JP2001055921A - Turning type construction machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a burden on an oil cooler to miniaturize the oil cooler by cooling hydraulic oil when the hydraulic oil flows through a return pipe. SOLUTION: In this construction machine, the downstream side of an oil cooler inflow side pipe 19 in a return pipe 18 for returning hydraulic oil from a multiple valve device to a hydraulic oil tank 13 is a rising pipe part 19C for heat radiation, while the rising pipe part 19C is disposed along the front face of a radiator 9 nearly perpendicularly to the flow direction of cooling air supplied from a cooling fan 7. Thereby, when the heated hydraulic oil is returned from the multiple valve device, the cooling air of the cooling fan 7 can cools the rising pipe part 19C for heat radiation. Accordingly, an oil cooler having small cooling capacity, i.e., a small-size oil cooler can be used to reduce a mounting space of the oil cooler.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a swing type construction machine suitably used as, for example, a hydraulic shovel, a hydraulic crane and the like.

[0002]

2. Description of the Related Art In general, a hydraulic shovel or the like is known as a swing type construction machine. The hydraulic excavator is composed of a lower traveling body and an upper revolving body pivotally mounted on the lower traveling body, and a work device for excavating earth and sand, etc., is raised and lowered on a front side of the upper revolving body. It is provided as possible.

[0003] A conventional hydraulic excavator of this type is known from Japanese Utility Model Laid-Open No. 6-28227. The upper revolving structure according to the prior art is mounted on a revolving frame and a cooling fan positioned on the left side of the revolving frame in a horizontal position extending left and right on the revolving frame. , A hydraulic pump mounted on the right side of the left and right directions of the engine, a radiator provided near the cooling fan for cooling engine cooling water and an oil cooler for cooling hydraulic oil, A multiple valve device disposed in front of the engine and connected to the hydraulic pump; a hydraulic oil tank disposed in front of the hydraulic pump for storing hydraulic oil to be supplied to the hydraulic pump; A return pipe for returning hydraulic oil to the hydraulic oil tank via a cooler.

The hydraulic excavator described in Japanese Utility Model Laid-Open Publication No. Hei 6-28227 connects a return pipe extending to an oil cooler to a lower part of the oil cooler through a vicinity of an engine, a cooling fan, and a side of a radiator. are doing.

[0005] In these conventional hydraulic excavators, when an engine is driven, a hydraulic pump is driven by the engine, and the hydraulic pump supplies pressure oil to a multiple valve device or the like. Thereby, for example, pressure oil is supplied to the actuator of the working device, and the working device is raised and lowered to perform excavation work of earth and sand.

The hydraulic oil is a hydraulic pump, a multiple valve device,
Since the temperature rises due to various actuators and the like, the hydraulic oil returned from the multiple valve device to the hydraulic oil tank is returned to the hydraulic oil tank via the oil cooler. This allows
The hot working oil is cooled by an oil cooler and returned from the oil cooler to a working oil tank.

[0007]

The hydraulic excavator according to the prior art described above supplies working oil heated by an actuator or the like to an oil cooler via a return pipe, and operates after being cooled by the oil cooler. It is returning to the oil tank.

However, since the oil cooler is disposed near the engine together with the radiator, the return pipe connected to the oil cooler also passes near the engine. For this reason, the hydraulic oil flowing through the return pipe is heated by the heat of the engine. Therefore, in order to cool the hydraulic oil to an appropriate temperature, it is necessary to increase the capacity of the oil cooler. In addition, when the oil cooler is enlarged, a large space for installing the oil cooler is required, and more hydraulic oil is required for the enlarged oil cooler. There is a problem that the size is increased.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art. It is an object of the present invention to cool an operating oil while the operating oil is flowing through a return pipe, thereby reducing the burden on an oil cooler. It is an object of the present invention to provide a rotary construction machine capable of reducing the size of the oil cooler and reducing the size of the oil cooler.

[0010]

SUMMARY OF THE INVENTION A swing construction machine according to the present invention comprises a lower traveling body and an upper revolving body which is pivotably mounted on the lower traveling body.

Then, in order to solve the above-mentioned problem,
A feature of the configuration adopted by the invention of claim 1 is that the upper revolving structure is mounted on the revolving frame and in a horizontal position extending to the left and right on the revolving frame at a rear side of the revolving frame. An engine provided with a cooling fan on one side in the left and right directions, a hydraulic pump mounted on the other side on the left and right sides of the engine, and an oil cooler provided near the cooling fan for cooling hydraulic oil A multiple valve device disposed on the revolving frame and connected to the hydraulic pump, a hydraulic oil tank disposed on the revolving frame for storing hydraulic oil supplied to the hydraulic pump, and the multiple valve A return pipe for returning hydraulic oil from the device via an oil cooler or directly to the hydraulic oil tank, wherein the return pipe has a flow direction of cooling air generated when the cooling fan is rotationally driven. Almost orthogonal In the provision of the heat radiating pipe portion extending in a direction.

With this configuration, the hydraulic oil returned from the multiple valve device to the hydraulic oil tank flows through the return pipe and is supplied to the oil cooler. At this time, the heat radiation pipe portion extending in a direction substantially perpendicular to the flow direction of the cooling air by the cooling fan receives the cooling air and releases the heat of the hydraulic oil, thereby lowering the temperature of the hydraulic oil. (Cooling capacity) can be reduced, and the oil cooler can be downsized.

According to the second aspect of the present invention, the heat radiating pipe portion of the return pipe is disposed substantially parallel to the oil cooler along the front or back surface of the oil cooler.

[0014] With this configuration, the heat radiation pipe portion of the return pipe can efficiently receive the cooling air passing through the oil cooler. Therefore, the working oil flowing through the heat radiation pipe portion is cooled by the cooling air. Can be.

According to the third aspect of the present invention, the cooling fan is
The present invention is configured as a discharge-type cooling fan that blows cooling air from the engine side toward the oil cooler when driven to rotate.

[0016] With this configuration, the cooling fan draws cool outside air around the engine and sends the outside air to the oil cooler as cooling air. Then, the cooling air whose temperature has increased through the oil cooler is discharged to the outside. As a result, the periphery of the engine is cooled by the cool outside air that is drawn.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A hydraulic shovel will be described as an example of a swing type construction machine according to an embodiment of the present invention, and will be described in detail with reference to FIGS. In the present embodiment, “front, rear” and “left, right” are used as meaning directions or positions viewed from an operator sitting in a driver's seat.

Reference numeral 1 denotes a lower traveling body of a hydraulic shovel, and 2 denotes an upper revolving body which is mounted on the lower traveling body 1 so as to be capable of turning. A working device 3 is provided.

Here, the working device 3 includes a lower boom 3A mounted on a revolving frame 4 to be described later so as to be capable of elevating, and an upper boom 3B mounted on the distal end of the lower boom 3A so as to be able to swing left and right. An arm retainer 3C attached to the tip of the upper boom 3B so as to swing leftward and rightward, an arm 3D attached to the arm retainer 3C so as to be able to move up and down, and a pivot at the tip of the arm 3D. It is roughly constituted by a bucket 3E mounted as possible. A link rod (not shown) that keeps the arm 3D always parallel to the lower boom 3A is rotatably connected between the lower boom 3A and the arm retainer 3C.

Further, the turning frame 4 and the lower boom 3A
, A boom cylinder 3F is provided, an arm cylinder 3G is provided between the arm retainer 3C and the arm 3D, and a bucket cylinder 3H is provided between the arm 3D and the bucket 3E. In addition, lower boom 3
An offset cylinder (not shown) is provided between A and the upper boom 3B.

On the other hand, as shown in FIG.
A turning frame 4, an engine 6, a cooling fan 7,
It is roughly constituted by a hydraulic pump 8, a radiator 9, an oil cooler 11, a multiple valve device 12, a hydraulic oil tank 13, a return pipe 18, and the like.

Reference numeral 4 denotes a revolving frame which constitutes a support structure for the upper revolving unit 2, and the revolving frame 4 is a flat bottom plate 4
A, and a pair of left and right vertical plates 4B, 4B which are erected upward from the bottom plate 4A and extend forward and backward. An arc-shaped counterweight 5 is attached to the rear end of the turning frame 4.

Reference numeral 6 denotes an engine mounted on the revolving frame 4. The engine 6 is located in front of the counterweight 5, and is disposed in a horizontal state extending leftward and rightward. Further, the engine 6 includes a water jacket (not shown) through which engine cooling water for cooling the engine 6 flows.

Reference numeral 7 denotes a cooling fan provided on the right side of the engine 6. The cooling fan 7 is disposed to face an oil cooler 11, which will be described later, and is driven to rotate by the engine 6. Here, when the cooling fan 7 is driven to rotate by the engine 6, as shown by an arrow in FIG.
The outside air sucked from the hydraulic pump side is circulated around the engine 6 as cooling air, and the radiator 9 and the oil cooler 1
It is configured as a so-called “discharge-type cooling fan” that blows air toward 1 and discharges it to the outside of an engine cover 22 described later.

Reference numeral 8 denotes a hydraulic pump mounted on the left side of the engine 6. The hydraulic pump 8 includes a main pump for supplying hydraulic oil for running the lower traveling body 1 and operating the working device 3, and a hydraulic pump 8 described later. And a pilot pump for supplying a pilot pressure for operating the multiple valve device 12.

Reference numeral 9 denotes a radiator disposed on the right side of the engine 6 near the cooling fan 7, and the radiator 9 is provided with a radiator 9 shown in FIG.
As shown in the figure, the upper tank portion 9A and the lower tank portion 9B
And a heat radiating portion 9C between the upper tank portion 9A and the lower tank portion 9B. An inflow hose 10 communicating with the water jacket of the engine 6 is connected to the upper tank 9A, and the engine cooling water cooled by the radiator 9C flows out to the water jacket of the engine 6 to the lower tank 9B. A side hose (not shown) is connected.

Reference numeral 11 denotes the left side of the radiator 9 (engine side).
The oil cooler 11 cools the hot working oil by the cylinders 3F, 3G, 3H of the working device 3, the hydraulic pump 8, and the like. The oil cooler 11 is connected to a return pipe 18 described later.

Numeral 12 denotes a multiple valve device located on the left side of the revolving frame 4 and in front of the hydraulic pump 8, and the multiple valve device 12 is constituted by a plurality of hydraulic pilot type switching valves. ing. The multiple valve device 12 is connected to the cylinders 3F, 3G, 3H of the working device 3, the hydraulic pump 8, the pilot valve (not shown), the oil cooler 11, the hydraulic oil tank 13, and the like.

Numeral 13 denotes a hydraulic oil tank located on the right side of the turning frame 4 and disposed in front of the radiator 9 and the oil cooler 11. The hydraulic oil tank 13 stores hydraulic oil supplied to the hydraulic pump 8. And connected to the hydraulic pump 8, the oil cooler 11, the multiple valve device 12, and the like. Further, on the lower surface side of the hydraulic oil tank 13, a supply pipe 1 described later is provided.
An outlet joint 13A to which the oil cooler 6 is connected is provided.
1 is connected to the inflow-side joint 13B. Reference numeral 14 denotes a fuel tank disposed in front of the hydraulic oil tank 13.

Here, a check valve 13C (shown in FIG. 4) is built in the inflow-side joint 13B of the hydraulic oil tank 13, and the check valve 13C has a high viscosity of the hydraulic oil due to a low temperature and has a high oil content. The valve is opened only when resistance when flowing through the cooler 11 is large, and hydraulic oil flows directly from the bypass pipe 21 into the hydraulic oil tank 13 without passing through the oil cooler 11.

Reference numeral 15 denotes a turning motor provided on the center side of the bottom plate 4A of the turning frame 4. The turning motor 15 constitutes a drive unit of a turning device for turning the upper turning body 2 with respect to the lower traveling body 1. It is.

On the other hand, reference numeral 16 denotes a supply pipe for supplying hydraulic oil from the hydraulic oil tank 13 to the hydraulic pump 8.
Has one end connected to the outflow side joint 13A of the hydraulic oil tank 13 and the other end connected to the hydraulic pump 8.

Reference numerals 17, 17,... Denote three connection hoses provided by connecting the hydraulic pump 8 and the multiple valve device 12. The connection hoses 17 are pressure oil discharged from the hydraulic pump 8, The pilot pressure is supplied to the multiple valve device 12.

Numeral 18 indicates the hydraulic oil tank 1 from the multiple valve device 12.
The return pipe 18 is an oil cooler inlet pipe 19 having one end connected to the multiple valve device 12 and the other end connected to the inlet of the oil cooler 11.
An oil cooler outlet pipe 20 having one end connected to the outlet side of the oil cooler 11 and the other end connected to an inlet joint 13B of the hydraulic oil tank 13, and an oil cooler inlet pipe 19 above the radiator 9. The hydraulic oil tank 13 is constituted by a bypass pipe 21 connecting the inflow side joint 13B.

Here, the oil cooler inlet pipe 19 is
An oblique pipe portion 19A extending obliquely from the multiple valve device 12 to the vicinity of the engine 6, and a straight pipe extending straight from the tip of the oblique pipe portion 19A to the left and right along the lower side of the engine 6. Portion 19B, a heat-radiating rising pipe portion 19C extending upward from the tip of the straight pipe portion 19B along the front of the radiator 9 almost in parallel with the radiator 9, and a radiator from the tip of the rising pipe portion 19C. 9 is connected to the upper surface side of the oil cooler 11 beyond the upper side of the oil cooler 9 and is constituted by a bent pipe portion 19D bent substantially in an L shape. The bypass pipe 21 described above is connected to the leading end side (upper side) of the rising pipe portion 19C. Here, the rising pipe portion for heat dissipation 19C corresponds to a heat dissipation pipe portion according to the present invention.

The rising pipe portion 19C is located downstream of the radiator 9, and is located above and below so as to be substantially perpendicular to the flow direction of the cooling air supplied by the cooling fan 7 (the direction indicated by the arrow in FIG. 2). Extending in the direction. Further, the rising pipe portion 19C is arranged at a position closer to the outer peripheral side of the cooling fan 7 where the cooling wind is strong.

When the operating oil having heat is returned to the multiple valve device 12 by the operation of the cylinders 3F, 3G, 3H of the working device 3, the hydraulic pump 8, etc. The operation oil is returned from the multiple valve device 12 to the operation oil tank 13. As a result, the hydraulic oil is supplied to the oil cooler inflow pipe 19 connected to the multiple valve device 12.
The oil flows into the oil cooler 11 and is cooled by the cooling air from the cooling fan 7 in the oil cooler 11. Then, the cooled hydraulic oil is returned to the hydraulic oil tank 13 via the oil cooler outlet pipe 20.

At this time, the cooling air generated by the cooling fan 7 passes through the oil cooler 11 and the radiator 9 and is supplied to the heat radiation rising pipe portion 19C of the oil cooler inflow pipe 19. Thereby, the working oil flowing through the rising pipe portion 19C can be cooled.

On the other hand, when the hydraulic oil returned from the multiple valve device 12 is cold, the viscosity of the hydraulic oil flowing through the oil cooler inlet pipe 19 is high, and the resistance when flowing through the oil cooler 11 increases. , Hydraulic oil is check valve 1
3C is opened, and returned to the hydraulic oil tank 13 directly from the bypass pipe 21.

Reference numeral 22 denotes an engine cover. The engine cover 22 includes an engine front cover 23 for covering the engine 6 from the upper side to the front side, the hydraulic oil tank 13 and the fuel tank 1.
The cover 6 includes a right cover 24 that covers the engine 4 and the like, a left cover (not shown) that covers the hydraulic pump 8 and the like, and a hood 25 that covers the rear side of the engine 6. The left cover is provided with an inlet for cooling air, and the right cover 24 is provided with an outlet (not shown) for cooling air. Further, skirt covers 26 and 27 that cover the periphery of the turning frame 4 are provided below the engine cover 22.

Reference numeral 28 denotes a driver's seat (shown in FIG. 1) on which an operator sits, and above the driver's seat 28 is a canopy 2.
9.

As described above, according to the present embodiment, the return pipe 18 for returning the hydraulic oil from the multiple valve device 12 to the hydraulic oil tank 13 is provided at the downstream side of the oil cooler inlet pipe 19 for heat radiation. The rising pipe section 1 is a pipe section 19C.
9C is disposed along the front of the radiator 9 and the oil cooler 11 so as to be orthogonal to the flow direction of the cooling air supplied from the cooling fan 7. Therefore, when the hot working oil is returned from the multiple valve device 12, the rising pipe portion 1
9C can cool this hydraulic oil by the cooling air of the cooling fan 7.

As a result, the working oil can be cooled by the return pipe 18 before the working oil is cooled by the oil cooler 11, so that the burden (cooling capacity) of the oil cooler 11 can be reduced. Moreover, the oil cooler 11 having a small cooling capacity, that is, a small one can be used. Thereby, the installation space of the oil cooler 11 can be reduced, and the arrangement around the engine 6 can be made flexible, and the cost can be reduced.

Further, by reducing the size of the oil cooler 11, the amount of use of the entire hydraulic oil can be reduced, so that the hydraulic oil tank 13 can be reduced in size.
Thereby, the hydraulic oil tank 13 can be efficiently arranged on the upper swing body 2, and the size of the upper swing body 2 can be reduced.

Further, since the heat radiation rising pipe portion 19C of the oil cooler inflow pipe 19 provided in the return pipe 18 is disposed in front of the radiator 9 and the radiator 9 downstream of the oil cooler 11, the cooling fan is provided. 7 can be reliably applied to the rising pipe 19C, and the cooling efficiency of the working oil by the rising pipe 19C can be increased. Moreover, the radiator 9 and the oil cooler 11
The cooling air after passing through the rising pipe section 19C is finally applied to the rising pipe section 19C for heat radiation.
Can prevent the cooling efficiency of the radiator 9 and the oil cooler 11 from being reduced.
The cooling performance of the oil cooler 11 can be stabilized at a high position.

Further, the cooling fan 7 is constituted as a discharge type cooling fan, and the radiator 9 and the oil cooler 11
Is supplied to the return pipe 18 after being cooled to a certain degree by passing through the pipe, so that when the work is performed in winter or the work site is in a cold region, the operating oil is warmed up by the warmed cooling air. Operability can be improved.

On the other hand, by using the discharge-type cooling fan 7, it is possible to supply cool outside air around the engine 6, so that the operator sitting on the driver's seat 28 arranged above the engine 6 can be cooled. , Heat can be prevented, and the working environment can be improved.

In the embodiment, the cooling fan 7 is
Although a case has been described as an example where the cooling fan is a discharge-type cooling fan that blows cooling air from the engine toward the radiator 9 and the oil cooler 11, the present invention is not limited to this. May be configured as a suction-type cooling fan that supplies cooling air to a radiator and an oil cooler by sucking air.

In the embodiment, the oil cooler 11
Has been described as being disposed adjacent to the engine side of the radiator 9, but instead, for example, the oil cooler 11
And the radiator 9 may be reversed in arrangement. In this case, the rising pipe portion 19C of the return pipe 18 is desirably arranged in front of the oil cooler 11.

Further, in the embodiment, the case where the rising pipe portion 19C of the oil cooler inlet side pipe 19 is disposed in front of the radiator 9 has been described as an example. However, the present invention is not limited to this. The rising pipe portion 19C may be arranged on the back of the radiator 9 or on the back of the oil cooler 11.

Further, in the embodiment, a small-sized hydraulic excavator has been described as an example of a swing type construction machine. However, the present invention is not limited to this, and other types of medium-sized and large-sized hydraulic excavators, hydraulic cranes and the like can be used. The present invention can also be applied to a swing type construction machine.

[0052]

As described above, according to the first aspect of the present invention, the cooling fan is provided in the return pipe for returning the hydraulic oil from the multiple valve device via the oil cooler or directly to the hydraulic oil tank. Since the heat radiation pipe portion extending in a direction substantially perpendicular to the flow direction of the cooling air generated when the rotary drive is performed is provided, the hydraulic oil returned from the multiple valve device to the hydraulic oil tank flows through the return pipe. It can be supplied to an oil cooler. At this time, since the heat radiation pipe portion extends in a direction substantially perpendicular to the flow direction of the cooling air flow from the cooling fan, it receives the cooling air and releases the heat of the hydraulic oil to lower the temperature of the hydraulic oil. it can.

As a result, the load (cooling capacity) of the oil cooler can be reduced and the oil cooler can be downsized. Therefore, the space for installing the oil cooler can be reduced to allow a degree of freedom in arrangement around the engine. And cost can be reduced. Further, by reducing the size of the oil cooler, the amount of use of the entire hydraulic oil can be reduced. Therefore, the hydraulic oil tank can be reduced in size, and the size of the upper swing body can be reduced.

According to the second aspect of the present invention, the heat radiating pipe portion of the return pipe is disposed substantially in parallel with the oil cooler along the front or back surface of the oil cooler. Can efficiently receive the cooling air passing through. Thereby, the working oil flowing through the heat radiating pipe portion can be efficiently cooled by the cooling air.

According to the third aspect of the present invention, the cooling fan is
Since the cooling fan is configured as a discharge type cooling fan that blows cooling air from the engine side to the oil cooler when rotating, the cooling fan draws cool outside air around the engine and uses this outside air as cooling air. The air can be blown toward the oil cooler, and the cooling air whose temperature has increased through the oil cooler can be discharged to the outside. Thus, the surroundings of the engine can be cooled by the cool outside air that is sucked in, so that the discomfort of the operator due to the heat of the engine can be prevented, and the working environment can be improved.

[Brief description of the drawings]

FIG. 1 is a front view showing a hydraulic shovel applied to an embodiment of the present invention.

FIG. 2 is a plan view showing the upper revolving structure with an engine cover, a floor plate, a driver's seat, and the like removed.

FIG. 3 is an enlarged front view showing a radiator, a hydraulic oil tank, a return pipe, and the like with an engine cover broken.

FIG. 4 is a system diagram showing a flow path of hydraulic oil.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Lower traveling body 2 Upper revolving superstructure 4 Revolving frame 6 Engine 7 Cooling fan 8 Hydraulic pump 9 Radiator 11 Oil cooler 12 Multiple valve device 13 Hydraulic oil tank 18 Return pipe 19 Oil cooler inflow side pipe 19C Rise pipe for heat radiation (heat radiation) Piping section) 20 oil cooler outlet pipe 21 bypass pipe

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Makoto Sugaya 650, Kandachicho, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery Co., Ltd.Tsuchiura Plant (72) Inventor Takeshi Hibiya 344-48 Kanegasaku, Matsudo-shi, Chiba (72) ) Inventor Yoshiro Takeuchi 1828 Shinji, Chiyoda-cho, Niiji-gun, Ibaraki F-term (reference) 2D015 BA01 CA02 3H089 BB21 BB27 CC01 DA02 DB32 DC04 GG02 JJ02

Claims (3)

[Claims] 1. A revolving construction machine comprising a lower traveling structure and an upper revolving structure pivotally mounted on the lower traveling structure, wherein the upper revolving structure includes a revolving frame and a rear side of the revolving frame. An engine which is mounted horizontally on the revolving frame and extends left and right on the revolving frame and has a cooling fan on one side in the left and right directions, and an engine on the other side in the left and right directions of the engine An attached hydraulic pump, an oil cooler provided in the vicinity of the cooling fan for cooling hydraulic oil, a multiple valve device disposed on the turning frame and connected to the hydraulic pump, and A hydraulic oil tank disposed therein for storing hydraulic oil to be supplied to the hydraulic pump, and a return pipe for returning the hydraulic oil from the multiple valve device to the hydraulic oil tank via an oil cooler or directly to the hydraulic oil pump, For plumbing, Pivoting construction machine, characterized in that a heat radiating pipe portion extending in a direction substantially perpendicular to the flow direction of the cooling air generated when the rotary driving the serial cooling fan. 2. The revolving construction machine according to claim 1, wherein the heat radiating pipe portion of the return pipe is disposed substantially in parallel with the oil cooler along a front surface or a rear surface of the oil cooler. 3. The swirling type cooling fan according to claim 1, wherein the cooling fan is configured as a discharge type cooling fan that blows cooling air from the engine side toward the oil cooler when the cooling fan is driven to rotate. Construction machinery.