JP2002161851A - Hydraulic pump device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the vibration of a hydraulic pipe passage in accordance with pulsation and ensure a large work space for maintenance and inspection around a hydraulic pump. SOLUTION: Pulsation reducing hoses 28, 30 are arranged in a condition in which they are along existing discharge hoses 26, 27, respectively, and are fixed to the discharge hoses 26, 27 using a hose clamp 32. Consequently, when, for example, a worker performs maintenance and inspection works for the hydraulic pump 22 in a building cover 8, the pulsation reducing hoses 28, 30 do not become obstacles so that a wide work space can be ensured around the hydraulic pump 22 to improve the workability of maintenance and inspection.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic pump device used for a construction machine such as a hydraulic shovel, and more particularly to a hydraulic pump device capable of reducing pulsation of a hydraulic pipe connected to a discharge side of a hydraulic pump. About.

[0002]

2. Description of the Related Art In general, a traveling or working hydraulic circuit or the like mounted on a construction machine such as a hydraulic excavator or a hydraulic crane is operated by a hydraulic pump driven by a prime mover and hydraulic oil discharged from the hydraulic pump. And a plurality of hydraulic pipelines connecting between the hydraulic actuators and the hydraulic pump.

Since hydraulic oil discharged from the hydraulic pump generates pulsation, among hydraulic lines connecting the hydraulic pump and the hydraulic actuator, in particular, a hydraulic line on the discharge side connected to the discharge port of the hydraulic pump ( The discharge hose) vibrates in accordance with the pulsation of the pressure oil flowing inside the discharge hose.

[0004] When the discharge hose vibrates due to the pulsation of the pressure oil, the vibration propagates to hydraulic equipment such as a control valve to which the discharge hose is connected and to a structure such as a turning frame supporting the discharge hose. There is a problem in that equipment and structures are damaged, and the working environment around the hydraulic pump is deteriorated due to noise caused by vibration.

On the other hand, the discharge port of the hydraulic pump is
It is known that the pulsation of the pressure oil flowing through the discharge hose can be reduced by connecting a pulsation reduction hose (hereinafter, referred to as a pulsation reduction hose) separately from the discharge hose (for example, see Japanese Unexamined Patent Application Publication No. Hei 8- 218426, etc.).

The pulsation reducing hose according to the prior art described above has a base end connected to the discharge side of the hydraulic pump and a distal end closed, and a part of the pressure oil discharged from the hydraulic pump is introduced. The distal end is fixed to a revolving frame or the like constituting an upper revolving unit of the hydraulic excavator via a bracket.

The pulsation reducing hose reflects the pressure oil introduced from the hydraulic pump at the closed end on the distal end side to return to the base end side, and merges with the pressure oil discharged into the discharge hose. A configuration in which the pulsation of the pressure oil returned to the base end side of the pulsation reduction hose and the pulsation of the pressure oil discharged into the discharge hose interfere with each other to cancel each other, thereby reducing the pulsation of the pressure oil flowing through the discharge hose. Has become.

[0008]

However, the pulsation reducing hose according to the prior art has a base end connected to the discharge side of the hydraulic pump and a distal end connected to a structure around the hydraulic pump such as a turning frame via a bracket or the like. It is configured to be fixed.

For this reason, for example, in order to perform maintenance and inspection work on the prime mover, the hydraulic pump, and the like, when the worker enters the building cover in which the prime mover, the hydraulic pump, and the like are housed, the worker places his or her feet on the pulsation reducing hose. There is a fear that the work space for maintenance and inspection in the building cover may be narrowed.

Further, for example, when the length of the pulsation reducing hose is changed in accordance with the pulsation of the pressure oil discharged from the hydraulic pump, the turning frame of the bracket interposed between the tip side of the pulsation reducing hose and the turning frame. Mounting position with respect to
It is necessary to change according to the length of the pulsation reducing hose, and there is a problem that the operation of changing the mounting position of the bracket is complicated.

Further, when the pulsation reducing hose vibrates due to the pulsation of the pressure oil discharged from the hydraulic pump, the vibration of the pulsation reducing hose propagates to the turning frame via the bracket, and is provided on the turning frame. There is a problem that the cab and the like generate vibration, noise, and the like.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and can reduce the vibration of a hydraulic pipeline due to pulsation during operation of a hydraulic pump. It is an object of the present invention to provide a hydraulic pump device capable of securing a large working space.

[0013]

According to a first aspect of the present invention, there is provided a hydraulic pump device which is driven by a prime mover and discharges high-pressure hydraulic oil.
A hydraulic line connected to the discharge side of the hydraulic pump and through which hydraulic oil discharged from the hydraulic pump flows, and a base end connected to the discharge side of the hydraulic pump and a distal end closed, and the hydraulic pump discharged from the hydraulic pump A pulsation reducing hose configured to reduce pulsation generated in the hydraulic line when a part of the pressure oil is introduced, wherein the pulsation reducing hose is arranged to extend along the hydraulic line; Is provided with a hose fixing member for fixing the pulsation reducing hose.

With this configuration, the pulsation reducing hose can be fixed to the hydraulic line using a hose fixing member while extending along the existing hydraulic line connected to the hydraulic pump. it can. For this reason, a large work space for maintenance and inspection can be secured around the hydraulic pump as compared with, for example, a case where the pulsation reducing hose is fixed to a structure disposed around the hydraulic pump. Further, by connecting the base end of the pulsation reducing hose to the discharge side of the hydraulic pump, it is not necessary to provide a branch pipe or the like for connecting the base end of the pulsation reducing hose, for example, at an intermediate position in the hydraulic pipeline. The structure of the entire hydraulic pump device can be simplified by eliminating the need for the branch pipe and the like.

According to a second aspect of the present invention, in the hose fixing member, the hose fixing member includes an elastic body which elastically sandwiches the hydraulic pipeline and the pulsation reducing hose.

With this configuration, the pulsation reducing hose can be fixed to the hydraulic line while the hydraulic line and the pulsation reducing hose are elastically held by the elastic body of the hose fixing member. Therefore, when the pulsation reducing hose vibrates due to the pulsation of the pressure oil, the transmission of the vibration of the pulsation reducing hose to the hydraulic pipeline can be suppressed by the elastic body.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a hydraulic pump device according to the present invention applied to a hydraulic shovel will be described in detail with reference to FIGS. 1 to 4. FIG.

In the drawing, reference numeral 1 denotes a hydraulic excavator, which comprises a crawler type lower traveling body 2 and a lower traveling body 2.
An upper revolving unit 4 is mounted on the upper revolving unit 4 so as to be revolvable via a revolving unit 3, and a working device 5 is provided on the front side of the upper revolving unit 4 so as to be able to move up and down.

Here, the upper revolving unit 4 includes a revolving frame 6
A cab 7 provided on the front left side of the turning frame 6 to define a driver's cab; a building cover 8 provided on the rear side of the cab 7; and a counter provided on the rear side of the building cover 8 The weight 9 is substantially used. As shown in FIGS. 2 and 3, a motor 10, a power transmission device 11, a hydraulic oil tank 12, a control valve group 13, a hydraulic pump device 21, and the like are housed in the building cover 8.

Reference numeral 10 denotes a prime mover located in front of the counterweight 9 and disposed inside the building cover 8, and 11 denotes a prime mover 1.
0, the power transmission device 11
Is for transmitting the power of the prime mover 10 to a hydraulic pump 22 described later.

Numeral 12 denotes a hydraulic oil tank located in front of the power transmission device 11 and disposed in the building cover 8. The hydraulic oil tank 12 is a hydraulic motor for traveling of the lower traveling body 2 and a hydraulic oil tank for the turning device 3. The hydraulic oil is supplied to various hydraulic actuators such as a hydraulic motor for turning and hydraulic cylinders of the working device 5.

Reference numeral 13 denotes a control valve group which is located in front of the prime mover 10 and is disposed in the building cover 8.
It is configured as an aggregate of a plurality of control valves for controlling the supply and discharge of the pressure oil to and from each of the hydraulic actuators described above. The input port of the control valve group 13 is connected to the hydraulic pump 22 via discharge hoses 26 and 27 described below, and the output port of each control valve constituting the control valve group 13 is connected via a hydraulic hose and the like. It is configured to be connected to each hydraulic actuator.

Reference numeral 21 denotes a hydraulic pump device according to the present embodiment, which is disposed in the building cover 8 together with the prime mover 10 and the like. The hydraulic pump device 21 includes a hydraulic pump 22, discharge hoses 26 and 27, which will be described later, and pulsation reduction. It is roughly constituted by hoses 28, 30 and the like.

Reference numeral 22 denotes a tandem type hydraulic pump mounted on the power transmission device 11 and driven by the prime mover 10.
The hydraulic pump 22 includes two pumps 22A and 22B arranged coaxially in a single casing. The pumps 22 </ b> A and 22 </ b> B operate in synchronism by transmitting the power of the prime mover 10 through the power transmission device 11, and use the hydraulic oil stored in the hydraulic oil tank 12 as high-pressure hydraulic oil to operate the respective hydraulic actuators. It is to be discharged toward.

Here, the hydraulic oil stored in the hydraulic oil tank 12 is supplied to the casing of the hydraulic pump 22 by the pump 2.
One suction port leading to 2A, 22B and pump 22
Two discharge ports (both not shown) for discharging the pressure oil from A and 22B are formed.

Reference numeral 23 denotes a hydraulic pump 22 and a hydraulic oil tank 12.
The suction pipe 23 has a base end connected to a suction port of a hydraulic pump 22 and a suction pipe 2.
3 is connected to the hydraulic oil tank 12. The suction pipe 23 guides the hydraulic oil in the hydraulic oil tank 12 to the suction port of the hydraulic pump 22 when the hydraulic pump 22 operates.

Reference numerals 24 and 25 denote piping connection blocks fixedly provided on the casing of the hydraulic pump 22. These piping connection blocks 24 and 25 constitute a part of the hydraulic pump 22. Here, the piping connection block 24
Of the two discharge ports provided on the casing of the hydraulic pump 22, the discharge port is connected to the discharge port on the pump 22A side, and the piping connection block 25 is connected to the discharge port on the pump 22B side.

The pipe connection block 24 is connected to the base ends of a discharge hose 26 and a pulsation reduction hose 28, which will be described later. The discharge hose 26 and the pulsation reduction hose 28 are formed in the pipe connection block 24. It is configured to communicate with a discharge port on the pump 22A side via an oil passage (not shown).

On the other hand, the base end sides of a discharge hose 27 and a pulsation reducing hose 30, which will be described later, are connected to the piping connection block 25, respectively. The discharge hose 27 and the pulsation reducing hose 30 are formed in the piping connection block 25. It is configured to communicate with a discharge port on the pump 22B side via an oil passage (not shown).

Reference numeral 26 denotes a piping connection block 24 and the control valve group 1
The discharge hose 26 is a high-pressure rubber hose having flexibility, and its base end is connected to a discharge port on the pump 22A side via a pipe connection block 24. Connected, control valve group 1 at the tip
3 input ports. And the pump 22
The pressure oil discharged from A is guided to an input port of the control valve group 13 through a discharge hose 26, and is supplied to a predetermined hydraulic actuator via a control valve constituting the control valve group 13. .

Reference numeral 27 denotes a piping connection block 25 and a control valve group 1
The discharge hose 27 is a high-pressure rubber hose having flexibility, and its base end is connected to a discharge port on the pump 22B side via a pipe connection block 25. Connected, control valve group 1 at the tip
3 input ports. And the pump 22
The pressure oil discharged from B is guided to the input port of the control valve group 13 through the discharge hose 27, and is supplied to a predetermined hydraulic actuator via the control valve constituting the control valve group 13. .

The control valve group 13 and the hydraulic oil tank 12 are connected via a return pipe (not shown), and return oil from each hydraulic actuator is supplied to the hydraulic oil tank through the return pipe. It is configured to recirculate into the inside of the fuel cell 12.

Reference numeral 28 denotes a pulsation reducing hose connected to the pipe connection block 24 together with the discharge hose 26. The pulsation reducing hose 28 is formed of a high pressure rubber hose.
When the base length is ４ wavelength of the pulsation of the pressure oil discharged from A, the length is formed as a natural number times the base length. Here, the pulsation reducing hose 28 is connected to the base 2 on the base end side.
8A is connected to the discharge port of the pump 22A using the piping connection block 24, and is arranged to extend along the discharge hose 26. A sealing plug 29 that closes the distal end of the pulsation reducing hose 28 is attached to the base 28B on the distal end side of the pulsation reducing hose 28. The base 28B is connected to the middle of the discharge hose 26 using a hose clamp 32 described later. It is fixed to the site.

The pulsation reducing hose 28 is connected to the pump 2
When a part of the pressure oil discharged from 2A is introduced, the pressure oil is reflected by the sealing plug 29 on the distal end side, returns to the base end side, and merges with the pressure oil discharged to the discharge hose 26. As a result, the pulsation of the pressure oil returned to the base end side of the pulsation reduction hose 28 and the pulsation of the pressure oil discharged to the discharge hose 26 interfere with each other and cancel each other, and the pulsation of the pressure oil flowing through the discharge hose 26 Is to be reduced.

Reference numeral 30 denotes a pulsation reducing hose connected to the piping connection block 25 together with the discharge hose 27. The pulsation reducing hose 30 is formed of a high-pressure rubber hose.
When the basic length is １ ／ wavelength of the pulsation of the pressure oil discharged from B, the length is formed as a natural number times the basic length. Here, the pulsation reducing hose 30 is connected to the base 3 on the base end side.
0A is connected to the discharge port on the pump 22B side by using the piping connection block 25, and is disposed so as to extend along the discharge hose 27. The base 30B on the tip side of the pulsation reducing hose 30 is closed by a sealing plug 31, and the base 30B is fixed to an intermediate portion of the discharge hose 27 using a hose clamp 32.

Similarly to the pulsation reducing hose 28, the pulsation reducing hose 30 reflects a part of the pressure oil discharged from the pump 22B by the sealing plug 31 on the distal end side and returns it to the base end side. The pulsation of the pressure oil flowing through the discharge hose 27 is reduced by merging with the pressure oil discharged to the discharge hose 27.

Hose clamps 32 are provided as hose fixing members provided in the middle of the discharge hoses 26 and 27, respectively.
The pulsation reducing hoses 28, 30 are fixed to the pulsation reducing hoses 6, 27. The hose clamp 32 includes an elastic body 33, a holding plate 34, a spacer 35, a bolt 36, a nut 37, and the like, which will be described later, as shown in FIG.

Reference numerals 33, 33 denote elastic bodies which elastically clamp the middle part of the discharge hose 26 and the base 28B on the tip side of the pulsation reducing hose 28 from above and below.
Is formed in a substantially rectangular parallelepiped shape by, for example, hard rubber or the like. Here, spacer insertion holes 33A, 33A into which the spacers 35 are inserted are formed at both ends in the length direction of the elastic body 33, and a half-hole for fitting to the discharge hose 26 is provided between the spacer insertion holes 33A. An arc-shaped recess 33B and a semi-arc-shaped recess 33C fitted into the mouthpiece 28B of the pulsation reducing hose 28
Are formed.

Reference numerals 34, 34 denote holding plates for holding the elastic members 33 from above and below. The holding plates 34 are formed in a rectangular shape from, for example, a steel plate or the like. Bolt insertion holes 34A, 34A into which the bolts 36 are inserted are formed at both ends in the corresponding length direction.

Numerals 35, 35 are cylindrical spacers inserted into the respective spacer insertion holes 33A of the elastic body 33. Both ends in the length direction of the spacer 35 are in contact with the holding plate 34.
And each spacer 35 sets the interval of the holding plate 34,
When each elastic body 33 is fastened using a bolt 36 or the like,
This prevents excessive fastening force from acting on these elastic bodies 33.

Reference numerals 36, 36 denote bolts for fastening the upper and lower elastic members 33 via the holding plate 34. The bolt 36 is inserted into the bolt insertion hole 34A of the holding plate 34 and the spacer 35, and An upper and lower elastic body 33 is fastened between the holding plates 34 by screwing a nut 37 to a male thread portion of a bolt 36 protruding from the holding plate 34.

As described above, the hose clamp 32 fixes the base 28B to the discharge hose 26 in a state where the discharge hose 26 and the base 28B on the tip side of the pulsation reducing hose 28 are elastically held by the elastic body 33. are doing. On the other hand, similarly, the hose clamp 32 fixes the base 30B to the discharge hose 27 in a state where the discharge hose 27 and the base 30B on the tip side of the pulsation reducing hose 30 are elastically sandwiched by the elastic body 33. are doing.

The hydraulic pump device 21 according to the present embodiment has the above-described configuration, and its operation will be described below.

First, when the prime mover 10 operates, the pumps 22A and 22B of the hydraulic pump 22 are driven synchronously.
As a result, the hydraulic oil in the hydraulic oil tank 12 is sucked into the pumps 22A and 22B through the suction pipe 23, and the pumps 22A and 22B pressurize the sucked hydraulic oil and discharge the pressurized oil to the respective discharge ports.

Most of the pressure oil discharged from the pump 22A is guided to the control valve group 13 through the discharge hose 26 connected to the pipe connection block 24, and the control valve group 1
3 to a predetermined hydraulic actuator. On the other hand, most of the pressure oil discharged from the pump 22B is guided to the control valve group 13 through the discharge hose 27 connected to the pipe connection block 25, and supplied to other hydraulic actuators via the control valve group 13. You.

At this time, a part of the pressure oil discharged from the pump 22A is introduced into the pulsation reducing hose 28 and the sealing plug 29
The pulsation of the pressure oil flowing through the discharge hose 26 can be reduced by merging with the pressure oil discharged into the discharge hose 26. On the other hand, a part of the pressure oil discharged from the pump 22B is introduced into the pulsation reduction hose 30, reflected by the sealing plug 31, and merges with the pressure oil discharged into the discharge hose 27, so that the inside of the discharge hose 27 is discharged. The pulsation of the flowing pressure oil can be reduced.

In this case, the pulsation reducing hose 28 is arranged so as to extend along the discharge hose 26, and the base 28 B on the tip side is connected to the discharge hose 26 by the hose clamp 32.
It is fixed to. The pulsation reducing hose 30 is arranged so as to extend along the discharge hose 27, and the base 30 B on the distal end is connected to the discharge hose 2 by the hose clamp 32.
7 is fixed.

As described above, according to the hydraulic pump device 21 of the present embodiment, the pulsation reducing hoses 28, 30 can be fixed along the existing discharge hoses 26, 27, respectively. A pulsation reducing hose 2 is attached to a structure such as the turning frame 6 existing around the pump 22.
There is no need to fix 8,30.

For this reason, for example, when an operator performs maintenance and inspection work on the hydraulic pump 22 and the like in the building cover 8, the pulsation reducing hoses 28 and 30 are not obstructed, and are wide around the hydraulic pump 22. Work space can be secured, and workability during maintenance and inspection can be improved.

Further, by fixing the pulsation reducing hoses 28, 30 to the discharge hoses 26, 27 using the hose clamp 32, for example, it is necessary to fix the pulsation reducing hoses 28, 30 to the turning frame 6 via a bracket or the like. Disappears. Therefore, even if the pulsation reducing hoses 28, 30 vibrate due to the introduction of the pressure oil discharged from the pumps 22A, 22B, the vibrations of the pulsation reducing hoses 28, 30 do not propagate to the turning frame 6. The vibration of the cab 7 and the like provided on the revolving frame 6 can be suppressed.

Also, for example, even if the length of the pulsation reducing hoses 28, 30 is changed, the mounting position of the hose clamp 32 with respect to the discharge hoses 26, 27 can be changed.
27 only by moving it in the length direction.
The pulsation reducing hoses 28 and 30 can be easily fixed by utilizing the 27.

For this reason, as compared with a configuration in which the pulsation reducing hose is fixed using a bracket mounted on the turning frame as in the prior art, for example, the mounting position of the bracket with respect to the turning frame according to the change in the length of the pulsation reducing hose. It is not necessary to perform complicated operations such as changing

Further, the hydraulic pump device 21 according to the present embodiment is configured such that the pulsation reducing hose 28 has a base end side (the base 28).
A) is connected to the discharge side of the pump 22A using the piping connection block 24 for the discharge hose 26 provided in the hydraulic pump 22, and the base end (the base 30) of the pulsation reducing hose 30 is connected.
A) is connected to the discharge side of the pump 22B using a piping connection block 25 for the discharge hose 27 provided in the hydraulic pump 22.

Thus, for example, the discharge hoses 26, 27
It is not necessary to provide a bifurcated branch pipe or the like for connecting the base end sides of the pulsation reducing hoses 28 and 30 at an intermediate position of the hydraulic pump device 21. The entire structure of the hydraulic pump device 21 is equivalent to the need for these branch pipes and the like. Can be simplified, which can contribute to a reduction in manufacturing cost.

Further, since the hose clamp 32 includes the elastic body 33 which elastically sandwiches the discharge hose 26 (27) and the pulsation reducing hose 28 (30), the hose clamp 32 is The transmission of vibration to the discharge hoses 26 and 27 can be suppressed by the elastic body 33. Further, when the pulsation reducing hoses 28, 30 vibrate, it is possible to prevent the pulsation reducing hoses 28, 30 from being damaged by friction with the holding plate 34 or the like.

In the above-described embodiment, a case where a tandem-type hydraulic pump 22 having two pumps 22A and 22B in the same casing is used as a hydraulic pump constituting a hydraulic pump device will be described as an example. Although described above, the present invention is not limited to this, and can be applied to, for example, a hydraulic pump device having one hydraulic pump or a hydraulic pump device having three or more hydraulic pumps.

Further, in the above-described embodiment, the case where the hydraulic pipeline through which the pressure oil discharged from the hydraulic pump 22 flows is constituted by the discharge hoses 26 and 27 made of rubber hoses has been described as an example. However, the present invention is not limited to this, and may be configured by a discharge pipe made of a metal pipe or the like.

In the above-described embodiment, the hydraulic pump device mounted on the hydraulic excavator has been described as an example. However, the present invention is not limited to this. The present invention can be widely applied to a hydraulic pump device mounted on a construction machine or a hydraulic pump device used for various industrial machines other than the construction machine.

[0059]

As described above in detail, according to the first aspect of the present invention, the pulsation reducing hose is arranged along the hydraulic line, and the pulsation reducing hose is connected to the hydraulic line by using a hose fixing member. With the fixed configuration, the pulsation reduction hose can be fixed by using the existing hydraulic pipeline connected to the hydraulic pump. For example, the pulsation reduction hose is fixed to a structure arranged around the hydraulic pump. A larger work space for maintenance and inspection can be secured around the hydraulic pump as compared with the case where the above is performed. Further, compared with a case where the pulsation reducing hose is fixed to a structure disposed around the hydraulic pump, for example, the vibration of the pulsation reducing hose can be suppressed from propagating to the structure.

In addition, since the base of the pulsation reducing hose is connected to the discharge side of the hydraulic pump, for example, a branch pipe or the like for connecting the base of the pulsation reducing hose to an intermediate portion of the hydraulic pipeline. Need not be provided, and the structure of the entire hydraulic pump device can be simplified by eliminating the need for the branch pipe and the like.

According to the second aspect of the present invention, since the hose fixing member includes an elastic body which elastically sandwiches the hydraulic pipeline and the pulsation reducing hose, the pulsation reducing hose is caused by the pulsation of the pressure oil. When vibrated, transmission of the vibration of the pulsation reducing hose to the hydraulic pipeline can be suppressed by the elastic body. Further, when the pulsation reducing hose is vibrated by vibration, it is possible to suppress the pulsation reducing hose from being damaged by friction.

[Brief description of the drawings]

FIG. 1 is a front view showing a hydraulic excavator to which a hydraulic pump device according to the present invention is applied.

FIG. 2 is an enlarged cross-sectional view of a hydraulic pump, a discharge hose, a pulsation reducing hose, a hose clamp, and the like, as viewed from the direction of arrows II-II in FIG.

FIG. 3 is an enlarged sectional view of a hydraulic pump, a discharge hose, a pulsation reducing hose, a hose clamp, and the like, as viewed from a direction indicated by arrows III-III in FIG.

FIG. 4 is an enlarged cross-sectional view of a discharge hose, a pulsation reducing hose, a hose clamp, and the like, as viewed from a direction indicated by arrows IV-IV in FIG.

[Explanation of symbols]

 Reference Signs List 10 motor 21 hydraulic pump device 22 hydraulic pump 23 suction pipe 24, 25 pipe connection block 26, 27 discharge hose (hydraulic pipeline) 28, 30 pulsation reduction hose 28A, 30A base part (base end side) 28B, 30B base part ( Tip side) 32 Hose clamp (Hose fixing member) 33 Elastic body

 ──────────────────────────────────────────────────続 き Continued on front page F-term (reference) 2D012 EA01 2D015 BA01 3H071 AA01 CC25 DD36 3H075 CC17 CC19 CC35

Claims (2)

[Claims] A hydraulic pump driven by a prime mover for discharging high-pressure hydraulic oil, a hydraulic line connected to a discharge side of the hydraulic pump, and through which hydraulic oil discharged from the hydraulic pump flows.
A pulsation reducing hose that has a base end connected to the discharge side of the hydraulic pump and has a distal end closed, and a pulsation generated in the hydraulic pipeline due to introduction of a part of the pressure oil discharged from the hydraulic pump; A hydraulic pump device comprising: a pulsation reducing hose arranged so as to extend along the hydraulic pipeline, and a hose fixing member for fixing the pulsation reducing hose is provided in the hydraulic pipeline. 2. The hydraulic pump device according to claim 1, wherein the hose fixing member includes an elastic body that elastically sandwiches the hydraulic pipeline and the pulsation reducing hose.