JPH054099U - Movable slitting device - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent the irradiated object from staying in the slit part of the shield. A movable slit 13 for loading and unloading the irradiation target 3 is formed in the opening 10 of the shield 1 by the movable shield plate 11 and the fixed shield plate 12. The movable shield plate is rotatably attached to the attachment plate 15 by the rotation shaft 14 and the bearing 16. When the tip of the irradiated object floats up and hits the movable shield plate due to the flow of atmospheric gas passing through the slit when the conveyor device 4 such as a belt conveyor passes through the slit, the movable shield plate is pushed and rotated. To do. The slit becomes larger and the irradiation target can pass through. It is possible to prevent the irradiation target from accumulating in the slit, and prevent a failure of the transport device due to the accumulation.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a movable slit device for a radiation shield, particularly a movable slit device in an electron beam irradiation device.

[0002]

[Prior Art]

 The electron beam irradiator is configured so that the X-rays generated inside it are shielded by a shield so that the X-rays generated inside do not leak outside. It goes through the lit. FIG. 3 shows a cross-sectional view of such a shield part. A slit 2 is formed in a shield 1 made of lead or a reinforcing material such as lead and iron, stainless steel, and the like. The irradiation object 3 is placed on a conveyor device 4 such as a belt conveyor that moves in the direction of the arrow, and conveys and passes through the slit 2 of the shield 1. Such a shield 1 serves as a protective wall for preventing leakage of X-rays and scattered electron beams from the irradiation chamber and the preliminary chamber in the electron beam irradiation device, or is arranged in the irradiation chamber and the preliminary chamber to protect the X-rays and scattered electron beams. It is used as a means for attenuation and multiple reflection attenuation.

[0003]

[Problems to be solved by the device]

 By the way, the slit 2 provided in the shield 1 has a width as narrow as possible so that direct leakage of radiation such as X-rays is small. Therefore, the irradiation target 3 is transferred by the transfer device 4. When passing through the slit 2, some influence, for example, exhaust of ozone generated in the irradiation chamber at the time of electron beam irradiation, or atmospheric gas accompanying the supply of an inert gas to the irradiation chamber to reduce the oxygen concentration is generated. Under the influence of the flow, there may occur a situation in which the tip end portion of the irradiation target object 3 is lifted, caught in the slit 2, and clogged. Since the irradiation object 3 continues to be conveyed by the conveying device 4, the occurrence of such a situation then causes the state a of the irradiation object 3 to be rolled up in the slit portion as shown in FIGS. In the case of the irradiated object 3 whose thickness reaches, for example, several millimeters to 1 cm due to the fact that the transportation of 3 is disabled and the transportation device 4 is overloaded, at worse, at point b in FIG. 5, for example. As shown in the figure, this may cause damage or failure such as cutting of the belt in the transport device 4. Normally, the irradiation object 3 is conveyed at a high speed, and such entrainment occurs in an instant. In this respect, even if the entrained state is detected by using the photoelectric means or the like, it does not solve the entrained state by itself, and if the carrier device 4 is made to respond to the signal from the photoelectric detector means, it is Even if it can be escaped from a failure, the rolled-in part still exists in the slit part before, and in the place where the electron beam irradiation device is used as the production means, the production will eventually be stopped.

According to the present invention, by making the slit portion of the shield 1 through which the irradiation target 3 passes through a movable structure, even if the irradiation target 3 floats up, the irradiation target passes through and the irradiation at the slit part is performed. An object of the present invention is to provide a movable slit device capable of preventing the accumulation of substances.

[0005]

[Means for Solving the Problems]

 The present invention is characterized in that the slit portion of the shield through which the object to be irradiated is conveyed has a movable slit structure using a rotatable movable shield plate.

[0006]

[Action]

 When the tip of the irradiation target floats up and hits the movable shield plate when passing through the slit of the irradiation target object, the movable shield plate is pushed open by the tip end and the irradiation target object can be passed. Therefore, the occurrence of the rolled-in state of the irradiated object is suppressed, and even if the rolled-in state occurs, the movable shielding plate is pushed open at a point of a small state, and the irradiated object can pass through the slit portion.

[0007]

【Example】

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a front view of a right half portion from the center of the movable slit portion provided in the shield, and FIG. 2 is a sectional view of the movable slit portion taken along the line AA in FIG. The shield 1 made of a lead material or a two-layer material of lead and reinforcing iron and stainless steel is provided with a large opening 10 for carrying in and out the irradiation target 2. Adjacent to the opening 10, a movable slit portion is formed that forms a slit that allows the irradiation target 4 to pass therethrough. The slit portion includes a movable shield plate 11 and a fixed shield plate 12. A slit 13 is formed between the end portions of both shield plates. The movable shield plate 11 is composed of two layers of a lead plate 11 ₁ and a reinforcing plate 11 _{2 made} of stainless steel or the like, and the fixed shield plate 12 is also composed of a lead plate 12 ₁ and a reinforcing plate 12 ₂ . A rotary shaft 14 is fixed to both ends of the movable shield plate 11, and the rotary shaft 14 is rotatably supported by bearings 16 installed on a mounting plate 15, and the movable shield plate 11 is indicated by a chain line in FIG. As shown, it can rotate about the axis of the rotating shaft 14. The mounting plate 15 is fixed to the shield 1 with bolts 17, and the mounting hole 18 of the mounting plate 15 is formed into a long hole, and the width of the slit 13 can be adjusted according to the thickness of the irradiation target 4. As described above, the mounting position of the mounting plate 15 with respect to the shield 1 is adjustable as shown by the arrow and dotted line in FIG. The fixed shield plate 12 is attached and fixed to the attachment plate 19 fixed to the shield 1 with bolts 20.

A limit switch 21 such as an electromagnetic type or photoelectric type proximity switch or a micro switch is provided to detect the rotation of the movable shield plate 11, and its fixed portion 21 ₁ is fixed to the mounting plate 15. The movable portion 21 ₂ is attached to the movable shield plate 11 via the switch attachment plate 22. The output of the limit switch 21 is given to notifying means (not shown) and drive control means of the conveyance device 4.

In FIG. 2, when the object to be irradiated is conveyed and introduced into the slit 13 by the conveying device 4 from the right side of the shield 1, ozone is exhausted from the left side of the shield or an inert gas. When the tip of the irradiation target floats up and hits the movable shield plate 11 due to the flow of the atmospheric gas accompanying the supply of the gas, the movable shield plate 11 is pushed by the irradiation target to rotate, and the width of the slit 13 is increased. Is substantially increased, the irradiation target pushes the movable shield plate 11 open, and passes through the slit 13. Even when the rolled-in state occurs momentarily due to high-speed transportation of the irradiated object, the rolled-in portion pushes open the movable shield plate 11 and allows the irradiated object to pass therethrough before the convoluted state becomes large. The rotation of the movable shield plate 11 is detected by the limit switch 21 and displayed by the notifying means (not shown). When the rotation of the movable shield plate 11 continues for a predetermined time or longer, the drive control means of the conveyor device 4 (not shown) In response to the output of the limit switch 21, the operation of the carrier device 4 is stopped and the malfunction of the device is prevented.

Regarding attachment of the fixed shield plate 12 of the movable slit portion, the attachment plate 19 may be omitted and the fixed shield plate 12 itself may be omitted by omitting the fixed shield plate 12 itself. The movable slit portion may be formed by the body 1 (the lower portion of the shield 1 in FIG. 2).

[0011]

[Effect of the device]

 Since the present invention is configured as described above, when the tip of the irradiated object rises up and hits the movable shield plate when passing through the slit of the irradiated object, the movable shield plate is pushed open and rotated by this tip part. However, it is possible to pass the irradiation target, thus suppressing the occurrence of the entangled state of the irradiation target and moving the irradiation target at the time when the small entanglement condition occurs even if the entanglement condition occurs. Since the shielding plate can be pushed open to pass through, it is possible to prevent the phenomenon of staying of the irradiated part in the slit part, prevent the overload condition of the transport device, and eventually the occurrence of failure, and prevent damage in advance.

[Brief description of drawings]

FIG. 1 is a front view of an embodiment of the present invention.

FIG. 2 is a sectional view of an example.

FIG. 3 is a sectional view of a conventional slit portion.

FIG. 4 is an explanatory diagram of occurrence of a winding state of a tip of an irradiation target object in a slit portion.

FIG. 5 is an explanatory diagram of a state in which the leading end of the irradiation target object in the slit portion is rolled up.

[Explanation of symbols]

 1 Shield 3 Irradiation object 4 Conveyor 11 Movable shield 12 Fixed shield 13 Slit 14 Rotating shaft 15 Mounting plate 16 Bearing

Claims (1)

Claims for utility model registration: Claim 1. A movable slit device, wherein a rotatable movable shield plate is installed in an opening of a shield through which an object to be irradiated is conveyed.