JP2557635Y2 - Stopper device for swash plate actuator of swash plate type hydraulic pump - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stopper device for a swash plate actuator for changing a swash plate angle of a swash plate type hydraulic pump.

[0002]

2. Description of the Related Art As shown in FIG.
A cylinder block 3 is rotatably provided together with a shaft 2 in a case 1, and a piston 5 is inserted into a cylinder hole 4 of the cylinder block 3 to form a cylinder chamber 6.
This cylinder chamber 6 is connected to a suction port 9 by a port 8 of a valve plate 7.
The piston shoe 11 provided on the piston 5 is slidably pressed along the swash plate 12, and the angle of the swash plate 12 is changed to increase or decrease the stroke of the piston 5. The angle of the swash plate 12 is controlled by the piston 13 of the swash plate actuator A.
Is connected to the swash plate 12, and the piston 1
3 slides left and right to swing the swash plate 12
The angle has changed. With this swash plate angle changing structure, the swash plate angle is determined by the stroke of the piston 13, so that the stroke of the piston 13 can be adjusted by the stopper device. For example, as shown in FIG. 1, a screw hole 16 is formed concentrically with the piston hole 15 in the case 1, a screw rod 17 is screwed into the screw hole 16 and fixed with a lock nut 18 to form a stopper device B, The lock nut 18 is loosened to tighten the screw rod 17, and the screw rod 17 is loosened to enter and exit to regulate the stroke end of the piston 13 to adjust the stroke.

[0003]

With such a stopper device, the impact force when the piston 13 collides with the screw rod 17 is supported by the engagement between the screw rod 17 and the screw hole 16, but the case 1 is made of a casting. Therefore, the mechanical strength is weak and the length L of the screw hole 16 becomes long.
When the lock nut 3 is hit with the screw rod 17 and an impact force is applied, the locking axial force of the lock nut 18 is reduced.
8 is easy to loosen.

Accordingly, an object of the present invention is to provide a stopper device for a swash plate actuator of a swash plate type hydraulic pump which can solve the above-mentioned problem.

[0005]

A projecting wall is integrally provided on a case, and a screw hole of the stopper wall is screwed into a screw hole of the projecting wall, and a lock nut screwed into the screw portion is a piston on the projecting wall. Fastened to the inner surface facing the hole.

[0006]

[Operation] The impact force is supported by the engagement portion of the screw portion of the stopper rod and the engagement portion of the lock nut. When the impact force is applied, the lock nut is pressed against the inner surface of the protruding wall, and the lock nut is loosened. Absent. Further, since the stopper rod and the lock nut can be made of a material having higher mechanical strength than a casting, the engagement length L can be reduced.

[0007]

[Embodiment] An embodiment of the present invention will be described with reference to FIG. The same members as those in the related art have the same reference numerals. As shown in FIG. 2, a substantially U-shaped concave portion 19 is formed continuously with the opening of the piston hole 15 in the case 1, and a projecting wall 20 facing the piston hole 15 is integrally provided. 20, a screw hole 21 is formed concentrically with the piston hole 15,
The screw part 23 of the stopper rod 22 is screwed into the screw hole 21, and the piston part 24 of the stopper rod 22 is fitted into the piston hole 15 and sealed with a sealing material 25. 26 is screwed and fastened to the inner surface 20a of the protruding wall 20 facing the piston hole 15 to form a stopper device B.

[0008]

According to the present invention, the piston 13 is moved by the stopper rod 2 at the engagement portion between the screw portion 23 of the stopper rod 22 and the lock nut 26.
2, the length L of the screw hole 21 provided integrally with the case 1 can be shortened, and the lock nut 26 is attached to the inner surface 2 of the protruding wall 20 when the impact force is applied.
Since it is pressed to 0a, the lock nut 26 does not loosen without the tightening axial force being reduced.

[Brief description of the drawings]

FIG. 1 is a sectional view of a conventional swash plate type hydraulic pump.

FIG. 2 is a sectional view of the swash plate type hydraulic pump according to the present invention.

[Explanation of symbols]

1 case, 12 swash plate, 13 piston, 14 pin, 15 piston hole, 20 protruding wall, 20a inner surface, 21 screw hole, 22 stopper rod, 23 screw portion,
24 piston part, 26 lock nut.

Claims (1)

(57) [Scope of request for utility model registration] The piston 1 is inserted into a piston hole 15 of the case 1.
3 and the pin 14 provided on the piston 13 is connected to the swash plate 12, and the swash plate 12 is slid by sliding the piston 13.
A swash plate actuator of a swash plate type hydraulic pump for changing the angle of
1 is screwed with the screw portion 23 of the stopper rod 22, and the piston portion 24 of the stopper rod 22 is fitted into the piston hole 15,
A lock nut 26 is screwed into the screw portion 23 to project the protruding wall 2.
A stopper device for a swash plate actuator of a swash plate type hydraulic pump, wherein the stopper device is fastened to an inner side surface 20a.