JPH0720384Y2 - Variable capacity oblique shaft type hydraulic rotary machine - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to improvement of a variable displacement type oblique shaft type hydraulic rotary machine as a hydraulic pump and a hydraulic motor used in civil engineering / construction machinery and other general machines.

[Prior art]

FIG. 6 shows a hydraulic pump as an oblique shaft type hydraulic rotary machine according to the prior art.

In the figure, reference numeral 1 is a substantially cylindrical casing body 1A, and a head casing 1B for closing an opening of the casing body 1A.
And a rotating shaft rotatably supported in the casing body 1A, and 3 is the casing body 1A.
A cylinder block located inside and rotating with the rotary shaft 2, and a plurality of cylinders 4 are bored in the cylinder block 3 in the axial direction. A piston 5 is slidably provided in each cylinder 4, and a connecting rod 6 is attached to each piston 5. A spherical portion 6A is formed at the tip of each connecting rod 6, and the spherical portion 6A is swingably supported by a drive disk 7 formed at the tip of the rotary shaft 2.

Reference numeral 8 denotes a valve plate, and one end face of the valve plate 8 is in sliding contact with the cylinder block 3 and the other end face thereof is a concave arc shape centered on a tilt center O ₁ described later formed on the head casing 1B. Slidably slidably contacting the tilt sliding surface 9 of
A through hole 8A is formed at the center of the valve plate 8 into which the tip ends of a center shaft 10 and a swing pin 15 described later are inserted from both sides.
Has been drilled. The valve plate 8 is provided with a supply / discharge port (not shown) intermittently communicating with each cylinder 4 by the rotation of the cylinder block 3, and the supply / discharge port is a tilted position of the valve plate 8. Head casing 1B regardless of
It is adapted to communicate with a supply / discharge passage (not shown) that opens to the tilt sliding surface 9.

Reference numeral 10 is a center shaft for supporting the cylinder block 3 between the drive disc 7 and the valve plate 8. The center shaft 10 has a spherical portion 10A formed at one end thereof, and the spherical portion 10A is formed on the drive disc 7. It is swingably supported around O ₁ as the tilt center. On the other hand, the other end of the center shaft 10 protruding through the center of the cylinder block 3 is slidably inserted into the through hole 8A of the valve plate 8 to perform centering between the cylinder block 3 and the valve plate 8. Has been.

Reference numeral 11 is a tilting mechanism for tilting the valve plate 8 along the tilting sliding surface 9, and the tilting mechanism 11 is provided in the head casing 1B and has oil passage holes 12A, 12B at both axial ends. The chamber 12 and the cylinder chamber 12 are slidably inserted into the chamber 12.
Servo piston 14 defining axially opposite sides in hydraulic chambers 13A and 13B and a peripheral body portion of servo piston 14 are inserted and spherical tip portion 15A is swingably inserted into through hole 8A of valve plate 8. The rocking pin 15 is provided, and the valve plate 8 and the cylinder block 3 are integrally tilted by supplying / discharging pressure oil to / from the hydraulic chambers 13A and 13B.

The hydraulic rotary machine according to the prior art has the above-mentioned configuration. Next, the operation of the hydraulic rotary machine used as a hydraulic pump will be described.

First, the tilting mechanism 11 tilts the valve plate 8 together with the cylinder block 3 to the tilting position shown in the figure. Therefore, for example, pressure oil from an auxiliary pump for tilt control is supplied to the hydraulic chamber 13A (13B) on one side of the cylinder chamber 12 to displace the servo piston 14. Then, together with the servo piston 14, a swing pin 15
Is also displaced, and the valve plate 8 is tilted while sliding on the tilt sliding surface 9, so that the cylinder block 3 is also tilted, and its rotation center axis is tilted with respect to the rotation center axis of the rotation shaft 2. Tilt to the maximum rolling side (minimum tilting side), and the state shown in the drawing is obtained.

Next, the drive source such as the engine and the electric motor is rotated to rotate the rotary shaft 2
When the rotary drive is performed, the drive disk 7 of the rotary shaft 2 and each piston 5 inserted in the cylinder 4 of the cylinder block 3
The cylinder block 3 is rotated together with the rotating shaft 2 because the connecting rod 6 is connected between the cylinder block 3 and the cylinder. Then, each piston 5 reciprocates in the cylinder 4 while the cylinder block 3 is rotating. When each piston 5 retreats from the inside of the cylinder 4, it becomes an intake stroke in which hydraulic oil is sucked into the cylinder 4 from the supply / discharge passage through the supply / discharge port, and when the piston 5 enters the cylinder 4, 4 is a discharge stroke in which the hydraulic oil in 4 is pressurized and discharged from the supply / discharge passage via the supply / discharge port.

[Problems to be solved by the invention]

However, in the conventional technology configured as described above, the servo piston 14 configuring the tilting mechanism 11 is provided in the cylinder chamber 12 of the head casing 1B. That is, the servo piston 14 is arranged outside the sliding radius of the valve plate 8 and tilts the valve plate 8 via the swing pin 15.

Therefore, the servo piston 14 and the operating point of the valve plate 8 are separated by the distance l shown in FIG.
An operating moment having a magnitude of the product of the tilting operation force acts on the sliding surface between the servo piston 14 and the cylinder chamber 12 as a moment load. As a result, there is a problem that not only the performance is deteriorated due to wear of the servo piston 14 and the cylinder chamber 12, but also the tilting function is disabled due to a galling phenomenon, a seizure phenomenon, and the like.

On the other hand, since the tilting mechanism 11 is provided in the head casing 1B, the axial dimension of the casing 1 as a whole becomes long, and when the hydraulic rotary machine is used as a traveling hydraulic motor of a construction machine, the shoe width of the crawler belt is reduced. There is a problem that the so-called “in-shoe” type cannot be realized because it projects outward.

The present invention has been made in view of the above problems of the prior art, and by arranging the servo piston on the peripheral wall portion of the casing, the operating moment is minimized and the axial dimension of the casing is reduced. It is an object of the present invention to provide a variable capacity oblique shaft type hydraulic rotating machine capable of performing the above operation.

[Means for solving problems]

In order to solve the above-mentioned problems, a variable capacity oblique shaft type hydraulic rotating machine according to the present invention comprises a casing having a cylindrical casing body and a head casing that closes the opening side of the casing body, and a casing of the casing. A rotation shaft rotatably supported in the main body, a cylinder block provided in the casing and rotating together with the rotation shaft,
A valve plate having one end face slidingly contacting the cylinder block and the other end face slidably slidingly contacting a tilting sliding face formed on the inner peripheral side of the head casing of the casing; A tilting mechanism provided on the head casing is provided for tilting the plate.

The feature of the configuration adopted by the present invention is that the tilting mechanism is disposed on the minimum tilting side of the valve plate and is disposed on the peripheral wall portion of the head casing of the casing substantially flush with the valve plate. And a servo piston in which the piston portion is slidably fitted in the cylinder chamber of the cylinder portion, and the tip of the piston rod portion extends into the casing.
In order to connect the servo piston and the valve plate, the valve plate is located on the minimum tilt side of the valve plate and disposed in the space inside the casing. One end side of the valve is rotatably connected to the tip of the piston rod of the servo piston. A link mechanism rotatably connected to the valve plate on the other end side, and the cylinder portion of the tilting mechanism, the servo piston, and the link mechanism and the valve plate are located on substantially the same plane. It is in.

[Action]

When the servo piston is linearly moved in the cylinder portion in the direction orthogonal to the rotation axis, the linear movement of the servo piston is transmitted to the valve plate via the link mechanism, and the arc motion of the valve plate can be smoothly performed. . At this time, the cylinder portion is located on the minimum tilting side of the valve plate and is disposed on the peripheral wall portion of the head casing of the casing on substantially the same plane as the valve plate, and is slidably fitted into the cylinder portion. Since the servo piston and the link mechanism are also located on the same plane as the valve plate, a stable tilting mechanism can be achieved by making the operating moment when the servo piston moves linearly substantially zero. In addition, the axial dimension of the casing can be shortened, the size and weight of the casing can be reduced, and the dead space in the casing can be effectively used.

〔Example〕

Hereinafter, an embodiment of the present invention will be described in detail with reference to FIGS. 1 to 5. The same components as those of the above-described conventional technique are designated by the same reference numerals, and the description thereof will be omitted.

1 and 2 show a first embodiment of the present invention.

In the drawings, 21 is a casing according to the present embodiment, which is formed of a cylindrical casing body 21A and a head casing 21B for closing the head side of the casing body 21A as in the prior art. However, since the tilting mechanism 24, which will be described later, is provided on the peripheral wall portion of the head casing 21B, the axial dimension of the casing 21 is shorter than that of the conventional casing 1.

Reference numeral 22 denotes a valve plate used in this embodiment, and like the valve plate 8 of the prior art, the valve plate 22 has one end face slidingly contacting the cylinder block 3 and the other end face tilting and sliding face of the head casing 21B. 9, a bottomed insertion hole 22A into which the tip end of the center shaft 10 is inserted is formed in the center of the valve plate 22, and supply / discharge ports 22B, 22C which communicate with each cylinder 4 intermittently are formed. Has been formed. However, the valve plate 22 of the present embodiment is formed with bearing holes 23, 23 (however, one is not shown) into which the connecting pin 31 described later is inserted at the center in the thickness direction and the height direction on both end faces thereof. It is different (see Fig. 2).

Reference numeral 24 denotes the tilting mechanism of the present embodiment. The tilting mechanism 24 is the tilting minimum side (upper side in FIG. 1) of the valve plate 22 and is on the same plane H-H as the valve plate 22. Is located and the axis A-A of the rotary shaft 2
Head casing so that it protrudes in a direction almost orthogonal to
A cylinder portion 25 protruding from the peripheral wall portion of 21B, a cylinder chamber 26 formed in the cylinder portion 25, through which oil pressure is supplied and discharged through oil passage holes 26A, 26B, and the cylinder chamber 26. A servo piston 27 including a piston portion 27A slidably inserted and a piston rod portion 27B extending into the casing 21 through a piston insertion hole 28 of a head casing 21B, and one end side of the servo piston 27 via a pin 29. 27 piston rod
27B is rotatably connected to the tip, and the other end of the link 30 is branched into a semicircular bifurcated portion so as to straddle the valve plate 22, and the link 30 is provided at the bifurcated tip of the link 30 Composed of connecting pins 31, 31 rotatably inserted into the bearing holes 23, 23,
The pin 29, the link 30, the connecting pin 31, etc. constitute the link mechanism of this embodiment.

Thus, the cylinder portion 25, the servo piston 27, and the link 30, which constitute the tilting mechanism 24, are located on the tilting minimum side of the valve plate 22 and form a plane H-H that is substantially the same as the valve plate 22. The servo piston 27 is arranged on the peripheral wall portion of the casing 21B and supplies and discharges the pressure oil for tilt control from the oil passage holes 26A and 26B, so that the servo piston 27 slides in a direction substantially orthogonal to the axis AA of the rotary shaft 2. The valve plate 22 and the cylinder block 3 are displaced and integrally tilt-controlled via the link 30.

The present embodiment is configured in this way, and its operation will be described next.

First, in order to tilt the valve plate 22 together with the cylinder block 3 by the tilting mechanism 24, pressure oil is supplied to the cylinder chamber 26 from the oil holes 26A (26B), and the servo piston 27 is displaced as a linear motion. As a result, the valve plate 22 slides on the tilt slide surface 9 via the link 30 and the connecting pin 31 connected to the piston rod portion 27B of the servo piston 27, and as a result, the cylinder block 3 also moves. Tilting, and its rotation center axis is the tilt maximum side (tilt minimum side) with respect to the axis AA of the rotary shaft 2.
And the state shown in FIG. 1 is obtained.

At this time, while the servo piston 27 moves linearly,
The valve plate 22 is guided by the tilt sliding surface 9 and moves in an arc, but the servo piston 27 and the link 30 are rotatably connected via a pin 29, and the link 30 and the valve plate 22 are connected by a connecting pin 31. Since it is rotatably connected via, it is possible to smoothly convert the linear motion and the arc motion.

In addition, in order to operate as a hydraulic pump with the cylinder block 3 tilted together with the valve plate 22 as described above,
As in the prior art, the cylinder block 3 is rotated together with the rotary shaft 2 to cause the piston 5 to reciprocate in the cylinder 4, sucking hydraulic oil from the intake / exhaust port 22B (22C) of the valve plate 22 in the intake stroke and in the discharge stroke. The pressure oil is discharged from the supply / discharge port 22C (22B).

Thus, in the present embodiment, the cylinder portion that constitutes the tilting mechanism 24.
Since 25 is formed on the peripheral wall portion of the head casing 21B on the tilting minimum side and the servo piston 27 is slidably provided on the cylinder portion 25, the linear movement of the servo piston 27 is immediately performed via the link 30. It can be transmitted as an arc motion of the valve plate 22. As a result, since the moment load acting on the servo piston 27 can be almost zero, the servo piston 27 can smoothly slide in the cylinder chamber 26,
The tilting mechanism 24 can be operated stably. Particularly, by arranging the cylinder portion 25, the servo piston 27, the link 30, and the valve plate 22 on substantially the same plane H-H as shown in the drawing, the above effect is further enhanced.

Further, since the tilting mechanism 24 is provided on the peripheral wall portion of the head casing 21B, the axial dimension of the entire casing 21 is larger than that of the tilting mechanism 11 according to the related art provided on the axial end surface of the head casing 1B. Can be shortened.

Further, the pin 29, the link 30, the connecting pin 31, etc., which constitute the link mechanism, can be provided in the cylinder block tilting space in the casing 21, which is originally a dead space, so that the dead space can be effectively used and the casing can be effectively used. It is possible to reduce the weight of 21 and make it compact.

Next, FIGS. 3 and 4 show a second embodiment of the present invention.
The valve plate 41 of this embodiment has a bottomed insertion hole 41A and a supply / discharge port 4
1B and 41C are formed, and the connecting portion 41D is provided on the upper surface side.
Is projected. Then, the tip of the piston rod portion 27B of the servo piston 27 and the connecting portion 41D are connected to each other by a pair of connecting plates 4
2, 42, a pin 43 for rotatably attaching the upper end of the connecting plate 42 to the piston rod portion 27B, and a lower end of the connecting plate 42 for connecting portions.
It is configured to be connected to another pin 44 that is rotatably attached to 41D. Therefore, the link mechanism of this embodiment is composed of the connecting plate 42, the pins 43, 44 and the like.

Although the present embodiment is configured in this way, there is no difference from the first embodiment except that the structure of the link mechanism is different, and therefore the description of its operation is omitted.

Furthermore, FIG. 5 shows a third embodiment of the present invention.

In the drawings, reference numeral 51 denotes a casing according to this embodiment, which is formed of a cylindrical casing body 51A and a head casing 51B for closing the head side of the casing body 51A as in the first embodiment. The tilting sliding surface 9 of the head casing 51B is provided with a valve plate 52 having the same shape as that of the first embodiment, and the connecting pins 62 described later are inserted into both end surfaces of the valve plate 52. Bearing holes 53, 53 (shown as reference numeral (53) in FIG. 2) are formed.

Reference numeral 54 denotes a tilting mechanism used in this embodiment. The tilting mechanism 54 is the tilting minimum side (upper side in FIG. 5) of the valve plate 52, which is the head casing, as in the first embodiment. A cylinder portion 55 protruding from the peripheral wall portion of 51B as described later, and the cylinder portion 55.
A cylinder chamber 56 that is formed inside 55 and through which oil is supplied and discharged via oil passage holes 56A and 56B, a piston portion 57A slidably inserted into the cylinder chamber 56, and a piston of the head casing 51B. A servo piston 57 including a piston rod portion 57B extending into the casing 51 through an insertion hole 58, and a piston rod portion 57 of the servo piston 57 having a pin 59 at one end side thereof.
A link 60 that is rotatably connected to the tip of B and has a second end branched into a semicircular bifurcated portion so as to straddle the valve plate 52, and the link 60.
The connecting pin 61, 61 is provided at the tip of the bifurcated portion of the valve 60 and is rotatably inserted into the bearing hole 53, 53 of the valve plate 52. The pin 59, the link 60, the connecting pin 61, etc. It constitutes the link mechanism of the embodiment.

Here, in the tilting mechanism 54 of the present embodiment, the cylinder portion 55 is formed on the peripheral wall portion of the head casing 51B on the tilting minimum side of the valve plate 52 as in the first embodiment, and the valve plate 52 when although located on substantially the same plane H'-H ', when the valve plate 52 is in the intermediate position O ₁ -D the maximum tilting position O ₁ -B and the minimum tilting position O ₁ -C (FIG. 5 shows this state), the center position O ₂ of the connecting pin 61 described above is used as a contact point, and the tilt center O ₁ of the cylinder block 3 is used as the center. Arc with radius r Tangential line F-F direction (in the case of this embodiment, the above-mentioned plane H-H)
And the tangent line F-F are substantially in the same direction).

Thus, the servo piston 57 slidably provided on the cylinder portion 55 is also arranged on the peripheral wall portion of the head casing 51B so as to operate in the tangential line FF direction similarly to the cylinder portion 55, and the tangent line F The valve plate 52 and the cylinder block 3 are tilted and controlled through the link 60 by sliding displacement in the −F direction.

Although the present embodiment is configured in this way, the operation of the hydraulic rotary machine, the operation of the tilting mechanism 54, etc. are the same as those of the first embodiment, so description thereof will be omitted.

However, in the first embodiment, the servo piston 27 has the rotating shaft 2
Of the valve plate 22 and the cylinder block 3 are arranged so as to slide in a direction substantially perpendicular to the axis A-
It is arranged in a state of being inclined at a predetermined angle with respect to A. As a result, when a tilting actuation force indicated by f _{0 in} FIG. 1 is generated in order to tilt the valve plate 22 and the cylinder block 3 by the servo piston 27, the tilting actuation force f ₀ is applied to the valve plate 22.
Acting as component forces f ₁ and f ₂ . Here, the component force f ₁ acts as a tensile force of the valve plate 22, while the component force f ₂ acts as a separating force of the valve plate 22. Therefore, since the opening force f ₂ is opposed, it is necessary to increase the pressing force of the spring or the like provided in the center shaft 10, and it is necessary to use a spring having a strong spring force.

However, in the present embodiment, when the valve plate 52 is at the intermediate position O ₁ -D in the tilt range, the servo piston 57 uses the center position O ₂ of the connecting pin 61 as a contact point and makes an arc. Since it is arranged so as to be slidably displaced in the tangent line F-F direction, when the tilting operation force f ₀ is generated in the servo piston 57, most of it acts as a tensile force of the valve plate 52. For this reason, there is no risk of generating a separating force on the valve plate 52 during tilting, and there is no need for spring means having a large pressing force as in the first embodiment.

The link mechanism is not limited to the first and second embodiments, and the linear movement of the servo piston 27 (57) is not limited to the valve plate 22 (5
2) If it can be converted into circular motion,
Other configurations may be used.

Further, the servo piston 27 (57) may be provided on the tilt minimum side peripheral wall portion of the casing 21 (51), and it is not necessary to position it on the substantially same plane H-H as the valve plate 22 (52) as in the embodiment. Absent.

Further, the cylinder portion 25 (55) is connected to the head casing 21B (5
It is not limited to one integrally formed with 1B), and a separate cylinder part may be attached to the head casing 21B (51B).

[Effect of device]

The variable displacement oblique shaft type hydraulic rotating machine according to the present invention is as described in detail above. The cylinder part and the servo piston forming the tilting mechanism are the head casing peripheral wall part of the casing and the tilting of the valve plate. A link mechanism for connecting the servo piston and the valve plate to the minimum rotation side, and a link mechanism for connecting the servo piston and the valve plate to the cylinder inner space on the minimum tilt side of the valve plate;
Since the servo piston and the link mechanism and the valve plate are positioned on substantially the same plane, it is possible to obtain a tilting mechanism that is stable in operation and has a small moment load, and also shortens the axial dimension of the casing. In addition, since the link mechanism can be arranged by effectively utilizing the dead space in the cylinder brick tilting space, it is possible to reduce the weight and size of the hydraulic rotary machine as a whole. Play.

[Brief description of drawings]

1 and 2 relate to a first embodiment of the present invention, FIG. 1 is a longitudinal sectional view of an oblique shaft type hydraulic rotary machine according to this embodiment, and FIG. 2 shows a link mechanism and a valve plate. FIG. 1 is an enlarged view of an essential part of a partially cutaway view from the left side of FIG. 1, FIGS. 3 and 4 relate to a second embodiment of the present invention, and FIG. 3 shows a link mechanism and a valve plate. FIG. 4 is a right side view of FIG. 3, and FIG. 5 is a longitudinal sectional view showing an oblique shaft type hydraulic rotary machine according to a third embodiment of the present invention. FIG. 6 is a vertical cross-sectional view showing a conventional oblique shaft type hydraulic rotating machine. 2 ... Rotary axis, 3 ... Cylinder block, 9 ... Tilting sliding surface,
21,51 ... Casing, 22,41,52 ... Valve plate, 24,54 ... Tilt mechanism, 25,55 ... Cylinder part, 26,56 ... Cylinder chamber, 27,57 ...
Servo piston, 29,43,44,59 ... pin, 30,60 ... link,
31,61… Connecting pin, 42… Connecting plate.

Claims (3)

[Scope of utility model registration request] 1. A casing comprising a tubular casing body and a head casing for closing the opening side of the casing body, a rotary shaft rotatably supported in the casing body of the casing, and a casing provided in the casing. ,
The cylinder block rotating together with the rotary shaft has one end surface slidingly contacting the cylinder block, and the other end surface slidably slidingly contacting a tilting sliding surface formed on the inner peripheral side of the head casing of the casing. In a variable displacement oblique shaft type hydraulic rotating machine comprising a valve plate and a tilting mechanism provided in the head casing for tilting the valve plate together with the cylinder block, the tilting mechanism is A cylinder portion disposed on the minimum tilting side of the valve plate on the peripheral wall portion of the head casing of the casing and substantially flush with the valve plate, and a piston portion sliding in a cylinder chamber of the cylinder portion. A servo piston that is movably inserted and has a tip of a piston rod portion extending into the casing, and is located on the minimum tilting side of the valve plate for connecting the servo piston and the valve plate. The tilt mechanism, the link mechanism being disposed in the inner space, one end side being rotatably connected to the tip of the piston rod portion of the servo piston, and the other end side being rotatably connected to the valve plate. The variable capacity oblique shaft type hydraulic rotating machine in which the cylinder portion, the servo piston, the link mechanism, and the valve plate are located on substantially the same plane. 2. The variable capacity oblique shaft type hydraulic rotation according to claim 1, wherein the servo piston is arranged so as to operate in a direction substantially orthogonal to the axis of the rotary shaft. Machine. 3. The tilting of the cylinder block, wherein the servo piston uses the connecting pin position of a link mechanism provided on the end face of the valve plate as a contact when the valve plate is at a substantially intermediate position of the tilting range. Claim for utility model arranged so as to operate in a tangential direction of an arc centered on the center (1)
Variable capacity oblique shaft type hydraulic rotating machine described in the paragraph.