JPH0441257Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an improvement of a variable capacity oblique shaft type hydraulic rotating machine used as a hydraulic pump or hydraulic motor used in civil engineering/construction machinery and other general machinery.

[Conventional technology]

FIG. 6 and FIG. 7 show a hydraulic pump as a variable displacement oblique shaft type hydraulic rotating machine according to the prior art.

In the figure, reference numeral 1 denotes a cylindrical casing, and the casing 1 consists of a substantially cylindrical casing body 1A with one end serving as a bearing portion, and a head casing 1B that closes the other end of the casing body 1A. Reference numeral 2 designates a rotary shaft that rotatably protrudes into the casing body 1A, and 3 a cylinder block that is located within the casing body 1A and rotates together with the rotary shaft 2. A plurality of cylinders 4 are bored. A piston 5 is slidably provided within 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,
The spherical portion 6A is swingably supported by a drive disk 7 formed at the tip of the rotating shaft 2.

Reference numeral 8 indicates a valve plate, and one end surface of the valve plate 8 is in sliding contact with the cylinder block 3, and the other end surface is slidable on a concave arc-shaped tilting sliding surface 9 formed on the head casing 1B. It is in sliding contact with the
At the center of the valve plate 8 is a center shaft 10 which will be described later.
Through-holes 8A are formed into which the respective tips of the swing pins 15 are inserted from both sides. and,
A pair of supply and discharge ports (not shown) are bored in the valve plate 8 and communicate intermittently with each cylinder 4 as the cylinder block 3 rotates. Regardless of the case, it communicates with a supply/discharge passage (not shown) that opens on the tilting sliding surface 9 of the head casing 1B.

Reference numeral 10 denotes a center shaft for supporting the cylinder block 3 between the drive disk 7 and the valve plate 8. The center shaft 10 has a spherical portion 10A formed at one end thereof. It is swingably supported at the center of the shaft. On the other hand, the other end of the center shaft 10 that protrudes through the center of the cylinder block 3 is a valve plate 8.
It is slidably inserted into the through hole 8A of the cylinder block 3 and the valve plate 8, and centering between the cylinder block 3 and the valve plate 8 is performed.

Reference numeral 11 denotes a tilting mechanism for tilting the valve plate 8 along the tilting sliding surface 9. The tilting mechanism 11 is bored in the head casing 1B, and has oil through holes 12A,
12B; a cylinder chamber 12 slidably inserted into the cylinder chamber 12;
The servo piston 14 defines hydraulic pressure chambers 13A and 13B on both axial sides of
The swing pin 15 is swingably inserted into the through hole 8A of
The hydraulic pressure chambers 13A,
Auxiliary pump 1 that supplies pressure oil for tilting into 13B
7, it is driven to tilt and rotate. In addition, 18 in the figure
is a tank connected to piping 16B.

19 is a control unit provided outside the head casing 1B for controlling the tilting mechanism 11;
The control section 19 controls the auxiliary pump 17 and the cylinder chamber 12.
A throttle switching valve 20 is provided between the pipes 16A and 16B, and is capable of feedback control of the pilot pressure of pressure oil from the auxiliary pump 17 using the sleeve 20A. It is composed of an operating lever 21 that operates. A space between the sleeve 20A and the servo piston 14 is fixed to the servo piston 14, and a long hole 1C is formed in the head casing 1B.
The sleeve 20A controls the pilot pressure of the pressure oil supplied from the auxiliary pump 17 to each hydraulic pressure chamber 13A, 13B as the servo piston 14 moves. I'm starting to do that.

The variable capacity oblique shaft type hydraulic rotating machine according to the prior art has the above-described configuration.Next, the operation of the hydraulic rotating machine will be explained when the hydraulic rotating machine is used as a hydraulic pump.

First, the cylinder block 3 is moved by the tilting mechanism 11.
At the same time, the valve plate 8 is tilted to the illustrated tilting position.
Therefore, the control lever 21 of the control unit 19 is operated to switch the throttle switching valve 20, and the pressure oil from the auxiliary pump 17 is transferred to the hydraulic pressure chamber 13A on one side of the cylinder chamber 12,
13B to displace the servo piston 14. Then, the swing pin 15 is also displaced together with the servo piston 14, and the valve plate 8 is tilted while sliding on the tilting sliding surface 9. As a result, the cylinder block 3 is also tilted, and its center axis of rotation is It is tilted and rotated with respect to the rotation center axis of the rotating shaft 2, and the state shown in the figure is obtained.

Next, a drive source such as an engine or electric motor is rotated,
When the rotary shaft 2 is driven to rotate, the drive disk 7 of the rotary shaft 2 and each piston 5 inserted into the cylinder 4 of the cylinder block 3 are connected by a connecting rod 6. 3 is rotated. Then,
While the cylinder block 3 is rotating, each piston 5 reciprocates within the cylinder 4. And each piston 5
When the piston 5 faces the cylinder 4 from within the cylinder 4, it is a suction 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, the hydraulic oil in the cylinder 4 is sucked into the cylinder 4. pressurize,
This is a discharge stroke in which the fluid is discharged from the supply and discharge passage through the supply and discharge port.

During the operation of the hydraulic rotary machine described above, the valve plate 8
The amount of tilting is controlled by the throttle switching valve 2 via a feedback pin 22 that is integrally provided on the other side of the swing pin 15.
0 sleeve 20A. Auxiliary pump 1
The pilot pressure of the pressure oil from 7 to each hydraulic pressure chamber 13A, 13B is feedback-controlled by the sleeve 20A, and the pressure oil is supplied to each hydraulic chamber 13A, 13B in accordance with the amount of tilting of the valve plate 8. flow rate is controlled.

[Problem that the invention attempts to solve]

In the prior art configured as described above, the valve plate 8 sliding on the tilting sliding surface 9 moves in an arc, whereas the servo piston 14 moves vertically in a straight line within the cylinder chamber 12. Do exercise. Therefore, the swing pin 1 fixed to the servo piston 14
The spherical tip 15A of No. 5 performs a sliding operation within the through hole 8A of the valve plate 8, but the swing pin 15 slides inside the through hole 8A of the valve plate 8.
In order to be able to slide smoothly within A, the swing pin 15 must be
It is necessary to provide a slight gap between the tip portion 15A and the through hole 8A. Then, as the hydraulic rotary machine is operated for a long period of time, the gap becomes enlarged due to wear caused by the sliding action.

Thus, an error occurs between the actual tilting position of the valve plate 8 for the gap and the position of the valve plate 8 detected by the feedback pin 22 via the swing pin 15, and the throttle switching valve 20 The disadvantages are that the responsiveness of the sleeve 20A is poor, the follow-up accuracy of the throttle switching valve 20 is poor, and the feedback control performance is significantly reduced.

Further, a feedback pin 22 that transmits the amount of tilting A ₀ of the valve plate 8 to the control unit 19 is provided directly on the servo piston 14 that tilts the valve plate 8.
Since the amount of displacement of the servo piston 14 and the amount of displacement of the feedback pin 22 are the same, there is a drawback that the control section 19 cannot be provided on the casing body 1A side and cannot be made compact.

The present invention was developed in view of the problems of the prior art described above, and instead of indirectly detecting the tilting position of the valve plate from the tilting mechanism, the present invention proportionally reduces the tilting amount from the valve plate. A variable-capacity oblique-shaft hydraulic system that can directly detect the current state, improve response performance such as response and tracking accuracy of the control unit, and reduce the overall size of the device. The purpose is to provide rotating machines.

[Means for solving problems]

In order to solve the above problems, the features of the means adopted by the present invention include a support pin located on the center line of tilting of the cylinder block and provided in the body of the casing, and one end connected to the support pin. a rocking lever whose other end is connected to the valve plate, and swings together with the valve plate around the support pin; an output pin provided on a lever attached to a pin and connected to the control unit,
By setting the length between the support pin and the output pin shorter than the length of the swing lever, feedback is provided to the control unit in a state where the amount of tilting of the valve plate is proportionally reduced. This is because it was configured as follows.

[Effect]

In this way, by providing the swinging lever between the support pin and the valve plate, the amount of tilting of the valve plate can be directly detected as the amount of swinging of the swinging lever.
Moreover, since the output pin is provided on the swing lever, or on the support pin or a lever attached to it, the length of the swing lever from the tilting center line and the length to the position of the output pin are different. As a ratio, the amount of tilting of the valve plate can be proportionally reduced and output to the control unit.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings. Note that the same reference numerals are given to the same components as those of the prior art described above, and the explanation thereof will be omitted.

1 to 3 show a first embodiment of the present invention. In the figure, 31 is the casing of this embodiment, and the casing 31 is formed from a cylindrical casing main body 31A and a head casing 31B that closes the other end side of the casing main body 31A. A long hole 31C is bored in the center of the side of the body in the circumferential direction.

32 protrudes from the body of the servo piston 14, and connects the spherical tip 32A to the through hole 8A of the valve plate 8.
The servo piston 14 has a swing pin 15 slidably inserted into the servo piston 14.
A feedback pin 22 integrally provided with the head casing 31B is not provided, and therefore, an elongated hole 1C as shown in FIG. 6 is not formed in the head casing 31B.

Reference numeral 33 denotes a control section provided on the outer side of the circumference of the casing body 31A near the head casing 31B in order to control the tilting mechanism 11, and the control section 33 is connected to the auxiliary pump 17 as in the prior art. Throttle switching valve 3 located between each hydraulic pressure chamber 13A, 13B and interposed in piping 16A, 16B
4, and a sleeve 3 provided on the throttle switching valve 34.
4A, and an operating lever 35 for switching the throttle switching valve 34.

36 is the tilting center line X-X of the cylinder block 3
A support pin 37 located above, that is, above the center of the spherical portion 6A of the connecting rod 6 and protruding into the casing body 31A, is located on the same side as the support pin 36 and spaced a distance ₀ from the support pin 36. A detection pin 38 is a swing lever provided between the support pin 36 and the detection pin 37, and the swing lever 38 rotates the valve around the support pin 36. It is designed to be able to swing together with the plate 8. Reference numeral 39 denotes an output pin that is swingably inserted into the elongated hole 31C of the casing main body 31A. One end of the output pin 39 is connected to the sleeve 34A of the throttle switching valve 34, and the other end is connected to the sleeve 34A of the throttle switching valve 34, and the other end is connected to the Tilt center line X-
It is connected at a distance of ₁ from X. and,
In this embodiment, a feedback mechanism 40 that transmits the amount of tilting of the valve plate 8 to the control section 33 is configured by a support pin, a detection pin 37, a swing lever 38, and an output pin 39.

This embodiment is constructed as described above, and the operation itself as a variable capacity hydraulic pump is the same as that of the prior art described above.

However, in order to change the discharge capacity of the hydraulic pump, the control lever 35 is operated to switch the throttle switching valve 34.
from the auxiliary pump 17 to each hydraulic pressure chamber 13A,
When the pilot pressure of the pressure oil supplied to the valve 13B is changed, the servo piston 14 is displaced within the cylinder chamber 12. As a result, the valve plate 8 is tilted and slid by the swing pin 32, which is displaced together with the servo piston 14. It tilts while sliding on the moving surface 9.

The detection pin 37 together with the valve plate 8 that tilts as described above.
is also displaced, and the swinging lever 38 is tilted at the same angle as the valve plate 8 about the tilting center line XX. Then, the output pin 39 connected to the swing lever 38 moves by an amount of movement A ₁ that is reduced to a ratio of _1/0 to the amount of tilting A ₀ of the valve plate ₈ , and the sleeve of the throttle switching valve 34 moves. 34A, and each hydraulic pressure chamber 13A, 1 is supplied from the auxiliary pump 17.
Feedback controls the pilot pressure of pressure oil supplied to 3B.

As described in detail above, according to this embodiment, the valve plate 8
The tilting position of the valve plate 8 is directly detected by the detection pin 37 protruding from the valve plate 8.
There is no deviation in the follow-up control of the control unit 33 with respect to the tilting, and the control performance of the control unit 33, such as responsiveness, follow-up accuracy, and operational feel, is improved.

Further, the tilting amount A ₀ of the valve plate 8 is the distance ₀ between the tilting center line XX of the support pin 36 and the detection pin 37.
and the distance between the support pin 36 and the output pin 39
By appropriately setting the ratio with ₁ , the amount of tilting A ₀
Since the signal can be transmitted to the control unit 33 with a reduced number, the degree of freedom in designing the control unit 33 itself increases, and it becomes possible to reduce the size of the control unit 33 itself.

Furthermore, in this embodiment, the control section 33 is described as being provided on the outside of the circumference of the casing main body 31A, but since the control section 33 is configured separately from the casing 31, the feedback mechanism 40 can be configured in various ways. By changing the design, it can be mounted in any position and direction such as on the upper side of the circumferential body of the casing 31, increasing the degree of freedom in designing the entire hydraulic rotating machine. Moreover, although the diagonal shaft type hydraulic rotating machine had the disadvantage of being long in the axial direction, this axial length can be shortened, and the entire hydraulic rotating machine can be made smaller. .

Next, a second embodiment of the present invention will be described based on FIG. 4.

In the figure, 41 is the casing of this example,
The casing 41 has a cylindrical casing body 41.
A and a head casing 41B that closes one end of the casing body 41A, and a large diameter support pin 42 is rotatable on the casing body 41A and is located on the tilting center line XX of the cylinder block. is inserted into. 43 is a detection pin located on the same side as the support pin 42 and protruding from the side surface 8B of the valve plate 8; an oil lever 44 is installed between the detection pin 43 and the support pin 42; The swing lever 44 can swing together with the valve plate 8 about the support pin 42.

Reference numeral 45 denotes an output pin that is offset from the axis of the support pin 42 by a distance ₂ toward the valve plate 8 and is implanted on the end surface of the support pin 42. It is connected.
The support pin 42, the detection pin 43, the swing lever 44, and the output pin 45 constitute a feedback mechanism 46 of this embodiment.

Reference numeral 47 denotes a control section provided at the center of the side outer surface of the casing main body 41A, and the control section 47 is equipped with a throttle switching valve having a sleeve and an operation lever (none of which are shown) as in the first embodiment. The control section 47 has a support pin 42 and an output pin 45.
is now inserted.

This embodiment is constructed as described above, and the valve plate 8
The amount of tilting is detected as the rotation angle of the support pin 42 via the detection pin 43 and the swing lever 44. The output pin 45, which is eccentrically provided to the support pin 42 by a _{distance 2} , rotates with a movement amount _A2 that is reduced to a ratio of _2/0 to the tilting amount _A0 of the valve plate 8, and the aperture is Activate the switching valve sleeve.

Therefore, also in this embodiment, the amount of tilting of the valve plate 8
A ₀ can be accurately transmitted to the control unit 47, and the auxiliary pump (see Fig. 3) can transmit the information to each hydraulic pressure chamber 13A, 1.
The pilot pressure of the pressure oil supplied to 3B can be feedback-controlled.

Further, according to the present embodiment, the output pin 39 is attached to the circumference of the casing body 31A as in the first embodiment.
Since there is no need to provide a long hole 31C for insertion, the strength of the casing body 41A can be improved,
Further, it is possible to eliminate the need for oil leakage countermeasures.

In the first embodiment, the output pin 39 was described as being provided on the swing lever 38, but as shown in FIG. lever 5
1 and attach the output pin 3 to the lever 51.
An output pin 39' may be provided instead of 9. With this configuration, the elongated hole 31C of the casing main body 31A can be eliminated as in the second embodiment.

[Effect of idea]

Since the present invention is constructed as described above in detail, the following effects can be achieved.

A support pin is provided in the casing, a swing lever is provided between the support pin and the valve plate, an output pin is provided on the swing lever, the support pin, or a lever attached to the support pin, and from the output pin Since the configuration is such that the amount of tilting of the valve plate is derived, the amount of tilting of the valve plate can be directly detected from the valve plate and fed back to the control unit, making it possible to accurately detect the amount of tilting. , control performance can be improved.

Since the amount of tilting of the valve plate is proportionally reduced by the ratio of the length of the swing lever and the length from the support pin to the output pin and transmitted to the control unit, the control unit can be made compact. This also increases the degree of freedom in designing the control section.

In relation to the above item, since feedback can be sent from the output pin to the control unit while the amount of tilting of the valve plate is proportionally reduced, it is possible to compare the amount of movement of the output pin with the amount of tilting of the valve plate. This allows the casing and control unit to be made smaller.

Since the output pin can be provided on the peripheral wall of the casing, the control section can also be installed at any desired position, including the side wall of the casing, providing greater freedom in designing the entire oblique shaft hydraulic rotating machine.

For the same reason as above, the axial length of the diagonal shaft hydraulic rotating machine can be shortened, and the disadvantage that the conventional variable capacity diagonal shaft hydraulic rotating machine is long in the axial direction can be solved. can.

[Brief explanation of drawings]

1 to 3 show a first embodiment of the present invention, FIG. 1 is a longitudinal cross-sectional view of a diagonal shaft type hydraulic rotating machine according to the present embodiment, and FIG. 2 is a - arrow in FIG. 3 is a circuit diagram showing a tilting mechanism control circuit, FIG. 4 is a partially enlarged sectional view of an oblique shaft type hydraulic rotating machine according to a second embodiment of the present invention, and FIG. 5 is a circuit diagram showing a tilting mechanism control circuit. 6 and 7 are sectional views of essential parts showing a modification of the first embodiment, and FIG. 6 is a longitudinal sectional view of a diagonal shaft type hydraulic rotating machine according to the prior art, and FIG. FIG. 2 is a circuit diagram showing a tilting mechanism control circuit. 2...Rotating shaft, 3...Cylinder block, 4...
... Cylinder, 5 ... Piston, 6 ... Connecting rod, 7 ... Drive disk, 8 ... Valve plate, 9 ... Tilting sliding surface, 11 ... Tilting mechanism, 3
1, 41...Casing, 31B, 41B...Head casing, 33, 47...Control unit, 36,
42... Support pin, 38, 44... Swing lever,
39, 45, 39'...Output pin, 40, 46...
...Feedback mechanism, 51...Lever.

Claims (1)

[Scope of utility model registration request] A cylindrical casing whose end face is closed by a head casing, a rotary shaft rotatably protruding into the casing and whose tip within the casing serves as a drive disk; A cylinder block that rotates with the rotating shaft, a plurality of cylinders bored in the axial direction of the cylinder block, a piston that is slidably provided in each cylinder, and a piston that is attached to each piston and has a spherical tip. A connecting rod is swingably supported on the drive disk of the rotating shaft as a part, and one end surface slides on the cylinder block and the other end surface slides on the tilting sliding surface of the head casing. a valve plate having a pair of supply/discharge ports movably in sliding contact and intermittently communicating with each cylinder while the cylinder block rotates;
In order to tilt the valve plate together with the cylinder block, a tilting mechanism having a servo piston is provided in the head casing, and in order to operate the servo piston of the tilting mechanism, a tilting pressure is applied to the tilting mechanism. In a variable capacity oblique shaft type hydraulic rotating machine comprising a control section for supplying and discharging oil, a support pin located on the tilting center line of the cylinder block and provided on the circumference of the casing; connected to the pin and the other end connected to the valve plate;
a swinging lever that swings together with the tilting of the valve plate around the support pin; and the swinging lever;
or an output pin provided on the support pin or a lever attached to the support pin and connected to the control unit, wherein the length between the support pin and the output pin is longer than the length of the swing lever. 1. A variable capacity oblique shaft type hydraulic rotating machine, characterized in that the variable capacity oblique shaft type hydraulic rotating machine is configured to provide feedback to the control unit in a state in which the amount of tilting of the valve plate is proportionally reduced by setting the valve plate to a shorter value.