JPH0555012U - Thickness gauge safety device - Google Patents

Abstract

(57) [Abstract] [Purpose] A shutter that blocks radiation is provided on the side that emits radiation, and if a shift in the upper and lower heads is detected, the shutter is closed and the drive motor is stopped to improve device safety. Let [Structure] In a device for measuring the thickness of an upper and lower head, which are arranged to face each other with the object to be measured sandwiched between them, the upper and lower heads (1, 2) are engaged with each other. Synchro belt (3), shutter mechanism (4) provided on the radiation emitting side head to block radiation emission, and overload detection to detect that the upper and lower heads are overloaded more than a set value Means (5), a drive motor (7) for driving the synchro belt, and a sequence circuit (8) for controlling the shutter mechanism and the drive motor based on a signal from the overload detection means.

Description

[Detailed description of the device]

[0001]

[Industrial application]

 The present invention relates to safety in use of a thickness gauge including a structure using radiation, and more specifically, the upper and lower detectors (upper and lower heads) configured to use radiation are used to connect the upper and lower heads. When measuring the thickness of the moving target (sheet-like substance), if there is a gap between the upper and lower heads, the shutter is automatically closed to reduce the leakage dose equivalent to ensure the safety of the device. It is related to a safety gauge safety device.

[0002]

[Prior Art]

 Conventionally, there are various types of thickness gauges, from contact type to infrared ray transmission type. Among them, the general technical contents of radiation thickness gauges are, for example, Japanese Utility Model Publication No. 59-166110. ..

In this conventional apparatus, the upper and lower heads, which are arranged facing each other with a mutual gap of 8 to 50 mm, run horizontally, so that the upper and lower heads are locked to the synchro belt. Then, the synchro belt is driven by the drive motor, so that the upper and lower heads travel left and right.

When an overload is applied to the drive motor, the drive motor is stopped, and if a displacement occurs in the upper and lower heads, the target is set based on a signal from a proximity switch attached to one of the upper and lower heads. It is designed to be evacuated. This is because radiation is used, and if the upper and lower heads are displaced, the leakage dose equivalent increases and this is avoided.

[0005]

[Problems to be solved by the device]

 However, in such a conventional technique, when the gap between the upper and lower heads is wide, it becomes unusable (the target cannot be evacuated) due to the distance between the proximity sensors. There was a point.

The present invention has been made in view of the above conventional problems, and an object of the present invention is to provide a shutter mechanism for blocking the radiation on the side that radiates the radiation so that the vertical head shifts. When the above is detected, the thickness gauge safety device is designed to close the shutter of the shutter mechanism and stop the drive motor to stop the upper and lower heads on the spot, thereby improving and maintaining the safety of the device. Is provided.

[0007]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the present invention provides a device for measuring the thickness of an upper and lower head, which is arranged to face each other with a measured object in between, by moving the upper and lower heads left and right on the measured object. Synchro belts (3) locked by (1, 2) respectively, a shutter mechanism (4) provided on the head that emits radiation to block radiation emission, and an overload above the set value on the upper and lower heads. Overload detection means (5) for detecting that the shutter is applied, a drive motor (7) for driving the synchronous belt, and the shutter mechanism and the drive motor are controlled based on a signal from the overload detection means. It is characterized by comprising a sequence circuit (8).

[0008]

[Action]

 In the present invention, an overload detecting means for detecting that the upper and lower heads are overloaded more than a set value (specifically, in the present invention, the upper and lower heads are locked in order to move the upper and lower heads left and right respectively. The synchro belt is a slip mechanism that disengages when the torque exceeds a certain level and slips. This is referred to below), and a signal from this slip mechanism, that is, a switch that operates by detecting the displacement at that time. And a sequence circuit that controls the operation of the drive motor that drives the synchro belt and the shutter mechanism that is installed in the head that emits radiation by the signal from this switch mechanism and that blocks the radiation of radiation. Let

Thus, when the slip mechanism causes a displacement of the upper and lower heads, that is, an overload of a set value or more, the shutter of the shutter mechanism is closed and the drive motor is stopped to stop the upper and lower heads on the spot. Let Therefore, even if the upper and lower heads are misaligned, the leakage dose equivalent is prevented from increasing, and the safety of the device can be maintained.

[0010]

【Example】

 Examples will be described with reference to the drawings.

FIG. 1 is a diagram showing a specific embodiment of the present invention.

In FIG. 1, 1 and 2 are upper and lower heads. The upper and lower heads are locked to the synchro belt 3, respectively. The sheet-like substance S, which is the object to be measured, runs between the upper and lower heads. The upper and lower heads 1 and 2 travel above and below the sheet material S by the synchro belt 3 to the left and right.

Reference numeral 4 denotes a shutter mechanism provided on a head that radiates radiation (herein referred to as a lower head 2) to block radiation.

Reference numeral 5 denotes a slip mechanism including, for example, a torque limiter. The upper and lower heads are misaligned when the sheet-like substance S being measured is cut off or hit by an operator during maintenance or the like and is overloaded. If the torque due to this deviation exceeds a certain set value, the engagement of the torque limiter will be dislocated and the slip operation will occur.

Reference numeral 6 denotes a switch mechanism composed of, for example, a limit switch that operates by detecting displacement during the slip operation (head displacement detection), that is, utilizing displacement when the meshing of the torque limiter 5 is displaced.

Reference numeral 7 denotes a drive motor that drives the synchro belt 3 to move the upper and lower heads 1 and 2 to the left and right, for example, a motor with a speed reducer.

A sequence circuit 8 inputs a signal from the switch mechanism 5 and outputs a control signal for controlling the operations of the shutter mechanism 4 and the drive motor 7.

With such a configuration, when the slip mechanism 5 detects a slip operation due to the displacement of the upper and lower heads 1 and 2, the shutter mechanism 4 receives a control signal from the sequence circuit 8 which receives the signal. The shutter is closed and the drive motor 7 is stopped.

[0019]

[Effect of the device]

 Since the present invention is configured as described above, the leakage dose equivalent does not increase even if the upper and lower heads are displaced at that location, and the leakage dose equivalent does not increase, so the safety of the device can be maintained. There is an effect like this.

[Brief description of drawings]

FIG. 1 is a diagram showing a specific embodiment of the present invention.

[Explanation of symbols]

 1 Upper head 2 Lower head 3 Synchro belt 4 Shutter mechanism 5 Slip mechanism 6 Switch mechanism 7 Drive motor

Claims (1)

[Scope of utility model registration request] 1. An apparatus for measuring the thickness of an upper head and a lower head, which are arranged facing each other with a measured object interposed therebetween, in a lateral direction on the measured object to measure the thickness of the upper and lower heads (1, 2), respectively. Synchro belt (3) that has stopped and shutter mechanism (4) that is provided on the head that emits radiation and blocks radiation emission
And an overload detection means (5) for detecting that the upper and lower heads are overloaded by a set value or more, a drive motor (7) for driving the synchro belt, and a signal from the overload detection means. A thickness gauge safety device comprising a sequence circuit (8) for controlling the shutter mechanism and the drive motor based on the above.