JPH0456889B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Field of Industrial Application The present invention relates to a rodless cylinder that does not have a piston rod, and more specifically, to a rodless cylinder that does not have a piston rod, and more specifically to a rodless cylinder that does not have a piston rod. This invention relates to a rodless cylinder with a brake mechanism that can be stopped at any position.

(b) Prior Art Conventionally, rodless cylinders have been provided with a brake mechanism to stop the piston midway through its stroke. As a conventional rodless cylinder with a brake mechanism, there is one shown in European Patent Publication No. 0136435, for example. In this rodless cylinder, as shown in FIGS. 10 and 11, a brake mechanism c is attached to a table b that moves together with the piston of the rodless cylinder a, and the brake mechanism c is operated by fluid pressure as a power source. The brake mechanism is operated by using a brake cylinder d and supplying and discharging fluid pressure to and from a cylinder chamber e of the brake cylinder d through a port f. In such a structure, the piping to the port f of the brake cylinder d is connected to the external fluid pressure supply source of the rodless cylinder a, and the supply and discharge of fluid pressure to the brake cylinder d is connected to the table b. Must be done with a control valve.

However, with such conventional rodless cylinders, the fluid pressure piping is pulled as the table moves, making it difficult to handle the piping and wasting space, especially when the stroke is long. There is.

(c) Problems to be solved by the present invention The problem to be solved by the present invention is to eliminate the inconvenience caused by the piping for the brake mechanism in a rodless cylinder by eliminating the dragging of the piping, and also to eliminate wasted space. It is.

(d) Means for Solving the Problems The present invention provides a cylinder tube having a slit extending in the axial direction on its outer periphery, an end cover that closes both ends of the cylinder tube, and a movably disposed inside the cylinder tube. In the rodless cylinder, the table is connected to the piston via a connecting member extending in and out of the cylinder tube through the slit, and the table part has a brake operated by the force of the brake cylinder. at least one of the pistons is provided with a passage communicating with a cylinder chamber adjacent to the piston, the passage is connected to the brake cylinder via a control valve that moves together with the table, and the passage is connected to the brake cylinder adjacent to the cylinder tube. A cam extending along the cylinder tube is provided, and a cam follower is provided on at least one of the table and the connecting member to engage with the cam and control the operation of the control valve according to the shape of the cam. .

(E) Operation In the above configuration, when fluid pressure is alternately supplied to the chambers on both sides of the piston in the cylinder tube, the piston reciprocates. When stopping the piston, the supply of fluid pressure is stopped, and the control valve is switched to stop the supply of fluid pressure to the brake cylinder, and the fluid pressure in the brake cylinder is discharged to operate the brake, and the piston is stopped. apply the brakes.

(f) Examples Examples of the present invention will be described below with reference to the drawings.

1 to 5, a rodless cylinder 1 with a brake mechanism according to a first embodiment is shown. In the figure, reference numeral 2 denotes a cylinder tube that defines a cylinder hole 21 whose cross section is oval as shown in FIG. 3
a, 3b) are end covers fitted to both ends of the cylinder tube 2, and 4 (4a, 4b) have the same planar shape as the cross-sectional shape of the cylinder hole 21 and move within the cylinder hole 21 at a distance from each other. A pair of pistons that can be provided, 5 is a pair of pistons 4
are connected to each other and a portion 51 projects outward through the slit 22 of the cylinder tube 2, and 6 is a table connected to the connection member on the outside of the cylinder tube 2. In this embodiment, the connecting member and the table are made integrally. The portion 52 of the connecting member 5 that is inserted into the cylinder hole is bifurcated as shown in FIG. There is.

Inside the cylinder hole 21 of the cylinder tube 2,
A sealing member 7 that closes the slit 22 is provided. This seal member 7 has a cross section as shown in FIG. 3, and has a convex portion 71 extending in the axial direction that enters the slit 22 on the upper surface (in FIG. 3), and a convex portion 71 that extends in the cylinder hole on both sides of the slit 22. A pair of convex portions 72 are formed to fit into the concave portion 23 formed along. As shown in FIG. 2, the sealing member 7 has an intermediate portion that enters a bifurcated portion 52 along the lower surface of the portion 51 of the connecting member 5, and a portion near both ends that is connected to the inner surface of the cylinder tube 2 (convex portions 71 and 7) by the piston 4.
2 into the slit 21 and the recess 23 respectively), thereby creating a cylinder chamber defined by the piston 4 and the end cover 3.
The connecting member is allowed to protrude to the outside through the slit while preventing C ₁ and C ₂ from communicating with the outside of the cylinder tube through the slit. Fluid pressure is introduced into the cylinder chambers C ₁ and C ₂ through supply and discharge ports 31a and 31b of the end covers 3a and 3b.

A brake mechanism 8 is provided on the table 6. This brake mechanism 8 consists of a pair of levers 81 rotatably attached to a convex portion 61 on the lower surface of the table by a piston 62, and a pair of levers 81 attached to one end (the left end in FIG. 1) of the lever 81 on the side of the cylinder tube 2. a brake cylinder 83 mounted on the table 6 and connected to the other end of the lever 81; a control valve 84 mounted on the table 6 and connected to the brake cylinder 83; and a valve operating device. 85.

The brake cylinder 83 has a brake cylinder hole 831 formed in the table corresponding to the lever 81.
It has a piston 832 that is movably provided in the brake cylinder hole 831 and connected to the other end of the lever 81, and a spring 833 that presses the piston 832 upward.

A shuttle valve 9 of a known structure is provided between the bifurcated portion 52 of the connecting member 5 between the pair of pistons 4.
is installed. An inlet port 91 on one side (the right side in FIG. 2) of the shuttle valve 9 communicates with one cylinder chamber C1 via a through hole 41 formed in the piston _4a and a conduit 93, and an inlet port 92 on the other side communicates with the piston 4b. It communicates with the other cylinder chamber C ₂ via a through hole 41 . Outlet port 94 of shuttle valve 9 is connected to control valve 84 via conduits 95 and 96.

The control valve 84 may be a Norman open type electromagnetic valve with a known structure that can be controlled to open and close. Valve actuation device 85
has a wireless transmitter 851 and a receiver 852 that controls opening and closing of the control valve 84 in response to a valve operation signal from the transmitter. Note that the transmitter and receiver may have a known structure.

In the rodless cylinder configured as described above, the cylinder chamber C ₁ is
When fluid pressure is alternately supplied to C 2 and C ₂ , the pistons 4 (4a, 4b) reciprocate. At this time, the fluid pressure in the cylinder chamber C ₁ or C ₂ flows through the through hole 41 to the shuttle valve 9, and from there through the conduits 95, 96 and the control valve 84 to the brake cylinder hole 831.
The brake piston 832 flows into the spring 833.
Press against. Then the lever 81 is connected to the pin 62
The piston 4 can move freely because the brake shoe 82 is separated from the outer peripheral surface of the cylinder tube by rotating around the cylinder tube.

When stopping the piston in the middle of its full stroke, stop the supply of fluid pressure into the cylinder chamber C ₁ or C ₂ and send a brake start signal from the transmitter 851, and the receiver 852 performs control based on that signal. When switching the valve, brake cylinder hole 8
The brake piston 832 is pushed up by the action of the spring 833 because the supply of fluid pressure into the brake piston 31 is stopped and the fluid pressure therein is discharged. Therefore, one end of the lever (the right end in FIG. 1) is lifted and the brake shoe 82 comes into contact with the outer surface of the cylinder tube 2, applying a brake to the piston 4 and stopping the piston immediately.

6 to 9, another embodiment of the rodless cylinder 1a is shown. In the rodless cylinder of this embodiment, the control valve 84a is a manually operated norm open type switching valve, and the valve operating device 85A is a cam 851a attached to the side of the cylinder tube 2, and the control valve 84a
This embodiment differs from the previous embodiment in that it is composed of an arm 852a rotatably attached to the arm 852a and a cam follower consisting of a roller 853a rotatably attached to the tip of the arm 852a and engaging with the cam 851a. In that respect, they are almost the same. Therefore, the same parts will be given the same reference numerals as in the previous embodiment, and detailed explanation will be omitted.

In this embodiment, a ridge 855a is formed on the cam 851a at a position where the piston is desired to be stopped. Therefore, the roller 853 of the cam follower
When a reaches the position of the peak 855a, the control valve 84a
The valve stem 841a is pushed up by the arm 852a, switches the control valve 84a, thereby stopping the supply of fluid pressure into the brake cylinder hole 831, discharging the fluid pressure therein, and rotating the lever 81. It is designed to apply a brake to the piston.

In both of the above embodiments, a shuttle valve is provided so that the brake can be applied during both the reciprocating strokes of the piston, but if the brake only needs to be applied during the stroke in one direction, the cylinder chamber _C1 or
C ₂ may be connected directly to the control valve without going through the shuttle valve.

(g) Effects In the rodless cylinder with brake mechanism according to the present invention, fluid pressure piping is connected between the piston that moves together and the control valve attached to the table, so that the piping for the brake mechanism does not drag. There is no problem even with cylinders with large strokes. Additionally, the entire device can be made compact.

Furthermore, since the brake operation is controlled by a cam that extends along the cylinder tube, the structure is simple and the stopping position of the piston can be easily determined (simply by shifting the cam position or replacing the cam).
Can be changed.

[Brief explanation of drawings]

FIG. 1 is a side view of a first embodiment of a rodless cylinder with a brake mechanism according to the present invention, FIG. 2 is a longitudinal cross-sectional view of the cylinder shown in FIG. 1, and FIG. 4 is a sectional view taken along the line - in FIG. 2, FIG. 5 shows the relationship between the piston and the connecting member, and FIG. 6 is a rodless cylinder with a brake mechanism according to another embodiment. 7 is a longitudinal sectional view of the cylinder in FIG. 6, FIG. 8 is a sectional view taken along the line - in FIG. 7,
Figure 9 is a sectional view taken along the line - in Figure 7.
1 and 11 are diagrams showing a conventional rodless cylinder. It is. 1, 1a: Rodless cylinder, 2: Cylinder tube, 21: Cylinder hole, 22: Slit,
3: End cover, 4: Piston, 5: Connecting member, 6: Table, 8: Brake mechanism, 81: Lever, 82: Brake shoe, 83: Brake cylinder, 84, 84a: Control valve, 85, 85a:
Valve actuator.

Claims (1)

[Claims] 1. A cylinder tube in which a slit extending in the axial direction is formed on the outer periphery, an end cover that closes both ends of the cylinder tube, a piston movably disposed within the cylinder tube, and a piston that is movably disposed inside the cylinder tube, through the slit into and out of the cylinder tube. A rodless cylinder comprising a table connected to the piston via an extending connecting member, the table portion being provided with a brake operated by the force of a brake cylinder, and at least one of the pistons having a brake adjacent to the piston. a cam extending along the cylinder tube adjacent to the cylinder tube, the passageway being connected to the brake cylinder via a control valve that communicates with a cylinder chamber that moves with the table; A rodless cylinder with a brake mechanism, characterized in that at least one of the connecting members is provided with a cam follower that engages with the cam and controls the operation of the control valve according to the shape of the cam.