JPH0337041B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a composite actuator that integrates an oscillating actuator and a cylinder actuator to cause a piston rod to perform two movements: rotational oscillation and linear reciprocating motion. More specifically, the present invention relates to a piston sealing mechanism in the above composite actuator.

[Prior Art] Working machines driven by actuators include not only rotary oscillation or linear reciprocating motion, but also linear reciprocating and rotational oscillating motion, or linear drive. Some require complex movements such as rotating and swinging at the end.

In order to drive work machines that require such compound movements, it is conceivable to connect a swing-type actuator and a cylinder-type actuator to form a compound actuator, but the output shaft of this compound actuator is the piston rod. Since the piston performs two compound movements, linear reciprocating motion and rotational oscillation, there is a problem in that the seal packing provided on the piston wears out in a short period of time, and there was a need to solve this problem.

[Problems to be Solved by the Invention] The present invention provides a compound actuator in which the piston rod performs a combined movement of linear reciprocating motion and rotational oscillation, and a seal packing provided on the piston is configured to perform a combination of linear reciprocating motion and rotational oscillation. The problem to be solved is to prevent wear by subjecting the compound actuator to motion in only one direction, thereby increasing the life of the compound actuator.

[Means for Solving the Problems] The present invention provides a structure in which the shaft of a swing-type actuator and the piston rod of a cylinder-type actuator are arranged such that the piston rod is integrally rotatable with respect to the shaft and the piston rod is rotated in the axial direction of the piston rod. In the compound actuator connected so as to be relatively slidable, the piston of the cylinder type actuator is rotatable relative to the piston rod and reciprocated integrally with the piston rod in the axial direction of the piston rod. The above problems are solved by providing a rotating seal packing between the piston and the piston rod and a sliding seal packing between the piston and the cylinder.

[Operation] When pressure fluid is supplied to and discharged from the swing type actuator and the cylinder type actuator, the piston rod performs a compound movement of linear reciprocating motion in the axial direction and rotational oscillation, and in this compound movement, the piston moves relative to the piston rod. Since the piston is relatively rotatable and reciprocated integrally with the cylinder, the piston reciprocates linearly without rotating with respect to the cylinder, and only the piston rod rotates.

Therefore, only the sliding force due to linear reciprocating motion acts on the seal packing between the piston and cylinder.
Only the sliding force due to rotational motion acts on the seal packing between the piston and the piston rod, and neither seal packing receives sliding force due to the combined movement of linear reciprocating motion and rotation.

[Example] Fig. 1 shows an example of the present invention, and shows a vane type actuator 1 which is an example of a swing type actuator.
The body 4 of the cylinder type actuator 2 and the cylinder 20 of the cylinder type actuator 2 are integrally connected by a mounting bolt or the like (not shown) screwed onto the cylinder 20 through mounting holes 5 provided in the body 4. A recess 6 formed in the body 4 and a recess 2 formed in the end surface of the cylinder 20 on the body 4 side.
1 forms a pressure chamber 7 of the vane type actuator 1 by coupling the body 4 and the cylinder 20.

Vane 10 of the vane type actuator 1 above
has a vane 12 integrally attached to the vane shaft cylindrical part 11 and shafts 13a and 13b formed at both ends of the vane shaft cylindrical part, and the vane 12 swings in contact with the inner surface of the pressure chamber 7. Possibly inserted. Further, one shaft 13a projects outside the body 4 through a through hole 8 formed in the body 4, and the other shaft 13b passes through a shaft hole 22 formed in a recess 21 of the cylinder 20 into a cylinder shape. It protrudes into the piston chamber 23 of the actuator 20.

The shafts 13a and 13b have a through hole 8 and a shaft hole 2.
It is rotatably supported by bearings 14, 14 fitted to the
On the circumferential surface of the shaft 13b, there are two engagement planes 15 that are longer in the axial direction than the stroke of the piston 24, which will be described later.
15 are formed facing away from each other.

As shown in FIG.
Accordingly, the blade 12 is divided into two pressure chambers on both sides, and ports 17 and 18 for supplying and discharging pressurized air are opened in these pressure chambers, respectively.

On the other hand, a piston rod 25 to which a piston 24 is rotatably attached is inserted into the piston chamber 23 of the cylinder-type actuator 20, and the piston rod 25 has a tip opening of a shaft insertion hole 27 formed in the end surface of the shaft 13b. A shaft connector 29 having a shaft connection hole 28 into which the shaft 13b is loosely fitted is fixed to the shaft connector 29 by appropriate means. The shaft insertion hole 27
has a depth greater than the stroke of the piston 24. Also, piston rod 25
The other end is connected to the cylinder 20 by a retaining ring 30.
It is made to protrude outside the cylinder 20 through a rod hole 32 of an end plate 31 fixed to the cylinder 20.

As shown in FIG. 3, the shaft connection hole 28 of the shaft connection tool 29 has planar portions facing each other, and the shaft 13b
The shaft 13b and the piston rod 25 are loosely fitted with the engaging flat surfaces 15, 15 opposed to the flat portion, and the shaft 13b protrudes into the shaft insertion hole 27.
are integrally rotatable, and are connected so that the piston rod 25 is slidable in the axial direction with respect to the shaft 13b.

Piston 2 attached to piston rod 25
4, a bearing 34 is provided between the piston rod 25 and the enlarged diameter portion formed at the end on the shaft 13b side, and a bearing 35 is provided between the other end surface of the piston 24 and a holding piece 36 attached to the piston rod 25. These bearings 34, 3
5, it is rotatable relative to the piston rod 25 and supported so as to linearly reciprocate integrally therewith.

A rotating seal packing 40 on the rod side and a sliding seal packing 41 on the cylinder side are fitted into the annular grooves 39a and 39b formed on the inner and outer circumferential surfaces of the piston 24, respectively. A seal packing 40 is provided between the piston 24 and the piston rod 25, and a sliding seal packing 41 is provided between the inner surface of the cylinder 20 and the piston 24.
A seal is placed between each.

Further, ports 42 and 43 are formed in the cylinder 20 to alternately supply and discharge pressure fluid to both sides of the piston 24 in the piston chamber 23.

In the above composite actuator, ports 17 and 18 are provided in the pressure chamber between the blade 12 and the stopper 16.
When pressure fluid is supplied and discharged from the ports 42 and 43 to the piston chamber 23, the shafts 13a and 13b of the vane 10 swing, and the piston rod 25 reciprocates in its axial direction. Since the piston rod 25 is attached to the shaft 13b of No. 10 so as to be integrally rotatable and slidable relative to each other in the direction of their axes, the piston rod 25 can perform a compound motion of rotational oscillation and linear reciprocating motion. do.

On the other hand, since the piston 24 is mounted so as to be rotatable relative to the piston rod 25 and to reciprocate integrally with the piston rod 25, the piston 24 can also rotate within the piston chamber 23. However, when the piston rod 25 is rotated by the shaft 13b of the vane 10, the contact area between the piston 24 and the inner wall of the piston chamber 23 is larger than the contact area between the piston 24 and the piston rod 25. The resistance to rotation between the piston chamber 23 and the inner wall increases, the piston 24 does not rotate relative to the cylinder 20, and eventually the concave grooves 39a of the piston 24,
Seal packing 4 on the rod side fitted to 39b
0 receives only the sliding movement in the rotational direction between the piston 24 and the piston rod 25, while the seal packing 41 on the cylinder side receives only the sliding movement in the axial direction between the piston 24 and the piston chamber 23.

Therefore, the seal packings 40 and 41 are subjected to only rotational or linear reciprocating motion, and are not subjected to combined rotational and linear reciprocating motion, so seal packings having configurations corresponding to these movements are required. Kings can be used and their wear can be suppressed.

In the above embodiment, the vane-type actuator 1 is used as the swing-type actuator, but the present invention is not limited to this, and other well-known swing-type actuators such as a rack-pinion type and a crank-type may be used. Can be done.

[Effects of the Invention] The present invention provides a structure in which the shaft of a swing-type actuator and the piston rod of a cylinder-type actuator can be rotated integrally with respect to the shaft,
In addition, by connecting the piston rod so that it can slide relatively freely in the axial direction, the piston rod can perform a combined movement of linear reciprocating motion and rotation. Since the piston rod is integrally and slidably connected in the axial direction, the seal packings provided between the piston and the cylinder and between the piston and the piston rod are only subjected to linear reciprocating motion or rotational motion. As a result, the actuator is not subjected to a combined movement of linear reciprocating motion and rotation, thereby reducing wear on the seal packing and increasing the life of the combined actuator.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional front view showing an embodiment of the present invention, FIG. 2 is a partially cutaway plan view of the vane type actuator with the cylinder type actuator removed,
FIG. 3 is a sectional view taken along line A--A in FIG. 1. 1... Vane type actuator, 2... Cylinder type actuator, 13a, 13b... Shaft, 2
4... Piston, 25... Piston rod, 4
0,41... Seal patch king.

Claims (1)

[Claims] 1. A composite actuator in which the shaft of a swing-type actuator and the piston rod of a cylinder-type actuator are connected such that the piston rod is rotatable integrally with respect to the shaft and is slidable relative to the axial direction of the piston rod. The piston of the cylinder type actuator is mounted so as to be rotatable relative to the piston rod and to reciprocate integrally with the piston rod in the axial direction of the piston rod, and a rotary sealing pad is provided between the piston and the piston rod. 1. A piston seal mechanism for a composite actuator, characterized in that a sliding seal packing is provided between the piston and the cylinder, and a sliding seal packing is provided between the piston and the cylinder.