JPS63120904A - Cylinder device - Google Patents

Abstract

PURPOSE:To make a cylinder device compact and improve the travel accuracy of a driven body by internally mounting a stroke adjusting device for a cylinder rod in a cylinder casing. CONSTITUTION:A stopper piston 23 with a communicating hole 22 is internally mounted inside a cylinder rod 19, and is threadedly engaged with the tip of a screw rod 25 supported by a head cover 17, and forms a stroke adjusting device together with the screw rod 25. Since the provision of a separate positioning device becomes thereby unnecessary, a cylinder device becomes wholly compact. In addition to that, the stop position of the rod 19 can be directly adjusted, and the travel accuracy of a driven body is therefore certainly improved.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Field of Application> The disclosed technology applies to the field of structural technology for cylinder devices used as actuators for moving mechanical devices in various manufacturing plants.

Accordingly, the present invention provides a cylinder casing in which a piston is fitted into a cylinder casing having an inlet/outlet port for oil, air, etc. so as to be able to move back and forth freely, and is integrated with the piston by letting air, oil, etc. in and out from the inlet/outlet port. This invention relates to a cylinder device that moves a cylinder rod forward and backward, and in particular, this invention relates to a cylinder device in which a stroke adjustment device that can freely adjust the stroke of the cylinder rod is installed in the cylinder casing.

<Prior Art> As is well known, in machine manufacturing plants such as automobile manufacturing plants, many cylinder devices such as air cylinders and hydraulic cylinders are used as actuators to move various mechanical devices as desired.

Generally, in a factory, when mechanical equipment is to be moved accurately to a predetermined position, a transport vehicle equipped with the predetermined mechanical equipment is moved to the approximate position by a cylinder device, and then another An embodiment was adopted in which the body was positioned accurately by a body positioning device.

That is, as shown in FIG. 3, in this embodiment, a pump 4 is connected via a switching valve 3 to a double-acting hydraulic cylinder 2 as a cylinder device fixed on a floor 1, and the pump 4 is operated and switched. By switching the valve 3, the cylinder rod 5 of the hydraulic cylinder 2 is moved back and forth as appropriate to move the truck 6 attached to its tip to the approximate position, and the first truck 6 is set in a free state and attached to the truck 6. The tapered notch 8 of the positioning air cylinder 7 is lowered and fitted into the positioning groove 9 or 9' on the floor 1, thereby positioning the trolley 6 at the correct position P or P'. I was trying to position it.

A more specific positioning machine for the cart 6 to the P or P' position is a limit switch 10 when the cart 6, which has moved forward via the hydraulic cylinder 2, reaches the P (P') position.
(10') and the limit switch 10 (10')
), and the trolley 6 decelerated thereby further operates the limit switch 12 (12
') and puts the switching valve 3 connected to the limit switch 12 (12') into a neutral state, and at the same time operates the other switching valve 13 so that the hydraulic cylinder 2 can freely move under no load. The positioning air cylinder 7 is then moved to a predetermined position by operating the switching valve 14.

<Problems to be solved by the invention> However, the conventional cylinder device (hydraulic cylinder 2) has a structure in which the cylinder rod is simply moved forward and backward by taking in and out fluid such as oil in the cylinder casing. Therefore, when used in areas that require accurate positioning as described above, separate positioning devices (positioning air cylinder 7, notch 8, positioning groove 9, 9', etc.) must be provided. First, there was a problem in that the overall size of the adopted device was reduced and the cost became an issue.

In addition, the positioning device provided separately from the cylinder device generally performs accurate positioning by fitting the tapered notch with the positioning groove on the floor, as in the conventional method described above. After performing this, it is not possible to make new fine adjustments, and furthermore, the pushing force of the notch, the contact resistance between the notch and the positioning groove, the movement resistance of the cart, etc. are subtly related to accurate positioning. Another drawback was that it was difficult to ensure accuracy.

The purpose of this invention is to solve the problems of the cylinder device based on the above-mentioned prior art, and to make it possible to accurately control the stop position of the cylinder rod and prevent the device from being idle by providing a separate positioning device. It is an object of the present invention to provide an excellent cylinder device that enables highly accurate movement of a driven object without increasing its size, thereby benefiting the field of application of drive device technology in the mechanical industry.

<Means/effects for solving the problem> In accordance with the above-mentioned object, the structure of the present invention, which is the subject matter of the above-mentioned claims, is to solve the above-mentioned problem by using a piston integrated with the cylinder rod in the cylinder gauging. The cylinder is fitted internally so that it can be opened and retracted freely, and a fluid inlet/output port is provided.Furthermore, a stroke adjustment device for the cylinder rod is installed in the cylinder casing, so that fluids such as oil and air can be press-fitted from the specified fluid inlet/outlet ports of the cylinder casing. A technical measure is taken in which the exact forward end position of the cylinder rod when it moves forward together with the piston is determined by the adjustment of the stroke adjusting device.

<Example> Next, an example of the present invention will be described below based on FIG. Incidentally, the same reference numerals are used to describe the same parts as those of the conventional embodiment shown in FIG.

2' is a cylinder device which constitutes the gist of the present invention, and a head cover 17, 17' having fluid inlet/output ports 16, 16' is fitted and fixed at both front and rear ends of an outer cylinder 15 to form a cylinder casing 18; A piston 20 integrated with a cylinder rod 19 is slidably fitted inside the cylinder rod 19, and the tip of the cylinder rod 19 protrudes from the tip of the casing 18 in a sealed manner. Driven objects such as the above are screwed onto the drive body.

The cylinder rod 19 is formed with a cylindrical hollow part 21 whose center is coaxial with the outer peripheral surface of the cylinder rod 19, and a stopper piston 23 having a communication hole 22 is installed inside the hollow part 21 so as to be able to slide forward and backward. A threaded hole 24 is formed in the stopper piston 23 eccentrically by a predetermined distance tied from the axial center of the cylinder rod 19, into which the tip of a threaded rod 25 supported by the rear head cover 17 is screwed.

The base of the threaded rod 25 is hermetically and rotatably supported by the head cover 17 via a sealing material 26 and a radial bearing 27, and a handle attachment portion 28 is formed at the base end. On the other hand, a locking member 29 is fixed to the tip of the threaded rod 25 via a bolt 30 so as to be able to come into contact with an end surface 32 of the stopper piston 23.

In addition, the base of the cylinder rod 19 is connected to the rear helad cover 1.
It is screwed and fixed to the piston 20 together with an auxiliary member 35 having a recess 23 and a removable cushion projection 34, and a constricted part 36 is formed on the inner surface of the proximal end of the cylinder rod 19. A communication hole 37 having a smaller diameter than the constricted portion 36 is formed, through which the threaded rod 25 is inserted, and the cylinder rod 19 and the auxiliary member 35 are fixed in contact with each other, so that the stepped surface 38 becomes a seating surface for the stopper piston 23. It is designed to be.

Furthermore, the outer circumferential surface of the rear side of the stopper piston 23 is formed into a reduced diameter portion 39 that can be freely fitted into and removed from the reduced diameter portion 36 of the cylinder rod 19. communicated through.

Note that each fluid input/output port 16 of the cylinder casing 18.
16' is connected to the pump 4 and the oil tank 41 via the switching valve 3, and the tip of the threaded rod 25 and the threaded hole 24 of the stopper piston 23 are loosely screwed together.
The rotation of the stopper piston 23 allows the stopper piston 23 to easily move back and forth.

In the above configuration, when moving a driven object such as a transport vehicle (not shown) attached to the tip of the cylinder rod 19 to a predetermined target position using the cylinder device 2', the pump is first moved from the state shown in FIG. 4 and switch valve 3.
is operated in the right direction in the figure to supply oil from the pump 4 to the rear fluid input/output port 16, and at the same time communicate the front fluid input/output ports 1 to 16' with the oil tank 41, and the piston 20 and the cylinder rod are activated by the hydraulic pressure. 19 forward (to the right in the figure).

Then, when the piston 20 and the cylinder rod 19 are pushed forward, the stopper piston 23 screwed into the tip of the threaded rod 25 retreats relative to the cylinder rod 19, and at this time The oil in the hollow part 21 flows through the communication hole 22 of the stopper piston 23 and flows into the front of the hollow part 21.

In this way, when the cylinder rod 19 moves forward to a predetermined maximum, the stopper piston 23, which is held in position by screwing with the threaded rod 25, has its reduced diameter portion 39 fitted into the constricted portion 36 on the inner surface of the proximal end of the cylinder rod 19. When the end surface of the stopper piston 23 comes into contact with the stepped surface 38 of the auxiliary member 35, the forward movement of the cylinder rod 19 is stopped.

It should be noted that when the reduced diameter portion 39 of the stopper piston 23 is fitted into the constricted portion 36 of the cylinder rod 19, some particles remain in the area sandwiched between the outer circumferential surface of the reduced diameter portion 39 and the inner surface of the cylinder rod 19. Oil flows through the throttle hole 40 of the stopper piston 23
Since the cylinder rod 19 gradually flows into the communication hole 22, the resistance during the flow acts as a damper that absorbs the shock when the cylinder rod 19 stops.

In addition, after the driven object has been moved to the target position in this way, when returning it to the original position, the switching valve 3 is moved to the left in the figure, and the fluid input/output port 16 from the pump 4 is moved to the front.
' At the same time, the oil is supplied to the cylinder casing 18.
The oil inside flows into the oil tank 41 from the rear fluid inlet/output port 16, and the oil pressure generated by the pump 4 drives the piston 2.
0, and push the cylinder rod 19 back.

At this time, the stopper piston 23 moves forward relative to the cylinder rod 19, contrary to when the cylinder rod 19 moves forward, and the oil in front of the hollow part 21 of the cylinder rod 19 flows into the communication hole 22 of the stopper piston 23. and flows out to the rear of the hollow part 21.

In this way, when the cylinder rod 19 retreats by a predetermined amount, the cushion protrusion 34 of the auxiliary member screwed onto the piston 20 comes to fit into the recess 33 of the rear head cover 11, and the cylinder rod 19 and piston 20 The retraction speed is gradually reduced by the mating resistance at that time,
The retracting operation is stopped when the cushion protrusion 34 and the recess 33 are completely fitted.

When finely adjusting the moving position of the driven object, first, the switching valve 3 is held in the neutral position as shown in FIG. direction.

When the threaded rod 25 rotates in a predetermined direction, the stopper piston 23 does not rotate synchronously with the threaded rod 25 because the axial center of the stopper piston 23 and the threaded hole 24 are set eccentrically. It becomes active within the section 21 and moves in a predetermined direction.

In this way, the stopper piston 23
5 is adjusted, and as a result, the timing at which the reduced diameter portion 39 of the stopper piston 23 and the constricted portion 3G of the cylinder rod 19 fit together becomes faster or slower, and therefore the predetermined rotation of the threaded rod 25 is adjusted. The forward and backward stroke of the cylinder rod 19 can be freely adjusted by
Correspondingly, the moving position of the driven object is also adjusted.

Further, in the above embodiment, the threaded rod 25 is manually rotated, but as shown in FIG. 2 as another embodiment,
A gear 42 is attached to the base end of the threaded rod 25, and the motor 4
Further, the motor 43 and the row encoder 46 are electrically connected to an external controller 47 to automatically determine the moving position of the driven object. I also look at what I did.

In this case, positioning can be performed with a small motor that only moves the stopper piston, making it possible to realize a compact and powerful positioning device.

It should be noted that the embodiments of the present invention are of course not limited to the above-mentioned embodiments; for example, the cylinder device is not limited to a hydraulic cylinder but may also be an air cylinder. .

<Effects of the Invention> As described above, according to the present invention, since there is basically no need to provide a separate positioning device when used for moving a driven object, the device body can be made more compact, and Since the stop position of the cylinder rod can be directly adjusted, the excellent effect of reliably increasing the movement accuracy of the driven object is achieved.

That is, the cylinder casing is provided with a stroke adjustment device for the cylinder rod, and the accurate moving position of the driven object can be directly adjusted by adjusting the stroke of the cylinder rod. It has the advantage of eliminating the need for fine adjustments and increasing movement accuracy.

Furthermore, by arranging the stroke adjustment device internally in the cylinder casing, there is no drop in positioning accuracy due to external dust or other deposits, which is advantageous in terms of maintenance. Ru.

[Brief explanation of the drawing]

Figure 1.2 shows an embodiment of this invention, and shows the first embodiment.
FIG. 2 is a sectional view of the first embodiment, FIG. 2 is a schematic diagram of essential parts of the second embodiment, and FIG. 3 is a schematic diagram showing a conventional aspect. 19...Cylinder rod, 20...Piston, 1
8...Cylinder casing, 16.16'...Fluid input/output boat, 2'...Cylinder device, 23.25...Stroke adjustment device Applicant: Toyota Motor Corporation Toko Kogyo Co., Ltd.

Claims (1)

[Claims] In a cylinder device in which a piston having an integral cylinder rod is installed inside a cylinder casing so as to be able to slide forward and backward, and the cylinder casing is provided with a fluid inlet/output port, a stroke adjustment device for the cylinder rod is installed inside the cylinder casing. A cylinder device featuring: