floor portion;
a support element for the first floor portion;
the support element comprising a frame mounted on each of the side
floor portions on respective sides of the pit so as to span the pit undemeath
the first
floor portion and a base member carried by the frame underlying the first
floor
portion and overlying the pit such that the base member is free from support
from
the floor of the pit;
the support element including a gas bag lift mechanism carried on the
base member, operated by a compressed gas source, arranged to raise and lower
the first floor portion relative to the base member between a lowered position
in
which the flrst floor portion is at a generally common height with the second
floor
portions to allow the piglets to access the first floor portion and the sow
thereon and
a raised position in which the first floor portion is at a height above the
second floor
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portions sufficient to prevent the piglets on the second floor portions from
accessing
the first floor portion;
a sensor responsive to movement of the sow tending to stand to
actuate the lift mechanism to operate the lift mechanism;
and a guide system carried on the base member for guiding vertical
movement of the first floor portion and for maintaining the first floor
portion
horizontal.
Preferably the base member is located at a height within the pit and
below the side floor portions.
Preferably the guide system comprises two pairs of levers arranged in
a scissors arrangement with each pair on a respective side of the first floor
portion.
BRIEF DESCRIPTION OF THE DRAWfNGS
One embodiment of the invention will now be described in conjunction
with the accompanying drawings in which:
Figure 1 is a side elevational view through a farrowing pen showing the
lifting apparatus according to the present invention showing the sow lift with
the sow
floor portion in the raised position.
Figure 2 is a rear elevational view of two farrowing pens of Figure 1
arranged side by side.
Figure 3 is a side elevational view similar to that of Figure 1 showing
the sow lift mounted directly on the barn floor and with the sow floor portion
in the
raised position.
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Figure 4 is a top plan view of a portion only of the farrowing pen of
Figure 1 showing the actuating valve.
Figure 5 is a cross sectional view along the lines 5-5 of Figure 4
showing the actuating valve.
Figure 6 is a longitudinal cross sectional view of a second embodiment
of a sow lift mechanism according to the present invention.
Figure 7 is an isometric sketch of a third embodiment of a sow lift
mechanism according to the present invention.
Figure 8 is a longitudinal cross sectional view of the embodiment of the
sow lift mechanism of Figure 3 in the lowered position of the sow floor
portion.
Figure 9 is a top plan view the second embodiment of a sow lift
mechanism of Figure 3.
In the drawings like characters of reference indicate corresponding
parts in the different figures.
DETAILED DESCRIPTION
In Figures 1 to 5, 8 and 9 is shown the construction of the present
invention somewhat schematically showing the operation of the device and the
basic
construction of the device.
A farrowing crate thus comprises a first floor section 10 for receiving
the sow. The floor section 10 can be formed from many different types of
flooring all
of which are presently commercially available including plastics flooring,
cast iron
flooring and flooring of plastics coated metal. The floor section has a width
and
length sufficient to receive the sow and is in some cases formed from panels
which
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are arranged end to end to form the complete floor section. On each side of
the first
floor section is provided two second floor sections 11 which are arranged for
receiving the piglets. The characteristics of the floor therefore are
significantly
different and they may include heating pads and the like to properly pravide
the
required situation for the piglets including the required ambient temperature.
The second floor sections 11 are arranged so that a next adjacent
farrowing pen provides an adjacent floor seckion 1 1A with a further floor
section 10A
for the next adjaoent sow.
Each first floor section 10 includes a crate 12 providing confining walls
which locate the sow front and back and side to side so that the sow is
maintained in
the area on top of the floor and is prevented from moving to the sides into
the area
of the floor section 11 or out of the pen in front to rear direction. The
walls are
shown only schematically since these are well known to one skilled in the art
and the
construction can vary depending upon the particular manufacture of the
farrowing
crate. A feeder 13 is provided on a front wall 13A for providing feed and
water to the
sow when required. In order to take the feed and water, the sow stands on the
floor
section 10 to feed voluntarily and then to lie down when feeding is complete.
The floor sections 10 and 11 are arranged over a pit 14 having a pit
floor 15 onto which manure collects from the pens by passing through the
flooring
which is suitably perforated. The depth of the pit is generally of the order
of 18 to 24
inches which allows manure to collect in the bottom of the pit preferably up
to a
depth of no more than 9 to 15 inches for collection through a collection
system,
although in some rare cases of malfunction filling the pit,
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The floor section 10 is ca,rried on a pair of side rails 16 which provide a
top face 17 onto which the flooring rests so that it spans across the parallel
rails 10
and extends along the length of the rails and outwardiy beyond ends 18 of the
rails
to the front and rear of the pen. Different types of flooring rest upon the
rails 16 in a
5 different manner as required by the construction of the flooring and some
includes
fips which engage over the top face 17 and others sit within the top face 17.
The rails 16 are carried on a plate 20 which spans across the width of
the floor section 10 and extends along a part of the length of the rails 16.
The rails
are bolted to the plate 20 or may be welded to the plate along the side edges
of the
10 plate with the plate having sufficient length to provide support for the
rails 16 to
prevent bending, twisting or tilting.
The top plate 20 is supported on an inflatable gas bag 30. Such gas
bags are commercially available and are conventionally used in truck
suspension
systems but many different types of such bags having different inflation and
expansion parameters are available from commercial suppliers.
A commercially available valve 31 is provided which can be operated
to control air from an air supply 32 to a regulator vaive 34 through a line 33
and from
the valve 31 into the gas bag 30. The valve is normally maintained closed so
that
the bag is uninflated. The valve 31 includes an actuator which projects
upwardly as
a stud or button 35 extending through the siot between two of the rails 10B
(Figure
5) of the floor section 10. In some cases it is necessary to cut out a part or
one of
the rails or one of the parts of the flooring so as to allow the actuatQr pin
to project
through the floor into a position above the height of the flooring.
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The pin is covered by a channel member 37 which sits on top of the
pin and thus provides an elongate plate sitting on top of the floor section 10
slightly
raised from the floor. The plate has one end 38 (Figure 4) resting on the
floor and
the pin holds the other end upwardly from the floor so that the plate can be
pushed
down toward the floor by pressure from the sow. Thus the valve actuator pin 35
is
directly actuated by pressure from the sow and the channel provides an
increased
area over which the pressure from the sow can be applied causing the actuation
of
the valve. The channel 37 has depending side walls 39 which project between
the
rails I OB of the flooring to hold the plate in place. The plate may be
attached to the
top of the pin so that it cannot slide forwards and rearwards under forces
from the
sow.
The positioning of the plate is such that it is under the chest area of the
sow so as to provide effective contact when the sow lies down.
The valve 31 thus can be operated by release of pressure caused by
the animal tending to stand to allow the supply of air from the supply 32 into
the gas
bag 30 expanding the gas bag and causing the support for the floor to move
upwardly to the maximum height. This movement is effected relatively quickly
so
that the sow is lifted away from the side portions 11 of the flooring to the
raised
height while deterring any piglets from entering onto the center portion 10 of
the
flooring to be raised therewith.
As shown in Figure 2, on each side of the flooring portion 10 is
provided a panel 40 so as to close off the area on either side of the flooring
portion
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to prevent the piglets from entering into the area undemeath the flooring
portion
10.
When the sow lies down, this applies pressure onto the plate 37
actuating the valve so as to close off supply of air from a supply 32 and
acting to
5 release the air from the gas bag through a discharge orif+ce. The discharge
is
arranged so that the floor 10 moves relatively slowly in the downward
direction so
that the sow is given time to lie down before the floor reaches the lowered
position at
the height of the floor 11.
The device is thus arranged to save piglets from the first second of
10 birth to the day they get weaned. This unit works on air only. The unit is
arranged to
be installed beneath the sow's floor only, in existing barns or in new barn
construction. Every farrowing barn operation will benefit from this invention.
Even if the sow only sits up, the actuator valve on this unit wifl be
activated and it only takes approximately nine seconds for the sows to raise
up to
twelve inches. This does not give the piglets enough time to get beneath the
sow if
she decides to lay down again. Once the sow is standing the unit is fully
raised, her
piglets are now confined only on the second floor sections so she can eat and
drink
the sufficient amount she needs to conserve her body fat. If the sows eat well
this
means they will also milk well and that is what is required to wean big, nice
healthy
pigs. The time it takes for this unit to retract after the sow lays down again
is
approximately twenty seconds. This is sufficient time for most sows to have
laid on
their side again and by not having any piglets in her way so that the amount
of laid-
on and stepped-on pigs will be reduced tremendously.
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This unit will also give that extra time for the low viability piglets to gain
strength which normally they fall over beneath the sow while she is standing
and get
crushed by her because they are not strong enough to get out of her way. This
unit
is a low cost and low maintenance device for what it is capable of saving. Pre-
weaning mortality will decrease and pigs weaned per mated female per year will
increase. At weaning time the advantage of this unit is having a shut off
valve in the
farrowing room which means the sows will get out of the crates as normal. When
comes time to pick up the weanlings, one valve that supplies the air in that
room can
be operated and this means all the weanlings in each of these pens are
confined to
their storage space, this way it becomes one third of the area to catch them.
This
unit is effcient by itself and also efficient for the work load for hog
producers.
The structure which carries the air bag 30 is supported from the sides
of the pit rather than from the floor of the pit. This allows the floor of the
pit to be
open for the use of a conventional scraper which moves along the pit for
assisting in
manure removal. The support is of a low profile construction which allows the
bottom of the bag and the bottom of the guide mechanism to be raised as high
as
possible from the floor of the pit thus keeping the available depth of the pit
for
manure to a maximum.
Thus the system comprises a cradle 50 which is defined by a pair of
parallel rails 51 connected by a series of cross members 51A is mounted on the
end
plates 49 attached to the floor at the sides 52 of the pit 15 so that the
rails of the
cradle spans the width of the pit. The cradle provides a support for the first
floor
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section 10 on which the sow is supported. The first floor section 10 is
carried on the
rectangular support plate 20.
At the center section of the cradle 50 carried on the rails 51 is provided
a dropped support table 56 which is carried at a height below the rails 51 and
thus
below the top of the pit and below the floor. The table 56 carries the bottom
end 57
of the gas bag 30. The upper end 59 of the gas bag co-operates with a
receptacle
60 at the center of the rectangular support plate 20 for the first floor
section 10. The
gas bag thus provides motive force for raising and lowering the rectangular
floor
support section 10.
The floor support section 10 is guided so that it is maintained
horizontal by a scissors lift mechanism generally indicated at 61 which
comprises
diagonal link arms 62 and 63 which pivot at one end and slide at the other end
so as
to maintain the movement of the floor support section in a vertical direction
and
parallel to the cradle 50.
In an attemative shown in Figure 6, the vertical movement of the plate
and therefore the floor 10 is controlled and guided by rollers 64 which roll
in
vertical guide tracks 65. The rollers are carried on the cradle 50 and co-
operate with
the guide tracks 65 in the form of posts which extend downwardly from the
underside of the floor support plate 20.
20 The mechanism shown in this embodiment can be modified but the
principle involved is that the structure is supported as a cradle from the
side walls of
the pit and is formed as a low profile construction so that it is as close as
possible to
the underside of the floor maximizing the area in the pit for manure.
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is
In Figure 7 is shown a yet further arrangement which is mounted
wholly above the pit. In this arrangement there are provided four posts 80,
81, 82
and 83 which are arranged at the four comers of the first floor section
supporting the
sow. Side walts 84 of the farrowing crate contain the sow on the floor
section. At
the top of each post is provided a pulley 85 with a cable 86 which extends
downwardly from the pulley to the respective corner of the rectangular frame
providing support for the floor section. The cables 86 are pulled by an
actuating
system generally indicated at 87 which includes a central single gas bag 88
actuating a lever 89 to the drive a cable pulling system providing equal pull
on each
of the cables thus tending to lift the rectangular frame 55 in a vertical
direction. Side
to side and end to end swinging movement of the rectangular frame is prevented
by
slide guides 89 provided on the post which co-operate with projecting elements
90
provided on the frame 55 or on the confining rolls 84. The guide arrangements
can
of course vary and can include rollers or wheels which run in a suitable track
and the
selection of which element carries the track is of course of a minor nature.
The lifting system using the air bag is advantageous as previously
described in view of the simple nature of the actuating system which allows
the
pressure switch to be operated directly by the pressure from the body of the
sow.
In all cases the frame carries the depending side walls 40 which
prevent access to the pit from the piglets so that they are protected by the
side walls
40 which thus form a vertical protection wall as the frame carrying the sow
and the
confining walls is lifted.
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Since various modifications can be made in my invention as herein
above described, and many apparently widely different embodiments of same made
within the claims without departing from the invention, it is intended that
all matter
contained in the accompanying specification shall be interpreted as
iliustrat7ve only
and not in a limiting sense.