JP2013250118A - Radiation measuring apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent insertion or the like of an operator's hand when a lid is rotated in a radiation measuring apparatus constituted of a body and the lid.SOLUTION: A lid 16 is installed so as to be rotated around a body 14. A pivot mechanism 36 is formed between the body 14 and the lid 16. A handle 34 is attached on the opposite side of the pivot mechanism 36. In opening motion and closing motion of the lid 16 and in unlocking of a lock state, a knob 38 is required to be pulled upward. By operating the handle 34 while operating the knob 38 (namely by demanding operation by both hands), insertion of a hand or the like can be prevented.

Description

  The present invention relates to a radiation measurement apparatus, and more particularly to a radiation measurement apparatus that measures the radioactivity of a measurement object.

  A radioactivity measurement apparatus is a kind of radiation measurement apparatus, and is used as a food monitor, a soil monitor, a seawater monitor, or the like. The radioactivity measurement apparatus is an apparatus that measures radiation (for example, γ rays) from a measurement object (sample) and calculates radioactivity for the sample.

  In a radiation measurement apparatus such as a radioactivity measurement apparatus, it is necessary to measure radiation from a sample in a state where external radiation (radiation from radioactive materials in the air, cosmic rays, etc.) is shielded or reduced. For this reason, the circumference | surroundings of the measurement chamber which accommodates a sample are wrapped by the shielding member. For example, when the measurement unit is composed of a main body having a measurement chamber and a lid covering the upper opening, a shielding member such as lead is provided inside the main body so as to wrap the measurement chamber. A shielding member is also provided inside. In order to reduce background noise and increase radioactivity measurement accuracy, it is necessary to employ a heavy shielding structure.

  Patent Document 1 discloses an apparatus for measuring the radioactivity of a radiopharmaceutical in a vial. Radiation from the radiopharmaceutical in the vial is detected in a state where the vial is housed inside the shielding container.

JP 2008-224442 A

  In the case where the radiation measuring apparatus is composed of a main body and a lid, and the lid is opened and closed with respect to the main body (particularly, a horizontal turning movement), it is desired to prevent a hand or the like from being caught between the main body and the lid. In particular, if the lid can be opened and closed (especially closed) with only one hand, the other hand will be free, so that hand may be inadvertently in the measurement chamber or accidentally placed on the top of the main unit. It can be considered. For the safety of the operator, it is desirable to limit the operation of the lid in such a state.

  An object of the present invention is to provide a radiation measuring apparatus with high safety. Alternatively, an object of the present invention is to avoid the pinching of hands when the lid is opened and closed on the main body. Alternatively, an object of the present invention is to improve the operability of the opening / closing lid. Alternatively, the measurement accuracy is improved by improving the shielding property of external radiation.

(1) A radiation measurement apparatus according to the present invention includes a main body having a measurement chamber that houses a sample to be measured, a lid that covers the main body, and a mechanism that moves the lid relative to the main body. An opening / closing mechanism having a first operating element and a second operating element operated by both hands.

  According to the above configuration, the lid is provided so as to be openable and closable with respect to the main body, and the lid is provided with the first operating element and the second operating element. And the second operator is operated with both hands. Therefore, it is possible to avoid problems such as a non-operating hand being pinched between the main body and the lid, and it is possible to improve safety. Although it is possible to require a two-handed operation throughout the opening and closing movements of the lid, it is configured to force the two-handed operation at least in a state where safety is a problem (part of the opening and closing movements). It is desirable to do. Conversely, in such a state, it is desirable to restrict the lid from moving even if the lid is operated with one hand. For example, when the opening edge of the main body is held with one hand, even if the lid is closed with the other hand, the lid does not move beyond the limit position where the safety of one hand can be secured. It is desirable to configure. Alternatively, it is desirable that both hands are required when starting the movement of the lid from the closed state and the open state. Desirably, a 1st operation element and a 2nd operation element are set in the position which mutually separated. You may make it provide two operation elements in the rotation axis position in the upper surface of a lid | cover, and the position on the opposite side. In that case, if a vertical operation to the first operation element is requested and a horizontal operation to the second operation element is requested, the independence of the two operations can be ensured and malfunctions can be prevented. Even if any member accidentally collides with the lid that is in an open state and a closing motion force is generated, the movement of the lid is limited according to the above configuration, so that safety can be improved even in such a case.

  In the above configuration, the sample is food, soil, seawater, or the like, and is a solid, liquid, or gas that can be accommodated in the measurement chamber. In order to prevent contamination of the measurement chamber surface, it is desirable to enclose the sample in a sealed container and then place it in the measurement chamber. Generally, a shielding member for shielding extraneous radiation entering the measurement chamber is provided inside the main body and the lid. However, it is also possible to arrange the radiation measuring device itself inside a room constituted by a shielding member. When a shielding member such as lead is arranged inside the lid, a large inertial force is generated during the movement of the lid, so that the necessity of adopting the above configuration is increased from the viewpoint of safety. The first operating element and the second operating element are preferably members that can be gripped by hands, but they can also be configured by operation buttons, levers, and the like. It is desirable to apply the above configuration when the lid slides in the horizontal direction, but the above configuration can also be applied when performing other opening / closing motions. A calculation device (control device) may be provided separately from the radiation measurement device, or the radiation measurement device may include a calculation device. When calculating the radioactivity per unit weight of the sample from the detection signal, the weight of the sample is input separately. Measurement values other than radioactivity (eg, count value, dose, dose rate) may be calculated.

  Preferably, the main body includes a detector that detects radiation from the sample, and a main body side shielding member that surrounds the measurement chamber and the detector, and the lid is a lid side that covers an upper side of the measurement chamber. Including a shielding member, the opening / closing mechanism is a mechanism for rotating the lid in a horizontal direction with respect to the main body. According to this configuration, the shielding member is provided on both the main body and the lid. In order to shield extraneous radiation, the shielding member is made of heavy metal such as lead, and the thickness thereof is, for example, several centimeters. It is desirable that a safety mechanism be provided so that at least the hand or other object is prevented from being caught so that the lid does not move unintentionally. At least one of the first operating element and the second operating element is for releasing such a safety mechanism, and if the operation of the lid with both hands is forced, the safety of both hands can be ensured. Also, in such a configuration, the radiation measurement device is naturally located in front of the user, so that the visual confirmation state of the radiation measurement device can be built naturally, and it is also confirmed that there is no pinching of anything other than the hand. The lid can be closed.

  Preferably, the opening / closing mechanism includes a safety mechanism for restricting the closing movement of the lid, the first operator is a member for releasing the restriction by the safety mechanism, and the second operator is for the lid. A member for exerting an exercising force, and the lid can be closed by simultaneous operation of the first operating element and the second operating element. According to this configuration, the restriction by the safety mechanism is released by the operation of the first operation element, and the lid can be closed by the operation of the second operation element while maintaining the restriction release state. It is desirable to install the two operators sufficiently apart so that the two operators cannot be operated simultaneously with one hand, and it is desirable to configure the operation direction and operation type of the two operators to be different.

  Preferably, the opening / closing mechanism includes a closed state locking mechanism that locks a closed state of the lid, and the first operating element is a member for releasing the lock by the closed state locking mechanism, and the first operating element and The opening movement of the lid can be started after releasing the lock in the closed state by simultaneous operation of the second operation element. According to this configuration, the lock by the closed state lock mechanism is released by the operation of the first operation element, and the opening movement of the lid can be started by the operation of the second operation element while maintaining the state.

  Preferably, the open / close mechanism includes an open state lock mechanism that locks the open state of the lid, and the first operator is a member for releasing the lock by the open state lock mechanism, and the first operator and The closing movement of the lid can be started after unlocking the open state by simultaneous operation of the second operator. According to this configuration, the lock by the open state lock mechanism is released by the operation of the first operation element, and the closing movement of the lid can be started by the operation of the second operation element while maintaining the state.

  The safety mechanism, the closed state locking mechanism, and the open state locking mechanism described above may be substantially realized by a single mechanism. For example, as in an embodiment described later, closed state lock, return restriction (closed movement restriction), and open state lock may be realized by engagement of two cam members. According to such a configuration, the device configuration can be simplified as compared with the case where each mechanism is configured as an independent one.

  Preferably, the first operating element is a member protruding upward from the upper surface of the lid and is provided at a pivot axis position of the lid, and the second operating element protrudes upward from the upper surface of the lid. And is provided at a position opposite to the pivot axis position with the center of the lid therebetween. Although it is possible to obtain the pushing operation of the first operating element, in that case, it is preferable that the operation of raising the first operating element is obtained because malfunction is likely to occur due to contact of other members. Of course, more complicated operations may be requested. Preferably, the first operating element and the second operating element have different forms. According to this structure, since both can be distinguished only by visually recognizing each operation element, operability can be improved. One of clockwise rotation and counterclockwise rotation may be adopted. However, in order to deal with the dominant arm and to avoid interference with surrounding structures, it is allowed to rotate in both directions from the closed state angle. Is desirable.

(2) A radiation measurement apparatus according to the present invention includes a measurement chamber that houses a sample to be measured, a detector that detects radiation from the sample, and a body-side shielding member that surrounds the measurement chamber and the detector. , A cover that covers the main body and has a lid-side shielding member, and a mechanism that pivots the cover in a horizontal direction with respect to the main body, and is operated by both hands of the user. An opening / closing mechanism having a first operating element and a second operating element, wherein the opening / closing mechanism is a first cam member connected to one of the main body and the lid, and a member assembled with the first cam member A second cam member coupled to the other of the main body and the lid, and the movement of the lid is restricted by the engagement of the first cam member and the second cam member, One operating element is the first to release the engagement. A member operating force is applied, the second operating element is a member in which the second operating force to pivot the lid is provided.

  Preferably, the opening / closing mechanism includes an elastic member that generates a biasing force for engagement between the first cam member and the second cam member, and the first cam member is moved to the second position by the first operating force. Move away from the cam member. Preferably, the direction in which the first operating force reaches and the direction in which the second operating force reaches are in an orthogonal relationship. Preferably, the first cam member has a first step-like slope, the second cam member has a second step-like slope, and the first step-like slope and the second step-like slope. Is closed, and the closing movement of the lid is restricted, and the restriction of the closing movement of the lid is released by separating the first step-like slope and the second step-like slope. In the case where two simple slopes are joined, if a horizontal collision force in the opposite direction is generated between the two, a slip occurs between the two and a movement force that separates the slopes upward or downward is generated. On the other hand, according to the joining of two stepped slopes, even if a horizontal collision force in the opposite direction occurs between them, the vertical planes are in contact with each other. Does not occur. Of course, you may make it utilize a simple slope in a part. For example, the opening motion may be configured so that it can be operated with one hand over the entire range or a partial range where safety is not a problem. According to this configuration, it is possible to avoid danger by realizing an opening motion with one hand in an emergency.

  Preferably, the first cam member has a first step-like slope facing in a clockwise direction and a first step-like slope facing in a counterclockwise direction, and the second cam member is A first step-like slope facing in a counterclockwise direction; and a second step-like slope facing in a clockwise direction, the first step-like slope facing in the clockwise direction, and the counterclockwise direction In a state where the second step-like slope facing in the turning direction is joined, the closing movement of the lid in the clockwise direction is restricted, and the first step-like slope facing in the counterclockwise direction and the clockwise direction are restricted. The lid is controlled to close in the counterclockwise direction with the second stepped slopes facing each other, and the first cam member and the second cam member are separated to release the clock of the lid. The restriction of the closing movement in the rotating direction and the counterclockwise direction is released. According to this configuration, the above-described effects can be obtained regardless of whether the lid is turned clockwise or counterclockwise.

  According to the present invention, a highly safe radiation measuring apparatus can be provided. Or, when the lid is opened and closed on the main body, it is possible to avoid pinching the hand. Or the operativity of an opening-and-closing lid can be improved. Alternatively, the measurement sensitivity can be increased by improving the shielding property of external radiation.

It is a block diagram which shows the whole structure of the radiation measurement system which concerns on this invention. It is a perspective view of the measuring apparatus (radiation measuring apparatus) shown in FIG. It is a perspective view which shows the state which opened the lid | cover in the measuring apparatus. It is a disassembled perspective view of a measuring device. It is sectional drawing of a measuring apparatus. It is a figure which shows the opening operation of the cover clockwise with both hands. It is a figure which shows the opening operation of the counterclockwise direction by both hands. It is a figure which shows a turning axis mechanism. It is the figure which opened both the two cam members which a turning axis mechanism has separated, and the cam surface was visible. It is a figure which shows the state which the lid | cover closed and locked. It is a figure which shows the state which the lid | cover closed and the lock release state. It is a figure which shows the state which the lid | cover opened and is locked. It is a figure which shows the effect | action of two cam members in the opening operation | movement of a lid | cover. It is a figure which shows the effect | action of two cam members in the closing operation of a lid | cover. It is a figure for demonstrating the operation content required by closing operation | movement and opening operation | movement.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the drawings.

  FIG. 1 shows the overall configuration of a radiation measurement system according to the present invention. This radiation measurement system is a system that detects radiation from a sample as a measurement target and measures the radioactivity of the sample. The sample is, for example, food, soil, seawater or the like. In particular, the system according to the present embodiment can realize high-sensitivity radioactivity measurement with a low background.

  In FIG. 1, the radiation measurement system is roughly composed of a measurement device (radiation measurement device) 10 and a calculation device (control device) 12. The measuring device 10 detects radiation from the sample, and the arithmetic device 12 is configured as a personal computer or a dedicated information processing device.

  In the present embodiment, the measuring device 10 includes a main body 14 and a lid 16 that covers an upper portion thereof. Inside the main body 14 is provided a measurement chamber 18 for containing a sample. The measurement chamber 18 is a hollow portion, and a plastic scintillator 20 is provided around it. The plastic scintillator 20 is provided adjacent to the side peripheral surface and the lower surface in the measurement chamber 18, and converts the radiation emitted from the sample into light. A photomultiplier tube (PMT) 22 is provided below the plastic scintillator 20 in close contact therewith. The photomultiplier tube 22 converts light into an electrical signal.

  In the present embodiment, a scintillator is used as a radiation detector, but other detectors such as a semiconductor detector can also be used. In the present embodiment, one photomultiplier tube is used. However, a coincidence process or the like may be applied using two or more photomultiplier tubes.

  In measuring the radioactivity of a sample, it is required to effectively shield or reduce radiation from radioactive substances present in the air, radiation from structures and ground, and external radiation such as cosmic rays. In particular, when measuring radioactivity with high sensitivity in a low background state, it is necessary to sufficiently shield such radiation. In the present embodiment, a shielding member is provided in the main body 14 so as to wrap around the measurement chamber 18, the plastic scintillator 20 and the photomultiplier tube 22 around the entire side and the lower side. Further, a shielding member having a size enough to completely cover the entire upper side of the measurement chamber 18 is provided in the lid 16. As a result, the entire periphery of the sample or the like is surrounded by a shielding member having a constant thickness, and high-sensitivity measurement in a low background state can be realized. The shielding member is, for example, lead.

  The arithmetic device 12 has a signal processing unit 24. The signal processing unit 24 includes known circuits such as a wave height discriminator, a waveform shaper, and a counter. The computing unit 26 is configured by a microcomputer or the like, and the radioactivity is computed by the computing unit 26 based on the count value obtained by the signal processing unit 24. The input unit 28 includes a keyboard or the like, and a sample weight is input by the user using the input unit 28. The calculation unit 26 calculates the radioactivity per unit weight based on such information. The display unit 30 displays the calculation result. Instead of radioactivity, dose, dose rate, etc. may be calculated. Further, the count value itself may be displayed on the display unit 30. Incidentally, a background measurement value may be obtained in a state where a sample is not accommodated in the measurement chamber 18, and the background measurement value may be subtracted from the sample measurement value. Although not shown in FIG. 1, it is also possible to configure the calculation unit 26 to communicate with other devices. Further, the calculation unit 26 may compare the measured value with the reference value to determine the presence or absence of radioactive contamination.

  FIG. 2 is a perspective view of the measuring apparatus 10 shown in FIG. As described above, the measuring device 10 is constituted by the main body 14 and the lid 16, and FIG. 2 shows a state in which the lid 16 is closed in the measuring device 10. The main body 14 includes an upper part 14A and a lower part 14B. That is, the main body 14 has a split type configuration. The main body 14 has a cylindrical or bullet-like shape as a whole, and its horizontal cross-sectional size increases from above to below. At the lower end of the upper portion 14A, a shoulder portion forming a slope is formed. For example, five leg portions 32 are provided on the lower surface side of the lower portion 14B. A plurality of casters or the like may be provided there.

  The lid 16 has a disk shape, and its upper surface is rounded into a convex spherical shape. A pivot axis mechanism 36 is provided across the lid 16 and the main body 14. The pivot mechanism 36 has a knob 38 that can be grasped by one hand of the user. The knob 38 is a member that moves up and down as will be described later. A handle 34 is provided at a position on the opposite side of the pivot shaft mechanism 36 through the center point of the lid 16. The handle 34 is gripped by the other hand of the user, and by holding the handle 34 and applying a horizontal force to the handle 34, the lid 16 is rotated in the clockwise direction around the rotation axis of the pivot shaft mechanism 36. It is possible to swivel counterclockwise. Incidentally, the position of the lid 16 shown in FIG. 2 is set to 0 degree, and in this embodiment, the lid can be rotated by, for example, 110 degrees or 135 degrees at the maximum in both the clockwise direction and the counterclockwise direction. In any case, as described later, it is desirable that the lid 16 can be swiveled until the entire upper opening of the measurement chamber is exposed.

  In this embodiment, the turning shaft mechanism 36 has various functions such as a closed state lock mechanism, an open state lock mechanism, and a return motion restriction mechanism. This will be described in detail later. The measuring apparatus 10 of the present embodiment is required to be operated with both hands when operating the lid 16, thereby improving safety.

  Incidentally, the weight of the measuring device 10 is, for example, 70 to 80 kg, and the height thereof is, for example, 50 cm. The maximum outer diameter is 34 cm, for example. The measuring device 10 is preferably installed on the floor surface, but may be installed on a table, for example. In the present embodiment, the measuring apparatus 10 is configured to be divided into a plurality of parts, and in particular, the main body 14 has a split-type configuration. It is possible to easily carry out the transfer operation.

  FIG. 3 shows a state where the lid 16 is open. In this state, the upper opening of the measurement chamber is completely exposed. Reference numeral 18A represents an opening edge of the measurement chamber. Reference numeral 40 represents an inner lid provided in the upper part of the measurement chamber. It is provided as needed.

  As described above, the lid 16 is provided with the pivot shaft mechanism 36, and the lid 16 pivots in the clockwise direction and the counterclockwise direction with the rotation axis of the lid 16 as the center of gravity. The state shown in FIG. 3 is a state where the maximum turning angle is reached, that is, the open state, and the state is locked. Reference numeral 42 represents a recess for receiving the lower end of the plunger provided on the lid 16 side. That is, the handle shown in FIG. 2 is attached to the upper end portion of the shaft body, and the shaft body constitutes a plunger. When the lower end fits into the recess 42, a constant click feeling or a latched state is obtained, and an angle of 0 degrees can be recognized in such a state. In this state, the lock mechanism operates. In the present embodiment, the lid 16 can be moved in both the clockwise direction and the counterclockwise direction, but it is of course possible to allow the lid 16 to rotate only in one direction. In any case, in this embodiment, the lid 16 can be swung by an operation with both hands, as will be described in detail later.

  FIG. 4 shows an exploded perspective view of the measuring apparatus. The lid 16 has a case, and a shielding member 44 that shields external γ rays is provided therein. The shielding member 44 is a disk-shaped member having a thickness of several centimeters, for example. A part thereof is a notch 44A, and its form is, for example, a semicircular shape. A pivot axis mechanism 36 is disposed there.

  The case 46 provided in the main body 14 has a double structure, that is, an inner case and an outer case, and a plastic scintillator is accommodated between them. The inside of the case 46 is hollow, that is, in a well shape, and that portion is the measurement chamber 18. The photomultiplier tube 22 is disposed below the case 46. One or a plurality of substrates are arranged around the periphery. For example, it constitutes a preamplifier or the like.

  In the main body 14, the upper portion 14 </ b> A has a case, and a shielding member 50 is provided in the case. The shielding member 50 is a cylindrical member having a thickness of several centimeters, for example. The lower part 14B of the main body 14 has a case, and a shielding member 52 is provided therein. The shielding member 52 is also a cylindrical member having a certain thickness. In FIG. 4, the disk-shaped shielding member provided below the shielding member 52 is not shown. Each of the above cases is made of aluminum or resin.

  FIG. 5 shows a cross-sectional view of the measuring apparatus. This sectional view is an explanatory view, and details are not shown. A measurement chamber 18 is provided inside the main body 14, and a plastic scintillator 20 is provided around the measurement chamber 18. The entire plastic scintillator 20 is surrounded by a case, and the case includes an inner case 46B and an outer case 46A. The case functions as a light shielding member and prevents the entry of extraneous light into the scintillator. However, the bottom surface of the scintillator is exposed for light output and is directed to the light receiving surface of the photomultiplier tube 22. More specifically, a thin light guide (light guide member) is provided between the light receiving surface and the scintillator.

  A cylindrical shielding member 50 is provided in the upper portion 14A so as to enclose the measurement chamber 18, the plastic scintillator 20, and the like, and a cylindrical shielding member 52 is provided in the lower portion 14B so as to enclose the periphery of the photomultiplier tube 22. Is provided. A disk-shaped shielding member 54 is provided below the photomultiplier tube 22.

  On the other hand, the lid 16 is provided with the disk-shaped shielding member 44 having a notch in a part thereof as described above. Reference numeral 56 denotes a ring-shaped shielding member that covers the opening edge of the measurement chamber 18. That is, the shielding member 56 having such a configuration is provided so that extraneous radiation does not enter from the gap between the main body 14 and the lid 16.

  As shown in FIG. 5, a shielding member 44 that is a heavy object is provided in the lid 16, and a large inertia force can be generated when the lid 16 is turned. Therefore, it is necessary to consider the improvement of safety on the premise of such inertial force.

  FIG. 6 shows an operation example in which the lid 16 is turned in the clockwise direction. As shown in the figure, when the knob is gripped by the right hand R, the handle is gripped by the left hand L, and when the operating force is exerted in the clockwise direction as indicated by reference numeral 58 by the left hand L while the knob is lifted slightly upward by the right hand R, The lid 16 opens. That is, it is possible to turn the lid 16 using both hands while releasing the locked state. In this case, operation with only one hand is not allowed.

  Similarly to the above, FIG. 7 shows an operation of moving the lid 16 counterclockwise to open the lid 16. As shown in the drawing, the handle is gripped by the right hand R, and the knob is gripped by the left hand L. The cover 16 can be opened by turning the handle in the counterclockwise direction with the right hand R as shown by reference numeral 60 while lifting the knob slightly upward to release the locked state. Even in this case, an operation with both hands is required.

  6 and 7 show the opening operation, but the operation with both hands is required even in the closing operation. At the time of the closing operation, a hand or the like is likely to be caught, and in such a case, it is highly necessary to perform an operation with both hands.

  FIG. 8 shows the turning shaft mechanism 36. A pivot shaft mechanism 36 is provided on the opposite side of the handle 34 through the center on the horizontal plane in the lid 16. Incidentally, the handle 34 has a grip 34A and a shaft body 34B. The grip 34A is a ball-shaped member connected to the upper end portion of the shaft body 34B, and the lower end of the shaft body 34B functions as a plunger.

  In this embodiment, the pivot shaft mechanism 36 has a knob 38, and the knob 38 is connected to the lifting cam member 64 through an intermediate body. On the other hand, the knob 38 and the lift cam member 64 together constitute a lift body 66, which is attached to the main body. That is, even if the lid 16 performs a turning motion, the elevating body 66 does not rotate. However, the lifting body 66 is provided so as to be movable up and down with respect to the main body, and the lifting body 66 can be shifted upward by grasping the knob 38 and pulling it up. Although not shown in FIG. 8, the pivot shaft mechanism 36 has an elastic member that is a spring, and the elastic member always applies a downward biasing force to the elevating body 66. Therefore, when the knob 38 is lifted, the lifting body 66 is pulled up so as to overcome such a biasing force.

  The elevating body 66 has a rotation axis along its center line, and two pins 70 are provided on it. The rotating shaft fixed to the main body itself does not move up and down, and the height of the two pins 70 is not changed. On the other hand, the elevating cam member 64 has two slits (pin grooves), and two pins are inserted into the two slits. The rotating shaft provided in the center of the raising / lowering body 66 does not move up and down, that is, the height of the two pins 70 is fixed. On the other hand, the two slits move up and down together with the lifting body 66. Therefore, the vertical movement width of the lifting body 66 is defined by the engagement of the two pins and the two slits.

  The rotating cam member 68 is fixed to the lid 16. Due to the meshing relationship between the elevating cam member 64 and the rotating cam member 68, closed state lock, return regulation, open state lock, and the like are realized as described in detail below.

  FIG. 9 shows the elevating cam member 64 and the rotating cam member 68. FIG. 9 shows a state in which the two cam members 64 and 68 are opened in the vertical direction so that the cam surfaces can be seen.

  First, the elevating cam member 64 will be described. The member is attached to the main body as described above, and only the lifting movement is allowed. The raising / lowering cam member 64 has a disk-shaped base 72, and the lower surface side is a cam surface. The lock groove 74A is a rectangular groove, which functions when realizing a closed lock. A lock groove 74B is also formed on the opposite side of the lock groove 74A. It also implements a closed lock. In the circumferential direction on the cam surface, a triangular block 76A is provided on one side of the lock groove 74A, and a triangular block 76B is provided on the other side of the lock groove 74A. The triangular blocks 74A and 74B have downward stepped slopes, and the slopes are opposite to each other. More specifically, the portion close to the lock groove 74A protrudes downward most, and the amount of downward protrusion decreases as it moves away from it, and a staircase structure is provided on such a slope. .

  Similarly to the above, triangular blocks 76C and 76D are provided on one side and the other side of the lock groove 74, respectively. A gap 78A is formed between the triangular blocks 76B and 76C, and a gap 78B is formed between the triangular blocks 76A and 76D. A vertical through-hole is formed in the central portion of the lift cam member 64.

  Next, the rotating cam member 68 will be described. The rotating cam member 68 is integrated with the lid. The upper surface of the base 80 forms a cam surface, and a chevron block 82A is provided there. The central portion of the mountain block 82A in the circumferential direction is a top portion, and slopes are formed on the left and right sides thereof, and each slope has a staircase structure. A chevron block 82B having a similar configuration is also provided on the opposite side of the chevron block 82A. In the closed state of the lid, the chevron block 82A fits into the lock groove 74A as shown in FIG. 9, and the chevron block 82B fits into the lock groove 74B. As a result, the closed state lock is realized.

  A convex portion 84A is formed on one side of the chevron block 82A via a gap 86A. Similarly, a convex portion 84B is provided on the other side of the chevron block 82B via a gap 86B. These convex portions 84A and 84B function as stoppers and are members protruding upward from the cam surface. A gap 88A is provided between the chevron block 82B and the convex portion 84A, and a gap 88B is provided between the chevron block 82B and the convex portion 84B.

  FIG. 9 shows an engagement relationship in a state in which the lid is closed. When the door is opened, the rotating cam member 68 rotates with the lid on the lifting cam member 64. In that case, the lift cam member 64 is pulled upward with respect to the rotary cam member 68 to release the lock. Locking is executed in the closed state, and locking is also performed in the open state (maximum open state). In each locked state, the locked state can be released by raising the elevating cam member 64 by a predetermined amount. Further, as will be described later, a step-like slope having a predetermined direction is formed between the two cam members, and two step-like slopes having the same inclination angle are fitted to each other in the two cam members. With such a configuration, the return turning motion of the lid is restricted. That is, unless the state in which the elevating cam member 64 is pulled upward is maintained, the two stepped slopes meet each other so that the lid does not move. Thereby, it is possible to prevent pinching of the hand and improve safety.

  FIG. 10 shows a closed state of the lid. In this case, the elevating body 66 is lowered to the lowest end by the action of gravity and an elastic body, and the rotating cam member 68 and the elevating cam member 64 are engaged with each other. The locked state is formed. Specifically, the chevron block 82A formed on the rotary cam member 68 enters the corresponding lock groove, and the same state occurs in the other chevron blocks. prohibited. That is, it is in a closed lock state.

  FIG. 11 shows the unlocked state. That is, as shown in the figure, the lifting / lowering body 66 is slid upward as the knob 38 is lifted, and the lock groove 74A is lifted upward with respect to the mountain block 82A, and the other side is in the same state. The locked state is released. That is, in this state, the lower cam member can be rotated with respect to the upper cam member, which means that the lid can be turned. Incidentally, as described above, the upward movement range of the elevating body 66 is defined by the contact relationship between the two slits and the two pins 70. As shown in FIG. 11, one hand is required to lift the knob 38 upward, and since the knob 38 is on the rotation axis, it is not possible to apply a turning force to the lid with the other hand. By applying an acting force to the handle at a position away from the rotation axis by hand, the lid can be turned. That is, it is possible to start the turning motion of the lid only by the operation with both hands.

  FIG. 12 shows the open state of the lid. That is, the lid rotates counterclockwise, reaches the swivel end, and an open lock state occurs. The convex portion 84A and the chevron block 82A formed on the rotating cam member 68 enter a gap or a stepped slope, and a similar meshing occurs on the side opposite to the side shown in the figure, whereby the action of the two cam members is achieved. This restricts the movement of the lid in the closing direction. In order to release such a locked state, it is necessary to pull up the knob upward so that the chevron blocks 82A and the like can be separated from the gap or do not collide with the slope.

  Next, the operation of the two cam members 64 and 68 will be described with reference to FIGS. 13 and 14. In FIGS. 13 and 14, two cam members 64 and 68 are shown as development views. These are explanatory drawings, and the form of the cam member is schematically depicted. In any case, the form of each cam member in this embodiment is an example, and various forms can be adopted as long as the same function can be realized.

  FIG. 13A shows a closed lock state. That is, the lid is closed and it is locked. Here, the configuration of the respective cam members 64 and 68 will be described again. In the raising / lowering cam member 64, the code | symbol 100 is equivalent to the range of 360 degree | times, and the part beyond it is shown with the broken line for convenience of explanation. On the cam surface of the elevating cam member 64, a triangle block 76D, a gap 78B, a triangle block 76A, a lock groove 74A, a triangle block 76B, a gap 78A, a triangle block 76C, and a lock groove 74B are provided from left to right in FIG. It has been. Here, the triangular blocks 76D and 76B have stepped slopes inclined in one direction, and the triangular blocks 76A and 76C have stepped slopes inclined in the other direction.

  On the other hand, in the rotating cam member 68, reference numeral 102 represents a range of 360 degrees, and the angle blocks 82A and 82B are provided at a pitch of 180 degrees. Of the two chevron blocks 82A and 82B, convex portions 84A and 84B are formed on one side and the other side of one chevron block 82A in the vicinity of the chevron block 82A.

  In the state shown in (A), the two chevron blocks 82A and 82B are fitted in the two lock grooves 74A and 74B, that is, the open lock state is established. In this state, the two cam members 64 and 68 cannot be rotated relative to each other.

  As shown in (B), when the elevating cam member 64 is pulled upward, the two angle blocks 82A and 82B are detached from the two lock grooves 74A and 74B, and the restriction in the rotational direction is released.

  For example, in the example shown in FIG. 13, when the rotating cam member 68 moves in the left direction on the paper surface and the apexes of the mountain blocks 82A and 82B exceed the apexes of the triangular blocks 76A and 76C, the state as shown in FIG. It becomes. That is, in (C), the two mountain blocks 82A and 82B are in contact with the two stepped slopes corresponding to the descending slope, and in such a state, even if the lifting cam member 64 is released, the force that restricts the turning does not work exceptionally. . Of course, the lifting cam member 64 may be kept pulled up by the user and the lid may be turned. However, in this state, the lifting cam member 64 can be temporarily released. If the turning of the lid is continued as it is, the state shown in (D) is obtained.

  In (D), in this example, the chevron blocks 82A and 82B are in contact with the triangular blocks 76D and 76B, and the convex portion 84B is in contact with the slope of the triangular block 76A beyond the apex. No further turning of the lid is allowed due to the limitations of other mechanisms, and the maximum open turning state is established at that time, and the movement of the convex portion 84B is held down by the triangular block 76A. The return movement of the cam member 68 is restricted. That is, the open lock state is established. At this time, the convex portion 84A exceeds the triangular block 76D. It may also be configured to produce a stopper action.

  By the way, when the state shown in (C) is shifted to the state shown in (D), an operation of raising the elevating cam member 64 slightly upward may be requested, or such upward raising is performed specially. The state shown in (D) may be established naturally using the contact relation of the slope without any change. In any case, it is desirable that the lid is reliably locked in the open state and the lid does not return and move inadvertently.

  Next, the operation during the lid closing motion will be described with reference to FIG. (E) shows a state in which the lift cam member 64 is lifted slightly upward and then the lid is started to rotate again. The convex portion 84B functioning as a stopper passes over the triangular block 76A. . As shown in (E), when the stepped slope on the forward side of the two chevron blocks 82A, 82B hits the stepped slope of the two triangular blocks 76A, 76C, a relationship similar to the contact between the vertical surfaces occurs, The movement of the rotating cam member 68, that is, the closing movement of the lid is restricted. For example, when the closed state is set to 0 degree, such a state is established when approaching to a position of 75 degrees with respect to the closed state, that is, the operation with both hands is forced again in such an angle range. Thus, even when one hand is inserted into the measurement chamber, it is possible to effectively prevent the hand from being pinched between the main body and the lid.

  That is, as shown in (F), when the lid is to be closed and moved, the knob is operated with a hand different from the hand holding the handle to raise the elevating cam member 64 upward, so that the two angle blocks It is necessary to bring the vertices of 82A and 82B to a position exceeding the vertices of the two triangular blocks 76A and 76C. The state is shown in (G). That is, during the closing movement, an operation with both hands is required in an angle range where the hand is likely to be caught. When the lid is operated with both hands, the line of sight naturally observes the upper surface of the lid, so that there is an advantage that other foreign objects can be prevented from being caught.

  Finally, as shown in (H), the two chevron blocks 82A and 82B are fitted into the two lock grooves 74A and 74B, and the state is locked. In that case, the knob is opened.

  In FIG. 15, the above operation contents are arranged from the viewpoint of operation. (A) shows an opening operation, and (B) shows a closing operation. The numbers described in each cell represent the front-rear relationship under the same angle condition, and indicate that the state shifts in order from the smallest number to the largest number.

  As indicated by reference numeral 104, when the lid is at the origin position in the opening operation, the lifting knob is first lifted with one hand, thereby releasing the lock. Then, the lid is operated in the opening direction by operating the grip with the other hand while maintaining the pulled-up state. As indicated by reference numeral 106, during the turning, the lifting knob can be released in the present embodiment, and even in this case, the turning motion, that is, the opening motion is not particularly restricted. However, the return movement of the lid is restricted. As a result, the operation of returning the lid from the middle is prevented, so that problems such as inadvertent pinching are prevented. As shown by reference numeral 108, when the maximum turning angle is reached, the opening state can be locked by first releasing the lifting knob after the lid is forcibly stopped by a predetermined mechanism. . Incidentally, in the transition from the state indicated by reference numeral 106 to the state indicated by reference numeral 108, the lifting knob may be raised, or a closed lock is formed naturally without performing such an operation. You may be made to do. This is as described above.

  On the other hand, in the closing operation, as shown by reference numeral 110, the lifting knob is pulled upward by one hand, thereby releasing the lock, and the grip, that is, the handle is operated by the other hand, so that the lid is closed. Operating force is given. Then, during the turning shown by reference numeral 112, it is necessary to always lift the lifting knob, that is, an operation with both hands is compelling to prevent the hand or the like from being caught. If the lifting knob is released, the closing motion itself is restricted. As indicated by reference numeral 114, when the origin position is reached, the lid is first positioned at 0 ° by the operation of the grip, that is, the handle, and then the lift knob is released to be in the closed lock state.

  As described above, in the present embodiment, when the lid is opened and closed, particularly in the closing operation of the lid, the operation with both hands is necessary when reaching the angle range where the pinching is a problem. The problem that the other hand is pinched while performing the operation with the hand can be surely prevented, and since the operation with both hands is required, the user naturally faces the device. From this, there is an advantage that the lid can be opened and closed after the device is sufficiently visually confirmed.

  In the above-described embodiment, the locked state and the return regulation are realized by the contact relationship between the two cam members. Of course, such a state may be formed using another mechanism. It is also possible to open and close the lid using a drive source. Even in this case, it is possible to effectively prevent pinching as described above by obtaining the operation of the switches and buttons with both hands.

  In the above embodiment, the operation of the knob upward and the operation of the handle in the horizontal direction are used, that is, the two operation forces are set to have an orthogonal relationship. It is effectively prevented to realize the above simultaneously. Further, since the knob is lifted upward and is not configured to push down the knob, it is possible to prevent a problem that an object is unnecessarily placed and presses the knob. In the above embodiment, the shape of the handle and the knob are completely different. Specifically, the handle has a ball-like grip, and the knob is configured as a flat knob-like member. The risk of misidentifying each of the two controls can also be reduced. In particular, since the grip has a ball shape, there is an advantage that the grip feeling can be maintained regardless of the angle.

  DESCRIPTION OF SYMBOLS 10 Measurement apparatus (radiation measurement apparatus), 12 Arithmetic apparatus (control apparatus), 14 Main body, 16 Lid, 18 Measurement chamber, 20 Plastic scintillator, 22 Photomultiplier tube, 34 Handle, 36 Rotating shaft mechanism, 64 Elevating cam member, 68 Rotating cam member.

Claims (12)

A main body having a measurement chamber for accommodating a sample to be measured;
A lid covering the body;
An opening / closing mechanism having a first operating element and a second operating element, which is a mechanism for moving the lid with respect to the main body and is operated by both hands of a user;
A radiation measuring apparatus comprising: The apparatus of claim 1.
The main body includes a detector that detects radiation from the sample, and a main body-side shielding member that surrounds the measurement chamber and the detector,
The lid includes a lid side shielding member that covers an upper side of the measurement chamber,
The opening / closing mechanism is a mechanism for rotating the lid in a horizontal direction with respect to the main body,
A radiation measuring apparatus characterized by that. The apparatus of claim 2.
The opening / closing mechanism includes a safety mechanism that regulates the closing movement of the lid,
The first operating element is a member for releasing the restriction by the safety mechanism,
The second operating element is a member for exerting a moving force on the lid,
The lid can be closed by simultaneous operation of the first operator and the second operator.
A radiation measuring apparatus characterized by that. The device according to any one of claims 1 to 3,
The opening / closing mechanism includes a closed state locking mechanism that locks the closed state of the lid,
The first operator is a member for releasing the lock by the closed state lock mechanism,
The opening movement of the lid can be started after unlocking the closed state by simultaneous operation of the first operating element and the second operating element.
A radiation measuring apparatus characterized by that. The apparatus according to any one of claims 1 to 4,
The open / close mechanism includes an open state lock mechanism that locks the open state of the lid,
The first operator is a member for releasing the lock by the open state lock mechanism,
The closing movement of the lid can be started after unlocking the open state by simultaneous operation of the first operating element and the second operating element.
A radiation measuring apparatus characterized by that. The device according to any one of claims 1 to 5,
The first operating element is a member protruding upward from the upper surface of the lid, and is provided at a pivot axis position of the lid,
The second operating element is a member protruding upward from the upper surface of the lid, and is provided at a position opposite to the pivot axis position with the center of the lid in between.
A radiation measuring apparatus characterized by that. The device according to any one of claims 1 to 6,
The first operator and the second operator have different forms;
A radiation measuring apparatus characterized by that. A main body having a measurement chamber containing a sample to be measured, a detector for detecting radiation from the sample, and a main body side shielding member surrounding the measurement chamber and the detector;
A lid that covers the main body and has a lid-side shielding member;
An opening / closing mechanism having a first operating element and a second operating element that are operated by both hands of a user, wherein the lid pivots in a horizontal direction with respect to the main body;
Including
The opening and closing mechanism is
A first cam member coupled to one of the main body and the lid;
A second cam member coupled to the first cam member, the second cam member coupled to the other of the main body and the lid;
Including
The closing movement of the lid is restricted by the engagement of the first cam member and the second cam member,
The first operating element is a member to which a first operating force for releasing the engagement is applied,
The second operating element is a member to which a second operating force for turning the lid is applied.
A radiation measuring apparatus characterized by that. The apparatus of claim 8.
The opening / closing mechanism includes an elastic member that generates a biasing force for engagement between the first cam member and the second cam member,
The first cam member is separated from the second cam member by the first operating force;
A radiation measuring apparatus characterized by that. The apparatus of claim 9.
The direction that the first operating force reaches and the direction that the second operating force reaches are orthogonal to each other.
A radiation measuring apparatus characterized by that. The apparatus of claim 8.
The first cam member has a first stepped slope;
The second cam member has a second stepped slope;
The closing movement of the lid is restricted in a state where the first step-like slope and the second step-like slope are joined,
The restriction on the closing movement of the lid is released by separating the first step-like slope and the second step-like slope.
A radiation measuring apparatus characterized by that. The apparatus of claim 8.
The first cam member has a first step-like slope facing in the clockwise direction, and a first step-like slope facing in the counterclockwise direction,
The second cam member has a second step-like slope facing in the counterclockwise direction, and a second step-like slope facing in the clockwise direction,
The closing movement of the lid in the clockwise direction is restricted in a state where the first step-like slope facing in the clockwise direction and the second step-like slope facing in the counterclockwise direction are joined,
The closing movement of the lid in the counterclockwise direction is restricted in a state where the first step-like slope facing in the counterclockwise direction and the second step-like slope facing in the clockwise direction are joined together,
The restriction of the closing movement of the lid in the clockwise direction and the counterclockwise direction is released by separating the first cam member and the second cam member.
A radiation measuring apparatus characterized by that.