JP3793946B2 - Rotary cylinder - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a rotary cylinder that combines a linear reciprocating motion and a rotational motion of a required angle.
[0002]
[Prior art]
An example of such a cylinder is described in Japanese Patent Application Laid-Open No. 6-33908 previously proposed by the present applicant. In this fluid pressure cylinder device, a piston rod is provided to be rotatable with respect to a cylinder cover, and a roller that rotates integrally with the piston rod is provided in the cylinder tube. On the inner surface of the cylinder cover, cam members that engage with each other as the rollers move in the axial direction and rotate the rollers are provided. One cam member is for rotating the roller with respect to the forward movement, and the other cam member is for rotating the roller with respect to the backward movement. The guide groove is provided, and the roller (piston rod) is rotated once by an integer number of movements every time the piston rod moves forward and backward.
[0003]
[Problems to be solved by the invention]
However, according to such a structure, a roller must be provided in the middle of the piston rod in the cylinder tube, and a cam member having several guide grooves must be provided on the roller and the cylinder cover. Since the cylinder has a complicated internal structure different from that of a normal fluid pressure cylinder, the manufacturing cost increases. Further, in order to cause rotation of the roller (piston rod) by engaging the cam members with each other in the installation space for the roller in the middle of the piston rod, the cam member on the roller side, and the cam member on the cylinder cover side. The stroke length must be secured in the cylinder tube, the cylinder length becomes longer, and the linear motion is converted into rotational motion by the engagement of cam members having several guide grooves. However, there is a problem that the cam member has to be sized to have sufficient strength, and the diameter of the cylinder tube becomes large.
[0004]
SUMMARY OF THE INVENTION An object of the present invention is to provide a rotary cylinder that can generate a rotational movement with a straight reciprocating motion by simply using a normal fluid pressure cylinder as it is and adding a simple part to the outside thereof. It is in.
[0005]
[Means for Solving the Problems]
The rotary cylinder of the present invention comprises a fluid pressure cylinder that expands and contracts a piston rod by sliding a piston in a cylinder tube with fluid pressure, and an outer cylinder arranged on the outer periphery thereof. The outer cylinder is driven by the piston rod. The cam is connected to the piston rod so that the outer cylinder is provided with a cam groove having a straight portion and a curved portion, and is slidably fitted to the cam groove on the outer peripheral surface of the rod side cover of the hydraulic cylinder. The outer cylinder is rotated by sliding between the cam and the curved portion of the cam groove, and the rod side port of the fluid pressure cylinder is opened from the cam .
[0006]
As a preferred specific configuration, a plug having a rod-side port is implanted in the rod-side cover, and a cam that is slidably fitted to the cam groove of the outer cylinder is provided on the outer periphery of the plug. The structure protrudes from the cam groove. The outer cylinder and the tip of the piston rod are connected by a rotary bearing provided at the tip of the outer cylinder. The outer cylinder is slidably fitted to the rod side cover of the fluid pressure cylinder. A work member for performing a desired work can be attached to the outer end of the outer cylinder.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described in detail with reference to the drawings.
[0008]
The structure will be described with reference to FIGS. 1 to 4. The rotary cylinder includes a fluid pressure cylinder 1 and an outer cylinder 2 disposed on the outer periphery thereof. The fluid pressure cylinder 1 of the present example has a structure similar to that of a normal cushion type air cylinder, and the rod 4 is slidably fitted into the cylinder tube 3 and slidably penetrates the piston rod 5. A cushion pad 7 is provided on the inner surface of the cover 6, and a recess 9 and a cushion pad 10 serving as a cushion chamber are provided on the inner surface of the head-side cover 8.
[0009]
The head side cover 8 is provided with a head side port 11, but the rod side cover 6 has a plug 13 having a rod side port 12 screwed therein. A part of the plug 13 protrudes from the outer peripheral surface of the rod side cover 6, and a cam 14 that is a circular ring is fitted to the outer periphery of the protruding portion. A part of the cam 14 is also fitted in a recess formed on the outer surface of the rod side cover 6 and is fixed to the outer peripheral surface of the rod side cover 6 integrally with the plug 13. If the cam 14 having the rod side port is provided on the rod side cover 6, the plug 13 can be omitted.
[0010]
The outer cylinder 2 has an inner diameter that is slidably fitted to the outer peripheral surface of the rod-side cover 6 and has a length that covers the cylinder tube 3 including the rod-side cover 6 so as to form a gap. The cover 8 is not covered. The distal end opening of the outer cylinder 2 is closed by an outer cylinder cover 15 screwed into the distal end portion. In the circular recess 16 at the center of the outer cylinder cover 15, the outer cylinder 2 is coupled to the tip of the piston rod 5 by screwing a bolt 18 into the screw hole at the tip of the piston rod 5 with the rotary bearing 17 interposed therebetween. 5 is configured to slide together.
[0011]
The outer cylinder 2 is provided with a cam groove 19 slidably fitted to the cam 14. The cam groove 19 continuously forms a straight portion 19a and a curved portion 19b, and one end on the straight portion 19a side is a blind end that ends in the middle of the outer cylinder 2, but the other side on the curved portion 19b side The end is an open end that opens at the other end of the outer cylinder 2. The protruding portion of the plug 13 always protrudes from the cam groove 19 to the outside of the outer cylinder 2.
[0012]
Next, the operation will be described with reference to FIGS.
In this rotary cylinder, for example, the head side cover 8 of the fluid pressure cylinder 1 is fixed, and a work member 20 for performing a desired work is attached to the outer side of the outer end of the outer cylinder. When the piston 4 is moved forward by the supply pressure from the head side port 11, the outer cylinder 2 also moves forward integrally with the piston rod 5. In the forward movement stroke, in the range L1 (see FIG. 2) in which the linear portion 19a of the cam groove 19 slides with respect to the cam 14, the outer cylinder 2 advances straight (straight line) as shown in FIGS. In the range L2 (see FIG. 2) in which the curved portion 19b of the cam groove 19 slides with respect to the cam 14, the outer cylinder 2 moves forward while rotating as shown in FIG.
[0013]
On the other hand, when the piston 4 is moved backward by the supply pressure from the rod side port 12, the outer cylinder 2 is also moved backward together with the piston rod 5. In the reverse stroke, in the range L2 in which the curved portion 19b of the cam groove 19 slides with respect to the cam 14, the outer cylinder 2 moves backward while rotating in the opposite direction, and the linear portion 19a of the cam groove 19 In the range L <b> 1 that slides with respect to the cam 14, the outer cylinder 2 moves straight back as it is.
[0014]
In this example, the rotation angle of the outer cylinder 2 is 90 degrees, but it goes without saying that the angle can be arbitrarily set by the curved portion 19 b of the cam groove 19. The fluid pressure cylinder 1 may be a hydraulic cylinder.
[0015]
If a gripper is used as the working member 20, the rotary cylinder can be used as a uniaxial robot. If a bar is used as the working member 20, it can be used as a rotary clamp. If an arm is used as the working member 20, it can be used as a hanger.
[0016]
【The invention's effect】
As described above, according to the rotary cylinder of the present invention, by using a normal fluid pressure cylinder as it is and adding an outer cylinder, which is a simple part, to the outside of the cylinder, a rotational motion is also generated with a straight reciprocating motion. since it is possible to, Ru can significantly reduce the manufacturing cost as compared with the prior art. In addition, since the cam that slidably fits with the cam groove of the outer cylinder is provided on the outer peripheral surface of the rod side cover of the fluid pressure cylinder, the entire cylinder including the rod side cover of the fluid pressure cylinder is covered with the outer cylinder. Since the outer cylinder can be retracted, the overall size can be reduced, and the overall length when the outer cylinder is retracted can be shortened. Moreover, since the rod side port of the fluid pressure cylinder is opened from the cam, piping and maintenance are easy even if an outer cylinder is added .
[Brief description of the drawings]
FIG. 1 is a side view in which an upper half portion from a center line of an embodiment of the present invention is taken as a cross section.
FIG. 2 is a plan view of the above.
FIG. 3 is an end view of the rod side.
FIG. 4 is an end view of the head side.
FIGS. 5A and 5B are operation diagrams of a usage example, where FIG. 5A is a plan view and FIG. 5B is an end view on the rod side;
6A and 6B are operation diagrams in which the outer cylinder advances straight from the state of FIG. 5, and FIG. 6A is a plan view, and FIG. 6B is an end view on the rod side.
7A and 7B are operation diagrams in which the outer cylinder is rotated from the state of FIG. 6, in which FIG. 7A is a plan view and FIG. 7B is an end view on the rod side.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Fluid pressure cylinder 2 Outer cylinder 3 Cylinder tube 4 Piston 5 Piston rod 6 Rod side cover 7 Cushion pad 8 Head side cover 9 Head side cover recessed part 10 Cushion pad 11 Head side port 12 Rod side port 13 Plug 14 Cam 15 Outer cylinder Cover 16 Concave part 17 of outer cylinder cover Rotating bearing 18 Bolt 19 Cam groove 19a Straight line part 19b Curved part 20 Working member

Claims (5)

The piston rod includes a fluid pressure cylinder that expands and contracts the piston rod by sliding the piston in the cylinder tube by fluid pressure, and an outer cylinder disposed on the outer periphery of the cylinder. The piston rod is driven by the piston rod. The outer cylinder is provided with a cam groove having a straight portion and a curved portion, and a cam that is slidably fitted to the cam groove is provided on the outer peripheral surface of the rod side cover of the fluid pressure cylinder. A rotary cylinder characterized in that an outer cylinder is rotated by sliding between the cam and a curved portion of a cam groove, and a rod side port of a fluid pressure cylinder is opened from the cam . A plug having a rod-side port is implanted in the rod-side cover, and a cam that is slidably fitted to the cam groove of the outer cylinder is provided on the outer periphery of the plug, and a part of the plug protrudes from the cam groove. The rotary cylinder according to claim 1.   The rotary cylinder according to claim 1 or 2, wherein the outer cylinder and the tip of the piston rod are connected by a rotary bearing provided at the tip of the outer cylinder.   The rotary cylinder according to claim 1, 2, or 3, wherein the outer cylinder is slidably fitted to the rod side cover of the fluid pressure cylinder.   The rotary cylinder according to claim 1, 2, 3, or 4, wherein a working member for causing a target work to be performed is attached to an outer end portion of the outer cylinder.

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