JPH08210306A - Confirmation of hydraulic oil supply to operating cylinder and cell for the confirmation - Google Patents

Abstract

PURPOSE: To detect the operation of a hydraulically-operated operating cylinder at a position apart from the operating cylinder and without using mechanical linkages. CONSTITUTION: When hydraulic oil is fed to a cylinder chamber 54 on the front side of the piston 53 of a hydraulic oil supply confirmation cell 50A, the piston 53 moves from a front side stroke end to the rear side stroke end, and a detector 69 detects it. The hydraulic oil in a cylinder chamber 55 on the rear side is pushed out with the movement of the piston 53, and flows into the lower cylinder chamber 15b of positioning cylinders 10a, 10b, so that a positioning pin 12 is pushed up and fitted into a positioning hole. Unless the positioning pin 12 strokes by a prescribed amount, only a small amount of hydraulic oil can flows into the front side cylinder chamber 54. Therefore, the piston 53 does not reach a rear side stroke end, so it is possible to identify that, a prescribed amount of hydraulic oil has not been supplied to the positioning cylinders 10a, 10b.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the operation of a working cylinder, which is provided with a predetermined amount of working oil to detect whether or not the working cylinder has correctly operated through a fluid. The present invention relates to an oil supply confirmation method and a hydraulic oil supply confirmation cell.

[0002]

2. Description of the Related Art For example, a jig for fixing a work, which is provided in correspondence with a machining position of a machine tool, in a transfer machining line or the like for conveying a workpiece and performing a predetermined machining by a machine tool installed at a predetermined machining station. Then, the positioning pin 113 is connected to the tip of the piston rod 115 of the hydraulic cylinder (working cylinder) 100 provided in the jig,
The positioning pin 113 is engaged with and disengaged from the positioning hole of the work to position the work on the jig, and the positioning is released. In such a hydraulic cylinder 100, as shown in FIG. 6, in order to confirm whether or not the hydraulic cylinder 100 is accurately operated by a predetermined stroke and the positioning pin 113 is surely fitted into the positioning hole of the workpiece. A pressure switch 112 is provided in a pipe path 111 between the 100 and the hydraulic power source 110, and when the pressure set by the pressure switch 112 is reached, it is determined that the hydraulic cylinder 100 has fitted the positioning pin 113 into the positioning hole. , Move to the next operation, or directly detect the piston stroke of the hydraulic cylinder 100,
Alternatively, the stroke operation of the hydraulic cylinder is taken out of the jig body through a mechanical connection mechanism and detected by a limit switch or the like to detect that the hydraulic cylinder has moved a predetermined stroke. .

[0003]

SUMMARY OF THE INVENTION In the prior art,
In the case of using the pressure switch, when the positioning pin is fitted into the positioning hole, the hydraulic cylinder that has moved the positioning pin cannot detect any further stroke and detects the rising pressure. Therefore, the work is not fed to the jig at the specified position, the positioning pin does not fit into the positioning hole, and the positioning pin comes into contact with another part of the work, making it impossible to move further. Even if
Similar to the case where the positioning pin is correctly fitted, the hydraulic cylinder cannot make a stroke any more, and the pressure switch has a problem of detection error that detects the increase in pressure and determines that the hydraulic cylinder has normally operated. Also, in the case of directly detecting the piston stroke of the hydraulic cylinder, it is necessary to place a proximity switch, limit switch, etc. very close to the hydraulic cylinder, and when the hydraulic cylinder is placed deep in the jig, Are hard to reach by workers, and subsequent maintenance is extremely troublesome. If the piston stroke of the hydraulic cylinder is taken out by mechanical connection to the outside of the jig, the mechanism becomes complicated, the number of parts increases, and there is a problem that assembly and processing cost. An object of the present application is to provide a hydraulic oil supply confirmation method and a confirmation cell capable of detecting whether or not a hydraulically operated working cylinder has reliably stroked at a position distant from the operating cylinder without using complicated mechanical connection. It is in.

[0004]

[Means for Solving the Problems] In order to solve the above problems,
According to claim 1 of the present application, a detected body that is moved by the supply / discharge hydraulic oil to the operating cylinder is provided in the middle of the pipe between the hydraulic pressure source and one of the supply / discharge ports of the operating cylinder, and the movement of the detected body is performed. Is detected by a detector to detect whether or not a predetermined amount of hydraulic oil has been supplied to the operating cylinder. In the second aspect of the present invention, a hydraulic oil supply confirmation cell suitable for use in this method is such that a piston is axially movably fitted in a cylinder chamber provided in the cell body, and the cylinder chamber is provided with a front cylinder and a rear cylinder. A connection port that is divided into chambers and that communicates with each cylinder chamber in the cell body in correspondence with each cylinder chamber and is connected to one of the pair of supply / discharge ports of the operating cylinder and the hydraulic pressure source. In addition to providing a pair of, equipped with a detector that detects the stroke end before and after the piston,
The cylinder volume of this hydraulic oil supply confirmation cell is set so that the piston moves from one stroke end to the other stroke end by the hydraulic oil supplied and discharged when the operating cylinder makes a predetermined stroke. It is characterized by A third aspect of the present invention is characterized in that the detectors for detecting the front and rear stroke ends of the piston according to the second aspect are arranged so as to face the piston at positions on the cell main body that are axially forward and backward of the center of the piston.

[0005]

According to the first aspect of the present invention, when a predetermined amount of hydraulic oil is supplied to the operating cylinder without interruption, the object to be detected in the middle of the hydraulic pipe moves a predetermined stroke by the hydraulic oil supplied to and discharged from the operating cylinder. Also, when a predetermined amount of hydraulic oil is not supplied to the operating cylinder and the operating cylinder does not move for a predetermined stroke, the detected object also does not move for a predetermined stroke, and due to this stroke difference, a predetermined amount of hydraulic oil is supplied to the operating cylinder. Whether the operating cylinder has been ejected and moved normally,
In the middle of pressure piping, that is, at a position away from the working cylinder,
Detects without having mechanical connection with the working cylinder. Further, in claim 2, the cylinder volume of the hydraulic oil supply confirmation cell having the piston as the object to be detected is set such that when the operating cylinder makes a predetermined operating stroke, the piston in the cell body moves from one stroke end to the other. Move to the stroke end and check the hydraulic oil supply to the operating cylinder depending on whether it is located at this stroke end.
The cell itself does not have an extra cylinder volume, the cell itself can be downsized, and the piston is not detected at the intermediate position of the stroke, so the detection is reliable. Further, since it is configured as a hydraulic oil supply confirmation cell having a connection port, it can be connected to a pipe very easily like other hydraulic oil control devices such as a directional control valve and a relief valve. According to the present invention, since the detectors are arranged coaxially with each other in the axial direction of the piston, there is no protrusion on the side surface of the main body of the apparatus, and when a large number of hydraulic oil supply confirmation cells are arranged side by side, they can be arranged compactly and the mounting space Can be made smaller.

[0006]

EXAMPLE In FIG. 1, a bed 2 of a machine tool 1 is
A spindle head 4 is supported to be vertically movable on a column 3 that moves back and forth and to the left and right, and a tool 6 is attached to the tip of a spindle 5. A jig 8 for mounting and positioning the work 7 is fixed in front of the column 3. In the jig 8, the jig body 9
Is fixed on the bed 2, and a pair of positioning cylinders (shown as operating cylinders) 10a and 10b are attached to the jig body 9 from the lower surface side with the piston rod 11 facing upward. Positioning pins 12 that fit into and disengage from positioning holes 7a formed in the lower surface of the work 7 are fixed to the tips of the piston rods 11. As is well known, the one positioning pin 12 is a diamond pin and the other positioning pin 12 is a round pin. Positioning cylinder 10a,
The cylinder body 13 of the cylinder 10b is divided into upper and lower cylinder chambers 15a and 15b by the piston 14 which is integral with the piston rod 11, and the upper and lower cylinder chambers 15a and 15b of the cylinder body 13 correspond to the corresponding supply / discharge ports 16a. 1
It communicates with 6b. The cylinder capacity V of the lower cylinder chamber 15b when the piston 14 is at the upper stroke end (upward end) (when the positioning pin is completely fitted) is the same as when the piston 14 is at the lower stroke end (downward end). It is larger than the cylinder capacity of the upper cylinder chamber 15a by the volume of tightening the piston rod. In the present embodiment, this cylinder capacity V is the amount of hydraulic oil required for the positioning operation of the positioning cylinders 10a, 10b. The supply / discharge ports 16b are communicated with each other via a pipe 17, and the supply / discharge ports 16a are communicated with each other via a pipe 18. The pipe 17 is connected to the pipe 17A, and the pipe 17A is connected to the electromagnetic switching valve 19 via a hydraulic oil supply confirmation cell 50A, which will be described later, and to the oil tank T of the hydraulic power source 20. Piping 17, 17A
In this embodiment, is a supply-side pipe when the positioning pin 12 is inserted (when the positioning cylinders 10a and 10b are operated). The pipe 18 is connected to the pipe 18A and is connected to a hydraulic oil supply source (hydraulic pump) P of the hydraulic source 20 via an electromagnetic switching valve 19. The pipes 18 and 18A are supply-side pipes when the positioning pin 12 is removed (when the operation is released).

On the upper surface of the jig body 9, a plurality (here, a pair) of clamp cylinders (also a kind of operating cylinder) for clamping the work 7 in a positioned state are provided.
1 is stuck. Each clamp cylinder 21 also includes a pair of supply / discharge ports 22a and 22b.
a and the supply / discharge port 22b are connected to each other by pipes 23 and 24, and the pipe (clamping (during clamp cylinder operation) supply-side pipe) 23 has the hydraulic oil supply confirmation cell 50B and the electromagnetic switching valve 25 as described above. Further, the piping (supply side piping when unclamping (when the clamp cylinder operation is released) 24) is connected to the tank T and the hydraulic pump P via an electromagnetic switching valve 25, respectively. Supply / Discharge port 22a
Is a supply side port when the clamp cylinder 21 is clamped, and the supply / discharge port 22b is the clamp cylinder 21.
Is a supply side port at the time of unclamping, and the work 7 is clamped and unclamped by the clamp member 26 by supplying and discharging hydraulic oil from these supply / discharge ports 22a and 22b.

Next, the hydraulic oil supply confirmation cell 50A (50B) according to the present invention will be described. The cell 50A and the cell 50B have exactly the same structure except for the cylinder volumes, and therefore the cell 50A will be described. As shown in FIG. 2, the cell body 51 is configured by fixing an end member 51b to a right end of a cylinder barrel 51a having a rectangular (or round) cross section with a bolt 51c. A piston 53 as an object to be detected is fitted in a cylinder hole 52 provided at the center of the cell body 51 so as to be movable in the axial direction. The cylinder hole 52 is partitioned by the piston 53 into a front cylinder chamber 54 and a rear cylinder chamber 55. In the piston 53, a lid body 53b is integrally connected to a piston body 53a with a screw 56 (FIG. 3), and the piston body 53a and the lid body 53b are provided with a detected member 57 on the central axis thereof in the front and rear cylinder chambers 54, 55. It is configured to project inward and be attached integrally.
In the end wall 53c of the piston main body 53a and the lid 53b, two communicating holes 58 are formed on the upper and lower sides on the same straight line, and the piston main body 53a and the lid 53b are integrally connected.
A spring accommodating hole 59 is formed to communicate between the corresponding communicating holes 58.

A ball 60 acting as a valve is movably fitted in the spring accommodating hole 59, and one ball accommodating hole (upper side in FIG. 2) 59 is formed by the spring 61 provided in the spring accommodating hole 59. In the above, when the piston 53 is moving axially forward (to the left in FIG. 2), the ball 60 is pressed against the communication hole 58 of the lid 53b, and the piston 53 moves toward the front stroke end (see FIG. 2). 2) and cannot move forward (to the left in FIG. 2), the ball 59 is pushed by the force of the hydraulic oil supplied to the rear cylinder chamber 55 to move the hydraulic oil from the rear cylinder chamber 55 to the front part. It is adapted to flow into the cylinder chamber 54, and in the other spring accommodating hole (lower side in FIG. 2) 59, when the piston 53 is moving axially rearward (rightward in FIG. 2), the ball 60 The communication hole 5 of the end wall 53c When the piston 53 is located at the rear stroke end and cannot retract further (to the right in FIG. 2), the ball 59 is moved by the force of the hydraulic oil supplied to the front cylinder chamber 54. The hydraulic oil is pushed to flow from the front cylinder chamber 54 into the rear cylinder chamber 55, and thus the piston 53 is provided with a pair of check valves 65a and 65b. This check valve 6
5a and 65 also have a function of replenishing the amount of leak when there is a slight oil leak in the middle of piping.

Cylinder barrel 51a and end member 51b
The insertion holes 66a, 6 into which the detected member 57 is inserted when the piston 53 is located at the front and rear stroke ends.
6b and connection ports 67a and 67b are provided. The connection port 67a communicating with the front cylinder chamber 54 is connected to the hydraulic power source 20, and the connection port 67b communicating with the rear cylinder chamber 55 is connected to the positioning cylinders 10a, 10b.
Are connected to the supply / discharge port 16b via the pipes 17 and 17A, respectively. Also, the fitting holes 66a, 66b
A screw hole 68 is provided coaxially with the shaft center of the piston 53 on the front side and the rear side, respectively, leaving a predetermined wall pressure, and the piston 53 is located at the front and rear stroke ends in this screw hole 68. At this time, a detector 69 for detecting the detected member 57 is screwed in and fixed by a nut 70. Detector 6
9 is preferably a reed switch. A signal from the detector 69 is transmitted to a control device (not shown) via a signal line 71. A mounting plate 72 having the same width as that of the cylinder barrel 51a is fixed to the lower surface of the cylinder barrel 51a, and a mounting hole 73 is formed in the mounting plate 72.

In the cell 50A for the positioning cylinders 10a and 10b, the cylinder volumes of the front and rear cylinder chambers 54 and 55 are two cylinders 10a and 10b.
Piston 14 rises by a predetermined stroke from its descending end (state of FIG. 5A), and the amount of hydraulic oil required for the positioning pin 12 at the tip to be completely fitted into the positioning hole 7a (fitting operation of the positioning pin 12) Direction hydraulic oil amount), and is set to be slightly smaller than that of the piston 14 as in the present embodiment.
When the positioning pin 12 is completely fitted at the rising end of the cylinder, the sum of the cylinder volumes V of the lower cylinder chamber 15b (2
V), and is set to be slightly smaller than V), for example, about 90% (1.8 V) which is twice the cylinder volume V. The degree of this setting is such that the positioning pin 12 has not been completely inserted into the positioning hole 7a, but has been almost inserted into the positioning hole 7a, and thereafter, the positioning pin 12 is located up to a position where no fitting error occurs. This corresponds to the amount of hydraulic oil required to make 12 stroke. By setting in this way and by the action of the check valves 65a and 65b, the pistons 14 of the positioning cylinders 10a and 10b have a predetermined stroke required for the inserting operation of the positioning pin 12 (in this embodiment, from the lower end to the upper end). Up to the stroke end on the front side (see FIG. 5).
(A)) to the rear stroke end (FIG. 5 (b)), and the predetermined stroke required for the removal operation of the positioning pin 12 (from the rising end of the piston 14 to the falling end). (Movement of) causes the piston 53 to move from the rear stroke end (FIG. 5B) to the front stroke end (FIG. 5).
It can be surely moved to (a)).

Even if the cylinder volume of the cell 50A is made larger than the sum (2V) of the amount of hydraulic oil required for the fitting operation of the positioning pins 12 of the positioning cylinders 10a and 10b,
Although it is possible to implement the method of the present application by detecting the intermediate position of the piston 53, as described above, from the amount of hydraulic oil required for the operation of the positioning cylinders 10a, 10b,
By setting the cylinder volume of the cell 50A to a slightly smaller cylinder volume, it is possible to avoid giving the cell 50A an extra cylinder volume, and the cell 50A can be downsized.
Regarding the cell 50B, the cylinder volume of the cell 50B corresponds to the amount of hydraulic oil required to perform the clamp operation of the clamp cylinder, and the piston as the detected object in the cell 50B moves from one stroke end to the other stroke. The only difference is that it is set to move to the edge.

Such hydraulic oil supply confirmation cells 50A, 5
OB is the positioning cylinders 10a and 10b as described above.
Alternatively, the cells 50A and 50B have a rectangular outer shape and a detector 69 projecting forward and backward in the axial direction of the cell body 51. As shown in 4, they can be placed next to each other and do not take up mounting space. Moreover, because it is an independent form called a cell, like other hydraulic control equipment,
It is extremely easy to connect in the middle of piping, and it can be installed at a place away from the operating cylinder.

Next, the operation of the hydraulic oil supply confirmation cell 50A will be described. The piston 14 of each of the positioning cylinders 10a and 10b is at the lower end and the positioning pin 12 is retracted. At this time, the piston 53 of the cell 50A is located at the front stroke end, as shown in FIG. From this state, the electromagnetic switching valve 19 is switched to supply the hydraulic oil from the hydraulic pump P to the front cylinder chamber 54 of the cell 50A via the pipe 17A.
As a result, the piston 53 starts moving rearward from the front stroke end. By the backward movement of the piston 53, the hydraulic oil in the rear cylinder chamber 55 is pushed out, flows into the lower cylinder chamber 15b of the positioning cylinders 10a, 10b via the pipes 17A, 17 and the supply / discharge port 16b, and lowers the piston 14. Push up from the edge.

When the pistons 14 of the positioning cylinders 10a and 10b operate normally and the amount of hydraulic oil supplied from the hydraulic pump P reaches 1.8 V, the piston 53 of the cell 50A is positioned at the rear stroke end and the positioning is performed. Cylinder 10
The piston 14 of a, 10 moves 90% of the stroke from the lower end to the upper end, and the positioning pin 1
2 is almost inserted into the positioning hole 7a of the work 7, and the detector 69 on the rear side is the detected member 57 on the rear side of the piston 53.
Of the positioning cylinders 10a, 10
The normal operation detection signal of b is output. Positioning pin 12
Has not yet been completely inserted into the positioning hole 7a, but the positioning pin 12 is almost fitted into the positioning hole 7a,
Since no fitting error will occur thereafter, there is no problem even if the motion detection signal is output immediately before the positioning pin 12 is completely fitted in this way. Further, hydraulic oil is sent out from the hydraulic oil pump P and flows into the front cylinder chamber 54 of the cell 50A. Since the piston 53 is located at the rear stroke end and cannot move, the supplied oil pushes back the ball 60 of the lower check valve 65b against the force of the spring 61, and the lower communication passage in FIG. 58, the spring accommodating hole 59, the connection port 67b, the supply / discharge ports 16b of the positioning cylinders 10a, 10b, and the lower cylinder chamber 15b. As a result, when the piston 14 is further pushed up and the hydraulic oil of the oil amount V is supplied to the lower cylinder chambers 15b of the positioning cylinders 10a and 10b, the positioning pin 12 is completely fitted into the positioning hole 7a. The positioning of the work 7 is completed. Then, the clamp cylinder 21 acts, and the working oil is supplied via the cell 50B to clamp the work 7, similarly to the positioning cylinders 10a and 10b.

The supply state of the work 7 onto the jig 8 is poor, and the positioning hole 7a and the positioning pin 12 are misaligned so that the positioning pin 12 does not fit into the positioning hole 7a and the lower surface of the work 7 When the piston cannot reach the fitting position, the piston 14 does not reach the rising end even if the working oil is supplied to the front cylinder chamber 54 of the cell 50A. Therefore, the amount of oil discharged from the rear cylinder chamber 55 is reduced. 1.8V
Therefore, since the piston 53 of the cell 50A does not reach the rear stroke end, the detector 69 cannot detect the detected member 57 of the piston 53. Therefore, after switching the electromagnetic switching valve 19, Since the normal operation detection signal is not output even after the lapse of a predetermined time, the positioning cylinder 10
It can be seen that a predetermined amount of hydraulic oil was not supplied to a and 10b, causing a malfunction.

Next, when the positioning pin 12 is removed, hydraulic oil is supplied to the upper cylinder chamber 15a of the positioning cylinders 10a and 10b via the pipes 18A and 18,
The piston 14 moves from the rising end toward the falling end.
As a result, when a total of 1.8 V of hydraulic oil is discharged from the lower cylinder chamber 15b of both positioning cylinders 10a and 10b to the rear cylinder chamber 55 of the cell 50A, the piston 53 of the cell 50A moves to the rear stroke. From the end to the front stroke end, the detector 69 on the front side of the cell 50A is
The member to be detected 57 is detected and the removal operation of the positioning pin 12 is confirmed. After that, the upper check valve 65 in FIG.
When the hydraulic oil is discharged via a and the total discharged oil amount becomes 2V, the piston 14 reaches the lower end. Even when the removal operation is defective, the amount of discharge from the lower cylinder chamber 15b is insufficient as in the case of fitting, so that the piston 53 of the cell 50A does not reach the front stroke end. Therefore, the detector 69 on the front side (the left side in FIG. 2) cannot detect the member to be detected 57 on the front side of the piston 53, and thus the malfunction can be recognized.

The embodiments understood from the examples of the present application will be described below. (a) Set the cylinder volume of the hydraulic oil supply confirmation cell to be slightly smaller than the flow rate required for the operating cylinder to make a predetermined stroke in the operating direction, and to the piston, connect a pair of front and rear cylinder chambers. Check valve, one check valve allows the flow of fluid from the front cylinder chamber to the rear cylinder chamber, and the other check valve
3. The structure according to claim 2, wherein the fluid is allowed to flow from the front cylinder chamber into the rear cylinder chamber.
The hydraulic oil supply confirmation cell described. (b) There are multiple operating cylinders, each operating cylinder is connected in parallel to the hydraulic source, and the cell cylinder volume is set to be slightly smaller than the sum of the cylinder volumes of the multiple operating cylinders. The hydraulic oil supply confirmation cell according to (a), wherein

[0019]

As described above, according to claim 1 of the present invention, it is determined whether or not a proper amount of hydraulic oil is supplied to the operating cylinder in the middle of the pipe connecting the operating cylinder and the hydraulic pressure source. Since it is detected through the detected object that moves due to the supply of oil, the supply of hydraulic oil to the operating cylinder can be confirmed at a position in the middle of the piping path that is far from the operating cylinder, and the operating cylinder is located deep inside various devices such as jigs. Even in the
The operation of the operating cylinder can be reliably confirmed without malfunction without using complicated mechanical connection. Further, in claim 2, the cylinder volume of the hydraulic oil supply confirmation cell having the piston as the object to be detected is set such that when the operating cylinder makes a predetermined operating stroke, the piston in the cell body moves from one stroke end to the other. By moving to the stroke end and checking the hydraulic oil supply to the operating cylinder depending on whether it is located at this stroke end, there is no extra cylinder volume in the cell body, and the cell itself can be downsized,
Moreover, since the piston is not detected at the intermediate position of the stroke, the detection is reliable. Further, since it is configured as a hydraulic oil supply confirmation cell having a connection port, it can be connected to a pipe very easily like other hydraulic oil control devices such as a directional control valve and a relief valve. Further, in claim 3,
Since the detectors are coaxially arranged in the axial direction of the piston, there are no protrusions on the side surface of the device body, and when many hydraulic oil supply confirmation cells are installed side by side, they can be arranged compactly and space can be saved. it can.

[Brief description of drawings]

FIG. 1 is a view showing a jig device to which a hydraulic oil supply confirmation cell of the present application is applied.

FIG. 2 is a cross-sectional view of a hydraulic oil supply confirmation cell.

3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a perspective view showing a mounted state of a hydraulic oil supply confirmation cell.

FIG. 5 is an operation explanatory diagram of a hydraulic oil supply confirmation cell.

FIG. 6 is a conventional technique.

[Explanation of symbols]

10a, 10b Positioning cylinder (operating cylinder),
16a, 16b supply / discharge port, 17, 17A, 18, 1
8A piping, 20 hydraulic power source, 50A, 50B hydraulic oil supply confirmation cell, 51 cell body, 53 piston (object to be detected), 54 front cylinder chamber, 55 rear cylinder chamber, 65a, 65b check valve, 67a, 67b
Connection port, 69 detector

Claims (3)

[Claims] 1. An object to be detected which is moved by supply / discharge hydraulic oil to the operating cylinder is provided in the middle of a pipe between a hydraulic pressure source and one of the supply / discharge ports of the operating cylinder, and the movement of the object to be detected is detected. A method for confirming the supply of hydraulic oil to an operating cylinder, characterized by detecting whether or not a predetermined amount of hydraulic oil has been supplied to the operating cylinder. 2. A working oil supply confirmation cell for a working cylinder, which is interposed in the pipe path between a hydraulic pressure source and one of the supply / discharge ports of the working cylinder, and which is provided in a cylinder chamber provided in the cell body. The piston is fitted so as to be movable in the axial direction, and the cylinder chamber is partitioned into a front cylinder chamber and a rear cylinder chamber, and the cell body communicates with each cylinder chamber in correspondence with each cylinder chamber. Cylinder volume of this hydraulic oil supply confirmation cell is provided with a pair of supply / discharge ports of one of the pair of supply / discharge ports and a connection port connected to the hydraulic pressure source, and a detector for detecting the stroke end before and after the piston. Is set so that the piston moves from one stroke end to the other stroke end by hydraulic oil supplied and discharged when the operating cylinder makes a predetermined stroke. Cell for checking hydraulic oil supply to working cylinder. 3. A detector according to claim 2, wherein a detector for detecting a stroke end before and after the piston is arranged opposite to the piston at a position on the cell main body, which is in the axial front and rear of the center of the piston. Cell for confirming hydraulic oil supply to operating cylinder.