CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is based on and claims priority from Korean Patent Application No.
10-2008-0020030, filed on March 4, 2008 in the Korean Intellectual Property Office, the disclosure of which is incorporated
herein in its entirety by reference.
BACKGROUND OF THE INVENTION
Field of the invention
[0002] The present invention relates to an apparatus for fixing hydraulic pipes for construction
equipment, which can facilitate joint connection of return pipes for returning hydraulic
fluid of a main control valve (MCV), which controls the flow of hydraulic fluid being
supplied to a working device and so on, to a hydraulic tank even in a narrow working
space of an upper frame.
[0003] More particularly, the present invention relates to an apparatus for fixing hydraulic
pipes for construction equipment, which can facilitate joint connection of return
pipes having a large size to a hydraulic tank, in an environment where a working space
of an upper frame is narrow such as in a small swing radius construction equipment,
by a return pipe block for returning hydraulic fluid of a main control valve to the
hydraulic tank without being interfered with a swing motor and so on.
Description of the Prior Art
[0004] Generally, a swing excavator is classified into a standard swing excavator and a
small swing radius excavator.
[0005] In the standard swing excavator, if an upper frame has a posture directed to a forward/backward
direction against a lower driving structure (i.e. if a working device has a posture
directed to the traveling direction of the lower driving structure), a rear end part
of the upper frame projects to an outside so as to be longer than a front/rear part
of the lower driving structure (i.e. an end part in a traveling direction). If the
upper frame has a posture directed to a horizontal direction against the lower driving
structure (i.e. if the working device has a posture directed to a direction perpendicular
to the traveling direction of the lower driving structure), the rear end part of the
upper frame projects to an outside so as to be longer than a left/right part of the
lower driving structure (i.e. an end part in a direction perpendicular to the traveling
direction).
[0006] Accordingly, since a distance from the rear end part of the upper frame to the swing
center thereof is long and the rotational moment of the rear part of the upper frame
becomes high, it is difficult that the rotational moment of the front part of the
upper frame that is generated by the excavation force of the working device causes
the overturning of the excavator. Accordingly, the excavator can provide a large excavation
force, and thus the workability is improved.
[0007] As illustrated in FIG. 1, a conventional apparatus for fixing hydraulic pipes for
construction equipment includes a return pipe 3 for returning hydraulic fluid from
a main control valve 1 that controls a flow of the hydraulic fluid being supplied
to a working device and so on to a hydraulic tank 2 via an oil cooler (not illustrated),
or returning the hydraulic fluid from the main control valve 1 to the hydraulic tank
2 without passing through the oil cooler if back pressure over a specified pressure
is formed in a feedback line of the hydraulic tank 2.
[0008] In this case, the return pipe 3 is joint-connected to keep away from a swing motor
4 due to a narrow working space of an upper frame.
[0009] As illustrated in FIG. 2, according to the conventional apparatus for fixing hydraulic
pipes for construction equipment (e.g. small swing radius equipment), the return pipe
3 is installed to keep away from the swing motor 4 since the working space of the
upper frame 6 is not sufficient due to the characteristic of the small swing radius
equipment. Accordingly, the return pipe 3 is connected by using a one-piece hose,
or is joint-connected to a side surface of the hydraulic tank 2 by utilizing a front
space of the hydraulic tank 2.
[0010] In this case, since the return pipe 3 connected to the oil cooler 5 is arranged to
be in close contact with an outer surface of the swing motor 4, the return pipe 3
is joint-connected after the swing motor 4 is first mounted on the upper frame 6.
Accordingly, when the return pipe 3 is joint-connected, it is interfered with hydraulic
pipes joint-connected to the swing motor 4 to lower the working efficiency.
[0011] On the other hand, as the utility of the small swing radius equipment is increased,
the frequency in replacement of option devices, such as hammer, shear, quick fit,
and the like, is also increased. Also, as the size of the return pipe 3 is increased,
the working space of the upper frame 6 becomes narrower to lower the space utility.
Accordingly, the return pipe 3 is installed to be arranged in front of the swing motor
4.
[0012] That is, due to the insufficient working space between the swing motor 4 and the
fixing part of the working device, the work time for joint-connecting the return pipe
3 is increased to lower the working efficiency, and the safety of the worker who works
in a narrow working space is lowered.
SUMMARY OF THE INVENTION
[0013] Accordingly, the present invention has been made to solve the above-mentioned problems
occurring in the prior art, and an object of the present invention is to provide an
apparatus for fixing hydraulic pipes for construction equipment, which can facilitate
joint connection of return pipes having a large size to a hydraulic tank, in an environment
where a working space of an upper frame is narrow, by a return pipe block for returning
hydraulic fluid of a main control valve to the hydraulic tank without being interfered
with a swing motor and so on, so that the working time can be shortened and the working
space can be secured.
[0014] In order to accomplish the above and other objects, there is provided an apparatus
for fixing hydraulic pipes for construction equipment having return pipes for returning
hydraulic fluid from a main control valve to a hydraulic tank or an oil cooler, according
to an embodiment of the present invention, which includes a first return joint pipe
having an inlet port joint-connected to the main control valve; a second return joint
pipe having an outlet port joint-connected to the oil cooler; a return pipe block
mounted on an upper frame between a frame to which a working device is fixed and a
swing motor, and joint-connected to an outlet port of the first return joint pipe
and an inlet port of the second return joint pipe, respectively; and a third return
joint pipe having an inlet port joint-connected to the return pipe block and an outlet
port joint-connected to the hydraulic tank; wherein the return pipe block is mounted
on the upper frame to joint-connect the first and second return joint pipes, and the
third return joint pipe is joint-connected to the return pipe block and the hydraulic
tank, respectively, after the swing motor is mounted on the upper frame.
[0015] The return pipe block may be mounted on the upper frame in front of the swing motor.
[0016] A hydraulic hose or pipe may be used as the third return joint pipe.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The above and other objects, features and advantages of the present invention will
be more apparent from the following detailed description taken in conjunction with
the accompanying drawings, in which:
FIG. 1 is a schematic view illustrating a conventional apparatus for fixing hydraulic
pipes for construction equipment;
FIG. 2 is a view illustrating a modified example of a conventional apparatus for fixing
hydraulic pipes for construction equipment;
FIG. 3 is a schematic view illustrating an apparatus for fixing hydraulic pipes for
construction equipment before a swing motor is mounted on an upper frame according
to an embodiment of the present invention;
FIG. 4 is a view illustrating the used state of an apparatus for fixing hydraulic
pipes for construction equipment according to an embodiment of the present invention;
and
FIG. 5 is a plan view of an apparatus for fixing hydraulic pipes for construction
equipment according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] Hereinafter, preferred embodiments of the present invention will be described with
reference to the accompanying drawings. The matters defined in the description, such
as the detailed construction and elements, are nothing but specific details provided
to assist those of ordinary skill in the art in a comprehensive understanding of the
invention, and thus the present invention is not limited thereto.
[0019] As shown in FIGS. 3 to 5, an apparatus for fixing hydraulic pipes for construction
equipment having return pipes for returning hydraulic fluid from a main control valve,
which controls the flow of hydraulic fluid being supplied to a working device and
so on, to a hydraulic tank or an oil cooler, according to an embodiment of the present
invention, includes a first return joint pipe 10 having an inlet port joint-connected
to the main control valve 1; a second return joint pipe 11 having an outlet port joint-connected
to the oil cooler 5; a return pipe block 13 mounted on an upper frame 6 between a
frame 12, to which a working device such as a boom and so on is fixed, and a swing
motor 4, and joint-connected to an outlet port of the first return joint pipe 10 and
an inlet port of the second return joint pipe 11, respectively; and a third return
joint pipe 14 having an inlet port joint-connected to the return pipe block 13 and
an outlet port joint-connected to the hydraulic tank 2; wherein the return pipe block
13 is mounted on the upper frame 6 to joint-connect the first and second return joint
pipes 10 and 11, and the third return joint pipe 14 is joint-connected to the return
pipe block 13 and the hydraulic tank 2, respectively, after the swing motor 4 is mounted
on the upper frame 6.
[0020] The return pipe block 13 is mounted on the upper frame 6 in front of the swing motor
4 so that the return pipe block 13 can be installed in an optimum position with respect
to the main control valve 1, the swing motor 4, the hydraulic pump, and the like.
[0021] A hydraulic hose or pipe is used as the third return joint pipe 14 in accordance
with the working capacity, model number, and the like, of the construction equipment.
[0022] Hereinafter, the operation of the apparatus for fixing hydraulic pipes for construction
equipment according to an embodiment of the present invention will be described in
detail with reference to the accompanying drawings.
[0023] As illustrated in FIG. 5, the return pipe block 13 is mounted on the upper frame
6 between the frame 12, to which a working device such as a boom and so on is rotatably
fixed, and the swing motor 4. The first return joint pipe 10 and corresponding pipes
for constructing a hydraulic circuit are joint-connected to the main control valve
1 and the return pipe block 13, respectively, in accordance with the designed hydraulic
circuit.
[0024] The second return joint pipe 11 and corresponding components for constructing the
hydraulic circuit are joint-connected to the return pipe block 13 and the oil cooler
5, respectively, in accordance with the designed hydraulic circuit.
[0025] In this case, the construction in which the first return joint pipe 10 is joint-connected
to the main control valve 1 and the return pipe block 13 and the construction in which
the second return joint pipe 11 is joint-connected to the return pipe block 13 and
the oil cooler 5 are well known and used in the corresponding technical field, and
thus the detailed description thereof will be omitted.
[0026] After the swing motor 4 is mounted on the upper frame 6, the third return joint pipe
14 is joint-connected to the return pipe block 13 and the hydraulic tank 2, respectively,
in accordance with the designed hydraulic circuit.
[0027] In this case, the construction in which the third return joint pipe 14 is joint-connected
to the return pipe block 13 and the hydraulic tank 2, respectively, is well known
and used in the corresponding technical field, and thus the detailed description thereof
will be omitted.
[0028] On the other hand, the hydraulic fluid from the main control valve 1, which controls
the flow of the hydraulic fluid being supplied to the working device, is returned
to the hydraulic tank 2 after passing through a return line composed of the first
return joint pipe 10, the return pipe block 13, the second return joint pipe 11, the
oil cooler 5, and a drain pipe path 15.
[0029] If back pressure over a specified pressure is formed in a feedback line of the hydraulic
tank 2, the hydraulic fluid from the main control valve 1 is returned to the hydraulic
tank 2 through a return line composed of the first return joint pipe 10, the return
pipe block 13, and the third return joint pipe 14.
[0030] As described above, according to the present invention, the fixing of the hydraulic
pipes is performed through two work processes in order: a first work process of joint-connecting
the first and second return joint pipes 10 and 11 to the main control valve 1 and
the oil cooler 5, respectively, by using the return pipe block 13 mounted on the upper
frame before the swing motor 4 is mounted on the upper frame 6; and a second work
process of joint-connecting the third return joint pipe 14 to the return pipe block
13 and the hydraulic tank 2, respectively, after the swing motor 4 is mounted on the
upper frame 6.
[0031] Accordingly, even in the case of joint-connecting the return pipes to the hydraulic
tank in the small swing radius equipment, the working space can be secured, and thus
the return pipes having a large size can be easily joint-connected.
[0032] As described above, the apparatus for fixing hydraulic pipes for construction equipment
according to the embodiment of the present invention has the following advantages.
[0033] In the case of joint-connecting the return pipes having a large size to the hydraulic
tank in an environment where the working space of the upper frame is narrow, since
the work process of assembling the swing motor is simplified by the return pipe block
for returning the hydraulic fluid of the main control valve to the hydraulic tank,
the working time is shortened and the working space is secured to improve the working
efficiency.
[0034] Although preferred embodiments of the present invention have been described 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.