WO2016098999A1

WO2016098999A1 - Hydraulic pump

Info

Publication number: WO2016098999A1
Application number: PCT/KR2015/009310
Authority: WO
Inventors: 강병익; 이성춘; 문병춘; 조준연
Original assignee: 현대중공업 주식회사
Priority date: 2014-12-19
Filing date: 2015-09-03
Publication date: 2016-06-23
Also published as: KR20160075931A

Abstract

A hydraulic pump, according to the present invention, has a symmetric section formed for as much as a preset interval from a kidney hole, and a gradual curve section formed after the preset interval up to a fluid discharge hole, thereby effectively reducing the magnitude of stress applied to a fluid discharge flow channel, thus having the effect of enhancing durability, and having the effect of reducing the cost of the product since additional machining after casting may be reduced.

Description

Hydraulic pump

The present invention relates to a hydraulic pump.

A hydraulic pump is a basic power source of a hydraulic system that operates a hydraulic motor or a cylinder by receiving mechanical energy obtained from an electric motor or an engine and giving a fluid energy of pressure and flow rate to the fluid. Hydraulic pumps include fixed-capacity pumps (pumps that cannot vary in discharge rate per revolution) and variable displacement pumps (pumps that can vary in discharge rate per revolution). ought.

The fixed capacity pump pumps and discharges the fluid by changing the flow rate of the sealed oil chamber, and the suction and discharge sides are separated so that the discharge amount of the pump is almost constant even if the load fluctuates and the discharge pressure of the pump changes. Suitable for the device.

In the fixed-capacity type pump, as the engine RPM increases, the flow rate of the fluid increases proportionally, and in the engine RPM region, the flow rate is generated more than necessary to increase the pressure of the fluid driving system, and the pump is driven with the increased pressure. There is a downside to using additional engine power.

Therefore, in order to prevent power loss due to excessive fluid pressure generation and to improve fuel efficiency, and to compensate for the above disadvantages, a variable displacement pump which adjusts the flow rate discharged from the pump according to the engine RPM is mainly used. .

Variable displacement pump is a pump that can change the capacity of the pump from the minimum to the maximum. When the cylinder itself rotates in the case of the pump as the pump shaft rotates, the piston rotates with the cylinder and the piston reciprocates. As the inclined plate is inclined, the stroke of the piston is changed to change the amount of fluid discharged from the pump.

However, even in the use of such a variable displacement pump, the durability is easily lowered by the operation of compressing and discharging the fluid at a high pressure, which requires a lot of maintenance, resulting in an increase in cost.

The present invention has been made to solve the problems of the prior art as described above, an object of the present invention, to reduce the stress applied to the internal components of the pump by the high pressure fluid to improve the durability and to improve the durability after casting machine It is to provide a hydraulic pump for reducing the production cost by reducing the amount of processing.

Hydraulic pump according to an embodiment of the present invention, the first hydraulic pump provided on one side to compress the fluid; A second hydraulic pump provided on the other side to compress the fluid; And a valve block provided between the first hydraulic pump and the second hydraulic pump, wherein the valve block is configured to discharge a fluid compressed therein from the first hydraulic pump or the second hydraulic pump to the outside. A discharge flow path, the fluid discharge flow path comprising: a discharge side kidney hole connected to the first hydraulic pump or the second hydraulic pump; A discharge hole connected to the outside; And a connection part connecting the discharge side kidney hole and the discharge hole, wherein the connection part is formed symmetrically with respect to a center line at least partially bisecting the upper and lower sides.

In detail, the connection part is connected to the discharge-side kidney hole, and the curvature direction of the upper curve and the curvature direction of the lower curve are opposite to each other, and are connected to each other in a vertical symmetry with respect to a center line dividing the upper and lower sides. part; And a connection second part connecting the connection first part and the discharge hole and having the same curvature direction of the upper curve and the curvature direction of the lower curve.

Specifically, the connecting first part may occupy 30% to 40% of the connection part.

Specifically, the fluid discharge passage, the first fluid discharge passage for discharging the fluid compressed in the first hydraulic pump to the outside; And a second fluid discharge passage configured to discharge the fluid compressed by the second hydraulic pump to the outside, wherein the first fluid discharge passage comprises: a discharge side first kidney hole connected to the first hydraulic pump; A first discharge hole connected to the outside and provided at an upper side of the valve block at a center line dividing the upper and lower sides of the valve block; And a first connection part connecting the discharge side first kidney hole and the first discharge hole, wherein the second fluid discharge flow path comprises: a discharge side second kidney hole connected to the second hydraulic pump; A second discharge hole connected to the outside and provided at a lower side with respect to a center line bisecting the upper and lower sides of the valve block; And a second connection part connecting the discharge side second kidney hole and the second discharge hole.

Specifically, the first connection portion is connected to the discharge side first kidney hole, the curvature direction of the upper curve and the curvature direction of the lower curve are formed in reverse, it is formed up and down symmetrically with respect to the center line bisecting the upper and lower (up and down) A first connection first portion; And a first connecting second part connecting the first connecting first part and the first discharge hole and having the same curvature direction of the upper curve and the curvature direction of the lower curve, wherein the second connecting part includes: A second connection first part connected to the discharge-side second kidney hole, the curvature direction of the upper curve and the curvature direction of the lower curve being opposite to each other, the second connecting first part being symmetrical with respect to the center line dividing the upper and lower parts; And a second connection second part connecting the second connection first part and the second discharge hole and having the same curvature direction of the upper curve and the curvature direction of the lower curve.

In detail, the first fluid discharge channel and the second fluid discharge channel may be formed with point symmetry with respect to each other based on a center point bisecting between the first discharge hole and the second discharge hole.

Specifically, the valve block may include a fluid inlet for supplying a fluid to the first hydraulic pump or the second hydraulic pump, and the fluid discharge part may be located opposite to the fluid inlet.

In the hydraulic pump according to the present invention, the two discharge holes through which the fluid compressed at high pressure is discharged are disposed up and down instead of left and right, thereby maximizing space utilization by reducing the size of the hydraulic pump, valve block and left and right hydraulic pumps. There is an effect of increasing the bolting safety with the.

In addition, the hydraulic pump according to the present invention is arranged so that the position of the flow path supplied to the regulator is branched on the straight flow path supplied to the sensor, the branching point (flow cross point) is reduced to one on the fluid discharge flow path to improve the durability In addition, the stress that the branch point is branched on the straight flow path is smaller and there is an effect of maximizing durability.

In addition, the hydraulic pump according to the present invention is formed in the symmetrical interval from the Kidney hole by the predetermined interval, and formed in a gentle curved interval from the predetermined interval to the fluid discharge hole, thereby to determine the magnitude of the stress received by the fluid discharge passage It effectively reduces durability, and can reduce additional machining after casting, reducing the cost of the product.

In addition, the hydraulic pump according to the present invention, the curvature is formed in the connection point on the linear flow path and the straight flow path of the flow path of the fluid in the hydraulic pump, it is possible to prevent the phenomenon that the stress is concentrated on the connection point is improved durability There is an effect, by forming the casting shape with a curvature during manufacturing, it is possible to reduce the additional machining, thereby reducing the cost of the product.

1 is a cross-sectional view showing a cross section of a hydraulic pump.

Figure 2a is a perspective view showing a valve block of the hydraulic pump according to the first embodiment of the present invention.

Figure 2b is a rear view showing a valve block of the hydraulic pump according to the first embodiment of the present invention.

3A is a conceptual diagram illustrating the inside of a valve block of a hydraulic pump according to a second exemplary embodiment of the present invention.

3B is a conceptual diagram illustrating a kidney hole of a valve block of a hydraulic pump according to a second exemplary embodiment of the present invention.

Figure 4a is an internal conceptual view showing the interior of the valve block of the conventional hydraulic pump.

Figure 4b is an internal conceptual view showing the inside of the valve block of the hydraulic pump according to the third embodiment of the present invention.

5A is a conceptual diagram illustrating a connection state of a fluid main discharge passage and a sensor fluid supply passage of a valve block of a hydraulic pump according to a fourth exemplary embodiment of the present invention.

5B is a conceptual diagram illustrating a connection state between a sensor fluid supply channel and a regulator fluid supply channel of the valve block of the hydraulic pump according to the fourth embodiment of the present invention.

FIG. 6A is a structural analysis result diagram showing a structural analysis result showing a state of stress received by a kidny hole when a conventional hydraulic pump is driven. FIG.

FIG. 6B is a structural analysis result diagram showing a structural analysis result showing a state of stress received by a kidny hole when driving a hydraulic pump according to an exemplary embodiment of the present invention. FIG.

The objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and the preferred embodiments associated with the accompanying drawings. In the present specification, in adding reference numerals to the components of each drawing, it should be noted that the same components as possible, even if displayed on different drawings have the same number as possible. In addition, in describing the present invention, if it is determined that the detailed description of the related known technology may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a cross-sectional view showing a cross section of a hydraulic pump. Before describing the embodiment of the present invention will be described schematically for the hydraulic pump (1). Here, the hydraulic pump 1 shown in FIG. 1 is a two-stage variable flow piston type pump, but this is only one example for describing the hydraulic pump 1 according to the embodiment of the present invention, but is not limited thereto.

As shown in FIG. 1, the hydraulic pump 1 includes a drive shaft 10, a first hydraulic pump 100, a second hydraulic pump 200, a pilot pump 300, and a valve block 400. .

The hydraulic pump 1 is a first hydraulic pump 100 provided on one side to compress the fluid and a second hydraulic pump 200 provided on the other side to compress the fluid, ie, two piston pumps of left and right symmetry. It consists of the 1st hydraulic pump 100 and the 2nd hydraulic pump 200. As shown in FIG. In this case, the valve block 400 may be positioned between the first hydraulic pump 100 and the second hydraulic pump 200 to couple the first hydraulic pump 100 and the second hydraulic pump 200 to each other.

In the first hydraulic pump 100 and the second hydraulic pump 200, the

cylinder blocks

113 and 213 in which the plurality of

pistons

112 and 212 are radially inserted and the

piston shoes

114 and 214 connected to the

pistons

112 and 212 are closely attached to each other. It consists of a swash plate (111,211) that can adjust the maximum and minimum flow rate, there is a screw (not shown) to adjust the angle of the swash plate (111,211), cylinder block (113,213) and swash plate (111,211) Is configured to penetrate by the drive shaft 10.

The

swash plates

111 and 211 are fixed at a set angle without rotation, and when the

pistons

112 and 212 rotate by the rotation of the drive shaft 10, the

pistons

112 and 212 slide along the

swash plates

111 and 211, and

cylinder blocks

113 and 213. Will reciprocate in the axial direction within the cylinder.

The first hydraulic pump 100 and the second hydraulic pump 200 are connected and fixed by the valve block 400, and are coupled by bolting. The valve block 400 may supply a fluid flowing into the

pumps

100 and 200, and discharge the fluid compressed and discharged from the

pumps

100 and 200 to the outside.

The pilot pump 300 refers to a pump for circulating a fluid in a pilot circuit (not shown). The pilot pump 300 is located on one side (preferably the right side) of the second hydraulic pump 200, and may be a gear type.

Hereinafter will be described in detail with respect to the contents of the present invention improved on the basis of the hydraulic pump (1) described above.

2A is a perspective view illustrating a valve block of the hydraulic pump according to the first embodiment of the present invention, and FIG. 2B is a rear view illustrating the valve block of the hydraulic pump according to the first embodiment of the present invention.

As shown in FIGS. 2A and 2B, the valve block 400 of the hydraulic pump 1 according to the first embodiment of the present invention includes a valve block right side 410, a valve block rear side 420, and a valve block And a seat face part 430 and a valve block front part 440.

The hydraulic pump 1 according to the present invention uses the same reference numerals for convenience of each configuration in the hydraulic pump 1 described in FIG. 1, but does not necessarily refer to the same configuration.

The valve block right surface part 410 is located on the right side of the valve block 400 and may be connected to the second hydraulic pump 200. The valve block right surface portion 410 has a central portion penetrated by the drive shaft 10 and is in contact with the second hydraulic pump 200, such as components of the second hydraulic pump 200 (for example, a cylinder block ( 213 or valve plate (not shown) is formed to be connected.

In detail, the valve block right surface portion 410 has a drive shaft through hole 413 penetrating the drive shaft 10 at a central portion thereof, and has a suction side second kidney hole (1) around the drive shaft through hole 413. The discharge side second kidney hole 412 is formed at the other side 411. The suction side second kidney hole 411 is a hole for supplying the fluid from the outside (preferably a hydraulic storage tank (not shown)) to the second hydraulic pump 200, and the discharge side second kidney hole ( 412 is a hole for discharging the fluid compressed by the second hydraulic pump 200 to the outside (preferably a working device (not shown) using the compressed fluid).

The valve block right surface portion 410 may include a second hydraulic pump-first bolting engagement portion 481a which binds an upper portion of the valve block 400 to bind the second hydraulic pump 200 to the valve block 400. And a second hydraulic pump-second bolting fastening portion 482a for fastening the central portion of the valve block 400 and a second hydraulic pump-third bolting fastening portion 483a for fastening the lower portion of the valve block 400. can do.

In this case, the second hydraulic pump-second bolting fastening part 482a may be disposed between the first hydraulic pump fluid discharge hole 421 and the second hydraulic pump fluid discharge hole 422 formed in the valve block rear surface part 420 to be described later. It can be located at

The valve block rear part 420 is located on the opposite side of the valve block front part 440 which will be described later, that is, at the rear side of the valve block 400, and is compressed by the first hydraulic pump 100 and the second hydraulic pump 200. Can be discharged to the outside (preferably a working device using a compressed fluid).

The valve block rear part 420 discharges the fluid compressed by the first hydraulic pump fluid discharge hole 421 and the second hydraulic pump 200 to discharge the compressed fluid from the first hydraulic pump 100 to the outside. The second hydraulic pump fluid discharge hole 422 may be included.

In this case, the first hydraulic pump fluid discharge hole 421 is configured to be located above the valve block rear part 420, and the second hydraulic pump fluid discharge hole 422 is located below the valve block rear part 420. Can be configured. This means that the first hydraulic pump fluid discharge hole 421 may be configured to be spaced apart from each other vertically with the second hydraulic pump fluid discharge hole 422, and the first hydraulic pump fluid discharge hole 421 must be disposed. Is located at the upper side, and the second hydraulic pump fluid discharge hole 422 is not limited to be positioned at the lower side.

The first hydraulic pump fluid discharge hole 421 and the second hydraulic pump fluid discharge hole 422 may be provided at positions symmetrical with each other with respect to the center of the valve block rear surface part 420. Specifically, the valve block The rear portion 420 may be provided at positions symmetric to each other based on a center line dividing the upper and lower portions.

Conventionally, the first hydraulic pump fluid discharge hole and the second hydraulic pump fluid discharge hole are horizontally disposed at left and right positions, so that the length of the valve block is long, so that the length of the entire hydraulic pump is long. Since the hydraulic pump fluid discharge hole 421 and the second hydraulic pump fluid discharge hole 422 are provided at the upper and lower positions, the overall size of the hydraulic pump 1 can be reduced (specifically, the horizontal length is effectively reduced. This has the effect of maximizing the space utilization of machines driven by hydraulics (preferably construction equipment; not shown).

The first hydraulic pump fluid discharge hole 421 and the second hydraulic pump fluid discharge hole 422 are bolted to fasten the first hydraulic pump 100 and the second hydraulic pump 200 to the valve block 400. Parts (first hydraulic pump-second bolting fastening part (not shown) and second hydraulic pump-second bolting fastening part 482a) are configured in the valve block right surface part 410 and the valve block left surface part 430. It may be configured to be spaced apart from the upper side and the lower side so as to be possible.

That is, between the first hydraulic pump fluid discharge hole 421 and the second hydraulic pump fluid discharge hole 422, the first hydraulic pump-second bolting fastening part and the second hydraulic pump-second bolting fastening part 482a. ) May be formed.

Conventionally, the first hydraulic pump fluid discharge hole and the second hydraulic pump fluid discharge hole are horizontally disposed at left and right positions, and the first side of the valve block rear portion binds the first hydraulic pump 100 and the second hydraulic pump 200. Could not form a bolted fastening portion, there was a problem that the binding force between the first hydraulic pump 100 and the second hydraulic pump 200 is small.

Accordingly, in the first embodiment of the present invention, the first hydraulic pump-second bolting fastening portion and the second hydraulic pump-between the first hydraulic pump fluid discharge hole 421 and the second hydraulic pump fluid discharge hole 422. By generating a free space in which the second bolting fastening part 482a can be formed, more bolting fastening parts capable of binding the first hydraulic pump 100 and the second hydraulic pump 200 are formed than in the prior art ( In the embodiment of the present invention, six bolting fastening portions are formed by binding not only the upper side and the lower side but also the center side). The binding force of the first hydraulic pump 100 and the second hydraulic pump 200 is maximized.

The valve block seating surface 430 is located on the left side of the valve block 400 and may be connected to the first hydraulic pump 100. The valve block seating surface 430 has a central portion penetrated by the driving shaft 10 and is in contact with the first hydraulic pump 100. 113) or a valve plate (not shown) is formed to be connected.

Specifically, the valve block seating surface 430 has a drive shaft through hole (not shown) formed in the center of the valve block seating surface 430, and the suction side first kidney hole (not shown) around the drive shaft through hole. (Not shown) and the discharge side first Kidney hole (not shown) are formed. The suction side first kidney hole is a hole for supplying fluid from the outside (preferably a hydraulic storage tank (not shown)) to the first hydraulic pump 100, and the discharge side first kidney hole is the first A hole for discharging the fluid compressed by the hydraulic pump 100 to the outside (preferably a working device (not shown) using the fluid).

The valve block seating surface 430 may include a first hydraulic pump-first bolting fastening portion 481b which binds an upper portion of the valve block 400 to bind the first hydraulic pump 100 to the valve block 400. , The first hydraulic pump-second bolting fastening part (not shown) for binding the central portion of the valve block 400 and the first hydraulic pump-third bolting fastening part 483b for fastening the lower portion of the valve block 400. It may include.

In this case, the first hydraulic pump-second bolting fastening part may be positioned between the first hydraulic pump fluid discharge hole 421 and the second hydraulic pump fluid discharge hole 422 formed in the valve block rear surface part 420.

The valve block front part 440 is located on the opposite side of the valve block rear part 420, that is, on the front side of the valve block 400, and receives the fluid from the outside (preferably a hydraulic oil storage tank) to receive the first hydraulic pump ( 100) and the second hydraulic pump 200 may be supplied.

Specifically, the valve block front part 440 may include a fluid inflow passage 441 for receiving fluid from the outside and supplying the fluid to the first hydraulic pump 100 and the second hydraulic pump 200. The flow path 441 may be formed in the center of the valve block front part 440 in the form of a through hole and connected to the suction side first kidney hole and the suction side second kidney hole 411.

As described above, the hydraulic pump 1 according to the present invention arranges two

discharge holes

421 and 422 in which the fluid compressed at high pressure is discharged up and down instead of right and left, thereby reducing the size of the hydraulic pump 1 and improving space utilization. Maximized, there is an effect that the bolt fastening safety between the valve block 400 and the left and right hydraulic pumps (100,200) is increased.

3A is a conceptual diagram illustrating the inside of a valve block of a hydraulic pump according to a second exemplary embodiment of the present invention, and FIG. 3B is a conceptual diagram illustrating a kidney hole of a valve block of a hydraulic pump according to a second exemplary embodiment of the present invention.

As shown in FIGS. 3A and 3B, the valve block 400 of the hydraulic pump 1 according to the second embodiment of the present invention includes a fluid discharge passage 450.

The hydraulic pump 1 according to the present invention uses the same reference numerals for convenience of each configuration in the hydraulic pump 1 described in FIGS. 1 and 2, but does not necessarily refer to the same configuration.

The valve block 400 of the hydraulic pump 1 according to the embodiment of the present invention, the fluid compressed in the first hydraulic pump 100 or the second hydraulic pump 200 therein (preferably the compressed fluid) In the second embodiment of the present invention, the outside is the same.

The fluid discharge passage 450 is configured to discharge the fluid compressed by the first hydraulic pump 100 to the outside and the fluid compressed by the second hydraulic pump 200 to the outside. Two fluid discharge passages 450b.

The first fluid discharge passage 450a may include a discharge side first kidney hole 451a connected to the first hydraulic pump 100 and a center line CC that is connected to the outside and bisects the upper and lower sides of the valve block 400. The first discharge hole 453a provided on the upper side and the first connection part 452a connecting the first kidney hole 451a and the first discharge hole 453a may be included.

The discharge-side first kidney hole 451a is a space into which the fluid compressed by the first hydraulic pump 100 flows into the first fluid discharge passage 450a and is formed to have a shape similar to a human kidney. 452a).

The first connection part 452a is continuously formed such that the discharge side first kidney hole 451a and the first discharge hole 453a are connected to each other, and the first connection part in which the curvature direction of the upper curve and the curvature direction of the lower curve are opposite to each other. The first connection part 4452a may include a first connection second part 4522a having the same curvature direction as the upper curve and the lower curve as the curvature direction.

Specifically, the first connection first portion 4451a may be formed symmetrically with respect to the center line BB that bisects the top and bottom of the first connection first portion 4451a and is discharge-side first kid. It is provided between the knee hole 451a and the first connecting second portion 4522a, and may occupy an area of 30% to 40% of the first connecting portion 452a, and the first connecting second portion 4522a may include A first connection part 4451a and a first discharge hole 453a may be provided between the first connection part 4451a and the first discharge hole 453a.

The second fluid discharge passage 450b includes a discharge side second kidney hole 451b connected to the second hydraulic pump 200 and a center line CC connected to the outside and bisecting the upper and lower sides of the valve block 400. The second discharge hole 453b provided below and a second connection part 452b connecting the second kidney hole 451b and the second discharge hole 453b to each other may be included.

The discharge-side second kidney hole 451b is a space into which the fluid compressed in the second hydraulic pump 200 flows into the second fluid discharge passage 450b, and is formed in a shape similar to the shape of a human kidney. 452b).

The second connection part 452b is continuously formed such that the discharge-side second kidney hole 451b and the second discharge hole 453b are connected to each other, and the second connection part in which the curvature direction of the upper curve and the curvature direction of the lower curve are opposite to each other. The first connection portion 4451b and the second curved portion 4522b having the same curvature direction as the upper curve and the lower curve may be included.

In detail, the second connection first portion 4451b may be formed to be symmetrical with respect to the center line BB that bisects the top and bottom, and the discharge side second Kidney hole 451b and the second connection second may be formed. It is provided between the portions 4522b, and may occupy an area of 30% to 40% of the second connecting portion 452b, and the second connecting second portion 4522b is formed of the second connecting first portion 4451b and the first portion. The second discharge holes 453b may be provided between the second discharge holes 453b to connect the second connection first portions 4451b and the second discharge holes 453b.

As such, the fluid discharge flow path 450 is formed by symmetrically forming the fluid discharge flow path 450 formed at the inside of the valve block 400 based on the center line BB at least partially bisecting the top and bottom. ) Can effectively reduce the magnitude of the stress received, the effect of maximizing the durability of the hydraulic pump (1).

Experimental data that can derive this effect will be described in FIG. 6.

Figure 6A is a structural analysis result showing the structural analysis results showing the state of the stress received by the Kidney hole when driving the conventional hydraulic pump, Figure 6B is a Kidney Hall when driving the hydraulic pump according to an embodiment of the present invention The structural analysis result diagram which shows the structural analysis result which shows the state of this received stress.

6A and 6B show that the stress concentration increases in the direction of the arrow in the center of the figure. 6A and 6B, the left side shows a structural analysis result of the discharge-side first kidney hole 451a which is stressed by the fluid discharged from the first hydraulic pump 100, and the right side shows the fluid discharged from the second hydraulic pump 200. This is a structural analysis result of the discharge-side second kidney hole 451b subjected to the stress caused by the stress.

Referring to the left side of FIG. 6A, the stress received by the discharge-side first kidney hole by the first hydraulic pump is 703 MPa in the upper side and 502 MPa in the lower side, but the magnitude of the stress is largely derived. In the embodiment of the present invention, 6B, it can be seen that the stress received by the discharge-side first kidney hole 451a by the first hydraulic pump 100 is 320MPa in the upper side and 333MPa in the lower side, and the magnitude of the stress is significantly reduced. .

6A, the stress received by the discharge side first kidney hole 451a by the second hydraulic pump 200 is 370 MPa in the upper side and 1267 MPa in the lower side, and the magnitude of the stress is very large. Although derived, in the embodiment of the present invention, looking at the right side of FIG. 6B, the stress received by the discharge side first kidney hole 451a by the second hydraulic pump 200 receives 321 MPa in the upper side and 332 MPa in the lower side. You can see that the size is significantly reduced.

That is, when looking at the data shown in FIGS. 6A and 6B, the hydraulic pump 1 according to the embodiment of the present invention has increased durability because the magnitude of the stress applied to the discharge-side first kidney hole 451a is reduced. It is possible to derive the fact that there is an effect of reducing the risk of breakage and improving the driving reliability of the hydraulic pump 1.

As described above, the hydraulic pump 1 according to the present invention is formed in the symmetrical interval from the

Kidney holes

451a and 451b by a predetermined interval, and is formed in a gentle curved interval from the preset interval to the fluid discharge hole. Effectively reducing the size of the stress discharged to the fluid discharge passage 450 has the effect of improving the durability, it is possible to reduce the additional machining after casting has the effect of reducing the cost of the product.

4A is an internal conceptual view showing the interior of a valve block of a conventional hydraulic pump, and FIG. 4B is an internal conceptual view showing the interior of a valve block of a hydraulic pump according to a third embodiment of the present invention.

As shown in FIG. 4B, the valve block 400 of the hydraulic pump 1 according to the third exemplary embodiment of the present invention may include a valve block right side 410, a valve block rear side 420, and a valve block left side ( 430 and a valve block front portion 440, a fluid discharge passage 450, a regulator fluid supply passage 460b, and a sensor fluid supply passage 470.

The valve block right surface portion 410, the valve block rear surface portion 420, the valve block left surface portion 430, and the valve block front surface portion 440 of the valve block 400 according to the present invention are hydraulic pressures described with reference to FIGS. 1 to 3. Although the same reference numerals are used for the convenience of the respective configurations in the pump 1, they do not necessarily refer to the same configuration.

The fluid discharge passage 450 is provided inside the valve block 400 and is formed to have a curvature so that the fluid discharged from the first hydraulic pump 100 or the second hydraulic pump 200 is external (preferably A working device using a compressed fluid; in the second embodiment of the present invention, the outside is the same). The fluid discharge passage 450 may be referred to as a fluid main discharge passage, and the fluid main discharge passage is described as the fluid discharge passage 450 in this embodiment.

The fluid discharge passage 450 includes

Kidney holes

451a and 451b connected to the first hydraulic pump 100 or the second hydraulic pump 200,

discharge holes

453a and 453b connected to the outside, and Kidney hole 451a. , 451b and the

discharge holes

453a and 453b may include connecting

portions

452a and 452b that form a curved line.

The fluid discharge passage 450 may have one branch point for branching. Specifically, the fluid discharge passage 450 may be a branch of the sensor fluid supply passage 470 to be described later, the center line that bisects the top and bottom of the Kidney holes (451a, 451b) of the fluid discharge passage 450 Can be connected to the lower side as a reference.

The magnitude of the stress generated at the branching point when at least a portion of the fluid branches in the straight portion is much smaller than the magnitude of stress occurring at the branching point when at least a portion of the fluid branches in the curved portion.

Therefore, in the exemplary embodiment of the present invention, the first hydraulic pump 100 or the second hydraulic pump 200 is diverged so as to branch only under the

kidney holes

451a and 451b and not the curved portion of the fluid discharge passage 450. The amount of stress generated in the fluid discharge passage 450 may be reduced by the high pressure fluid discharged from the. Experiments for such an effect are shown in FIGS. 6A and 6B, the contents of which have been described in the second embodiment of the present invention.

Specifically, referring to FIG. 4A, it can be seen that the regulator fluid supply passage 460a to be described later is further branched from the curved portion of the fluid discharge passage 450. Therefore, in the related art, a branching point is generated at a curved portion of the fluid discharge channel 450, and thus, a magnitude of the stress applied to the fluid discharge channel 450 is very large, and thus durability is weakened, thereby deteriorating driving reliability of the hydraulic pump 1. there was.

Accordingly, in the embodiment of the present invention, the sensor fluid supply passage 470 branches only below the

kidney holes

451a and 451b, not the curved portion of the fluid discharge passage 450, and the regulator fluid supply passage 460b. Is branched from the sensor fluid supply passage 470 instead of the fluid discharge passage 450, the fluid discharge passage 450 by the high pressure fluid discharged from the first hydraulic pump 100 or the second hydraulic pump 200 The amount of stress generated in the can be reduced, thereby improving the durability of the hydraulic pump (1) and there is an effect that the driving reliability is maximized.

The regulator fluid supply passage 460b is branched from the sensor fluid supply passage 470, which will be described later, preferably branched from a straight section of the sensor fluid supply passage 470, and flows through the sensor fluid supply passage 470. At least a portion of the can be discharged to a second device (not shown) using the compressed fluid. Here, the second device may be a regulator for adjusting the inclination angles of the

swash plates

111 and 211 for adjusting the discharge flow rate of the first hydraulic pump 100 or the second hydraulic pump 200. The regulator fluid supply passage 460b may be referred to as a fluid second secondary discharge passage, and the fluid second secondary discharge passage is described as a regulator fluid supply passage 460b in this embodiment.

The regulator fluid supply passage 460a in the embodiment according to FIG. 4A is branched from the fluid discharge passage 450 to directly supply the high pressure fluid from the first hydraulic pump 100 or the second hydraulic pump 200. The concentration of stress was very large, and branched in a curved section rather than a straight section, and the concentration of stress intensified according to the branch position was intensified.

Accordingly, in the third embodiment of the present invention, the regulator fluid supply passage 460b is branched from the sensor fluid supply passage 470 so that the high pressure fluid is directly supplied from the first hydraulic pump 100 or the second hydraulic pump 200. By dispersing the stress concentration by branching in a straight section of the sensor fluid supply passage 470 to reduce the concentration of stress, it is effective in enhancing durability and improving driving reliability.

The sensor fluid supply passage 470 has a straight line at least partially branched from the fluid discharge passage 450 to compress the fluid compressed in the first hydraulic pump 100 or the second hydraulic pump 200. Can be discharged to a first device (not shown) that uses. Here, the first device may be a sensor that measures the pressure of the fluid compressed by the first hydraulic pump 100 or the second hydraulic pump 200. The sensor fluid supply passage 470 may be referred to as a fluid first subdischarge passage, and the fluid first subdischarge passage is described as the sensor fluid supply passage 470 in this embodiment.

The sensor fluid supply passage 470 is branched from the lower side on the basis of a center line that bisects the top and bottom of the

Kidney holes

451a and 451b of the fluid discharge passage 450, so that the first hydraulic pump 100 or the second The fluid compressed in the hydraulic pump 200 may be supplied to the sensor.

As described above, the hydraulic pump 1 according to the present invention arranges the position of the flow path 460b supplied to the regulator so as to branch on the flow path 470 supplied to the sensor, and thus the branch point (flow path) on the fluid discharge flow path 450. The intersection point) is reduced to one, and the durability is improved, and the stress applied to the branch point by branching on a straight flow path of the flow path 470 supplied to the sensor is smaller, thereby maximizing durability.

5A is a conceptual diagram illustrating a connection state of a fluid main discharge passage and a sensor fluid supply passage of a valve block of a hydraulic pump according to a fourth embodiment of the present invention, and FIG. 5B is a hydraulic pump according to a fourth embodiment of the present invention. This is a conceptual diagram showing the connection state between the sensor fluid supply channel and the regulator fluid supply channel of the valve block.

As shown in FIGS. 5A and 5B, the valve block 400 of the hydraulic pump 1 according to the fourth embodiment of the present invention includes a fluid discharge passage 450, a regulator fluid supply passage 460b, and a sensor fluid. Supply passage 470 is included.

Although the hydraulic pump 1 which concerns on this invention uses the same code | symbol for each structure and convenience in the hydraulic pump 1 demonstrated in FIGS. 1-4, it does not necessarily refer to the same structure.

In the fluid discharge passage 450, the fluid compressed in the first hydraulic pump 100 or the second hydraulic pump 200 flows. In detail, the fluid discharge passage 450 may include

Kidney holes

discharge holes

453a and 453b connected to the outside, and a kid. It may include a connecting portion (452a, 452b) to form a curve connecting the knee holes (451a, 451b) and the discharge holes (453a, 453b).

Conventionally, a step is formed at the point where the

kidney holes

451a and 451b and the

connection parts

452a and 452b are connected to form an arbitrary angle. In this case, the stress caused by the high-pressure fluid is concentrated at the connection point due to the step formed at the point connecting the

kidney holes

451a and 451b and the

connection parts

452a and 452b.

Accordingly, in the embodiment of the present invention, the point CC connecting the

kidney holes

451a and 451b and the

connection parts

452a and 452b may be configured to have a curvature, that is, not to form a step. Therefore, at the point CC connecting the

kidney holes

451a and 451b and the

connection parts

452a and 452b, stress due to the high pressure fluid is not concentrated, thereby improving durability and maximizing driving reliability of the hydraulic pump 1. It is effective.

In addition, the point (CC) for connecting the Kidney holes (451a, 451b) and the connecting portion (452a, 452b) is configured to have a curvature to form a single frame during the casting production has the effect of reducing the additional machining. . This further reduces the production cost.

The fluid discharge passage 450 is provided inside the valve block 400 and is formed to have a curvature so that the fluid discharged from the first hydraulic pump 100 or the second hydraulic pump 200 is external (preferably A working device using a compressed fluid; in the fourth embodiment of the present invention, the outside is the same). In the fluid discharge path 450, the connecting

parts

452a and 452b and the

discharge holes

453a and 453b may be second flow paths having only curved sections.

The portion having the curvature, that is, the curved section, in the fluid discharge passage 450 may be formed to have no branch point. Specifically, the fluid discharge passage 450 is branched only from the lower side of the

kidney holes

451a and 451b, not the curved portion, so that the fluid discharge passage 450 is discharged from the first hydraulic pump 100 or the second hydraulic pump 200. The amount of stress generated in the fluid discharge passage 450 by the fluid may be reduced. Experiments for such an effect are shown in FIGS. 6A and 6B, the contents of which have been described in the second embodiment of the present invention.

swash plates

111 and 211 for adjusting the discharge flow rate of the first hydraulic pump 100 or the second hydraulic pump 200.

The point connecting the regulator fluid supply passage 460b and the sensor fluid supply passage 470, that is, the branch point DD branched from a straight section of the sensor fluid supply passage 470, has a curvature, that is, a step It may be configured not to be formed. Therefore, at the point DD connecting the regulator fluid supply passage 460b and the sensor fluid supply passage 470, stress due to the high pressure fluid is not concentrated, so that the durability is improved and the driving reliability of the hydraulic pump 1 is improved. There is an effect that is maximized.

In addition, the branch point (DD) branching in a straight section of the sensor fluid supply passage 470 is configured to have a curvature to form a single frame during the casting production has the effect of reducing the additional machining. This further reduces the production cost.

The regulator fluid supply passage 460b may be a first passage having at least some passages having a straight section and may have a branch point connected to the sensor fluid supply passage 470.

The sensor fluid supply passage 470 has a straight line at least partially branched from the fluid discharge passage 450 to compress the fluid compressed in the first hydraulic pump 100 or the second hydraulic pump 200. Can be discharged to a first device (not shown) that uses. Here, the first device may be a sensor that measures the pressure of the fluid compressed by the first hydraulic pump 100 or the second hydraulic pump 200.

Kidney holes

In this case, the point EE connected to the sensory supply passage 470 and the

kidney holes

451a and 451b of the fluid discharge passage 450 may be configured to have a curvature, that is, not to form a step. Therefore, at the point EE connected between the sensor fluid supply passage 470 and the

kidney holes

451a and 451b of the fluid discharge passage 450, stress caused by the high pressure fluid is not concentrated and the durability is improved, and the hydraulic pump is improved. The driving reliability of (1) is maximized.

In addition, the point (EE) that is connected to the Kidney holes (451a, 451b) of the sensor fluid supply passage 470 and the fluid discharge passage 450 is configured to have a curvature to form a single frame during the casting production additional machine There is an effect to reduce the processing. This further reduces the production cost.

The sensor fluid supply passage 470 may be a first passage having at least some passages having a straight section, and may have a branch point connected to the regulator fluid supply passage 460b.

As described above, the hydraulic pump 1 according to the present invention includes a connection point CC of the

flow paths

450, 460b and 470 through which the fluid in the hydraulic pump 1 flows, or the

kidney holes

451a and 451b and the

connection parts

452a and 452b. ), The connecting point EE on the straight channel and the straight channel or the curved channel having at least part of the straight section and the connecting point DD on the straight channel to form a curvature so that the stress at the connecting points CC, DD and EE This phenomenon can be prevented from being concentrated, thereby improving durability, and by forming the casting shape with curvature during fabrication, it is possible to reduce additional machining, thereby reducing the cost of the product.

Although the present invention has been described in detail through specific examples, it is intended to describe the present invention in detail, and the present invention is not limited thereto, and should be understood by those skilled in the art within the technical spirit of the present invention. It is obvious that the modifications and improvements are possible.

All simple modifications and variations of the present invention fall within the scope of the present invention, and the specific scope of protection of the present invention will be apparent from the appended claims.

Claims

A first hydraulic pump provided on one side to compress the fluid;

A second hydraulic pump provided on the other side to compress the fluid; And

It includes a valve block provided between the first hydraulic pump and the second hydraulic pump,

The valve block is,

It has a fluid discharge passage for discharging the fluid compressed by the first hydraulic pump or the second hydraulic pump to the outside,

The fluid discharge flow path,

A discharge-side kidney hole connected to the first hydraulic pump or the second hydraulic pump;

A discharge hole connected to the outside; And

A connection part connecting the discharge side kidney hole and the discharge hole;

The connecting portion,

A hydraulic pump, characterized in that at least a portion is formed up and down symmetrically with respect to the center line dividing the upper and lower parts.
The method of claim 1, wherein the connection portion,

A first connection part connected to the discharge-side kidney hole and having an upper curvature direction and a lower curvature direction opposite to each other, the first and second symmetrical parts being formed symmetrically with respect to a center line dividing the upper and lower parts; And

And a connecting second part which connects the connecting first part and the discharge hole and has the same curvature direction of the upper curve and the curvature direction of the lower curve.
The method of claim 2, wherein the first connection portion,

Hydraulic pump, characterized in that occupies 30% to 40% area of the connection.
The method of claim 1, wherein the fluid discharge flow path,

A first fluid discharge passage configured to discharge the fluid compressed by the first hydraulic pump to the outside; And

A second fluid discharge passage configured to discharge the fluid compressed by the second hydraulic pump to the outside;

The first fluid discharge flow path,

A discharge side first kidney hole connected to the first hydraulic pump;

A first discharge hole connected to the outside and provided at an upper side of the valve block at a center line dividing the upper and lower sides of the valve block; And

A first connection part connecting the discharge side first kidney hole and the first discharge hole,

The second fluid discharge passage,

A discharge side second kidney hole connected to the second hydraulic pump;

A second discharge hole connected to the outside and provided at a lower side with respect to a center line bisecting the upper and lower sides of the valve block; And

And a second connection part connecting the discharge side second kidney hole and the second discharge hole.
The method of claim 4, wherein the first connecting portion,

A first connection first part connected to the discharge side first kidney hole and having an upper curvature direction and a lower curvature direction opposite to each other, the first connecting part being symmetrical with respect to a center line dividing the upper and lower parts; And

A first connection second part connecting the first connection first part and the first discharge hole and having the same curvature direction of the upper curve and the curvature direction of the lower curve;

The second connection portion,

A second connection first part connected to the discharge second second knee hole and formed to be opposite to the curvature direction of the upper curve and the curvature direction of the lower curve, the second connecting first part being symmetrical with respect to the center line dividing the upper and lower parts; And

And a second connecting second part connecting the second connecting first part and the second discharge hole and having the same curvature direction of the upper curve and the curvature direction of the lower curve.
The method of claim 5, wherein the first fluid discharge passage and the second fluid discharge passage,

Hydraulic pump, characterized in that formed in a point symmetrical with respect to the center point that is bisected between the first discharge hole and the second discharge hole.
The method of claim 1, wherein the valve block,

It includes a fluid inlet for supplying a fluid to the first hydraulic pump or the second hydraulic pump,

The fluid discharge portion,

A hydraulic pump located opposite the fluid inlet.