[0001] The invention relates to an apparatus for supporting a leg of an animal, in particular
a foreleg of a four-legged animal, in order to, for instance, inspect and/or treat
a claw or hoof of the animal.
[0002] Such an apparatus is known from practice and usually comprises a supporting element
on which the respective leg can be fixed in a suitable position, and a winch with
which the leg can be hoisted onto the supporting element. To this end, the winch is
provided with a spool and a cord that can be fastened by one end around the leg of
the animal and then, with the aid of a crank or like drive element, can be wound onto
the spool. Further, blocking means can be provided for blocking the unwinding of the
spool so that during winding, the cord cannot be unwound through resisting movements
of the animal. Also, releasing means can be provided, with which the blocking action
of the blocking means can be at least temporarily eliminated, in order to give the
user the opportunity to, for instance, unwind the cord to a sufficient extent for
it to be fastened around the leg, or in order to, afterwards, lower the leg from the
supporting element. In particular in the latter case, dangerous situations may arise
through unexpected jerking movements to the cord by the animal, so that the spool
and the drive element are suddenly accelerated and can inflict injuries or damage
to a person or object present in the path of movement of the drive element. Due thereto,
also, damage may be done to the apparatus itself, in particular to the drive element.
[0003] The invention contemplates providing an apparatus of the type described hereinabove,
wherein said drawback of the known apparatus is obviated, while maintaining the advantages
thereof. To that end, an apparatus according to the invention is characterized in
that immobilizing means are provided, allowing immobilization of the drive element
at least in an unwinding direction, for as long as the blocking action of the blocking
means is deactivated. In this manner, during unwinding, the drive element can maintain
a substantially fixed position, irrespective of any jerking forces applied on the
spool via the cord to be unwound. Thus, the safety of the apparatus is considerably
increased.
[0004] The immobilizing means can be continuously activated, for instance through the use
of a freewheel mechanism or ratchet mechanism connecting the drive element to the
spool in a manner secured against rotation in winding direction, but allowing free
rotation in unwinding direction. However, the immobilizing means can also be only
temporarily activated, in particular when the blocking means are deactivated.
[0005] This activating of the immobilizing means is preferably done "automatically", for
instance by designing the releasing means such that, when the blocking means are deactivated,
they instantaneously activate the immobilizing means. Alternatively, the releasing
means and optional operating means of the immobilizing means may be designed such
that the releasing means can be operated only after the immobilizing means have been
activated. Thus, the immobilizing means will always be activated at the right time,
and they cannot be inadvertently forgotten so that a particularly safe, foolproof
apparatus is obtained.
[0006] Immobilizing the drive element can be effected in different manners. For instance,
the drive element can be physically blocked or held, for instance by a blocking element
that can be temporarily provided in the path of movement of the drive element, thus
preventing rotation of the drive element in unwinding direction. If desired, a freewheel
mechanism can be provided between the spool and the drive element, in order not to
hinder the unwinding of the spool.
[0007] In an alternative embodiment, the drive element can be immobilized by uncoupling
this element from the spool, at least temporarily, so that a movement of the spool,
in particular a rotation in unwinding direction is not transmitted to the drive element.
To that end, the drive element can for instance be uncoupled from the spool, or a
connection secured against rotation between the two can be eliminated so that the
spool and the drive element can rotate freely relative to each other. Alternatively,
the drive element can be connected to the spool via a freewheel mechanism which, in
the winding direction, connects the drive element to the spool in a manner secured
against rotation and, in the unwinding direction, allows free rotation. As a result,
the drive element is permanently immobilized in unwinding direction, which leads to
a very safe apparatus.
[0008] The blocking means too can be designed in different manners. They can for instance
directly engage the elongated element, so as to prevent it from unwinding, or indirectly
engage the spool so as to prevent rotation in unwinding direction. In this latter
case, use may be made of a freewheel mechanism or ratchet mechanism allowing rotation
of the spool in winding direction but blocking it in unwinding direction. Such a ratchet
mechanism can have a relatively simple and robust construction and can absorb great
forces, whereby such a mechanism is highly suitable for use in an apparatus according
to the invention.
[0009] In a particularly advantageous embodiment, the blocking means and the drive element
can be connected to the spool via a common coupling part, while this coupling part
can be connected to the spool, at wish, in a manner secured against rotation or in
a rotatable manner, by means of the releasing means. As a result, the blocking means
and the drive element can simultaneously be uncoupled from the spool, with one single
operating movement of the releasing means, so that the blocking action of the blocking
means is eliminated and the drive element is immobilized. Such an embodiment can therefore
be operated in a simple and foolproof manner and can furthermore be constructed relatively
simply with a minimum of parts.
[0010] The coupling part may be designed as a ring which is arranged for free rotation around
an end of the spool, and the releasing means can for instance comprise a displaceable
coupling pin or key which, in a coupled position, can project through the coupling
part and the spool in order to connect the two parts in a manner secured against rotation
and which, for the purpose of a releasing position can be (manually) removed in order
to have the two parts rotate freely relative to each other.
[0011] In an advantageous embodiment, biasing means can be provided for biasing the releasing
means in one of the above-mentioned positions, preferably in the coupled position.
In this position, it is standard that the spool be secured against unwinding and ready
to be wound without further operations being required thereto, and thus, a very safe
and easy to operate apparatus is obtained.
[0012] Further, locking means can be provided, with which the releasing means can be fixed
in a releasing position, in which releasing position the drive element is immobilized
and the spool can be unwound. As a result, a user needs not hold the releasing means
in said releasing position by hand (against a biasing force) so that his hands remain
free for, for instance, treating and guiding the leg.
[0013] In the further subclaims, further advantageous embodiments are described of an apparatus
according to the invention, and an apparatus equipped therewith for treating a four-legged
animal.
[0014] In clarification, hereinafter, an exemplary embodiment of an apparatus according
to the invention and the use thereof will be further elucidated with reference to
the drawing. In the drawing:
Fig. 1 shows, in perspective side view, a leg rest according to the invention, with
a foreleg to be treated of an animal thereon;
Fig. 2 shows the leg rest according to Fig. 1, in side view;
Fig. 3 shows the leg rest according to Figs. 1 and 2, in bottom view, with a view
on the winch; and
Fig. 4 shows, in cross-section, the winch according to Fig. 3.
[0015] The leg rest 1 shown in Figs. 1 - 4 comprises a substantially block-shaped supporting
element 2 and a frame 3 with which the supporting element 2 can be connected to the
fixed world W, this in a manner such that a side facing upwards of the supporting
element 2 extends substantially horizontally and can thus serve as bearing face 4
for a leg P to be treated as shown in Fig. 1.
[0016] The supporting element 2 can for instance be designed as a block of wood, the side
of which that serves as bearing face 4 preferably having a slight concave shape so
that the leg P can be supported comfortably and the leg P can be better prevented
from sliding from the bearing face.
[0017] The fixed world W can for instance be a box stall or, as is the case in the exemplary
embodiment shown in Fig. 1, a cage-shaped construction in which the animal, during
treatment, can be temporarily accommodated in order to limit its freedom of movement.
If desired, such a construction can be designed to be wheeled. Herein, the term "fixed
world" W is therefore to be interpreted broadly.
[0018] The leg rest 1 further comprises a winch 5 for winding and unwinding an elongated
element such as a band or cord 6. In use, this cord 6 is fastened by one free end
around the leg P to be treated, whereupon the leg P is hoisted with the winch onto
the supporting element 2. If desired, the free cord end can be provided with suitable
fastening means such as a loop, belt or hook (not shown) so that fastening around
the leg P is simplified and/or the comfort for the animal is enhanced.
[0019] The winch 5 comprises a spool 8 (see Fig. 3) which is suspended for rotation in the
frame 3 between two side pieces 9. The above-mentioned cord 6 is fastened by a first
end to this spool 8 and run by the free end through the supporting element 2, via
an opening 1 provided thereto, all this being arranged such that, due to rotation
of the spool 8, this cord 6 is wound in a winding direction (counter-clockwise in
Fig. 2), and is unwound in an unwinding direction. For rotating the spool 8, a drive
element 12 is provided which, in the example shown, is designed as a manually operable
crank which is detachably coupled to an end of the spool 8 in a manner to be described
further. The spool 8 further comprises blocking means 10 which, in a blocking position,
allow rotation of the spool 8 in the winding direction but block in the unwinding
direction.
[0020] In the exemplary embodiment shown, the blocking means 10 comprise a ratchet mechanism,
provided with a toothed wheel 14, which, in a manner to be described further, is fastened
to the spool 8 and can, thus, rotate along with the spool 8, a pawl 15, connected
for rotation to the frame 3 and engaging, by a free end, the toothing of the wheel
14, and a stroke limiting device 13 in the form of a pin 13, arranged in the path
of rotation of the pawl 15 and, thus, limiting the angle of rotation of the pawl 15
so that it cannot be rotated beyond its range of operation by too abrupt an acceleration
of the wheel 14.
[0021] In the exemplary embodiment shown, the drive element (crank) 12 and the blocking
means (toothed wheel) 14 are fastened to the spool 8 so they can be uncoupled via
releasing means, in particular a coupling ring 18, which has been slid for rotation
around a free end 17 of the spool 8 and can be coupled to this spool end 17 in a manner
secured against rotation with the aid of a coupling pin 20, while the coupling pin
20 is run through opposing holes 21, 22, in the coupling ring 18 and the spool end
17, respectively.
[0022] In the exemplary embodiment shown, the coupling pin 20 is slideably connected to
the crank 12 and is preferably biased in the above-mentioned coupled position, via
biasing means 23, for instance a spiral spring as shown in Figs. 3 and 4. This coupled
position can be eliminated by manually pulling the coupling pin 20 back against the
biasing force to an uncoupled position in which the pin 20 has been pulled from the
holes 21, 22 in the direction of arrow A, in Fig. 4. If desired, a locking option
may be provided (not shown) for securing the coupling pin 20 in the uncoupled position
so that a user can keep his both hands free for guiding the leg P. In the uncoupled
position, the connection secured against rotation between the spool 8 and coupling
ring 18 will be eliminated. As a result, the spool 8 will be able to rotate freely
relative to the coupling ring 18 and the drive element 12 and ratchet mechanism 10
connected thereto, while the blocking action of this ratchet mechanism 10 in unwinding
direction will be eliminated.
[0023] The leg rest 1 can further comprise various fastening provisions, such as an opening
24 and/or a cleat (as shown in Fig. 2) for fastening further cords, tensioning means
or the like with which the leg P can be fixed on the supporting element 2 in a position
for treatment.
[0024] The above-described leg rest 1 can be used as follows. An animal to be treated is
positioned adjacent the leg rest 1, whereupon the cord 6 is unwound to such an extent
that it can be fastened around the leg P of the animal. To unwind the cord 6, the
blocking means (the ratchet mechanism 10) are to be eliminated with the aid of the
releasing means (coupling ring 10, coupling pin 20). To that end, the coupling pin
20 is pulled by hand in the direction of the arrow A, against the biasing force. As
a result, also, the drive element (crank 12) is uncoupled, which is fixedly connected
to the coupling ring 18. Hence, this crank 12 will not rotate along with the unwinding
the cord 6 and the associated rotation of the spool 8. After the cord 6 has been unwound
to a sufficient extent, the coupling pin 20 is let go of or unlocked, so that it is
brought by the biasing means 23 in the coupled position in which the coupling ring
18, the ratchet mechanism 10 and the crank 12 are connected to the spool 8 in a manner
secured against rotation. As a result, further unwinding of the cord 6 will be prevented
by the ratchet mechanism 10, and a user has his hands free for fastening the cord
6 around the leg P of the animal. Then, the cord 6 can be wound by operating the crank
12, the leg P being pulled along by the cord 6 in the direction of the supporting
element 2. The ratchet mechanism 10 prevents the cord 6 from being unwound due to
any resisting forces of the animal. Thus, the cord 6 can be wound up until the leg
P is located on the bearing face 4. Then, the leg P can be fixed in a desired position
with further cords, tensioning means or the like that can be secured in the fastening
means 24, 25. Thereupon, the leg P can be inspected and/or treated. Upon termination
of the treatment, the blocking action of the ratchet mechanism 10 is eliminated in
a manner described hereinabove, that is to say by pulling the coupling pin 20 by hand
from the coupled position against the biasing force. As a result, also, the crank
12 will be uncoupled so that it will not rotate along with the spool 8. Instead thereof,
the crank 12 is held in a position of rest by the pawl 15. In this manner, dangerous
situations can be avoided as sudden jerks to the cord by the animal, and associated
sudden rotation of the spool 8 cannot be transmitted to the crank 12.
[0025] The invention is not limited in any manner to the exemplary embodiments represented
in the description and the drawing. All combinations of (parts of) embodiments described
and/or shown are understood to fall within the inventive concept. Moreover, many variants
thereon are possible within the framework of the invention as outlined by the claims.
[0026] For instance, the drive element and the blocking means can be coupled to the spool
of the winch via separate coupling and/or releasing means, while the releasing means
for uncoupling (eliminating) the blocking means can be operated or become accessible
only after the drive element has been uncoupled. As a result of this too, the drive
element is prevented from not being connected to the spool when this spool can unwind.
Alternatively, the drive element can be fastened to the spool of the winch by means
of a second ratchet mechanism, whereby, in a winding direction, the drive element
is connected to the spool in a manner secured against rotation and can rotate freely
in opposite direction relative to the spool. Further, the blocking means for blocking
the unwinding of the cord can engage the cord itself instead of the spool. In this
case too, the releasing means for removing these blocking means are designed such
that engagement or operation thereof can be effected only after the drive element
has been uncoupled from the spool.
[0027] These and many variations are understood to fall within the framework of the invention
as set forth in the following claims.
1. An apparatus (1) for supporting a leg (P) of an animal, comprising a supporting element
(2) and a winch (5) for hoisting the respective leg (P) on the supporting element
(2), the winch comprising a rotatable spool (8) provided with a drive element (12)
for winding and unwinding an elongated element (6), blocking means for blocking the
unwinding of the elongated element (6) and releasing means for deactivating the blocking
means (10) at least releasing the unwinding of the elongated element (6), characterized in that further, immobilizing means are provided for immobilizing, at least in an unwinding
direction, the drive element (12) for as long as the blocking means (10) are deactivated.
2. An apparatus (1) according to claim 1, wherein the immobilizing means can be activated
and deactivated.
3. An apparatus (1) according to claim 1 or 2, wherein the releasing means are designed
such that through deactivation of the blocking means (10), the immobilizing means
are activated, so that the drive element (12) is immobilized.
4. An apparatus (1) according to any one of the preceding claims, wherein the immobilizing
means are designed for connecting the drive element (12) to the spool (8), at wish,
in a manner secured against rotation or in a freely rotatable manner.
5. An apparatus (1) according to any one of the preceding claims, wherein the immobilizing
means comprise a freewheel mechanism or ratchet mechanism which connects the drive
element (12) to the spool (8) in a manner secured against rotation in the winding
direction, and allows rotation in the unwinding direction.
6. An apparatus (1) according to any one of the preceding claims, wherein the blocking
means (10) comprise a ratchet mechanism, provided with a wheel (14) with a toothed
circumference and a pawl (15) which is arranged for movement into and out of the path
of movement of the toothed circumference.
7. An apparatus (1) according to claim 6, wherein, with the aid of the releasing means,
the wheel (14) can, at wish, be connected to the spool (8) in a manner secured against
rotation or in a freely rotatable manner.
8. An apparatus (1) according to any one of the preceding claims, wherein the blocking
means (10) and the immobilizing means are connected via a common coupling part (18)
to the spool (8), which coupling part (18) can be connected to the spool (8) by means
of the releasing means, at wish in a manner secured against rotation or in a freely
rotatable manner.
9. An apparatus (1) according to claim 8, wherein the coupling part comprises a coupling
ring (8) which is provided around an end of the spool (8).
10. An apparatus (1) according to claim 8 or 9, wherein the releasing means comprise a
coupling pin (20) which can be displaced between a coupled position in which the pin
(20) extends into the coupling part (18) and the spool (8), and a releasing position
in which the coupling part (18) can rotate freely relative to the spool (8).
11. An apparatus (1) according to any one of the preceding claims, wherein the releasing
means (20) are biased in a coupled position, in which position the blocking means
(10) are activated.
12. An apparatus (1) according to any one of the preceding claims, wherein locking means
are provided for fixing the releasing means (20) in a releasing position, in which
position the blocking means are deactivated.
13. An apparatus (1) according to any one of the preceding claims, wherein the elongated
element (6) is provided with fastening means for fastening around a leg (P) to be
supported.
14. An apparatus (1) for treatment of a four-legged animal, comprising a cage-shaped construction,
designed for limiting the freedom of movement of an animal accommodated within this
construction, wherein the apparatus comprises at least one supporting apparatus (1)
according to any one of the preceding claims.