Technical Field
[0001] The present invention relates, in general, to tractors with rotatable articulated
arms and, more particularly, to a tractor with a rotatable articulated arm in which
a rotating shaft is installed around a driver cab of the tractor, and the articulated
arm is coupled to the rotating shaft so that the articulated arm can rotate around
the rotating shaft within as large an angular range as possible, whereby an operating
radius and working efficiency of an operating implement mounted to an end of the articulated
arm can be markedly improved.
Background Art
[0002] Generally, a tractor is an engineering vehicle designed to deliver a high tractive
force and conduct different kinds of work in the agriculture or construction field.
At present, tractors for agriculture typically include a front loader provided on
a front end of a tractor body, and an attachment mounted to the front loader so as
to conduct various kinds of work, such as transportation, unloading, loading, etc.
[0003] Recently, a technique in which a backhoe having an articulated arm is installed on
a front or rear end of a tractor to perform various kinds of work was proposed.
[0004] However, as described above, in the case where the loader is installed on the front
end of the tractor or the backhoe is provided on the rear end thereof, a workable
area of the tractor is limited to an area either in front of or to the rear of the
tractor. Therefore, if it is required to perform work in an area located to either
side of the driver cab, the tractor must be rotated in a direction corresponding to
the target area. This makes the work complicated and increases the time required to
conduct the work.
Disclosure
Technical Problem
[0005] Accordingly, the present invention has been made keeping in mind the above problems
occurring in the prior art, and an object of the present invention is to provide a
tractor with a rotatable articulated arm in which a rotating shaft is installed around
a driver cab of the tractor, and the articulated arm is coupled to the rotating shaft
so that the articulated arm can rotate around the rotating shaft within as large an
angular range as possible, whereby an operating radius and working efficiency of an
operating implement mounted to an end of the articulated arm can be markedly improved.
Technical Solution
[0006] In order to accomplish the above object, in an aspect, the present invention provides
a tractor with a rotatable articulated arm, wherein a driver cab is provided with
a driver seat and disposed on a body frame at a position displaced to one side from
a central portion of the body frame, a rotating shaft is installed around the driver
cab, and the articulated arm is installed on the rotating shaft so that the articulated
arm can rotate around the rotating shaft.
[0007] The articulated arm may include: a rotating boom coupled to the rotating shaft; a
first arm hinged to the rotating boom and vertically bent by a first hydraulic cylinder;
a second arm hinged to the first arm and vertically bent by a second hydraulic cylinder,
with an attachment provided on an end of the second arm.
[0008] In another aspect, the present invention provides a tractor with a rotatable articulated
arm, wherein a rotating shaft is installed around a driver cab, and the articulated
arm is coupled to the rotating shaft so that the articulated arm can rotate around
the rotating shaft, the articulated arm including: a rotating boom coupled to the
rotating shaft; a first arm hinged to the rotating boom and vertically bent by a first
hydraulic cylinder; a second arm hinged to the first arm and vertically bent by a
second hydraulic cylinder, wherein the first arm and the second arm are folded, the
first arm and the second arm form a Z shape along with the rotating boom.
[0009] Furthermore, a bucket may be mounted to the end of the second arm.
[0010] The rotating boom may be curved in an arc shape.
[0011] When the first arm and the second arm are completely folded, the first arm and the
second arm may be in space defined between four wheels of the tractor.
[0012] The first arm and the second arm may be configured such that when the first arm and
the second arm are folded, the first and second hydraulic cylinders are respectively
inserted into the first arm and the second arm.
[0013] The rotating shaft may be provided with a sprocket, and a chain may be coupled to
the sprocket, the chain being connected to first ends of operating rods of a pair
of third hydraulic cylinders, so that the rotating shaft is rotated by extension and
contraction of the third hydraulic cylinders.
[0014] The sprocket and the chain coupled to the sprocket may form at least a double sprocket-chain
structure.
[0015] Each of the third hydraulic cylinder may include a damping bushing provided on a
second end of the operating rod, and a damping chamber formed in an end of the third
hydraulic cylinder, the damping chamber forming a space into which the damping bushing
is inserted, wherein the space has a size at which a fine gap is formed when the damping
bushing is inserted into the damping chamber.
[0016] The rotating shaft may be disposed adjacent to a rear end of a side surface of the
driver cab, so that the rotating boom can rotate around the rotating shaft within
an angular range of 270°.
[0017] The rotating shaft may be fastened to the body frame or a rear axle.
Advantageous Effects
[0018] In a tractor with a rotatable articulated arm according to the present invention,
a rotating shaft is installed around a driver cab of the tractor, and the articulated
arm is coupled to the rotating shaft so that the articulated arm can rotate around
the rotating shaft within as large an angular range as possible (within an angular
range of about 270° in the case where the driver cab is disposed on a rear end of
a side portion of the tractor body). Thereby, an operating radius and working efficiency
of an operating implement mounted to an end of the articulated arm can be markedly
improved.
[0019] Furthermore, in the present invention, the rotating shaft is disposed around a rear
end of a side surface of the driver cab. Therefore, the articulated arm installation
structure of the present invention can reduce the whole length of the tractor.
[0020] Moreover, the articulated arm according to the present invention includes an arc-shaped
curved rotating boom and two arms (a first arm and a second arm), thus making it possible
for the tractor to conduct work even in a small place. Hence, the tractor of the present
invention can be used in a variety of work environments.
Description of Drawings
[0021]
Fig. 1 is a perspective view illustrating a tractor with a rotatable articulated arm,
according to the present invention;
Fig. 2 is a bottom view illustrating the tractor with the rotatable articulated arm
according to the present invention;
Fig. 3 is a view showing in detail the construction of a rotating shaft according
to the present invention;
Fig. 4 is a side view of the tractor when the articulated arm is oriented forwards
according to the present invention;
Fig. 5 is a side view of the tractor when the articulated arm is oriented rearwards
according to the present invention;
Fig. 6 is a side view of the tractor to illustrate an operating radius of the articulated
arm when it is oriented rearwards according to the present invention; and
Fig. 7 is a side view of the tractor to illustrate that it is possible for the tractor
to carry out work even when it is in a small space after the articulated arm has been
oriented rearwards.
<Description of the Reference Numerals in the Drawings>
[0022]
10: driver cab 21: front wheel
22: rear wheel 30: articulated arm
31: rotating boom 32: first arm
33: second arm 32a, 33a: hydraulic cylinder
40: rotating shaft 41: sprocket
42: chain 50: hydraulic cylinder
51: operating rod 52: damping bushing
53: damping chamber 54: fluid passage
60: frame box 61: bearing box
62, 63: bearing 70: hydraulic cylinder
80: bucket
Best Mode
[0023] Hereinafter, a tractor with a rotatable articulated arm according to the present
invention will be described in detail with reference to the attached drawings.
[0024] As shown in Figs. 1 and 2, in the tractor with the rotatable articulated arm according
to the present invention, a driver cab 10 having a driver seat therein is located
on a left side portion of a body of the tractor, and the rotatable articulated arm
30 is disposed on a portion of the tractor body where the driver cab 10 is not located,
so as to keep the balance of the tractor body.
[0025] In detail, the driver cab 10 is disposed between front wheels 21 and rear wheels
22 of the tractor and located on the left side portion of the tractor body such that
space is formed beside the driver cab 10. When the articulated arm 30 is not in use,
the articulated arm 30 is maintained in a folded state in this space.
[0026] A rotating shaft 40 is rotatably provided beside a rear end of a side surface of
the driver cab 10, in other words, at a position adjacent to one corner of the driver
cab 10. The articulated arm 30 is provided on the rotating shaft 40 so that the articulated
arm 30 can be rotated around the rotating shaft 40 by rotation of the rotating shaft
40. The location of the rotating shaft 40 is not limited to the vicinity of the rear
end of the side surface of the driver cab 10, and it can be disposed at any position,
so long as it is adjacent to the driver cab 10. The articulated arm 30 includes a
rotating boom 31 which is coupled to the rotating shaft 40, a first arm 32 which is
hinged to the rotating boom 31 and is vertically folded or unfolded by a hydraulic
cylinder 32a, and a second arm 33 which is hinged to the first arm 32 and is vertically
folded or unfolded by a hydraulic cylinder 33a. An attachment is provided on an end
of the second arm 33.
[0027] The first arm 32 and the second arm 33 respectively have spaces therein so that,
when the first arm 32 and the second arm 33 are folded, the hydraulic cylinder 32a
and the hydraulic cylinder 33a which operate the first and second arms 32 and 33 are
respectively inserted into the spaces of the first and second arms 32 and 33. Thanks
to this structure, interference with the hydraulic cylinder 32a or 33a can be minimized,
whereby the first arm 32 and the second arm 33 can be folded to the greatest extent.
[0028] As shown in Fig. 4, when the first arm 32 and the second arm 33 are folded, they,
along with the rotating boom 31, form a Z shape. Because the articulated arm 30 which
includes the rotating boom 31, the first arm 32 and the second arm 33 has the Z-shaped
structure, when the articulated arm 30 is not in operation, it can be stably maintained
in the folded state in the space formed beside the driver cab 10. Therefore, when
the tractor moves, it can move smoothly and without instability.
[0029] Furthermore, the tractor is configured such that, when the first arm 32 and the second
arm 33 are folded to the greatest extent, the first and second arms 32 and 33 are
in space defined between the front and rear wheels of the tractor. Thereby, when the
tractor travels, the first and second arms 32 and 33 can be maintained in a more stable
state.
[0030] The rotating boom 31 which is coupled to the rotating shaft 40 is configured to be
curved in an arc shape. Hence, after the articulated arm has been rotated rearwards,
that is, towards the rear wheels 22, by rotation of the rotating shaft 40, it becomes
possible to conduct work using the articulated arm, even in a small space, without
interference with the rear wheels 22.
[0031] Furthermore, when the articulated arm 30 is being rotated by the rotation of the
rotating shaft 40, except for the driver cab 10 which is disposed on the left portion
of the tractor body, nothing impedes the rotation of the articulated arm 30. Therefore,
the articulated arm 30 can easily rotate around the rotating shaft 40 within an angular
range other than an angular range within which it would interfere with the driver
cab 10. In the case where the driver cab 10 is disposed in a rear end of the left
side portion of the tractor, if the angular range within which the driver cab 10 impedes
the rotation of the articulated arm 30 is excluded, the articulated arm 30 can rotate
within an angular range of about 270° (from a range of about 260° to a range of about
290°).
[0032] Below, the structure for rotating the rotating shaft 40 will be described with reference
to Figs. 2 and 3.
[0033] As shown in Figs. 2 and 3, although it is preferable that the rotating shaft 40 is
installed in a frame box 60 provided in a rear end of a body frame, it may be installed
on a rear axle. A plurality of bearings 62 and 63 are provided around the rotating
shaft 40 so that it can smoothly rotate. A bearing box 61 which houses the bearing
62 therein is installed in the frame box 60.
[0034] Furthermore, a sprocket 41 is provided around a circumferential outer surface of
the rotating shaft 40. A chain 42 is wrapped around the sprocket 41. Opposite ends
of the chain 42 are respectively coupled to outer ends of operating rods 51 of two
hydraulic cylinders 50. Thus, the rotating shaft 40 can be rotated by extension and
contraction of the hydraulic cylinders 50.
[0035] In Fig. 3, a triple sprocket-chain structure having three sprockets 41 and three
chains 42 is illustrated as being used to increase rotating force of the articulated
arm 30 coupled to the rotating shaft 40. Preferably, a double sprocket-chain structure
comprising at least two sprockets and two chains is used.
[0036] Each hydraulic cylinder 50 includes a damping structure to prevent the rotating shaft
40 from excessively rapidly rotating.
[0037] The damping structure of the hydraulic cylinder 50 includes a damping bushing 52
which is provided on an inner end of the operating rod 51, and a damping chamber 53
which is formed in an end of the hydraulic cylinder and forms a space into which the
damping bushing 52 is inserted. The damping structure is configured such that, when
the operating rod 51 is completely extended and the damping bushing 52 is thus inserted
into the damping chamber 53, a narrow gap is formed and operating oil of the hydraulic
cylinder 50 comes out towards a fluid passage 54 through the narrow gap. At this time,
the expansion or contraction speed of the hydraulic cylinder 50 is reduced. In this
way, the damping function can be conducted.
[0038] Hereinafter, a working process of the tractor with the rotatable articulated arm
according to the present invention will be explained with reference to Figs. 4 through
7.
[0039] The attachment is provided on the end of the articulated arm 30 so that an operating
implement such as a bucket, a bale clamp, a fork lift, a hook, etc. can be easily
and removably mounted to the articulated arm 30. In an embodiment of Figs. 4 through
7, a small bucket 80 is provided on the end of the articulated arm 30.
[0040] When the tractor moves forwards or rearwards, the articulated arm 30 assumes the
position of Fig. 4. To conduct work in front of the tractor using the operating implement
(for example, a bucket) provided on the end of the articulated arm 30, from the state
of Fig. 4, the bucket 80 is moved forwards by folding or unfolding the first and second
arms 32 and 33 of the articulated arm 30, and the orientation of the bucket 80 is
adjusted by controlling the hydraulic cylinder 70 provided in the second arm 33.
[0041] When it is required to conduct work in an area to the side of the tractor that corresponds
to the right side of the driver cab 10, the rotating shaft 40 is rotated such that
the articulated arm 30 is oriented in the lateral direction of the tractor.
[0042] Furthermore, to conduct work backing an area to the rear of the tractor, as shown
in Fig. 5, the rotating shaft 40 is rotated such that the articulated arm 30 is oriented
rearwards. Here, the driver seat (not shown) provided in the driver cab 10 has a rotatable
structure. Therefore, after the driver seat has been rotated rearwards, the driver
in the seat can easily operate the articulated arm 30 without turning his/her head.
[0043] Meanwhile, because the articulated arm 30 includes the rotating boom 31 coupled to
the rotating shaft 40, and the first and second arms 32 and 33 which are hinged to
the rotating boom 31 and are respectively operated by the hydraulic cylinders 32a
and 33a, the operating radius of the articulated arm 30 can be increased, as shown
in Fig. 6, showing the case where the first arm 32 and the second arm 33 are extended.
[0044] Furthermore, since the rotating boom 31 of the articulated arm 30 has the arc-shaped
curved structure, as shown in Fig. 7, it can conduct work even in a small space without
being impeded by the rear wheels 22.
[0045] In the present invention having the above-mentioned construction, the articulated
arm 30 can rotate within an angular range of about 270°. The operating radius of the
operating implement mounted to the end of the articulated arm 30 can be further increased.
Thereby, operation efficiency of the tractor can be markedly enhanced.
[0046] Although the preferred embodiment of the present invention has been disclosed for
illustrative purposes, those skilled in the art will appreciate that various modifications,
additions and substitutions are possible, without departing from the scope and spirit
of the invention as disclosed in the accompanying claims.
1. A tractor with a rotatable articulated arm,
wherein a driver cab is provided with a driver seat and disposed on a body frame at
a position displaced to one side from a central portion of the body frame, a rotating
shaft is installed around the driver cab, and the articulated arm is installed on
the rotating shaft so that the articulated arm can rotate around the rotating shaft.
2. The tractor with the rotatable articulated arm of claim 1, wherein the articulated
arm comprises: a rotating boom coupled to the rotating shaft; a first arm hinged to
the rotating boom and vertically bent by a first hydraulic cylinder; a second arm
hinged to the first arm and vertically bent by a second hydraulic cylinder, with an
attachment provided on an end of the second arm.
3. A tractor with a rotatable articulated arm,
wherein a rotating shaft is installed around a driver cab, and the articulated arm
is coupled to the rotating shaft so that the articulated arm can rotate around the
rotating shaft, the articulated arm comprising: a rotating boom coupled to the rotating
shaft; a first arm hinged to the rotating boom and vertically bent by a first hydraulic
cylinder; a second arm hinged to the first arm and vertically bent by a second hydraulic
cylinder, wherein the first arm and the second arm are folded, the first arm and the
second arm form a Z shape along with the rotating boom.
4. The tractor with the rotatable articulated arm of claim 2 or 3, wherein a bucket is
mounted to the end of the second arm.
5. The tractor with the rotatable articulated arm of claim 2 or 3, wherein the rotating
boom is curved in an arc shape.
6. The tractor with the rotatable articulated arm of claim 2 or 3, wherein when the first
arm and the second arm are completely folded, the first arm and the second arm are
in space defined between four wheels of the tractor.
7. The tractor with the rotatable articulated arm of claim 2 or 3, wherein the first
arm and the second arm are configured such that when the first arm and the second
arm are folded, the first and second hydraulic cylinders are respectively inserted
into the first arm and the second arm.
8. The tractor with the rotatable articulated arm of claim 2 or 3, wherein the rotating
shaft is provided with a sprocket, and a chain is coupled to the sprocket, the chain
being connected to first ends of operating rods of a pair of third hydraulic cylinders,
so that the rotating shaft is rotated by extension and contraction of the third hydraulic
cylinders.
9. The tractor with the rotatable articulated arm of claim 8, wherein the sprocket and
the chain coupled to the sprocket form at least a double sprocket-chain structure.
10. The tractor with the rotatable articulated arm of claim 8, wherein each of the third
hydraulic cylinder includes a damping bushing provided on a second end of the operating
rod, and a damping chamber formed in an end of the third hydraulic cylinder, the damping
chamber forming a space into which the damping bushing is inserted, wherein the space
has a size at which a fine gap is formed when the damping bushing is inserted into
the damping chamber.
11. The tractor with the rotatable articulated arm of claim 2 or 3, wherein the rotating
shaft is disposed adjacent to a rear end of a side surface of the driver cab, so that
the rotating boom can rotate around the rotating shaft within an angular range of
270°.
12. The tractor with the rotatable articulated arm of claim 2 or 3, wherein the rotating
shaft is fastened to the body frame or a rear axle.