JP3934584B2 - Body surface monitor - Google Patents

Description

  The present invention relates to a body surface monitor that measures radiation from a measurement subject.

  The body surface monitor functions as a body surface radiation measurement device, and is installed in, for example, a nuclear power plant or a nuclear fuel processing facility. That is, a body surface monitor is installed at the entrance and exit of the radiation management area, and radiation is measured for the exposure management of workers entering the radiation management area and workers leaving the radiation management area.

  A conventional body surface monitor is generally composed of a main body, an entrance door, an exit door, and the like. Conventionally, when the entrance door is open and the exit door is closed, the worker enters the measurement chamber, the worker turns 90 degrees in the measurement chamber, and the right hand and the left hand are formed on the front. Insert your hand into the measuring unit. In this state, the entrance door is closed, and radiation is measured over a predetermined time. After completion of the measurement, the exit door is opened and the worker leaves the measurement chamber. Then, the exit door is closed and the entrance door is opened. This process is repeated for each worker. Patent Document 1 listed below discloses a body surface monitor that can perform measurement without changing the orientation in a measurement chamber.

  In the body surface monitor, in order to detect radiation from the measurement subject with high sensitivity, there is a demand to place the radiation detector as close to the measurement subject as possible. Therefore, a body surface monitor that is provided with a head detector that moves up and down and can adjust the height of the head detector according to the height of the subject has also been put into practical use (for example, Patent Document 2 and Patent Document 3). ). In addition, there is Japanese Patent Application No. 2002-15961 as an unpublished patent application related to the present application.

Japanese Patent No. 2807168 Japanese Utility Model Publication No. 63-129848 JP-A-4-310892

  For the person to be measured, when the head detector with a heavy feeling descends from above in a state of being confined in the measurement chamber, in some cases, a considerable psychological pressure is felt. In addition, the approach from above does not necessarily increase the radiation detection sensitivity for the left and right sides of the head.

  On the other hand, for a body surface monitor having a movable detector as exemplified above, it is desirable that safety be improved even if the detector moves. In the prior art, an electric drive source such as a motor has been used to drive the movable detector. However, the mechanism is inevitably complicated, and an electric drive source is required to obtain a sufficient and smooth driving force. Can be pointed out.

  An object of the present invention is to provide a body surface monitor having good performance and high practical value.

  Another object of the present invention is to reduce the feeling of psychological pressure given to the person to be measured in the body surface monitor or to improve the detection sensitivity.

  Another object of the present invention is to increase safety in a body surface monitor.

  Another object of the present invention is to provide a good drive system in a body surface monitor.

(1) The present invention provides a main body having a measurement chamber for accommodating a person to be measured, an openable / closable entrance door provided at an entrance opening of the measurement chamber, and an openable / closable provided at an exit opening of the measurement chamber. A plurality of radiation detectors for detecting radiation from a subject housed in the measurement chamber, the radiation detector group having at least one tilting radiation detector, and the tilting radiation detection And at least one tilting mechanism for changing the tilting angle of the device, and a control unit for controlling the tilting mechanism and setting the tilting angle of the tilting radiation detector based on the height of the measurement subject. It is characterized by.

  According to the above configuration, the sensitive surface of the tilting radiation detector can be controlled by accurately controlling the tilt angle of the tilting radiation detector according to the height of the person being measured. Can be close. In this state, highly sensitive radiation measurement can be performed. In addition, according to the above configuration, the psychological pressure can be reduced or eliminated because the radiation detector is tilted obliquely. In order to deal with subjects of various heights, it is desirable to provide a plurality of tilt type radiation detectors in the vertical direction. Further, detection sensitivity can be further improved by providing a pair of opposed tilting radiation detectors and causing them to fall together. When the height is below a certain height, it is desirable that only one tilting type radiation detector is tilted and operated. The control unit performs tilt control according to the height of the person being measured. The height is preferably detected by a sensor, but may be read from a card carried by the person being measured.

  Preferably, the tilt mechanism includes an air drive mechanism that varies an tilt angle of the tilting radiation detector using an air cylinder. When an electric drive source is used, the mechanism may be complicated or the size of the mechanism may need to be increased. However, if the air drive method is used, the required power can be obtained with a relatively compact mechanism. The drive mechanism is relatively simple. There is also a psychological sense of security because of the smooth exercise.

  Preferably, the tilting mechanism includes an auxiliary biasing mechanism that gives an auxiliary biasing force in a rising direction to the tilting radiation detector, and an air driving force by the air driving mechanism and an auxiliary biasing force by the auxiliary biasing mechanism. As a result, the tilted radiation detector rises and moves.

  According to the above configuration, even when the air drive source is small, or even when the acting direction of the rising force and the rising direction of the tilted radiation detector are close to orthogonal, the auxiliary biasing force is working. So you can get enough uplifting power. The tilting-type radiation detector may be moved down by utilizing its own weight, or an air driving force may be applied.

  Preferably, the main body is provided with a plurality of tilting radiation detectors facing the measurement chamber. According to this configuration, the detection sensitivity can be improved by bringing one or more tilting radiation detectors close to each other according to the height and body shape of the measurement subject.

  Preferably, the plurality of tilted radiation detectors include two tilted radiation detectors that are opposed to each other. Preferably, the two tilting radiation detectors facing each other are selectively tilted according to a predetermined order when the measurement subject is lower than a certain height. According to the selective operation (for example, alternate operation), the mechanical burden can be distributed or evenly distributed.

  Desirably, the fixed height is a height at which physical interference between the two tilting radiation detectors facing each other can be avoided when the two tilting radiation detectors fall down. According to this configuration, it is possible to improve detection sensitivity while reliably avoiding physical contact between the two tilting radiation detectors.

  Preferably, the plurality of tilted radiation detectors include two tilted radiation detectors that are vertically related to each other. They may be selectively operated according to the height, or the respective inclination angles may be appropriately set according to the body shape.

  Desirably, a sandwiching detector is provided in the tilting radiation detector. According to this configuration, when the tilting radiation detector moves back, it is possible to detect a situation where a hand or the like has been pinched and take necessary measures.

  Preferably, the pinch detector is a belt-like sensor provided entirely or partially along the peripheral edge of the back surface of the tilting radiation detector. If a pinch detector is provided over a wide range, the safety can be further improved.

  Preferably, the tilting radiation detector has a contact detector that detects that an object has contacted the surface. For example, it is assumed that a tilted radiation detector that is in a fallen state or in a fallen motion state touches the head when the person to be measured stands on a toe or performs an action such as a jump. In such a case, the situation can be detected and necessary countermeasures can be taken.

(2) Desirably, a body surface monitor is provided at a main body having a measurement chamber for accommodating a person to be measured, an openable / closable entrance door provided at an entrance opening of the measurement chamber, and an exit opening of the measurement chamber. and openable outlet door has, a plurality of radiation detectors that detect the radiation from the subject accommodated in the measuring chamber, a radiation detector unit having at least one movable type radiation detector, using pressurized air to which the surface monitor is introduced from the installed facilities, including the at least one air-driven mechanism for moving the movable type radiation detector.

  According to the above configuration, air can be introduced from the facility where the body surface monitor is installed, and the movable radiation detector can be moved using the air, thereby simplifying the configuration of the body surface monitor. This is also advantageous in terms of power saving. As described above, all the conventional body surface monitors have been operated by an electric drive source. However, it is desirable to replace the air monitor with air drive or to use it together with air drive. The movable radiation detector is preferably one that tilts, but may also be one that moves up and down.

(3) Desirably, a body surface monitor is provided at a main body having a measurement chamber for accommodating a measurement subject, an openable / closable entrance door provided at an entrance opening of the measurement chamber, and an exit opening of the measurement chamber. and openable outlet door has, a plurality of radiation detectors that detect the radiation from the subject accommodated in the measuring chamber, a radiation detector unit having at least one movable type radiation detector, A pinch detector provided on the back side of the movable radiation detector for detecting pinching of an object, and when the pinching of the object is detected, the retracting operation of the movable radiation detector is stopped or reversed. including a control unit, the to. According to this configuration, safety can be improved.

(4) It is desirable to adopt a vertically long rhombus shape, a vertically long elliptical shape, or the like as the overall shape of the measurement chamber. According to this configuration, since at least one of the upper part and the lower part of the measurement chamber has a form narrowed inward, the radiation detector can be brought closer to the body surface. Therefore, sensitivity can be improved. The form of the measurement chamber is determined so as to cover various heights and various body shapes. The entrance door and the exit door may be a single door or a two door. In the latter case, it is desirable to adopt the double door method. It is also possible to employ a configuration in which one or both of the entrance door and the exit door are omitted.

  As described above, according to the present invention, a body surface monitor having good performance and high practical value can be provided. The inclined radiation detector can reduce the psychological pressure given to the measurement subject or improve the detection sensitivity. Moreover, safety can be further enhanced by various sensors. Further, if the air driving method is adopted, various advantages described above can be obtained.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the drawings.
FIG. 1 shows a preferred embodiment of a body surface monitor according to the present invention, and FIG. 1 is a perspective view of the body surface monitor viewed from the entrance side.

  The body surface monitor shown in FIG. 1 is installed at, for example, a nuclear power plant. Specifically, the body surface monitor is provided at the entrance and exit of a radiation control area, and body surface contamination is measured for workers entering and leaving the radiation control area. It is a device to do. The facility where the body surface monitor is installed is provided with a pressurized air outlet (not shown) at a required location, from which the pressurized air is introduced into the body surface monitor and an air cylinder or the like. Is driven.

  The body surface monitor is roughly divided into a main body 10, an entrance door 12, an exit door 14, a base 16 and a ceiling portion 17. The main body 10 has a measurement chamber 18 as a cavity formed from the inlet opening to the outlet opening. In FIG. 1, the Y direction is the direction in which the worker advances, the X direction is the left-right direction with respect to the worker, and the Z direction is the height direction.

  The measurement chamber 18 as a cavity is roughly divided into three parts. That is, it is divided into an upper part, a middle part and a lower part. As shown in FIG. 1 and FIG. 3 to be described later, the middle part is wide in the X direction, the upper part is gradually narrowed in the X direction toward the upper part, and the lower part is narrowed in the X direction toward the lower part. The width of is gradually narrowing. Therefore, the measurement chamber 18 has a substantially vertically long rhombus shape as viewed from the entrance side. This rhombus shape is a shape corresponding to various heights and body shapes of an approximately assumed worker, and is a form in which a radiation detector described later can be brought close to the body surface as much as possible.

  In the measurement chamber 18, a pair of hand detection units 26 are provided at the left and right ends in the X direction in the intermediate portion. The hand detection unit 26 has a groove 28 as a vertical groove or a V-shaped groove communicating with the measurement chamber 18. This groove 28 is a groove penetrating in the Y direction. The right hand or the left hand is inserted into the groove 28, and in this state, the radiation of the inner and outer surfaces of the hand is measured. A partition wall 30 is formed between the groove 28 and an intermediate portion of the measurement chamber 18, and radiation detectors S6 and S12 are provided in the partition wall 30 (see FIG. 3). Radiation detectors S8 and S14 are provided on the inner surface of the groove 28 facing the radiation detectors S6 and S12 (see FIG. 3). These radiation detectors and other radiation detectors are planar radiation detectors, and specifically include a scintillator plate and a plurality of photomultiplier tubes. The radiation detector group includes a plurality of tilting radiation detectors and a plurality of double-sided radiation detectors.

  The main body 10 is formed with two upper inner surfaces 22 and two lower inner surfaces 24 as inclined surfaces facing the measurement chamber 18. The upper inner surface 22 is inclined toward the measurement chamber 18 at a constant angle, and the lower inner surface 24 is also inclined upward while opening upward.

  Therefore, as described above, the measurement chamber 18 has a vertically long rhombus shape as a whole. The measurement chamber 18 further has a ceiling surface and a floor surface, and a radiation detector S9 for measuring radioactive contamination of the foot is provided on the floor surface. At the time of measurement, the operator stands up on the floor surface, and the radiation is measured with both hands inserted into the respective hand detection units 26.

  Further explaining the radiation detector, the entrance door 12 is provided with three radiation detectors S1 to S3 from the upper side to the lower side in the present embodiment. Further, two radiation detectors S4, S10 and S5, S11 are provided on the two upper inner surfaces 22 side by side (see FIG. 3). In addition, two radiation detectors S6, S12 and S7, S13 are provided on the two lower inner surfaces 24 side by side (see FIG. 3). The exit door 14 is provided with three radiation detectors from the top to the bottom in the present embodiment, but is not shown.

  Of course, the arrangement of each radiation detector is merely an example, and various arrangement methods can be used. However, it is desirable to arrange each radiation detector so that body surface contamination can be measured over the entire body of the operator who is the subject.

  In the above, the radiation detectors S4, S5, S10, and S11 are tilting radiation detectors, and the radiation detectors S6 and S12 are double-sided detectors. Their configuration will be described in detail later.

  The ceiling portion 17 is provided with a display 17A for displaying the measurement status, and the liquid crystal display 51 for displaying an instruction to the next person to be measured is provided on the entrance side. In addition, although the same liquid crystal display is provided in the exit side, it is utilized when using an exit side as an entrance side for convenience.

  The entrance door 12 is attached to the shaft 12A and is rotatable, and similarly, the exit door 14 is attached to the shaft 14A and is rotatable. They are driven by pressurized air introduced as described above. The plurality of tilting radiation detectors are also driven by pressurized air. However, it may be replaced by an electric drive system or may be used in combination. A member 12B provided between the shaft 12A and the entrance door 12 is provided with an auxiliary liquid crystal display 12C. Similarly, an auxiliary liquid crystal display (see FIG. 2) is also provided on a member provided between the shaft 14A and the exit door 14. On these liquid crystal displays, guidance and the like are displayed to the subject during measurement.

  A transmissive or reflective optical height sensor 52 is provided on the entrance side of the measurement chamber 18. The height sensor 52 is constituted by a large number of optical elements arranged in the vertical direction, and the height or height classification of the subject is measured. The measurement is preferably performed when the person to be measured enters, but the height may be measured at the stage of being accommodated in the measurement chamber 18. The height sensor 52 shown in FIG. 1 is an example, and other sensors such as an ultrasonic sensor can be used. Based on the height measured by the height sensor 52, a control unit (not shown) controls the tilting motion (falling motion, rising motion) of the plurality of tilting radiation measuring instruments.

  A sensor 54 provided facing each groove 28 is an optical sensor that detects that a hand has been inserted into the groove 28. A sensor 53 provided on the lower inner surface 24 is an optical sensor for detecting the presence of a person to be measured in the measurement chamber. Each sensor 53, 54 is a reflective or transmissive sensor. The controller determines the presence and proper posture of the person to be measured based on the outputs of the sensors 53 and 54, and controls the operation of the body surface monitor based on the judgment. The mat sensor 50 is provided at a waiting place for the next person to be measured, and detects that the next person to be measured is standing there. The detection result is also sent to the control unit. Further, a load sensor may be disposed on the base 16.

  FIG. 2 is a perspective view showing the outlet side of the body surface monitor. Reference numeral 55 denotes a box in which an electronic circuit including a control unit is accommodated. The entrance door 12 and the exit door 14 have a vertically long rectangle, while the measurement chamber has a vertically long rhombus. Even when both doors are closed, a plurality of substantially triangular shapes in which the measurement chamber and the outside communicate with each other. A gap is formed, and the presence of such a gap gives a sense of security to the measurement subject accommodated in the measurement chamber 18.

  As shown in FIGS. 1 and 2, in the above configuration, the shaft 12 </ b> A of the entrance door 12 is set on the right side when viewed from the entry direction, but of course it may be on the left side. Similarly, the shaft 14A of the outlet door 14 is formed on the right side when viewed from the outlet side to the inlet side, but of course it may be on the left side. Alternatively, the entrance door 12 and the exit door 14 may be double doors that open from the center in the left-right direction.

  In FIG. 1, in this embodiment, the height of the vertex of the partition wall 30 is set within a range of 90 to 100 cm, for example, and preferably 95 cm from the floor surface. The distance between the centers of the two grooves 28 is, for example, 60 to 120 cm, and desirably 90 cm. Further, the depth of the groove 28 is, for example, 30 to 45 cm, and preferably 40 cm. Furthermore, although the height from the floor surface to the ceiling surface is 2 m, for example, other values may be adopted. The angle of inclination of the upper inner surface 22 from the vertical is, for example, 0 to 80 °, and preferably 35 °. The open inclination angle of the lower inner surface 24 is, for example, 0 to 20 °, and preferably 10 °. However, each of the numerical values given above is an example, and other values can be adopted. For example, all or part of the lower inner surface 24 may be a vertical surface. Also, the upper inner surface 22 can be entirely or partly vertical, and the inclination angle can be set in two or more steps. Ultimately, the measurement chamber 18 can be configured as a vertically long ellipse. However, according to the embodiment of the present embodiment, since it has a relatively simple form and can perform efficient measurement, it has practical value.

  Next, the operation of the body surface monitor (control contents of the control unit) will be described. First, in a state where the exit door 14 is closed, an operator (a person to be measured) enters the measurement chamber 18 from the entrance opening side and stands on the floor surface. At that time, the height of the worker is measured by the height sensor 52, and the presence of the worker is detected by the sensor 53. In the standing state, the operator faces the inner surface of the exit door 14. In this state, both hands are inserted into the two hand detection units 26. The state is detected by the sensor 54. Prior to the start of measurement, the entrance door 12 is closed. Simultaneously with such a process (or before or after closing the entrance door 12), in order to increase the detection sensitivity of the upper part of the head etc. according to the height of the operator, among the four tilting radiation detectors One or more of these fall down. The tilt angle depends on the height of the worker, and in any case, the tilted radiation detector is at such an angle that the sensitive surface of the radiation detector can be brought close to the worker without touching the worker. The posture is adjusted. Radiation measurement is performed for a predetermined time from the time when the entrance door 12 is closed or the time when the necessary operation is completed.

  When the radiation measurement is completed, only the exit door 14 is opened, which allows the operator to exit forward. Before or simultaneously with the opening operation of the exit door 14, one or more tilting radiation detectors that are in a fallen state return to the original state. However, if the height data of the next worker can be obtained in advance, it may be adjusted to an inclination angle corresponding to the height of the worker in order to shorten the operation time. After the worker exits, the exit door 14 is closed and the entrance door 12 is opened, and the same process is repeated.

  Therefore, the operator as the person to be measured does not need to change the direction inside the measurement chamber 18, so that the measurement time per person can be shortened. Moreover, since the radiation detector is brought close to the body surface particularly in the upper and lower parts of the operator, the detection sensitivity can be increased. Further, the measurement chamber 18 shown in FIG. 1 has a rhombus shape, and the measurement chamber 18 is configured to have a certain height, so that radiation measurement is performed by accommodating almost all workers. It is possible.

  In the body surface monitor of the present embodiment, hand part detection units 26 are fixedly provided at both left and right ends of the measurement chamber 18. However, the length of the hand is generally proportional to the height, and no particular problem arises even with such a fixed arrangement. Moreover, in general, in the case of a tall person, two hands can be inserted into the hand detection unit 26 without opening the two upper arms so much, while in the case of a short person Since the two upper arms are opened to some extent and the two hands are inserted into the hand detection unit 26, the difference in arm length and the height difference are caused by such differences in the upper arm opening or the bending angle of the joint. Can be absorbed or adjusted. For this reason, even if the hand part detection unit 26 is fixedly arranged, radiation measurement on both hands can be performed reliably according to various heights. However, the hand part detection unit 26 may be movable in the vertical direction as necessary.

  FIG. 3 schematically shows the arrangement of radiation detectors in the body surface monitor. On the right side from the entrance side, radiation detectors S4, S5, S6, S8, and S7 are provided from the top to the bottom. On the left side from the entrance side, radiation detectors S10 and S11 are provided from the top to the bottom. , S12, S14, and S13. A radiation detector S9 is provided on the floor surface.

  The radiation detectors S6 and S12 are double-sided radiation detectors provided on the partition wall 30, which measure both radiation from the torso or waist of the subject and radiation from the inside of the arm. To do. As will be described later with reference to FIG. 4, each of the radiation detectors S6 and S12 includes a scintillator plate on one surface and the other surface, and the emitted light is detected by one or more photomultiplier tubes. To do. If two independent radiation detectors are provided in the partition wall 30, the thickness of the partition wall 30 becomes unnecessarily thick or difficult to arrange, but according to the present embodiment, By using such a double-sided detection type radiation detector, highly sensitive radiation detection can be performed while making the partition wall thin.

  In the configuration example shown in FIG. 3, the radiation detectors S4, S5, S10, and S11 are tilting radiation detectors. Reference numerals S4 ', S5', S10 ', and S11' each indicate a state of being collapsed with the lower end side as the rotation center. Either the upper radiation detectors S4 and S10 or the lower radiation detectors S5 and S11 are tilted according to the height of the measurement subject. However, such a tilting operation does not have to be performed when the height of the person being measured is quite high. Further, the upper radiation detectors S4 and S10 may be tilted and the lower radiation detectors S5 and S10 may be tilted. That is, it is desirable to adjust the inclination angle of each radiation detector so that each radiation detector comes close to the head and shoulders of the subject according to the height of the subject.

  Further, as indicated by reference numeral S4 ″, if only one of the opposed radiation detectors S4 and S10 is greatly tilted and moved, the person with a short height is the same as the ceiling type radiation detector. Measurement on the upper side can be performed. Even in this case, if the pair of radiation detectors S5 and S11 in the lower stage are also tilted, they can be brought closer to the body surface to improve detection sensitivity.

  The large falling movement as described above is performed when the height of the person to be measured is equal to or less than a certain height. As the certain height, the pair of radiation detectors S4 and S10 physically interfere (collision) when they fall. It is set as the height corresponding to the angle immediately before the end. In the case where only one such tilting motion is performed, the pair of radiation detectors S4 and S10 may be selectively performed (preferably alternately) in a predetermined order. If it does in that way, the load added to each mechanism part can be equalized.

  As described above, since a plurality of posture variable radiation detectors are provided on the left and right and top and bottom, high sensitivity measurement can be performed by bringing each radiation detector close to the body surface according to the height or body shape of the subject. .

  FIG. 4 shows a configuration example of the double-side radiation detector as a cross-sectional view. The inside of the case 120 is hollow, and substrates 124A and 124B made of transparent acrylic or the like are provided on one surface and the other surface thereof. The scintillator plates 126A and 126B made of plastic scintillators and the like are superposed on them, and they are further covered with aluminized mylar films 128A and 128B. The case 120 is provided with a pair of photomultiplier tubes 130 (only one photomultiplier tube is shown in the figure). Due to the incidence of radiation, light is emitted from the scintillator plates 126A and 126B, and the light passes through the substrates 124A and 124B and is emitted into the case 120. When the light reaches the light receiving surface of the photomultiplier tube 130, it is detected as an electrical signal. The output signals of the pair of photomultiplier tubes are input to a known coincidence circuit or the like.

  FIG. 5 shows tilting radiation detectors arranged in two upper and lower stages. These correspond to the radiation detectors S10 and S11 shown in FIG. 3, but the radiation detectors S4 and S5 basically have the same configuration.

  The tilt mechanism 60 is roughly constituted by an air drive mechanism 64 and an elastic biasing 66. The air drive mechanism 64 includes an air cylinder 68 and a piston arm 70, and the piston arm 70 can be advanced and retracted by air pressure. The base end side of the air cylinder 68 is supported by a shaft 74, and the working end of the piston arm 70 is supported by a shaft 72. Therefore, when the piston arm 70 is retracted into the air cylinder 68, the radiation detector S10 can be raised and moved back.

  However, as shown in FIG. 5, when the radiation detector S10 is tilted to a substantially horizontal state, the rotation axis 76 of the radiation detector S10 and the above-described two axes 72 and 74 are combined. Therefore, the direction of the rising force by the piston arm 70 is orthogonal or nearly orthogonal to the rising direction of the radiation detector S10. As a result, depending on only the air drive mechanism 64, a sufficient rising force is applied. I can't.

  Therefore, in the present embodiment, the elastic urging mechanism 66 is provided. This elastic biasing mechanism is configured as a winding spring with both ends pulled out, and is roughly configured by a linear portion 66B, a coil portion 66C, and a linear portion 66D. One end 66 </ b> A of the elastic biasing mechanism 60 is connected to a predetermined position in the air drive mechanism 64, and the other end 66 </ b> E of the elastic biasing mechanism 66 is engaged with a predetermined position in the frame 59. With such a configuration, the elastic biasing mechanism 66 always applies a weak rising force to the radiation detector S10 using a return force by a spring, and even when the radiation detector S10 has a certain weight, it is air driven. Coupled with the action of the mechanism 64, the radiation detector S10 can be raised and moved upward smoothly and reliably.

  Incidentally, when the radiation detector S10 falls down and moves, its own weight may be used. The frame 59 constitutes the outer wall of the measurement chamber 18 shown in FIG.

  Of course, for example, by setting the position of the shaft 74 above the frame 59, it is possible to generate a sufficient rising force only by the air drive mechanism 64, but in general, it is sufficient for the side portion of the body surface monitor. There is no vacant space, and in addition to this, when the radiation detector S10 is fully restored, it is necessary to fold and store the air drive mechanism 64 in such a narrow space. There is. As a result, the positional relationship between the axes as shown in FIG. 5 is inevitably generated. In this embodiment, even in such a case, a sufficient rising force is generated by the elastic urging mechanism 66 as described above. Can be generated.

  In the lower radiation detector S11 shown in FIG. 5, only the air drive mechanism 62 is provided as the tilt mechanism. That is, the shaft 94 on the proximal end side of the air driving mechanism 62 is set to be considerably above the rotating shaft 98 set at the lower stage of the radiation detector S11. From the positional relationship of the shafts 98, 94, 96, the air driving mechanism 62 is set. It is possible to exert a sufficient rising force. The point that the air driving drive 62 is constituted by the air cylinder 90 and the piston arm 92 is the same as that of the upper radiation measuring instrument S10.

  In the radiation measuring instrument S10, a cover 82 is provided on the front side of the case 80, and the cover 82 is biased forward by a spring force with respect to the case 80. That is, the cover 82 is movable in the front-rear direction within a certain range with respect to the case 80. In such a configuration, when the cover 82 contacts any object, usually the head of the subject, for example, the contact is detected by the contact sensor 84. When such a detection is made, the control unit stops the falling motion of the radiation detector S10 or reversely operates it to get the radiation detector 10 up and move. This increases safety.

  A belt-like pinching detection sensor 89 is provided along the edge of the upper surface, that is, the back surface of the case 80. That is, there may be a problem that the operator's hand is caught between the back side of the case 80 and the frame 59 during the rising motion of the radiation detector S10. A detection sensor 86 is provided to detect the situation. When such a detection is made, the return movement upward of the radiation detector S10 is stopped by the control of the control unit, or a fall-down movement is performed as a reverse movement. . As a result, safety is further improved.

  As for the radiation detector S <b> 11, the cover 104 is provided to be movable back and forth with respect to the case 102, and the cover 104 is biased forward with respect to the case 102 by a spring force. If the head or the like comes into contact with the cover 104, this is detected by the sensor 106. Further, a belt-like pinching detection sensor 108 is provided partially along the edge of the back surface of the case 102, and safety is enhanced by these sensors 106 and 108.

  Incidentally, reference numerals 78 and 100 in FIG. 5 denote units that house scintillators, photomultiplier tubes, and the like.

  FIG. 6 shows a state in which the radiation detector S10 and the radiation detector S11 are raised and completely folded up. For example, when measuring radiation for a worker who is quite tall, the radiation is measured in the state shown in FIG.

It is the perspective view which looked at the body surface monitor concerning the present invention from the entrance side. It is the perspective view which looked at the body surface monitor which concerns on this invention from the exit side. It is explanatory drawing for demonstrating arrangement | positioning of a some radiation detector. It is sectional drawing which shows the structural example of a double-sided radiation detector. It is a figure for demonstrating the specific structural example of a tilting mechanism. It is a figure which shows the state by which the radiation detector of the upper and lower two steps was folded up.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Main body, 12 Entrance door, 14 Exit door, 16 Base, 17 Ceiling part, 26 Hand part detection unit, S4, S5, S10, S11 Tilt-type radiation detector.

Claims (12)

A main body having a measurement chamber for accommodating a person to be measured;
An openable / closable entrance door provided at the entrance opening of the measurement chamber;
An openable / closable exit door provided at the exit opening of the measurement chamber;
A plurality of radiation detectors for detecting radiation from a measurement person accommodated in the measurement chamber, the radiation detector group having at least one tilting radiation detector;
At least one tilting mechanism for changing the tilting angle of the tilting radiation detector;
A control unit configured to control the tilt mechanism based on the height of the measurement subject and set the tilt angle of the tilting radiation detector;
Only including,
The body surface monitor characterized in that the tilt mechanism includes an air drive mechanism that varies the tilt angle of the tilting radiation detector using an air cylinder . The body surface monitor according to claim 1,
The body surface monitor characterized in that the air drive mechanism moves the tilting radiation detector using pressurized air introduced from a facility where the body surface monitor is installed . The body surface monitor according to claim 1 ,
The tilting mechanism includes an auxiliary biasing mechanism that gives an auxiliary biasing force in the rising direction to the tilting radiation detector,
The body surface monitor, wherein the tilting radiation detector rises and moves by an air driving force by the air driving mechanism and an auxiliary biasing force by the auxiliary biasing mechanism. The body surface monitor according to claim 1,
The body surface monitor, wherein the main body is provided with a plurality of tilting radiation detectors facing the measurement chamber. The body surface monitor according to claim 4,
The body surface monitor, wherein the plurality of tilted radiation detectors include two tilting radiation detectors facing each other. The body surface monitor according to claim 5,
The body surface monitor characterized in that the two tilting radiation detectors facing each other are selectively tilted according to a predetermined order when the measurement subject is lower than a certain height. The body surface monitor according to claim 6, wherein
The body surface monitor according to claim 1, wherein the certain height is a height capable of avoiding physical interference between the two tilting radiation detectors facing each other when the two tilting radiation detectors fall down. The body surface monitor according to claim 4,
The body surface monitor, wherein the plurality of tilted radiation detectors include two tilted radiation detectors that are vertically related to each other. The body surface monitor according to claim 1,
A body surface monitor, wherein the tilting radiation detector is provided with a pinching detector for detecting pinching of an object . The body surface monitor according to claim 9,
The body surface monitor, wherein the pinch detector is a belt-like sensor provided entirely or partially along a peripheral edge of the back surface of the tilting radiation detector. The body surface monitor according to claim 1,
The tilting radiation detector has a contact detector that detects that an object has contacted the surface of the body. The body surface monitor according to claim 9,
A body surface monitor comprising: a pinching control unit that stops or reverses the retracting operation of the tilting radiation detector when pinching of the object is detected .

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