WO2014010529A1

WO2014010529A1 - Hydraulic rotary machine

Info

Publication number: WO2014010529A1
Application number: PCT/JP2013/068494
Authority: WO
Inventors: 愛智藪内; 新留　隆志; 隆松村
Original assignee: 日立建機株式会社
Priority date: 2012-07-10
Filing date: 2013-07-05
Publication date: 2014-01-16

Abstract

The rotary shaft (5, 42, 63, 84) of a hydraulic pump (1, 41, 61, 81, 85) that is this hydraulic rotary machine is coupled to a drive source coupling (20, 44, 92) using a spline coupler (23, 47). The rotary shaft (5, 42, 63, 84) is provided with: an oil supply pathway (24, 48, 77) that supplies hydraulic oil inside a casing (2, 62, 82) as lubricating oil to the spline coupler (23, 47); and an oil return pathway (25, 49, 78) that recovers and returns into the casing (2, 62, 82) the lubricating oil that had been supplied to the spline coupler (23, 47) by the oil supply pathway (24, 48, 77). Between the coupling (20, 44, 92) and the rotary shaft (5, 42, 63, 84) is provided a seal member (28, 52) that prevents lubricating oil supplied to the spline coupler (23, 47) from leaking to the outside.

Description

Hydraulic rotating machine

The present invention relates to a hydraulic rotating machine used as a hydraulic pump or a hydraulic motor for civil engineering / building machines and other general machines, for example.

Generally, a hydraulic rotating machine is used as a hydraulic pump or a hydraulic motor in construction machines represented by a hydraulic excavator and other general machines. This type of prior art hydraulic rotating machine has a configuration in which, for example, when used as a hydraulic pump, a rotating shaft rotatably provided in a pump casing is connected to an output shaft on the drive source side by a spline coupling portion. (Patent Document 1).

The drive source is an electric motor, and a motor case of the electric motor is rotatably provided with an output shaft of the motor, and the output shaft extends to an end surface of the motor case. The output shaft is provided with a bottomed hole extending in the axial direction, and a coupling for transmitting the rotation of the output shaft is formed. A female spline is formed on the inner peripheral surface of the bottomed hole constituting the coupling, and a male spline that meshes with the female spline is formed on the outer peripheral surface of the rotating shaft. The end surface of the motor case and the end surface of the pump casing are joined in a state of abutting each other. Thereby, the end surface of the pump casing is attached in a sealed state to the end surface of the motor case, and the hydraulic oil in the hydraulic pump is prevented from leaking to the outside.

JP 2010-180911 A

By the way, in the above-described conventional technology, the rotation shaft of the hydraulic pump and the output shaft of the electric motor are connected by a spline coupling portion, and the rotation of the output shaft is transmitted to the rotation shaft. The pump casing is provided with an oil guide path for guiding hydraulic oil in the hydraulic pump to the spline coupling portion as lubricating oil. Further, a seal member is provided between the motor case and the outer periphery of the output shaft so that the hydraulic oil guided to the spline coupling portion does not leak.

That is, in the prior art, in order to abut the motor case with the pump casing, it is necessary to extend the motor case in the axial direction to a position where it abuts with the pump casing. In addition, the seal member is provided between the inner peripheral side of the motor case and the output shaft. For this reason, the shape of the motor case becomes complicated and the entire apparatus becomes large. Moreover, the seal member is provided on the outer peripheral side of the output shaft on which the female spline is formed. For this reason, the sealing member needs to use a sealing member having a diameter larger than the radial dimension of the female spline, which increases the cost.

The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to maintain a spline coupling portion in a lubricated state between a coupling that performs rotation transmission and a rotation shaft, and An object of the present invention is to provide a hydraulic rotating machine capable of preventing leakage of hydraulic oil without increasing its size.

(1). In order to solve the above-described problems, the present invention provides a cylindrical casing, a rotary shaft rotatably provided on the casing via a bearing, and the casing provided in the casing so as to rotate integrally with the rotary shaft. A cylinder block having a plurality of cylinder holes spaced in the circumferential direction and extending in the axial direction, a plurality of pistons inserted into the cylinder holes of the cylinder block so as to be able to reciprocate from one side in the axial direction, and the cylinder A valve plate provided between the other side in the axial direction of the block and the casing and provided with an inlet port and an outlet port for hydraulic oil provided in the casing and intermittently communicating with the cylinder holes; and the rotary shaft A driving source that rotates the rotating shaft, or a rotating body that is driven to rotate by the rotating shaft, and a coupling that connects the rotating shaft to the rotating shaft and the coupling. Applied to the hydraulic rotary machine comprising linked using a line coupling unit.

A feature of the configuration adopted by the present invention is that an oil supply passage for supplying hydraulic oil in the casing as lubricating oil to the spline coupling portion formed between the rotating shaft and the coupling is provided on the rotating shaft, and the oil supply A lubricating oil supplied to the spline coupling portion is provided between the coupling and the rotary shaft between the coupling and the rotary shaft. In other words, a seal member is provided to prevent leakage of the liquid to the outside.

With this configuration, the oil supply passage provided in the rotating shaft can supply the working oil in the casing as a lubricating oil to the spline joint between the coupling and the rotating shaft. The return oil path provided in the rotating shaft can collect the lubricating oil supplied to the spline coupling portion and return it to the casing. Furthermore, the seal member provided between the coupling and the rotating shaft can prevent the lubricating oil supplied to the spline coupling portion from leaking to the outside.

For this reason, it can be set as the structure which covers a spline coupling | bond part from the outside by either one of a coupling and a rotating shaft. In addition, the seal member provided inside the one member can prevent the lubricating oil from leaking to the outside of the one member. That is, it is not necessary to provide a seal member outside the one member. As a result, the structure of the entire apparatus can be simplified and downsizing can be achieved.

(2). According to the present invention, between the coupling and the rotary shaft, the oil guide is arranged on one side in the axial direction with the spline coupling portion interposed therebetween, and guides the lubricating oil supplied from the oil supply passage to the spline coupling portion. A space and an oil recovery space that is disposed on the opposite side of the oil guiding space across the spline coupling portion and that guides the lubricating oil discharged from the spline coupling portion to the return oil path, and the seal The member is configured to seal the oil recovery space from the outside.

With this configuration, an oil guiding space and an oil recovery space can be formed on both sides in the axial direction between the coupling and the rotating shaft with the spline coupling portion interposed therebetween. Lubricating oil can be supplied to the spline coupling portion while the lubricating oil is temporarily stored. Further, the lubricating oil discharged from the spline coupling portion is guided from the oil recovery space to the return oil passage. Thereby, lubricating oil can be returned in a casing. The seal member can prevent the lubricating oil in the oil recovery space from leaking to the outside.

(3). According to the present invention, the return oil passage opens in the casing at a position near the bearing so as to guide the recovered lubricating oil to the bearing that rotatably supports the rotating shaft in the casing. It is said. If comprised in this way, when returning the lubricating oil collect | recovered by the return oil path side among the lubricating oil supplied to the spline coupling | bond part by the oil supply path, this rotating shaft can rotate a rotating shaft within a casing. The bearings can be supplied to the bearings, and the bearings can be kept in a lubricated state.

(4). According to the present invention, the oil supply passage is configured to supply hydraulic oil leaked from one or both of the inflow port and the outflow port of the valve plate to the spline coupling portion. As a result, the hydraulic oil leaked into the cylinder block from one or both of the inflow port and the outflow port of the valve plate can be guided into the oil supply passage in the rotary shaft, and the lubricating oil can be splined through the oil supply passage. Can be supplied to.

(5). According to the present invention, the oil supply passage is configured to supply hydraulic oil leaked from the sliding surface between the cylinder block and the valve plate to the spline coupling portion. As a result, the hydraulic oil leaked into the cylinder block from the sliding surface between the cylinder block and the valve plate can be guided into the oil supply passage in the rotary shaft, and the lubricating oil is supplied to the spline joint through the oil supply passage. Can do.

(6). According to the present invention, the spline coupling portion is provided on the outer peripheral side of the other member so as to mesh with the female spline provided on the inner peripheral side of one member of the coupling and the rotating shaft. The one member is formed as a covered cylindrical body or a bottomed cylindrical body that is closed on one side in the axial direction and opened on the other side across the female spline, and the sealing member The opening side of the one member is sealed.

According to the above configuration, the spline coupling portion can be configured by the female spline provided on one member of the coupling and the rotating shaft and the male spline provided on the other member. The one member can be formed as a covered cylindrical body or a bottomed cylindrical body in which one side in the axial direction is closed and the other side is opened across the female spline. The sealing member can prevent the lubricating oil from leaking from the inside of one member to the outside by sealing the opening side of the one member.

(7). According to the present invention, the spline coupling portion includes a female spline provided on the inner peripheral side of the coupling and a male spline provided on the outer peripheral side of the rotating shaft so as to mesh with the female spline. The coupling is formed as a covered cylindrical body that is closed on one side in the axial direction and opened on the other side with the female spline interposed therebetween, and the sealing member is configured to seal the opening side of the coupling.

(8). According to the present invention, the spline coupling portion includes a female spline provided on the inner peripheral side of the rotating shaft and a male spline provided on the outer peripheral side of the coupling so as to mesh with the female spline. The rotating shaft is formed as a bottomed cylindrical body that is open on one side in the axial direction and closed on the other side across the female spline, and the sealing member seals the opening side of the rotating shaft. .

1 is a longitudinal sectional view showing an oblique axis hydraulic pump according to a first embodiment of the present invention. FIG. 2 is an enlarged cross-sectional view showing a main part of a spline coupling portion between a rotating shaft and an engine-side hub in FIG. 1. It is a disassembled perspective view which shows the rotating shaft and engine side hub in FIG. It is a longitudinal cross-sectional view which shows the oblique axis type hydraulic pump by 2nd Embodiment. FIG. 5 is an enlarged cross-sectional view showing a main part of a spline coupling portion between a rotating shaft and an engine-side hub in FIG. 4. It is a disassembled perspective view which shows the rotating shaft and engine side hub in FIG. It is a longitudinal cross-sectional view which shows the swash plate type hydraulic pump by 3rd Embodiment. It is a longitudinal cross-sectional view which shows the case where the oblique-axis type hydraulic pump by 4th Embodiment is used as a double pump.

Hereinafter, a case where the hydraulic rotating machine according to the embodiment of the present invention is applied to a variable displacement hydraulic pump will be described as an example, and will be described in detail with reference to the accompanying drawings.

1 to 3 show a first embodiment of a hydraulic rotating machine according to the present invention. The hydraulic rotating machine according to the first embodiment is applied to a variable displacement oblique shaft type hydraulic pump.

In the figure, reference numeral 1 denotes a hydraulic pump composed of a variable displacement oblique-shaft hydraulic rotating machine. The hydraulic pump 1 has a cylindrical casing 2. The casing 2 includes a casing body 3 formed as a stepped cylindrical body and a head casing 4 described later. In the casing body 3, a rotating shaft 5 and a cylinder block 7 described later are provided so as to rotate together.

As shown in FIG. 1, the casing body 3 has a mounting flange 3 A formed in a tapered shape on one side in the axial direction, and a rotating shaft described later is provided on the inner peripheral side of the mounting flange 3 A. A shaft insertion hole 3B on one side through which 5 is inserted is provided. The other axial side of the casing body 3 is a head side end 3C to which the head casing 4 is attached in an abutting state. A cylinder block 7 and a valve plate 13, which will be described later, are accommodated inside the head side end portion 3C so as to be tiltable (movable).

The head casing 4 constitutes a part of the casing 2. The head casing 4 is fixed to the head side end 3C so as to close the head side end 3C of the casing body 3. The head casing 4 is formed with a concavely curved tilt support surface 4A that supports a later-described valve plate 13 so as to be tiltable. Inside the head casing 4, a servo piston 16 of a tilting mechanism 14 described later is provided.

Here, the head casing 4 is formed with a pair of supply / discharge passages (both not shown). Among these supply and discharge passages, the low pressure side supply and discharge passages serve as suction passages for sucking hydraulic oil in a tank (not shown), and the high pressure side supply and discharge passages are discharges for discharging pressure oil as will be described later. It constitutes a passage.

5 is a rotating shaft provided in the casing body 3, and the rotating shaft 5 is rotatably supported in the casing body 3 via a plurality of bearings 6. One end side of the rotating shaft 5 protrudes outside the casing body 3 from the shaft insertion hole 3B. On the other hand, a disk-shaped drive disk 5A is integrally provided on the other end side of the rotating shaft 5. A center shaft 9 (described later) and a plurality of connecting rods 11 are swingably connected to the drive disk 5A. Here, one end side of the rotating shaft 5 is a protruding shaft portion 5B that protrudes outside the casing body 3 from the shaft insertion hole 3B. A male spline 23A of a spline coupling portion 23 described later is formed on the outer peripheral side of the protruding shaft portion 5B.

The cylinder block 7 is rotatably provided in the casing 2. The cylinder block 7 is connected to the drive disk 5A via a center shaft 9, pistons 10 and connecting rods 11 described later, and rotates integrally with the rotary shaft 5. Here, the cylinder block 7 is formed as a circular rotating body, and a center hole 7A into which a center shaft 9 described later is inserted is formed at the axial center position. The cylinder block 7 has a plurality of cylinder holes (usually odd numbers, for example, 5, 7, or 9) that are spaced apart from each other in the circumferential direction around the center hole 7A and extend in the axial direction. 8 is drilled.

The center shaft 9 is used for centering the cylinder block 7. The center shaft 9 extends through the center hole 7A of the cylinder block 7 in the axial direction. One end side of the center shaft 9 is connected to the center side of the drive disk 5A so as to be tiltable, and the other end side is connected to a valve plate 13 described later. An oil guide passage 9 A extending in the axial direction is formed at the axial center position of the center shaft 9. The oil guide passage 9A guides hydraulic oil (hereinafter referred to as oil liquid) in the casing 2 toward an oil supply passage 24 described later.

Here, a plurality of radial holes 9 B are provided on the other end side of the center shaft 9. These radial holes 9 B form guide holes that allow the oil leaked into the center hole 7 A of the cylinder block 7 to flow into the oil guide passage 9 A of the center shaft 9. That is, in the center hole 7 A of the cylinder block 7, oil liquid in a relatively high pressure state leaks from the sliding surface between the cylinder block 7 and the valve plate 13. The leaked oil is in a higher pressure state than the oil liquid stored in the casing 2 outside the cylinder block 7. The leaked oil having a high pressure is guided from the center hole 7A into the oil guide passage 9A through the radial holes 9B of the center shaft 9.

The plurality of pistons 10 are inserted into the cylinder holes 8 of the cylinder block 7 so as to be reciprocable from one side in the axial direction. These pistons 10 are slidably inserted into the cylinder holes 8 of the cylinder block 7. When the cylinder block 7 is rotationally driven together with the rotary shaft 5, each piston 10 reciprocates in each cylinder hole 8, and repeats the suction stroke and the discharge stroke. A connecting rod 11 is attached to each piston 10. These connecting rods 11 are supported on the drive disk 5 A of the rotary shaft 5 so that the tip side (one side in the axial direction) can swing.

Each connecting rod 11 transmits a rotational force to the cylinder block 7 as the rotating shaft 5 (drive disk 5A) rotates, and reciprocates each piston 10 within each cylinder hole 8. As a result, each piston 10 oils into the cylinder hole 8 from the valve plate 13 side while sliding in the cylinder hole 8 from the top dead center to the bottom dead center (that is, while the cylinder block 7 rotates halfway). Perform an inhalation stroke to suck in the liquid. While each piston 10 slides in the cylinder hole 8 from the bottom dead center to the top dead center (that is, while the cylinder block 7 performs the remaining half rotation), the oil liquid is moved from the cylinder hole 8 to the valve plate 13 side. This is a discharge stroke for discharging the water.

The spring 12 is provided between the center hole 7A of the cylinder block 7 and the center shaft 9. The spring 12 is attached in the center hole 7A of the cylinder block 7 while being wound around the outer peripheral side of the center shaft 9, and constantly urges the cylinder block 7 toward the valve plate 13. As a result, the cylinder block 7 rotates integrally with the rotary shaft 5 while sliding with respect to the valve plate 13, and continues to rotate relative to the valve plate 13.

The valve plate 13 is provided between the head casing 4 of the casing 2 and the other side surface of the cylinder block 7. The valve plate 13 is supported on the tilt support surface 4A of the head casing 4 so as to be tiltable. The valve plate 13 is driven to tilt along the tilt support surface 4A by a tilt mechanism 14 described later when the pump capacity (discharge capacity) of the hydraulic pump 1 is changed. On one side surface of the valve plate 13, the other side surface of the cylinder block 7 is slidably disposed. The cylinder block 7 rotates while making sliding contact with the valve plate 13. Thereby, the suction | inhalation and discharge of the oil liquid with respect to each cylinder hole 8 are performed as follows.

That is, the valve plate 13 is formed with a pair of inflow and outflow ports (not shown) having an eyebrow shape extending in the circumferential direction. These inflow port and outflow port communicate with the pair of supply / exhaust passages formed in the head casing 4. The inflow port and the outflow port of the valve plate 13 communicate with each cylinder hole 8 intermittently as the cylinder block 7 rotates. In the intake stroke of the piston 10, oil is sucked into each cylinder hole 8 from the inflow port of the valve plate 13, and in the discharge stroke, oil is discharged from each cylinder hole 8 toward the outflow port of the valve plate 13. The

At this time, a part of the oil leaks out of the valve plate 13 from one or both of the inflow port and the outflow port of the valve plate 13. This leaked oil flows from the sliding surface of the valve plate 13 and the cylinder block 7 into the oil guide passage 9A through the center hole 7A of the cylinder block 7 and the radial hole 9B of the center shaft 9. A through hole 13 A is formed in the center of the valve plate 13. The other end of the center shaft 9 and a swing pin 17 described later are inserted into the through hole 13A from both sides.

The sector-type tilt mechanism 14 tilts and drives the valve plate 13 along the tilt support surface 4A. This tilting mechanism 14 is slidably fitted in a cylinder chamber 15 formed in the head casing 4 and in the cylinder chamber 15, and two hydraulic chambers 15 A and 15 B are provided on both axial sides of the cylinder chamber 15. And a swing pin that is fitted in an intermediate portion of the servo piston 16 in a direction orthogonal to the axis thereof and is inserted into the through hole 13A of the valve plate 13 so as to be swingable. 17.

The servo piston 16 of the tilting mechanism 14 is slidably displaced in the cylinder chamber 15 by supplying and discharging pressure oil into the

hydraulic chambers

15A and 15B from the outside, and the valve plate 13 is moved via the swing pin 17. To drive. For this reason, the valve plate 13 is tilted along the tilt support surface 4A of the head casing 4, and the tilt angles (not shown) of the cylinder block 7 and the valve plate 13 with respect to the rotating shaft 5 are changed. When the tilt angle of the cylinder block 7 changes, the stroke amount of each piston 10 reciprocating in each cylinder hole 8 is variably adjusted according to this tilt angle. As a result, the discharge amount (capacity) of the pressure oil by the hydraulic pump 1 is variably controlled.

Next, the configuration on the drive source side that rotationally drives the rotary shaft 5 of the hydraulic pump 1 will be described. In this case, a diesel engine is generally used as the drive source, but is not limited to this, and an electric motor may be used as the drive source.

The cylindrical housing 18 constitutes an outer shell of an engine (not shown) that is a drive source of the hydraulic pump 1. An attachment flange 3A of the casing body 3 is detachably fastened to the housing 18 using a plurality of bolts 18A. As a result, the casing 2 of the hydraulic pump 1 is supported in a fixed state on the housing 18 of the engine. A flywheel 19 that is rotationally driven integrally with a crankshaft (not shown) of the engine is provided inside the housing 18. The rotation of the flywheel 19 is transmitted to the rotating shaft 5 of the hydraulic pump 1 through a coupling 20 described later.

20 is a coupling for transmitting the rotation of the engine to the rotating shaft 5 of the hydraulic pump 1, and the coupling 20 constitutes a rotating member on the drive source side. The coupling 20 includes an annular plate 21 made of an annular flat plate material and a hub 22 described later. Here, as shown in FIG. 1, the outer peripheral side of the annular plate 21 of the coupling 20 is detachably fixed to the flywheel 19 using a plurality of fasteners 21 A (for example, bolts). A hub 22 described later is detachably fixed to the inner peripheral side of the annular plate 21 using a plurality of fasteners 21B (for example, rivets or bolts).

The hub 22 constitutes a part of the coupling 20, and the hub 22 is formed as a covered cylindrical body. The hub 22 includes a cylindrical portion 22A that extends in the axial direction, a lid portion 22B that closes one axial direction of the cylindrical portion 22A, and an annular flange that is provided on the outer peripheral side of the cylindrical portion 22A and extends radially outward. 22C. The hub 22 may have a configuration in which a lid portion 22B is integrally formed with the cylindrical portion 22A. On the other hand, the hub 22 may form the cylindrical portion 22A and the lid portion 22B by separate members. In the case of forming with a separate member, the lid portion 22B may be fixed to the cylindrical portion 22A using welding means.

As shown in FIGS. 2 and 3, a plurality of fastener insertion holes 22 D are formed in the flange portion 22 C of the hub 22, and the flange portion 22 C is connected to each fastener inserted through these fastener insertion holes 22 D. It is fastened to the inner peripheral side of the annular plate 21 by 21B. Accordingly, the hub 22 of the coupling 20 is connected to the flywheel 19 via the annular plate 21 and rotates integrally with the flywheel 19. The other side in the axial direction of the cylindrical portion 22 A serves as an opening end 22 E, and one side (projecting shaft portion 5 B) of the rotating shaft 5 is inserted into the cylindrical portion 22 A of the hub 22 from the opening end 22 E side. In addition, the coupling 20 may be configured such that the annular plate 21 and the hub 22 are formed as an integrated body, and in this case, the fastener 21B can be omitted.

23 is a spline connecting portion for connecting the protruding shaft portion 5B of the rotating shaft 5 to the hub 22. As shown in FIGS. 2 and 3, the spline coupling portion 23 includes a male spline 23A provided on the outer peripheral side of the protruding shaft portion 5B of the rotating shaft 5, and a cylinder of the hub 22 so as to mesh with the male spline 23A. It is comprised by the female spline 23B provided in the inner peripheral side of the part 22A.

In the hub 22, a later-described oil guiding space 29 is formed on one side in the axial direction with the spline coupling portion 23 interposed therebetween, and a later-described oil collecting space 30 is formed on the other side in the axial direction. Lubricating oil is supplied to the spline coupling portion 23 from the oil guiding space 29 side. This lubricating oil keeps the meshing surfaces of the male spline 23A and the female spline 23B in a lubricated state while flowing toward the oil recovery space 30.

The oil supply path 24 is provided at the axial center position of the rotary shaft 5. The oil supply passage 24 is formed as an axial passage extending in the axial direction of the rotary shaft 5. One side of the oil supply passage 24 is open to the end surface of the protruding shaft portion 5B of the rotary shaft 5 so as to communicate with an oil guide space 29 described later. The other side of the oil supply path 24 communicates with the oil guide path 9A of the center shaft 9 on the center side of the drive disk 5A. Thereby, the oil supply path 24 distributes the oil liquid guided into the oil guide path 9 A toward the oil guide space 29.

A plurality of return oil passages 25 are provided on the rotary shaft 5. These return oil passages 25 are a plurality of (for example, two) passage holes 25A formed so as to extend in the axial direction at positions spaced from the oil supply passage 24 in the radial direction of the rotary shaft 5, a male spline 23A, and a later-described A constricted portion 25B formed on the outer periphery of the projecting shaft portion 5B of the rotating shaft 5 located between the seal groove 27 and the projecting shaft of the rotating shaft 5 so that the constricted portion 25B communicates with each passage hole 25A. A radial hole 25C formed extending in the radial direction of the portion 5B, and a radial hole extending from the other side end of each passage hole 25A toward the radially outer side of the rotary shaft 5 and opened on the outer peripheral surface of the rotary shaft 5 And a return hole 25D. The constricted portion 25B is formed as an annular groove extending on the outer peripheral side of the protruding shaft portion 5B over the entire circumference in order to mold the male spline 23A on the outer peripheral side of the protruding shaft portion 5B of the rotating shaft 5.

Here, one side in the axial direction of each passage hole 25A is closed using a sealing plug 26, and the sealing plug 26 blocks the passage hole 25A from an oil guide space 29 described later. A return hole 25D of the return oil passage 25 opens into the casing body 3 at a position on the other side in the axial direction from a seal member 31 described later (that is, a position closer to the bearing 6 than the seal member 31). . The return hole 25 D returns the lubricating oil introduced into the passage hole 25 A from the oil recovery space 30 described later into the casing body 3. In other words, the return hole 25D opens into the casing body 3 at a position near the bearing 6 provided between the casing body 3 and the rotary shaft 5 and has a function of guiding the recovered lubricating oil to the periphery of each bearing 6. is doing.

The annular seal groove 27 is formed on the outer peripheral side of the protruding shaft portion 5B of the rotating shaft 5. In other words, the annular seal groove 27 is located between the open end 22E of the hub 22 and the oil recovery space 30 and is provided on the outer peripheral side of the protruding shaft portion 5B of the rotating shaft 5. An O-ring 28 as a seal member is mounted in the seal groove 27. The O-ring 28 prevents lubricating oil from leaking from an oil recovery space 30 described later. The O-ring 28 seals between the inner peripheral surface of the cylindrical portion 22 A and the protruding shaft portion 5 B of the rotating shaft 5 at a position near the opening end 22 E of the hub 22.

The oil guiding space 29 is provided between the protruding shaft portion 5 B of the rotating shaft 5 and the hub 22. The oil guiding space 29 is a circular space formed between the end surface of the protruding shaft portion 5B of the rotating shaft 5 and the lid portion 22B of the hub 22. The oil guiding space 29 is disposed on one side in the axial direction of the hub 22 (that is, on the opposite side in the axial direction from the oil recovery space 30 with the spline coupling portion 23 interposed therebetween). The oil supply path 24 is open to the center side of the oil guiding space 29. The oil guiding space 29 temporarily stores the lubricating oil guided from the oil supply passage 24 and sequentially supplies the lubricating oil from the outer peripheral side of the oil guiding space 29 toward the spline coupling portion 23.

The oil recovery space 30 recovers the lubricating oil supplied to the spline coupling portion 23. The oil recovery space 30 includes a constricted portion 25B of the return oil passage 25 formed in the rotating shaft 5 and a cylindrical portion 22A of the hub 22. It is comprised from the cyclic | annular space formed between. The oil recovery space 30 is disposed on the opposite side in the axial direction with respect to the oil guide space 29 with the spline coupling portion 23 interposed therebetween. The oil recovery space 30 guides the lubricating oil discharged from the spline coupling portion 23 from the constricted portion 25B of the return oil passage 25 to the radial hole 25C. The oil recovery space 30 is sealed from the outside of the hub 22 by an O-ring 28 mounted in the seal groove 27.

The seal member 31 is provided between the shaft insertion hole 3 B of the casing body 3 and the rotary shaft 5. The seal member 31 prevents the oil in the casing 2 from leaking outside the casing body 3 along the outer peripheral surface of the rotating shaft 5. For this reason, the oil liquid (lubricating oil) returned from the return hole 25D of the return oil passage 25 into the casing body 3 flows around each bearing 6 provided between the casing body 3 and the rotary shaft 5. become.

As shown in FIG. 1, the drain plug 32 is provided in the casing body 3. The drain plug 32 is provided in the uppermost and lowermost lowermost portions of the casing body 3. The drain plug 32 is removed from the casing body 3 during maintenance of the device. Thereby, the oil liquid (drain) stored in the casing body 3 is discharged from the position of the drain plug 32 to the outside of the casing body 3 during maintenance of the device.

The oblique axis hydraulic pump 1 according to the first embodiment has the above-described configuration, and the operation thereof will be described below.

When the engine flywheel 19 serving as a drive source is rotationally driven, this rotation is transmitted to the rotary shaft 5 via the annular plate 21, the hub 22, and the spline coupling portion 23 constituting the coupling 20. In the hydraulic pump 1, the rotation of the rotary shaft 5 is transmitted from the drive disk 5 A to the cylinder block 7 via the center shaft 9, each piston 10, and each connecting rod 11.

At this time, each connecting rod 11 transmits a rotational force to the cylinder block 7 as the rotary shaft 5 (drive disk 5A) rotates, and reciprocates each piston 10 within each cylinder hole 8. As a result, each piston 10 is slidably displaced in the axial direction in the cylinder hole 8, and an intake stroke for sucking oil into the cylinder hole 8 from the valve plate 13 side and oil from the cylinder hole 8 to the valve plate 13 side. The discharge process for discharging the liquid is repeated.

When such a hydraulic pump 1 is operated, part of the oil liquid leaks from one or both of the inflow port and the outflow port of the valve plate 13. The leaked oil flows from the sliding surface of the valve plate 13 and the cylinder block 7 into the oil guide passage 9A through the center hole 7A and the radial hole 9B of the center shaft 9, for example. Thus, the oil liquid guided into the oil guide passage 9A is directed toward the oil guide space 29 between the protruding shaft portion 5B of the rotary shaft 5 and the hub 22 via the oil supply passage 24 of the rotary shaft 5. It circulates in the direction of arrow A in FIG.

The oil liquid stored in the oil guiding space 29 is supplied as a lubricating oil to the spline coupling portion 23 between the protruding shaft portion 5B of the rotating shaft 5 and the hub 22. The lubricating oil is discharged toward the oil recovery space 30 while maintaining the meshing surface between the male spline 23A and the female spline 23B in a lubricated state. The oil liquid in the oil recovery space 30 flows in the direction indicated by the arrow B in FIG. 2 from the constricted portion 25B of the return oil passage 25 to the return hole 25D through the radial hole 25C and the passage hole 25A. To the casing body 3. Further, the oil liquid flows around each bearing 6 provided between the casing body 3 and the rotary shaft 5 and accumulates inside the casing body 3 around the cylinder block 7 while lubricating each bearing 6. It becomes like this.

Thus, according to the first embodiment, in order to transmit the rotational driving force from the flywheel 19 of the engine to the rotating shaft 5, the coupling 20 includes the annular plate 21 connected to the flywheel 19 and the annular plate 21. And a covered cylindrical hub 22 connected to each other. On this, the covered cylindrical hub 22 and the protruding shaft portion 5B of the rotating shaft 5 are connected by the spline connecting portion 23. In addition, the rotary shaft 5 communicates with the oil guide passage 9A of the center shaft 9 and supplies the oil liquid in the casing body 3 to the spline coupling portion 23 in the hub 22 as lubricating oil, and the oil supply passage 24 Accordingly, a return oil passage 25 is provided for recovering the lubricating oil supplied to the spline coupling portion 23 and returning it to the casing body 3.

On the other hand, an oil guide space 29 that communicates with the oil supply passage 24 is provided on one side in the axial direction between the protruding shaft portion 5B of the rotating shaft 5 and the covered cylindrical hub 22 with the spline coupling portion 23 interposed therebetween. . An oil recovery space 30 that guides the lubricating oil discharged from the spline joint 23 to the return oil passage 25 is provided on the opposite side of the oil guide space 29 in the axial direction with the spline joint 23 interposed therebetween. Moreover, between the protruding shaft portion 5B of the rotating shaft 5 and the covered cylindrical hub 22, the oil recovery space 30 is sealed from the outside, and the lubricating oil supplied to the spline coupling portion 23 leaks to the outside. The O-ring 28 is provided to prevent this.

For this reason, the spline coupling portion 23 between the rotary shaft 5 and the hub 22 can be covered from the outside by the covered cylindrical hub 22. The oil liquid in the casing main body 3 can be supplied to the spline coupling portion 23 as lubricating oil through an oil supply passage 24 provided in the rotary shaft 5. On the other hand, the lubricating oil supplied to the spline coupling portion 23 can be recovered and returned into the casing body 3 by the return oil passage 25 provided in the rotating shaft 5. In addition, the O-ring 28 provided between the inner periphery of the hub 22 and the outer periphery of the rotating shaft 5 can prevent the lubricating oil from leaking to the outside of the hub 22.

As a result, it is not necessary to cover the outer side of the hub 22 with another cylindrical member or to provide a seal member on the outer side of the hub 22, so that the structure of the entire apparatus can be simplified and the size can be reduced. Can do. In this case, the O-ring 28 seals between the cylindrical portion 22 A of the hub 22 provided on the outer peripheral side of the protruding shaft portion 5 B of the rotating shaft 5. Therefore, an O-ring 28 that is a seal member having a smaller diameter than that of the prior art can be employed. In addition, the lubricating oil supplied to the spline coupling portion 23 can be prevented from leaking out of the hub 22 by the O-ring 28, and the sealing structure can be simplified.

Between the rotary shaft 5 and the hub 22, an oil guiding space 29 can be formed on one side in the axial direction with the spline coupling portion 23 interposed therebetween, and an oil recovery space 30 can be formed on the other side in the axial direction. The oil guiding space 29 can supply the lubricating oil to the spline coupling portion 23 in a state where the lubricating oil guided from the oil supply passage 24 of the rotating shaft 5 is temporarily stored. The oil recovery space 30 can return the lubricating oil discharged from the spline coupling portion 23 to the return oil passage 25 of the rotating shaft 5 by circulating the lubricating oil into the casing body 3.

In particular, according to the first embodiment, the coupling 20 is configured by the annular plate 21 connected to the flywheel 19 and the hub 22, and the hub 22 is constituted by the cylindrical portion 22 A and the lid portion 22 B. Is formed. In addition, a female spline 23B is formed on the inner peripheral side of the cylindrical portion 22A, and a male spline 23A that meshes with the female spline 23B is formed on the protruding shaft portion 5B of the rotating shaft 5. For this reason, the hub 22 can be formed as a covered cylindrical body in which one side in the axial direction is closed and the other side is opened across the female spline 23B. In addition, by providing an O-ring 28 between the cylindrical portion 22A of the hub 22 and the rotary shaft 5, the open end 22E side of the hub 22 can be sealed, and the lubricating oil is transferred from the inside of the hub 22 to the outside. Can be prevented from leaking.

Further, the return oil passage 25 provided in the rotating shaft 5 is opened in the casing body 3 at a position in the vicinity of the bearing 6 that supports the rotating shaft 5 so as to be rotatable in the casing body 3. For this reason, among the lubricating oil supplied to the spline coupling portion 23 by the oil supply passage 24, when the lubricating oil collected on the return oil passage 25 side is returned into the casing body 3, this lubricating oil is supplied to each bearing in the casing body 3. 6 and can be maintained in a lubricated state.

Next, FIGS. 4 to 6 show a second embodiment of the present invention. A feature of the second embodiment is that a bottomed hole extending in the axial direction is formed on the projecting end side of the rotating shaft, and the rotating member is splined inside the bottomed hole. In the second embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted.

In the figure, reference numeral 41 denotes an oblique axis type hydraulic pump as a hydraulic rotating machine employed in the second embodiment. This hydraulic pump 41 includes the casing 2 (casing body 3, head casing 4), cylinder block 7, piston 10, valve plate 13 and tilting mechanism 14 in the same manner as the hydraulic pump 1 described in the first embodiment. It is configured to include. However, the hydraulic pump 41 in this case is different from the first embodiment in that the bottomed hole 42C is formed on the protruding end (that is, the protruding cylindrical portion 42B) side of the rotating shaft 42 described later. ing.

Reference numeral 42 denotes a rotating shaft employed in the second embodiment. The rotating shaft 42 is configured in substantially the same manner as the rotating shaft 5 described in the first embodiment, and one end side in the axial direction has a shaft insertion hole. Projecting from 3B to the outside of the casing body 3. A drive disk 42A is provided on the other axial end side of the rotating shaft 42, and the center shaft 9 and the plurality of connecting rods 11 are swingably connected to the drive disk 42A.

However, the rotary shaft 42 in this case has a protruding cylindrical portion 42B that protrudes in a cylindrical shape toward the outside of the casing body 3 at one end side in the axial direction, and has a bottomed hole extending in the axial direction inside the protruding cylindrical portion 42B. 42C is formed. Thereby, the protrusion cylinder part 42B of the rotating shaft 42 is formed as a bottomed cylindrical body. In other words, the protruding cylindrical portion 42B is closed with one side (projecting end) in the axial direction serving as an open end 42D and the other side in the axial direction serving as a bottom surface 42E of the bottomed hole 42C. A female spline 47B of a spline coupling portion 47, which will be described later, is formed on the inner peripheral side of the protruding cylindrical portion 42B.

Reference numeral 43 denotes a flywheel employed in the second embodiment. The flywheel 43 is configured in substantially the same manner as the flywheel 19 described in the first embodiment, and is a crankshaft (see FIG. (Not shown) and rotationally driven integrally. The rotation of the flywheel 43 is transmitted to the rotating shaft 42 of the hydraulic pump 41 via a coupling 44 described later.

44 is a coupling for transmitting the rotation of the flywheel 43 to the rotating shaft 42 of the hydraulic pump 41, and the coupling 44 constitutes a rotating member on the drive source side. The coupling 44 includes an annular plate 45 made of an annular flat plate material and a boss member 46 described later. As shown in FIG. 4, the outer peripheral side of the annular plate 45 of the coupling 44 is detachably fixed to the flywheel 43 using a plurality of fasteners 45 A (for example, bolts). A boss member 46 described later is detachably fixed to the inner peripheral side of the annular plate 45 using a plurality of fasteners 45B (for example, rivets or bolts).

The boss member 46 constitutes a part of the coupling 44. As shown in FIGS. 5 and 6, the boss member 46 includes a cylindrical lid portion 46A, an annular flange portion 46B extending radially outward from one outer periphery of the lid portion 46A, and a lid portion 46A. The shaft portion 46C extends to the other side in the axial direction and is formed with a smaller diameter than the lid portion 46A. A male spline 47A, which will be described later, is formed on the shaft portion 46C of the boss member 46, whereby the boss member 46 is splined to the protruding cylindrical portion 42B of the rotating shaft 42. A constricted portion 46D formed of an annular stepped portion is provided between the lid portion 46A and the shaft portion 46C of the boss member 46, and the constricted portion 46D forms an oil recovery space 54 described later. The constricted portion 46 D is formed as an annular groove extending over the entire circumference of the boss member 46 in order to form a male spline 47 A (described later) on the outer peripheral side of the shaft portion 46 C of the boss member 46.

5 and 6, a plurality of fastener insertion holes 46E are formed in the flange portion 46B of the boss member 46, and the fasteners 45B are inserted into the fastener insertion holes 46E, respectively. These fasteners 45 B fasten the flange 46 B of the boss member 46 to the inner peripheral side of the annular plate 45. Thereby, the boss member 46 of the coupling 44 is connected to the flywheel 43 via the annular plate 45 and rotates integrally with the flywheel 43. The lid portion 46A of the boss member 46 is inserted into the protruding cylindrical portion 42B of the rotating shaft 42 together with the shaft portion 46C from the opening end 42D side. At this time, the lid portion 46A is connected to the opening end 42D side of the rotating shaft 42. Is closed (see FIG. 5). The coupling 44 may be configured such that the annular plate 45 and the boss member 46 are integrally formed.

47 is a spline coupling portion for connecting the protruding cylindrical portion 42B of the rotating shaft 42 to the boss member 46. The spline coupling portion 47 is provided on the inner peripheral side of the protruding cylindrical portion 42B of the rotating shaft 42 so as to mesh with the male spline 47A provided on the outer periphery of the shaft portion 46C of the boss member 46. It is comprised by the female spline 47B.

Here, an oil recovery space 54 described later is formed on one side in the axial direction across the spline coupling portion 47 between the protruding cylindrical portion 42B of the rotating shaft 42 and the boss member 46, and on the other side in the axial direction. Is formed with an oil guide space 53 to be described later. Lubricating oil is supplied to the spline coupling portion 47 from the oil guiding space 53 side. This lubricating oil keeps the meshing surfaces of the male spline 47A and the female spline 47B in a lubricated state while flowing toward the oil recovery space 54.

The oil supply passage 48 is provided at the axial center position of the rotary shaft 42. That is, the oil supply passage 48 is formed as an axial passage extending in the axial direction of the rotating shaft 42. One side of the oil supply passage 48 opens to the bottom surface 42E of the rotating shaft 42 so as to communicate with an oil guide space 53 described later. The other side of the oil supply passage 48 communicates with the oil guide passage 9A of the center shaft 9 on the center side of the drive disk 42A. Thereby, the oil supply path 48 distributes the oil liquid guided into the oil guide path 9 A toward the oil guide space 53.

A plurality of return oil passages 49 are provided on the rotating shaft 42. These return oil passages 49 are a plurality (for example, two) of the return oil passages 49 that are formed to extend in the axial direction of the protruding cylindrical portion 42 B (the rotation shaft 42) at positions spaced from the oil supply passage 48 in the radial direction of the rotation shaft 42. A passage hole 49A, a radial hole 49B formed so as to extend in the radial direction of the protruding cylinder portion 42B so as to communicate the constricted portion 46D of the boss member 46 with each passage hole 49A, and the other side end portion of each passage hole 49A And a radial return hole 49 C that extends outward in the radial direction of the rotary shaft 42 and opens on the outer peripheral surface of the rotary shaft 42.

Here, one side in the axial direction of each passage hole 49A is closed using a sealing plug 50, and the sealing plug 50 blocks the passage hole 49A from an oil guide space 53 described later. A sealing plug 50 is also provided in the radial hole 49B, and the sealing plug 50 seals the radial hole 49B on the outer peripheral side of the protruding cylindrical portion 42B.

The return hole 49C of the return oil passage 49 opens into the casing body 3 at a position that is on the other side in the axial direction than the seal member 31 (that is, a position that is closer to the bearing 6 than the seal member 31). The return hole 49C returns the lubricating oil introduced into the passage hole 49A from an oil recovery space 54 described later into the casing body 3. In other words, the return hole 49 C opens into the casing body 3 at a position near the bearing 6 provided between the casing body 3 and the rotating shaft 42, and has a function of guiding the recovered lubricating oil around each bearing 6. is doing.

The annular seal groove 51 is formed on the outer periphery of the lid portion 46 A of the boss member 46. An O-ring as a seal member is mounted in the seal groove 51. The O-ring 52 prevents lubricating oil from leaking outside from an oil recovery space 54 described later. Therefore, the O-ring 52 is provided between the opening end 42D of the rotating shaft 42 (projecting cylinder portion 42B) and the oil recovery space 54, and is provided in the lid portion 46A of the boss member 46. The space between the protruding cylindrical portion 42B of the rotating shaft 42 and the lid portion 46A of the boss member 46 is sealed.

The oil guiding space 53 is provided between the protruding cylindrical portion 42 B of the rotating shaft 42 and the boss member 46. That is, the oil guiding space 53 is a circular space formed between the bottom surface 42E of the bottomed hole 42C of the rotating shaft 42 and the shaft portion 46C of the boss member 46. The oil guiding space 53 is disposed on the other side in the axial direction of the boss member 46 with the spline coupling portion 47 interposed therebetween. The oil guiding space 53 temporarily stores the lubricating oil guided from the oil supply passage 48 and sequentially supplies the lubricating oil from the outer peripheral side of the oil guiding space 53 toward the spline coupling portion 47.

The oil recovery space 54 recovers the lubricating oil supplied to the spline coupling portion 47, and the oil recovery space 54 includes a protruding cylindrical portion 42 B (bottomed hole 42 C) of the rotating shaft 42 and a constricted portion 46 D of the boss member 46. It is comprised as an annular space formed between the two. The oil recovery space 54 is disposed on the opposite side in the axial direction from the oil guide space 53 with the spline coupling portion 47 interposed therebetween. The oil recovery space 54 guides the lubricating oil discharged from the spline coupling portion 47 to each radial hole 49 B of the return oil passage 49. The oil recovery space 54 is sealed against the outside of the boss member 46 by an O-ring 52 mounted in the seal groove 51.

Thus, in the second embodiment configured as described above, the lid portion 46A of the boss member 46 is inserted into the projecting cylindrical portion 42B of the rotating shaft 42 together with the shaft portion 46C. As a result, the projecting cylindrical portion 42 B of the rotating shaft 42 and the shaft portion 46 C of the boss member 46 are connected by the spline coupling portion 47. As a result, also in the second embodiment, it is possible to obtain the same operational effects as in the first embodiment described above.

That is, in the second embodiment, the spline coupling portion 47 between the protruding cylindrical portion 42B of the rotating shaft 42 and the boss member 46 can be covered from the outside by the protruding cylindrical portion 42B of the rotating shaft 42. To the spline coupling portion 47, the oil liquid in the casing body 3 can be supplied as lubricating oil through an oil supply passage 48 provided in the rotating shaft 42. On the other hand, the lubricating oil supplied to the spline coupling portion 47 can be recovered and returned into the casing body 3 by the return oil passage 49 provided in the rotating shaft 42. In addition, since the O-ring 52 is provided between the projecting cylindrical portion 42B of the rotating shaft 42 and the lid portion 46A of the boss member 46, the O-ring 52 allows the lubricating oil to flow from the opening end 42D side of the projecting cylindrical portion 42B. It is possible to prevent leakage to the outside.

Particularly, in the second embodiment, an O-ring 52 as a seal member is provided not on the rotary shaft 42 but on the lid portion 46A of the boss member 46 via the seal groove 51. For this reason, it is possible to increase the degree of freedom in layout design in providing the lubricating oil supply passage 48 and the return oil passage 49 in the protruding cylindrical portion 42B of the rotating shaft 42. In addition, it is possible to ensure a sufficient passage diameter (flow passage area) for providing the return oil passage 49 in the protruding cylindrical portion 42B.

Next, FIG. 7 shows a third embodiment of the present invention. The hydraulic rotating machine according to the third embodiment is applied to a variable displacement swash plate type hydraulic pump. On this basis, the feature of the third embodiment resides in that the rotary shaft of the swash plate hydraulic pump is splined to the rotary member on the drive source side. Note that in the third embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted.

In the figure, reference numeral 61 denotes a swash plate type hydraulic pump as a hydraulic rotating machine adopted in the third embodiment, and the hydraulic pump 61 is composed of a variable displacement swash plate type hydraulic pump. Here, the hydraulic pump 61 includes a casing 62, a rotating shaft 63, a cylinder block 66, a plurality of cylinder holes 67, a piston 68, a shoe 69, a valve plate 71, a swash plate support 72, and a swash plate 73, which will be described later. Has been.

Reference numeral 62 denotes a cylindrical casing constituting the outer shell of the hydraulic pump 61. The casing 62 includes a cylindrical casing main body 62A, a front casing 62B and a rear casing 62C in which both ends of the casing main body 62A are closed. Has been. The casing main body 62A may be formed integrally with either the front casing 62B or the rear casing 62C.

The front casing 62B located on one side of the casing main body 62A is provided with a swash plate support portion 72, which will be described later, facing the back side of the swash plate 73. A pair of supply / discharge passages (both not shown) are formed in the rear casing 62C located on the other side of the casing body 62A. Of these supply / discharge passages, the low-pressure supply / discharge passage serves as a suction passage for sucking oil in a tank (not shown), and the high-pressure supply / discharge passage constitutes a discharge passage for discharging pressure oil. To do.

63 is a rotating shaft provided rotatably in the casing 62, and the rotating shaft 63 is rotatably supported by the front casing 62B and the rear casing 62C via

bearings

64 and 65, respectively. The rotating shaft 63 is inserted into a center hole 66A of a cylinder block 66 described later, and rotates integrally with the cylinder block 66. One end side of the rotating shaft 63 is a protruding shaft portion 63A that protrudes in the axial direction from the front casing 62B, and a spline is formed on the outer peripheral side of the protruding shaft portion 63A in the same manner as the rotating shaft 5 described in the first embodiment. A male spline 23A (see FIG. 2) of the coupling portion 23 is formed.

The cylinder block 66 is provided in the casing 62 so as to rotate integrally with the rotating shaft 63. The cylinder block 66 is formed as a circular rotating body, and a center hole 66A is bored in the axial direction at the axial center position. The cylinder block 66 is formed with a plurality of cylinder holes 67 that are spaced apart from each other in the circumferential direction around the center hole 66A and extend in the axial direction.

The plurality of pistons 68 are slidably inserted into the cylinder holes 67 of the cylinder block 66, respectively. These pistons 68 reciprocate in the cylinder hole 67 as the cylinder block 66 rotates, and repeat the suction stroke and the discharge stroke. A shoe 69 is provided on one side (projecting end side) of each piston 68. These shoes 69 are swingably attached to the projecting end side of the piston 68 projecting in the axial direction of the rotary shaft 63 from the cylinder hole 67 of the cylinder block 66.

The annular shoe presser 70 is a member that holds each shoe 69 against the swash plate 73. The shoe presser 70 presses the shoe 69 toward a smooth surface 73A of a swash plate 73 described later by a spring 70A. Thus, the shoe presser 70 compensates for the sliding displacement of each shoe 69 so as to draw an annular locus on the smooth surface 73A of the swash plate 73.

The valve plate 71 is located in the casing 62 and is provided between the rear casing 62C and the cylinder block 66 and fixed to the rear casing 62C. The end face of the cylinder block 66 that rotates integrally with the rotary shaft 63 is in sliding contact with the valve plate 71. The valve plate 71 is formed with a pair of inflow and outflow ports having an eyebrow shape, and these inflow and outflow ports communicate with the pair of supply / exhaust passages of the rear casing 62C described above.

Here, in the intake stroke of the piston 68, oil is sucked into each cylinder hole 67 from the inflow port of the valve plate 71, and in the discharge stroke, the oil liquid flows from each cylinder hole 67 toward the outflow port of the valve plate 71. Is discharged. At this time, part of the fluid leaks from one or both of the inflow port and the outflow port of the valve plate 71, and this leaked oil flows into the cylinder block 66 from the sliding surface of the valve plate 71 and the cylinder block 66, for example. It circulates in the oil supply passage 77 of the rotating shaft 63 through the center hole 66A.

The swash plate support 72 is located around the rotating shaft 63 and is provided in the front casing 62B. The swash plate 73 is supported in the casing 62 so as to be tiltable by the swash plate support 72. The surface of the swash plate 73 is a smooth surface 73A that guides each shoe 69 in a slidable manner. The swash plate 73 is driven to tilt using

tilt actuators

74 and 75 described later, and the discharge capacity (pressure oil discharge flow rate) of the hydraulic pump 61 is variably controlled according to the tilt angle of the swash plate 73. Is.

A pair of tilting

actuators

74 and 75 drive the swash plate 73 to tilt. The tilting

actuators

74 and 75 are disposed at positions facing each other in the casing main body 62 A and outside the cylinder block 66 in the radial direction. The tilt actuators 74 and 75 are configured to tilt the swash plate 73 by

tilt pistons

74A and 75A.

Reference numeral 76 denotes a cylindrical housing employed in the third embodiment, and the housing 76 is an engine (not shown) that is a drive source of the hydraulic pump 61 in substantially the same manner as the housing 18 described in the first embodiment. Z)). An outer peripheral side of the front casing 62B is detachably fastened to the housing 76 using a plurality of bolts 76A. Thereby, the casing 62 of the hydraulic pump 61 is fixedly attached to the housing 76 of the engine. Inside the housing 76, the flywheel 19 is provided as described in the first embodiment. The flywheel 19 is provided with an annular plate 21 and a hub 22 that constitute a coupling 20 as a rotating member.

Here, the protruding shaft portion 63A side of the rotating shaft 63 is inserted into the cylindrical portion 22A of the hub 22. The cylindrical portion 22A of the hub 22 and the protruding shaft portion 63A of the rotating shaft 63 are connected by the spline coupling portion 23 described in the first embodiment. In the hub 22, an oil guiding space 29 is formed on one side in the axial direction across the spline coupling portion 23, and an oil recovery space 30 is formed on the other side in the axial direction. Lubricating oil is supplied to the spline coupling portion 23 from the oil guiding space 29 side. This lubricating oil keeps the spline coupling portion 23 in a lubrication state while flowing toward the oil recovery space 30.

The oil supply passage 77 is provided at the axial center position of the rotating shaft 63. The oil supply passage 77 is formed as an axial passage extending in the axial direction of the rotating shaft 63. One side of the oil supply passage 77 is opened at one end surface of the rotary shaft 63 so as to communicate with the oil guide space 29. The other side of the oil supply passage 77 communicates with a radial hole 77A extending through the rotary shaft 63 in the radial direction. Here, the radial hole 77 A constitutes a guide hole through which the oil leaked into the center hole 66 A of the cylinder block 66 flows into the oil supply passage 77 of the rotating shaft 63.

That is, in the center hole 66 A of the cylinder block 66, for example, an oil liquid in a relatively high pressure state leaks from the sliding surface between the cylinder block 66 and the valve plate 71. The leaked oil is in a higher pressure state than the oil liquid stored in the casing 62 outside the cylinder block 66. The leaked oil having a high pressure is guided from the center hole 66A into the oil supply passage 77 through the radial holes 77A of the rotating shaft 63. Thereby, the oil supply passage 77 distributes the oil liquid guided from the center hole 66 A toward the oil introduction space 29.

A plurality of return oil passages 78 are provided on the rotating shaft 63. These return oil passages 78 are configured in the same manner as the return oil passage 25 described in the first embodiment, and return the lubricating oil recovered in the oil recovery space 30 into the casing body 3 as described above. . The return oil path 78 opens into the casing 62 at a position in the vicinity of the bearing 64 provided between the front casing 62 B and the rotating shaft 63, and also has a function of guiding the recovered lubricating oil to the periphery of the bearing 64.

Between the cylindrical portion 22A of the hub 22 and the protruding shaft portion 63A of the rotating shaft 63, an O-ring 28 is provided between the open end 22E of the hub 22 and the oil recovery space 30. The O-ring 28 has a function of preventing the lubricating oil from leaking from the oil recovery space 30 to the outside of the hub 22 as described in the first embodiment.

The seal member 79 is provided between the front casing 62B and the rotating shaft 63. The seal member 79 prevents the oil in the casing 62 from leaking to the outside (that is, the hub 22 side) along the outer peripheral surface of the rotating shaft 63. For this reason, the oil returned to the casing 62 from the return oil passage 78 circulates around the bearing 64 provided between the front casing 62B and the rotating shaft 63 and around the cylinder block 66 inside the casing 62. It will be accumulated in.

Thus, the third embodiment configured as described above is configured as a variable displacement swash plate type hydraulic pump 61. In this case, the spline coupling portion 23 provided between the protruding shaft portion 63A of the rotating shaft 63 and the cylindrical portion 22A of the hub 22 can be configured to be covered from the outside by the covered cylindrical hub 22, which is a first embodiment. An effect similar to that of the embodiment can be obtained. That is, since it is not necessary to cover the outer side of the hub 22 with another cylindrical member or to provide a separate sealing member, the structure of the entire apparatus can be simplified and the size can be reduced.

Next, FIG. 8 shows a fourth embodiment of the present invention. A feature of the fourth embodiment is that a plurality of hydraulic pumps are driven by a rotation member on the drive source side. Note that in the fourth embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted.

In the figure, reference numeral 81 denotes a slanted shaft type first hydraulic pump employed in the fourth embodiment. The first hydraulic pump 81 is configured in substantially the same manner as the hydraulic pump 1 described in the first embodiment. ing. The first hydraulic pump 81 includes a cylinder block 7, a plurality of cylinder holes 8, a center shaft 9, a piston 10, a connecting rod 11, a valve plate 13, a tilting mechanism 14, a casing 82 described later, and a rotating shaft 84. ing.

82 is a casing of the hydraulic pump 81, and the casing 82 is composed of the casing body 83 and the head casing 4 in the same manner as the casing 2 described in the first embodiment. However, the casing 82 in this case is different from the casing body 3 described in the first embodiment in the shape of the mounting flange 83A in the casing body 83. Further, the casing main body 83 is provided with a shaft insertion hole 83B through which a rotation shaft 84 described later is inserted on the inner peripheral side of the mounting flange 83A. The other side of the casing body 83 in the axial direction is a head side end portion 83C to which the head casing 4 is attached in an abutting state.

Reference numeral 84 denotes a rotating shaft employed in the fourth embodiment. The rotating shaft 84 is configured in substantially the same manner as the rotating shaft 5 described in the first embodiment, and a drive disk 84A is provided at the other end in the axial direction. Is provided. One end side of the rotating shaft 84 is a protruding shaft portion 84B that protrudes outside the casing body 83 from the shaft insertion hole 83B. However, the protruding shaft portion 84B of the rotating shaft 84 is formed to be long compared to the first embodiment. A drive gear 94 (described later) is fixedly provided at an intermediate portion of the protruding shaft portion 84B of the rotation shaft 84. The rotary shaft 84 is provided with an oil supply passage 24 and return oil passages 25 in the same manner as the rotary shaft 5 described in the first embodiment. On the outer peripheral side of the protruding shaft portion 84B of the rotating shaft 84, a spline coupling portion 23 is provided between the hub 22 on the engine side.

85 is an oblique second hydraulic pump provided in parallel with the first hydraulic pump 81, and the second hydraulic pump 85 is configured in the same manner as the first hydraulic pump 81. The second hydraulic pump 85 includes a cylinder block 7, a plurality of cylinder holes 8, a center shaft 9, a piston 10, a connecting rod 11, a valve plate 13, a tilt mechanism 14, and a casing 82. However, the first and second

hydraulic pumps

81 and 85 employed in the fourth embodiment constitute what is called a double pump.

The second hydraulic pump 85 is different from the rotary shaft 84 of the first hydraulic pump 81 in the shape of the rotary shaft 86. That is, the rotation shaft 86 of the second hydraulic pump 85 is provided with a drive disk 86A on the other axial end side, and one end side of the rotation shaft 86 is a protruding shaft portion 86B that protrudes outside the casing body 83. However, the protruding shaft portion 86 B of the rotating shaft 86 is formed shorter than the rotating shaft 84 of the first hydraulic pump 81. A driven gear 95, which will be described later, is fixed on the outer peripheral side of the protruding shaft portion 86B of the rotating shaft 86 by spline coupling.

The oil passage 87 is a lubricating oil passage provided on the rotating shaft 86. The oil passage 87 is formed as an axial passage extending in the axial direction of the rotary shaft 5. The oil passage 87 communicates with the oil guide passage 9A of the center shaft 9 at the axial center position of the drive disk 86A. The distal end side of the oil passage 87 extends toward the radially outer side of the rotating shaft 86 and opens on the outer peripheral surface of the rotating shaft 86. That is, the oil passage 87 opens into the casing body 83 at a position near the bearing 6 provided between the casing body 83 and the rotating shaft 86. The oil passage 87 has a function of guiding lubricating oil around each bearing 6.

Reference numeral 88 denotes a cylindrical housing employed in the fourth embodiment, and the housing 88 is an engine (a driving source of the hydraulic pumps 81 and 85) substantially similar to the housing 18 described in the first embodiment. (Not shown). The outer peripheral side of the gear box 89 is detachably fastened to the housing 88 using a plurality of bolts 88A.

Here, the gear box 89 has a partition plate 89B provided with a shaft insertion hole 89A, and extends from the outer peripheral side of the partition plate 89B toward the

hydraulic pumps

81 and 85. One or a plurality of side plates 89C formed in a cylindrical shape surrounding from the outside in the direction, and a closing plate connected to the partition plate 89B via the side plate 89C and facing the partition plate 89B in the front and rear directions 89D. A mounting hole 89E for mounting the first and second

hydraulic pumps

81 and 85 is formed in the closing plate 89D of the gear box 89.

The first and second

hydraulic pumps

81 and 85 are detachably fixed to the gear box 89 so that the mounting flange 83A of each casing body 83 closes the mounting hole 89E of the closing plate 89D. Thus, the first and second

hydraulic pumps

81 and 85 are fixedly attached to the engine housing 88 via the gear box 89.

At this time, in the first hydraulic pump 81, the protruding shaft portion 84B of the rotating shaft 84 is inserted into the housing 88 via the shaft insertion hole 89A of the gear box 89. A space between the rotary shaft 84 and the shaft insertion hole 89A is liquid-tightly sealed by a seal member 90. That is, lubricating oil is accommodated in the gear box 89 in order to lubricate meshing portions of

gears

94 and 95 described later. The seal member 90 prevents the lubricating oil in the gear box 89 from leaking to the housing 88 side.

Inside the housing 88, a flywheel 91 substantially the same as the flywheel 19 described in the first embodiment is provided. The flywheel 91 is provided with a coupling 92 as a rotating member for transmitting the rotation of the engine to the rotating shaft 84 of the first hydraulic pump 81. The coupling 92 includes an annular plate 93 and the hub 22. Here, the annular plate 93 of the coupling 92 is detachably fixed to the flywheel 91 via a plurality of fasteners 93A (for example, bolts). As in the first embodiment, the hub 22 is detachably fixed to the inner peripheral side of the annular plate 93 using a plurality of fasteners 93B. In addition, the coupling 92 is good also as a structure which forms the annular plate 93 and the hub 22 as an integrated object.

Here, the protruding shaft portion 84B side of the rotating shaft 84 is inserted into the cylindrical portion 22A of the hub 22, and the cylindrical portion 22A of the hub 22 and the protruding shaft portion 84B of the rotating shaft 84 are the first embodiment. They are connected by the spline connecting portion 23 described in the above. In the hub 22, an oil guiding space 29 is formed on one side in the axial direction across the spline coupling portion 23, and an oil recovery space 30 is formed on the other side in the axial direction. Lubricating oil is supplied to the spline coupling portion 23 from the oil guiding space 29 side, and this lubricating oil keeps the spline coupling portion 23 in a lubrication state while flowing toward the oil recovery space 30.

The drive gear 94 is disposed in the gear box 89. The drive gear 94 is fixedly provided on the outer peripheral side of the intermediate portion of the projecting shaft portion 84B of the rotating shaft 84 by spline coupling. Further, a driven gear 95 that meshes with the drive gear 94 is disposed in the gear box 89. The driven gear 95 is fixed to the outer peripheral side of the projecting shaft portion 86B of the rotating shaft 86 of the second hydraulic pump 85 by spline coupling. A plurality of driven gears 95 may be provided so as to mesh with the drive gear 94. In this case, the second hydraulic pump 85 can be increased by the number of the driven gears 95.

Thus, in the fourth embodiment configured as described above, when the flywheel 91 of the engine serving as a drive source is rotationally driven, this rotation is transmitted via the annular plate 93 of the coupling 92, the hub 22 and the spline coupling portion 23. Is transmitted to the rotary shaft 84. In the first hydraulic pump 81, the rotation of the rotary shaft 84 is transmitted from the drive disk 84 A to the cylinder block 7 through the center shaft 9, each piston 10, and each connecting rod 11.

At this time, in the gear box 89, the rotation of the drive gear 94 is transmitted to the driven gear 95, and the rotation shaft 86 of the second hydraulic pump 85 is rotationally driven integrally with the driven gear 95. Therefore, the first and second

hydraulic pumps

81 and 85 transmit the rotational force to the cylinder block 7 along with the rotation of the rotation shafts 84 and 86 (

drive disks

84A and 86A) in the respective casings 82, and each piston. 10 is reciprocated in each cylinder hole 8.

As a result, each piston 10 is slidably displaced in the axial direction in the cylinder hole 8, and an intake stroke for sucking oil into the cylinder hole 8 from the valve plate 13 side and oil from the cylinder hole 8 to the valve plate 13 side. The discharge process for discharging the liquid is repeated. As a result, the first hydraulic pump 81 and the second hydraulic pump 85 can be driven by a single drive source, and each

pump

81, 85 can discharge pressure oil separately.

Also in the fourth embodiment configured as described above, the spline coupling portion 23 provided between the protruding shaft portion 84B of the rotating shaft 84 and the cylindrical portion 22A of the hub 22 is provided outside by the covered cylindrical hub 22. It can be set as the structure covered from this, and there can exist an effect similar to 1st Embodiment. That is, since it is not necessary to cover the outer side of the hub 22 with another cylindrical member or to provide a separate sealing member, the structure of the entire apparatus can be simplified and the size can be reduced.

In the fourth embodiment, the case where the first and second

hydraulic pumps

81 and 85 are configured by variable displacement oblique shaft type hydraulic rotating machines has been described as an example. However, the present invention is not limited to this. For example, as described in the third embodiment, the first and second hydraulic pumps may be configured using a variable displacement swash plate type hydraulic rotating machine. The same change can be made for the second embodiment.

Further, the present invention is not limited to a variable displacement hydraulic pump, but can also be applied to a fixed displacement hydraulic pump. Furthermore, the present invention is not limited to a hydraulic pump, and may be applied to, for example, a variable displacement type or a fixed displacement type hydraulic motor. In this case, for example, the first to third implementations of the counterpart rotating body (for example, the rotating shaft of the reduction gear, the blower, and the generator) that are rotationally driven by the rotating shaft of the hydraulic motor are performed with respect to the rotating shaft of the hydraulic motor. What is necessary is just to set it as the structure connected using a spline coupling | bond part as described in the form.

Furthermore, in the first embodiment, after the oil liquid that has lubricated the spline coupling portion 23 is returned from the oil recovery space 30 into the casing body 3 through the oil passage 25, the oil liquid is discharged to the tank side. The case where it does is explained as an example. However, the present invention is not limited to this. For example, the oil returned to the casing body 3 may be used as the suction oil of the pump without being discharged into the tank. This also applies to the second to fourth embodiments.

1,41,61,81,85 Hydraulic pump (hydraulic rotating machine)
2, 62, 82

Casing

3, 62A, 83 Casing body 4

Head casing

5, 42, 63, 84

Rotating shaft

5A, 42A,

84A Drive disk

5B, 63A, 84B Projecting shaft (projecting end)
6, 64

Bearing

7, 66

Cylinder block

7A,

66A Center hole

8, 67 Cylinder hole 9

Center shaft

10, 68

Piston

13, 71

Valve plate

18, 76, 88

Housing

19, 43, 91

Flywheel

20, 44, 92

Cup Rings

21, 45, 93 Annular plate 22 Hub

22A Tube portion

22B Lid portion

22E Open end

23, 47

Spline coupling portion

23A,

47A Male spline

23B,

47B Female spline

24, 48, 77

Oil supply passage

25, 49, 78 Return oil passage 28,52 O-ring (seal member)
29, 53

Oil guide space

30, 54 Oil recovery space 42B Projecting cylinder portion 42C Bottomed hole 42D Open end 42E Bottom surface 46 Boss member (rotating member)

Claims

A cylindrical casing (2, 62, 82) and a rotary shaft (5, 42, 63, 84) rotatably provided on the casing (2, 62, 82) via bearings (6, 64, 65). ) And a plurality of cylinder holes (in the casing (2, 62, 82) so as to rotate integrally with the rotating shaft (5, 42, 63, 84) and spaced apart in the circumferential direction and extending in the axial direction ( 8, 67) and a plurality of cylinder blocks (7, 66) inserted into the cylinder holes (8, 67) of the cylinder block (7, 66) so as to be reciprocally movable from one side in the axial direction. The piston (10, 68) is located between the casing (2, 62, 82) and the other axial side of the cylinder block (7, 66) and the casing (2, 62, 82). Actuating intermittently in communication with each cylinder hole (8, 67) Valve plate (13, 71) in which the inflow port and the outflow port are formed, and a drive source for rotationally driving the rotary shaft (5, 42, 63, 84) or the rotary shaft (5, 42, 63, 84). And a coupling (20, 44, 92) for connecting the rotating shaft (5, 42, 63, 84) to the rotating body that is rotationally driven by
In the hydraulic rotating machine formed by connecting the rotating shaft (5, 42, 63, 84) and the coupling (20, 44, 92) using a spline coupling portion (23, 47),
The rotating shaft (5, 42, 63, 84) has the casing (2, 62,) with respect to the spline coupling portion (23, 47) formed between the coupling (20, 44, 92). 82) The oil supply passage (24, 48, 77) for supplying the hydraulic oil in the oil as the lubricant, and the lubricating oil supplied to the spline joint (23, 47) by the oil supply passage (24, 48, 77). A return oil passage (25, 49, 78) that is recovered and returned into the casing (2, 62, 82);
Between the coupling (20, 44, 92) and the rotating shaft (5, 42, 63, 84), the lubricating oil supplied to the spline coupling part (23, 47) is leaked to the outside. A hydraulic rotating machine characterized in that a sealing member (28, 52) for preventing is provided.
Between the coupling (20, 44, 92) and the rotating shaft (5, 42, 63, 84), the oil supply is arranged on one side in the axial direction with the spline coupling portion (23, 47) interposed therebetween. An oil guide space (29, 53) for guiding the lubricating oil supplied from the passage (24, 48, 77) to the spline joint (23, 47) and the spline joint (23, 47) are sandwiched between the oil guide space (29, 53). An oil recovery space (30, 54) is provided which is disposed on the opposite side of the oil space (29, 53) in the axial direction and guides the lubricating oil discharged from the spline coupling portion (23, 47) to the return oil passage. The hydraulic rotary machine according to claim 1, wherein the seal member (28, 52) is configured to seal the oil recovery space (30, 54) from the outside.
The return oil passage (25, 49, 78) is in relation to the bearing (6, 64) supporting the rotating shaft (5, 42, 63, 84) rotatably in the casing (2, 62, 82). The hydraulic rotating machine according to claim 1, wherein the hydraulic rotating machine is configured to open into the casing (2, 62, 82) at a position near the bearing (6, 64) so as to guide the recovered lubricating oil.
The oil supply passage (24, 48, 77) supplies hydraulic oil leaked from one or both of the inflow port and the outflow port of the valve plate (13, 71) to the spline joint (23, 47). The hydraulic rotating machine according to claim 1, wherein the hydraulic rotating machine is configured.
The oil supply passages (24, 48, 77) pass hydraulic oil leaked from the sliding surfaces of the cylinder block (7, 66) and the valve plate (13, 71) to the spline joints (23, 47). The hydraulic rotating machine according to claim 1, wherein the hydraulic rotating machine is configured to supply.
The spline coupling portion (23, 47) is a female spline (23B) provided on the inner peripheral side of one of the coupling (20, 44, 92) and the rotating shaft (5, 42, 63, 84). , 47B) and male splines (23A, 47A) provided on the outer peripheral side of the other member so as to mesh with the female splines (23B, 47B),
The one member is formed as a covered cylindrical body or a bottomed cylindrical body in which one side in the axial direction is closed and the other side is opened across the female spline (23B, 47B),
The hydraulic rotating machine according to claim 1, wherein the sealing member (28, 52) is configured to seal an opening side of the one member.
The spline coupling portion (23) includes a female spline (23B) provided on the inner peripheral side of the coupling (20, 92) and the rotating shaft (5, 63) so as to mesh with the female spline (23B). , 84) and a male spline (23A) provided on the outer peripheral side,
The coupling (20, 92) is formed as a covered cylindrical body with one side in the axial direction closed and the other side opened with the female spline (23B) in between.
The hydraulic rotary machine according to claim 1, wherein the sealing member (28) is configured to seal an opening side of the coupling (20, 92).
The spline coupling portion (47) includes a female spline (47B) provided on the inner peripheral side of the rotating shaft (42) and an outer peripheral side of the coupling (44) so as to mesh with the female spline (47B). And a male spline (47A) provided in the
The rotating shaft (42) is formed as a bottomed cylindrical body that is open on one side in the axial direction and closed on the other side across the female spline (47B),
The hydraulic rotary machine according to claim 1, wherein the sealing member (52) is configured to seal an opening side of the rotating shaft (42).