JPH0584671A - Chuck device - Google Patents

Abstract

PURPOSE:To release gas of increased pressure to the outside by providing a holding member, which holds a doughnut-shaped internal periphery of an elastic unit and has a discharge hole opened to both sides in an axial direction of this elastic unit to connect closed space in a chucked workpiece to the outside, and a discharge circuit connected to an outside opening end of the discharge hole. CONSTITUTION:By lowering down a lift table 41, a chuck device 40 is inserted to drums 21 vertically arranged on a table 43, and next, compressed air is supplied to an elastic unit 22 inflated to hold the drum 21. The lift table 41 is lifted, and the drum 21 is conveyed to a tank 42 by a horizontally moving table 44. Here, the lift table 41 is lowered down to compress gas in the drum 21, and the rise of this pressure is detected by a pressure switch 33. On the other hand, when the rise of pressure is detected by all the chuck devices 40, a valve 34 is opened to release the gas in each drum 21 to the outside.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chuck for a cylindrical work, such as an organic photosensitive drum, which is made of an elastic material capable of expanding and contracting.

[0002]

2. Description of the Related Art A conventional chuck will be described below.

FIG. 3 is a sectional view of a conventional chuck, and FIG. 4 is a schematic view of a coating apparatus for coating a drum. In FIG. 3, 1 is a drum. Reference numeral 2 denotes an elastic body capable of expanding and contracting to hold the inner circumference of the drum 1. A holding member 3 holds an elastic body, and an air hole 4 for supplying compressed air to the elastic body 1 is opened. Reference numerals 5 and 6 are guides for gripping the drum 1. 7
Is a rotary shaft connected to the holding member 3 at one end, and has a through hole for supplying compressed air. Reference numeral 8 denotes a housing that supports the rotating shaft 7 with bearings 9 and 10. In FIG. 4, 11
Reference numeral 12 is a chuck configured as shown in FIG. 3, and 12 is a lifting table to which a plurality of chucks are fixed and which moves vertically.
3 is a tank containing the coating liquid. Reference numeral 14 is a table for delivering the drum 1, and reference numeral 15 is a photoelectric sensor for detecting the presence or absence of the drum 1. Reference numeral 16 is a horizontal movement table that conveys the drum from the table 14 to the tank 13.

The operation of the chuck constructed as above will be described below. First, the elastic bodies 2 are inserted into the drums 1 which are vertically arranged on the table 14, and the elastic bodies 2 expand to grip the drums 1. After it is confirmed by the optical sensor 15 that the chuck 11 has grasped all the drums, the table 16 enters the tank 13, and then the table 12 is raised at a low speed to finish the coating.

[0005]

However, in the chuck device having the above structure, only the lower end of the portion of the drum 1 below the elastic body 2 is opened when the drum 1 is gripped by the elastic body 2, and the closed space is formed. Becomes Therefore, when the drum 1 enters the coating liquid, the air in the drum is once compressed, and when the drum 1 rises, the compressed air becomes bubbles and is discharged from the drum 1 into the coating liquid. To be done.
The vaporized product of the solvent contained in the coating liquid may be similarly released. The air bubbles thus released remain as voids in the coating film, and have the drawback of causing defects. Further, the drum 1 is the chuck 11
It is grasped by the optical sensor 15 that the table 14
Check above, but if there are many drums, chuck 1
Since it is confirmed for each row that the drum 1 does not remain on the table 14 when 1 is lifted, there are not enough drums on the table 14 before the chuck 11 catches the drum. In that case, it cannot be recognized that there is a specific chuck that does not grip the drum. In addition, even if the drum is dropped while being conveyed to the tank 13, it cannot be confirmed. In any case, the chuck not holding the drum is directly immersed in the coating liquid and the elastic body 2 becomes the coating liquid. It has a problem that it may be damaged or dust may enter the coating liquid.

The present invention solves the above-mentioned conventional problems by detecting the pressure of the gas in the drum during coating,
An object of the present invention is to provide a chuck device capable of discharging gas in the drum to the outside through the chuck during coating and confirming that the chuck holds the drum during coating.

[0007]

In order to achieve this object, a chuck device of the present invention holds an inflatable donut-shaped elastic body, the elastic body and the inner periphery of the donut shape, and A holding member having an exhaust hole that opens to the outside a sealed space in the workpiece that is opened on both sides in the axial direction with respect to the body, an exhaust circuit connected to the external opening end of the exhaust hole, and an exhaust circuit Each is equipped with a pressure switch provided on the way.

[0008]

When the drum enters the coating liquid, the pressure switch detects an increase in pressure inside the drum. If the pressure does not increase at that time, it is recognized that the chuck is not gripping the drum, and if the pressure exceeds a predetermined set value, the compressed gas in the drum is discharged to the outside through the chuck.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of a chuck device according to an embodiment of the present invention. FIG. 2 is a perspective view of a coating machine for coating a drum using the chuck device of the present invention. In FIG. 1, 21 is a drum, which is a cylindrical work, and 22 is an elastic body that holds the inner circumference of the drum 21.
Reference numeral 23 is a holding member that holds the inner periphery of the elastic body 22 in the shape of a donut, and an air hole 24 for supplying compressed air to the elastic body 22 and an exhaust gas whose one end a communicates with a space below the grip portion in the drum 21. A hole 25 is provided, and the other end of the exhaust hole 25 communicates with the elastic body to the outside on the side opposite to a. That is, the exhaust holes 25 are open to the elastic body 22 on both sides in the axial direction, one end of the exhaust hole 25 communicates with the sealed space below the grip portion, and the other end of the exhaust hole 25 communicates the sealed space with the outside. There is. Reference numerals 26 and 27 are guides for inserting the elastic body 22 into the drum 21. An exhaust hole 28 that is connected to the exhaust hole 25 is formed in the upper guide 7. Reference numeral 29 is a connecting member for connecting the pipe 31 and the exhaust hole of the guide 27 with the exhaust hole 32, and is rotatably held with the guide 27. The exhaust holes 28 and 32 and the pipe 31 form an exhaust circuit. Reference numeral 33 is a pressure switch as a pressure detecting means installed in the middle of the pipe 31. Three
Reference numeral 4 is a valve connected to the pipe 31. A rotary shaft 35 is connected to the holding means 23 at one end and has a through hole 36 for supplying compressed air. 37 is a bearing 38, 39
The housing supports the rotary shaft 35, and the connecting member 29 is fixed to the lower end of the housing. In FIG. 2, 40 is the same as in FIG.
The chuck device is configured as follows. Reference numeral 41 is an elevating table with a plurality of chuck devices fixed for vertical movement, 42 is a tank containing the coating liquid, 43 is a table for delivering the drum 21, and 44 is a horizontal table for transporting the drum from the table 43 to the tank 42. It is a moving table.

The operation of the chuck device constructed as above will be described below. As the lifting table 41 descends, the chuck device 40 is inserted into the drum 21 placed upright on the table 43, compressed air is then supplied to the elastic body 22, and the elastic body 22 expands to grip the drum 21. To do. The elevating table 41 moves up, and the drum 21 is conveyed to the tank 42 by the horizontal moving table 44. The elevating table 41 descends here, and the drum 2
When 1 is in the coating liquid to some extent, the gas in each drum 21 is compressed, and the pressure switch 33 detects this pressure increase. At this time, if there is a chuck device 40 in which the increase in pressure is not detected, it means that the chuck device 40 does not grip the drum 21, and the lifting table 41 immediately rises. On the other hand, if a pressure increase is detected in all the chuck devices 40, the valve 34 is opened at this point to discharge the gas in each drum 21 to the outside. The elevating table 41 continues further descending, and when the pressure inside each drum 21 rises, the valve 34 operates again to discharge the gas inside each drum 21 to the outside. After that, the lifting table 41 is raised at a low speed to form a coating film on the drum 21. Rotation is applied to the drum 21 when rising so that the coating film has a uniform film thickness.

In the above embodiment, a path for supplying compressed air is provided in the middle of the exhaust circuit, and when the chuck device 41 holds the drum 21 on the table 43, the compressed air is sent to the drum 21 through this exhaust circuit. For example, the lower end opening of the drum 21 on the table 43 is the table 4
3 Since the inside is closed because it is closed on the surface, the internal pressure rises and the presence of the drum can be detected. Without the drum 21, of course, such a pressure increase does not occur, so that the absence of the drum can also be detected.

Although the chuck device of this embodiment has a structure in which the drum can rotate, it can be applied to a chuck device in which the drum does not rotate.

[0014]

As described above, according to the present invention, an inflatable donut-shaped elastic body and a donut-shaped inner circumference of the elastic body are held, and the elastic body is opened and gripped on both axial sides thereof. By providing a holding member having an exhaust hole for communicating the closed space in the work to the outside, an exhaust circuit connected to the outer opening end of the exhaust hole, and a pressure switch provided in the middle of the exhaust circuit. It is possible to realize a chuck device that can detect the pressure increase of the gas in the drum, can detect the presence or absence of the drum, and can discharge the gas whose pressure has increased to the outside.

[Brief description of drawings]

FIG. 1 is a sectional view of a chuck device according to a first embodiment of the present invention.

FIG. 2 is a perspective view of the same.

FIG. 3 is a sectional view of a conventional chuck device.

FIG. 4 is a perspective view of the same.

[Explanation of symbols]

 21 drum 22 elastic body 23 holding member 25 exhaust hole 31 pipe 33 pressure switch

Claims (1)

[Claims] 1. A chuck device for gripping a cylindrical work, comprising a donut-shaped elastic body capable of expanding and contracting, a donut-shaped inner circumference of the elastic body, and a shaft thereof relative to the elastic body. A holding member having an exhaust hole that opens on both sides in the direction and communicates the enclosed space in the gripped work with the outside, an exhaust circuit connected to the external opening end of the exhaust hole, and provided in the middle of the exhaust circuit. A chuck device comprising a pressure switch, respectively.