JPH025762A - Variable type oil-hydraulic motor - Google Patents

Abstract

PURPOSE:To have an oil-hydraulic motor with selectivity from high to low speed and vice versa by furnishing No.1 seat face and No.2 seat face having different angles on the opposite side to the surface contacted by the shoe of a swash board, and by putting either of them in contact with one plane of the casing. CONSTITUTION:A supplying oil path 11, an exhausting oil path 12, and an aux. flow path 13 are provided in a casing 1, which is equipped with a cylinder block 3, swash board 4, and plate 5. Further the casing 1 is equipped with an aux. cylinder 14 in communication with the aux. flow path 13, and in its inside a pushing member P is fitted which is slided by oil pressure in this aux. flow path 13. The pushing member P consists of an aux. plunger 15, at whose tip an aux. shoe 16 is fitted rotatably. No.1 seat face 40 and No.2 seat face 41 are formed on the swash board 4 and controlled by the pushing member P so that either of the seat faces 40, 41 will be in contact with the inner wall 1a of the casing, and thus switching is made from high to low speed and vice versa.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a variable hydraulic motor, and particularly to a variable hydraulic motor with two high and low speeds.
This invention relates to a variable hydraulic motor with variable control.

BACKGROUND ART Conventionally, variable hydraulic motors have been used in devices such as full dozers and shovel dozers that require two speeds of high and low speed running. When using this variable hydraulic motor, the inclination angle of the swash plate is determined by providing a stopper mechanism on the actuator that drives the swash plate, or by bringing the swash plate itself into contact with a stopper member. It was °C.

However, in the former case, the actuator section becomes complicated and the inclination angle needs to be adjusted, making the operation cumbersome. Further, in the latter case, there are similar problems, and the angle of inclination changes during use due to wear of the stopper member, etc., which tends to cause inconveniences such as the vehicle on which it is mounted, such as a bulldozer, to move around a corner.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a new hydraulic motor that has a simple structure, is easy to adjust, and is variable only between two high and low speeds, which is stable without changing the tilt angle of the swash plate during the process. The purpose is to

To achieve this goal, the present invention includes a casing, a rotating shaft pivotally connected to the casing, a cylinder block connected to the rotating shaft, and a plunger end inserted into the cylinder block. The swash plate has a sliding surface portion against which the shoe contacts, and a first seat surface and a second seat surface provided at different angles on the opposite side of the sliding surface portion. In a hydraulic motor that has a seat surface, and the swash plate tilts about the intersection line of the first seat surface and the second seat surface as a fulcrum, either the seat surface of the fiSl or the second seat surface The casing...
It is characterized in that it comes into contact with a flat surface and serves as a stopper.

The present invention will be explained below based on a preferred embodiment shown in one figure.

FIG. 1 shows a circuit diagram when used as a two-speed hydraulic motor A according to the present invention. , and after driving the hydraulic motor A, the return trip E is started.
The oil returns to oil pump C through .

As shown in FIG. 2, this hydraulic motor A has a casing 1, a single rotation shaft 2, a cylinder block 3, a swash plate 4, and a plate 5.

Inside the casing l, there is the cylinder block 3,
A swash plate 4 and a plate 5 are provided, and the casing l itself includes a supply oil passage 11 connected to two-moon shaped (not shown) boats 5a and 5b bored in the plate 5, and a discharge oil passage 11. A passage 12 and an auxiliary oil passage 13 are bored, and the casing l is also provided with an auxiliary cylinder 14 communicating with the auxiliary oil passage 13. A suppressing member P is fitted into the auxiliary cylinder 14 and is slidable by hydraulic pressure applied through the auxiliary oil passage 13. Rotatably attach the auxiliary shoe 16 to the tip of the '! J
It is something that is doing t. In addition, the auxiliary oil passage 13 has a separate route from the oil pump C (see Fig. 1), and a control bag M (see Fig. 1).
(not shown).

On the other hand, the rotating shaft 2, which is connected to the cylinder block 3 by a spline or the like, has a bearing 2 in the center of the casing l.
0.21, and is sealed by a sealing member 22.

The cylinder block 3 is rotatable within the inner space lO. Note that a joint hole 23 is formed at one end of the rotary shaft 2 to which a rotary shaft (not shown) of, for example, a speed reducer is connected. Furthermore, it goes without saying that the method of connecting the cylinder block 3 to the rotating shaft 2 may be arbitrarily selected, such as the above-mentioned spline connection.

The cylinder block 3 has a plurality of cylinder holes 30.
is drilled. A plunger 31 is inserted into the cylinder hole 30 from an opening at one end, and a shoe 32 is rotatably fitted to the tip of the plunger 31. The tip end surface of this shoe 32 corresponds to the sliding surface portion 42 of the swash plate 4.
is in contact with. The cylinder hole 30 has a boat 33 communicating with the boat hole 5a bored in the plate 5. This boat 33 is configured to selectively communicate with the supply oil passage 11 or the discharge oil passage 12 according to the rotation of the cylinder block 3. Further, this cylinder block 3 is provided with a suppressing device that always presses the cylinder block 3 against the plate 5 and the shoes 32 against the swash plate 4 at all times. That is, in rotation #12 near the center of the cylinder block 3, w! A space of an appropriate size is formed in the area where the I contact the cylinder block 3, and a stopper 34 is provided protruding from the cylinder block 3 in this space, and one piece 35a is engaged with this stopper 34, and a spring 36 is attached to this piece 35a. hold one end, and
The other end of the spring 36 is locked to the other piece 35b, and the rod 37 passing through the cylinder block 3 is brought into contact with the other piece 35b, and the cam 38 is brought into contact with the tip of this rod 37. A stopper piece 39 attached to the shoe 32 is brought into contact with the cam surface of the cam 38. That is, this suppression device
The cylinder block 3 is pressed against the play 1-5 by the repulsive force of 6, and the shoe 32 is pressed against the swash plate 4 by the stopper piece 39.

The swash plate 4 is formed to have a donut-like planar shape as a whole as shown in FIG. 3(A), and has a patterned side surface shape as a whole as shown in FIG. It is formed to have. The adjacent surface on the casing l side provided on the opposite side to the sliding surface portion 42 of the swash plate 4 is composed of a first seat surface 40 and a second seat surface 41 having different angles, and the first seat surface 40 and the second seat surface 7152 have different angles. The angle of the swash plate 4 is set to 2 by using one of the seat surfaces 41 as a stopper and bringing it into contact with the inner wall 1a which is the -p surface of the casing l.
It is possible to perform variable control to two speeds in accordance with the angle of the swash plate 4. That is, when the swash plate angle is changed, the plunger stroke changes, which changes the oil suction efficiency, and as the shaft speed changes, the output also changes. Shoe 32
The side sliding surface portion 42 is formed into an inclined surface with an angle larger than the inclination angle of the E2 second seat surface 41, and the OM plate 4 that allows the shoe 32 to slide is formed on the first seat surface 40. and the second seat surface 41 (hereinafter referred to as the intersection line O) as a fulcrum. Further, a ball hole 43 centered on the intersection line O between the seat surface 40 and the second seat surface 41 at t51 is formed, and a ball hole 43 is formed at a position corresponding to this ball hole 43. casing l
A ball 44 serving as a positioning member is held between a ball hole (V!J shown) formed in the inner wall with a slight gap therebetween, and the swash plate 4 is positioned by the ball 44. Therefore, when the auxiliary shoe 16 adjacent to the upper end of the first seat surface 40 moves to the left in FIG. 4 is tilted at a constant angle using the intersection line O as a fulcrum. Namely.

When no hydraulic pressure is acting on the auxiliary plunger 15 in the auxiliary syringe 14, the swash plate 4 always remains on its first seat surface 4.
0 as a stopper and is supported in contact with the inner wall 1a of the casing 1 (see FIG. 4(a)).

However, when pressurized oil is fed into the auxiliary cylinder 14 from the auxiliary oil passage 13 and the auxiliary plunger 15 moves to the left in FIG. 2, the swash plate 4 tilts about the intersection line O. At this time, the first seat surface 40 is separated from the inner wall of the casing 1, and instead, the second seat surface 41 of the swash plate 4 is supported by contacting the inner IJI 1 a of the casing l as a stopper (Fig. 4). (Refer to (b)), at this time, if the following equation is established between the pressing force f acting on the auxiliary shoe 16 and the pressing force F acting on the swash plate 4, the swash plate 4 will move on its second seat surface 41. This will maintain stable contact with the inner wall of the casing l. That is, fib/aXF and f<b
+X/a+iXF. When f=0, that is, the swash plate 4 stably contacts the inner wall of the casing l with its first seat surface 40, as shown in FIG. This is because the applied pressing force F acts on tb-21 which is eccentric by b' in the figure towards the upper end side from the center of the intersection line 0. Incidentally, the swash plate 4 is of course formed with an opening 45 through which the rotating shaft 2 can be inserted, and also has a groove portion to avoid contact with the bearing 21 when the swash plate 4 rotates. 46 and a notch 47 for avoiding contact between the stopper piece 39 attached to the shoe 32
Consideration has been taken to ensure that the formation of
(See b)).

As the positioning member, a hemispherical protrusion or a cylindrical or semi-cylindrical member is protruded at a position corresponding to the ball hole 43, and a corresponding receiving part is formed on the inner wall of the adjacent casing l for positioning. It may also be one that allows rotation of the member.

The hydraulic motor A according to the embodiment of the present invention configured as described above operates as follows.

When the auxiliary plunger 15 installed on the back of the swash plate 4 is in an unpressurized state, the cylinder block 3 is pressed against the plate 5, and the shoes 32 are pressed against the swash plate 4, so that the plate 5 and the cylinder block If oil is supplied into the cylinder hole 30, the cylinder block 3 will immediately open without causing oil leakage from adjacent locations such as between the cylinder hole 30 and the cylinder block 3, or causing the cylinder block 3 to become unable to rotate due to this. It will rotate.

Oil is sent into the cylinder hole 30 and the plunger 31 is #
l! ff movement, oil in the cylinder hole 30 is sequentially supplied and discharged. That is, when the cylinder block 3 is rotated in either direction, the plunger 31 compresses and enters the cylinder hole 30, and the boat 33 communicates with the crescent-shaped hole 5a formed in the plate 5, and the cylinder The oil in the hole 30 is drained. On the other hand, plunger 3
1 extends, the boat 5b behind the cylinder block 3
The boat 33 is brought into communication with the boat 33, and oil begins to enter the cylinder hole 30, and these operations are selectively repeated until the plunger 3 in the plurality of cylinder holes 30
Slide 1 ii! Since the cylinder block 3 is moved, the cylinder block 3 rotates, and the rotating shaft 2 connected thereto is rotationally driven. Therefore, the rotational drive of the one-rotation shaft 2 can be stopped by canceling the supply of oil. As described above, the shoe 32 is always pressed against the swash plate 4 even when oil is not supplied.

There is no difference in the operation from the above when the swash plate 4 is in either of the cases shown in FIG. 4 (A) and (B). However, in the case of FIG. When the seat surface 40 of the swash plate 4 is supported in surface contact with the inner wall of the casing l, in the case of FIG.
The only difference is that the rotation of the rotating shaft 2 is slower than when the seat surface 41 of the rotary shaft 2 is supported in surface contact with the inner wall of the casing l. The tilting operation of the swash plate 4 has been described above, and the auxiliary plunger 15 and the auxiliary shoe 16 are
The first seat surface 40 of the swash plate 4 is not always pressed against the casing 1 when oil is not supplied to the auxiliary cylinder 14. Since it is in surface contact with the inner wall of the auxiliary plunger 15, no thrust is required from the auxiliary plunger 15 at this stage. Also,
When the inside of the auxiliary cylinder 14 is supplied with oil from the auxiliary oil passage 13 and becomes pressurized, the second seat surface 41 of the swash plate 4 comes into surface contact with the inner wall of the casing l and becomes stable. Further, the thrust force of the auxiliary plunger 15 does not need to be large; it is sufficient that the thrust force required for the auxiliary plunger 15 falls within the range where the above-mentioned formula holds true.

The above configuration and operation are examples of a hydraulic morph of the present invention, but when an example of a hydraulic pump is used instead, it is sufficient to rotate the rotating shaft 2 described in (h) as the NA moving shaft. Needless to say, high-speed and low-speed discharge can be performed at will.

As described above, according to the present invention, it is possible to obtain a hydraulic motor that can be freely changed to two speeds, high speed or low speed. Moreover, since the stopper is brought into contact with one plane of the casing, either the first seat surface or the second seat surface, the following effects can be obtained.

■Durability is improved because the contact area of the stopper can be increased.

■Since the inclination angle is determined only by the machining accuracy of the 2Y plane of the swash plate, high accuracy can be obtained, no extra adjustment of the inclination angle is required, and the structure is simple.

■The flat surface of the casing can be easily made by turning.

■The slope angle does not change during the process and is stable.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a variable hydraulic motor according to the present invention, FIG. 2 is a vertical sectional view showing a hydraulic motor according to the present embodiment, and FIG.
Figure (A) is a front view of the swash plate, Figure 3 (B) is a side view of the swash plate, and Figures 4 (A) and 4 (B) are side views showing the operating state of the swash plate. ■... Casing, 2... Rotating shaft, 3... Cylinder block, 4... Swash plate, 5... Plate, 13...
... Auxiliary oil passage, 14... Auxiliary cylinder, 15... Auxiliary plunger, 16... Auxiliary shoe, 31... Plunger, 32... Shoe, 40... First seat surface, 41 ...Second sheet surface, 42...Sliding surface portion 24
4...Ball, 0...Cross line, P...Press member.

Claims (1)

[Claims] a casing, a rotating shaft pivotally connected to the casing,
It consists of a cylinder block connected to the rotating shaft, and a swash plate on which a shoe fitted to the end of a plunger inserted into the cylinder block comes into contact, and the swash plate has a sliding surface portion on which the shoe comes into contact, and a swash plate on which the shoe comes into contact. having a first seat surface and a second seat surface with different angles provided on the opposite side of the sliding surface part,
The swash plate is a hydraulic motor that tilts about a line of intersection between a first seat surface and a second seat surface as a fulcrum. A variable hydraulic motor characterized by a stopper that comes into contact with the motor.