JP2014137256A - Personal dosimeter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a personal dosimeter that alleviates shock power affecting a substrate and reduces the number of components.SOLUTION: A holding mechanism 76 comprises a rubber leg 66. The rubber leg 66 includes: a head 66A exhibiting a vibration-proof function or the like at a first face 58A side of a substrate 58; a neck 66B fitted into an open hole 58C of the substrate 58; and a body 66C exhibiting a vibration-proof function or the like at a second face 58B side of the substrate 58. A protrusion 82 is inserted into the head 66A. Also, a protrusion 86 is inserted into the body 66C. The protrusion 82 is inserted up to the considerably deep inside of the head 66A, so that the displacement of the substrate 58 is laterally and vertically restricted to avoid collision with other member. The rubber leg 66 can be disposed by only insertion of the head 66A into the open hole 58C.

Description

  The present invention relates to a personal dosimeter, and more particularly to a portable personal dosimeter used for exposure management.

  The personal dosimeter is a measuring instrument used for exposure management of workers engaged in work in a facility that handles radioactive materials or radiation, or for exposure management of ordinary people. A personal dosimeter usually has a radiation sensor, an electronic circuit and a battery. The radiation sensor measures radiation (for example, gamma rays). In the electronic circuit, the dose, dose equivalent, accumulated dose, accumulated dose equivalent, and the like are calculated based on the output signal from the radiation sensor, and the calculation result is displayed on the display. Personal dosimeters are typically placed inside or outside the chest pocket of an operator or the like. A personal dosimeter may be attached to the belt. A personal dosimeter may be hung from the neck using a string.

  A clip member or an attachment member is used for mounting the personal dosimeter. Such a member sandwiches a cloth or a belt. In a typical personal dosimeter in the past, the clip mechanism has a clip piece that opens and closes (seesaw motion), and a metal spring that exerts an elastic force on the clip piece. For example, a cloth is inserted between the end of the clip piece and the surface of the personal dosimeter, and the cloth is pressed toward the main body surface by the end of the clip piece. When the personal dosimeter is worn, the head of the personal dosimeter is usually exposed from the upper side of the pocket. A radiation sensor is arranged in such a head. Patent Documents 1 and 2 show examples of conventional personal dosimeters.

JP 2002-131435 A JP-A-8-313634

  In general, a substrate on which an electronic circuit, a radiation sensor, and the like are mounted is disposed inside the personal dosimeter. Those electronic components are vulnerable to shock and vibration. In particular, when an impact is applied to the radiation sensor, erroneous counting is likely to occur. Therefore, it is necessary to effectively protect those electronic components, and in particular, effective mitigation of impacts coming from various directions is required. For this reason, when a complex vibration-proof structure is added to the substrate, the number of parts increases, the structure becomes complicated, and there is a problem of cost increase, and the assembly workability is lowered.

  An object of the present invention is to effectively reduce an impact with a simple configuration in a personal dosimeter. Alternatively, an object of the present invention is to be able to effectively mitigate impacts from various directions on a substrate. Alternatively, an object of the present invention is to reduce the number of parts of a personal dosimeter, to reduce costs, and to improve assembly workability.

  A personal dosimeter according to the present invention includes a main body case composed of a first case and a second case arranged in the front-rear direction, a substrate provided in the main body case and mounted with a radiation sensor, and the first case; A plurality of holding structures that elastically hold the substrate between the second case, at least one of the plurality of holding structures being provided inside the first case, A first holding part having a contact surface and a first protrusion, a second holding part provided inside the second case and having a second contact surface and a second protrusion, and a through hole of the substrate A portion that is inserted and protrudes toward the first surface of the substrate and has a first opening into which the first protrusion is inserted, between the first surface of the substrate and the first contact surface. A head functioning as a spacer, and a portion connected to the head, the through hole As a spacer between the second surface of the substrate and the second contact surface, it has a neck located inside and a second opening that is connected to the neck and into which the second protrusion is inserted. And an elastic member having a functioning body.

  According to the above configuration, the elastic member having the head, the neck, and the body is used for holding and fixing the substrate. The head is a jig and a spacer that are sandwiched between the first surface of the substrate and the first contact surface, and exhibits an impact absorbing function (including a vibration isolating function) on the first surface side of the substrate. The body is a jig and a spacer sandwiched between the second surface of the substrate and the second contact surface, and exerts an impact absorbing action on the second surface side of the substrate. In this way, the elastic member is attached so as to penetrate the substrate, and thereby the elastic action is exhibited on both sides of the substrate, so that the substrate and the electronic components mounted thereon can be effectively protected from impact. It is desirable to provide the elastic member in each of the plurality of holding structures. When the method of fixing the elastic member by inserting the head of the substrate hole is adopted, workability is improved because screwing and fixing of the elastic member can be omitted. Also, the number of parts can be reduced.

  Preferably, the tip of the first protrusion is closer to the substrate than the tip of the second protrusion, and the thickness of the head in the front-rear direction is smaller than the thickness of the body in the front-rear direction. Since the first protrusion is close to the substrate, the lateral displacement and longitudinal displacement of the substrate with respect to the first case can be effectively limited, and the substrate and electronic components mounted thereon are prevented from colliding with members around the substrate. it can. On the premise of such a configuration, a certain amount of lateral displacement and longitudinal displacement is allowed on the second surface side of the substrate, but there is a positional deviation or assembly error between the first case and the second case. Even if it exists, the substrate can be firmly and elastically fixed.

  Preferably, the first holding part has a support column standing up from the inner surface of the first case as a part of the first case, the first protrusion is formed at a tip of the support column, The first abutment surface is formed around the first protrusion at the tip. According to this structure, a part of 1st case can be utilized as a support | pillar, and a 1st protrusion part and a 1st contact surface can be formed by using the support | pillar as a base.

  Desirably, the 2nd projection part which constitutes the 2nd maintenance part has projected from the 2nd case as a part of the 2nd case, and the 2nd contact surface which constitutes the 2nd maintenance part is the above-mentioned It is a part of the inner surface of the second case and around the base of the second protrusion. Although a support may be provided on the second surface side of the substrate, the inner surface of the second case is used as a contact surface as it is for simplification of the structure.

  Preferably, the cross section of the first protrusion has a tapered shape from the first surface of the substrate to the first case side. According to this configuration, it is possible to facilitate insertion of the first projecting portion into the first opening.

  Preferably, the level of the tip surface of the first protrusion is substantially equal to the level of the first surface. According to this configuration, the substrate can be prevented from moving greatly in the substrate surface direction due to the bending deformation of the head.

  Preferably, the second projecting portion has a tapered shape from the inner surface of the second plate to the substrate side, and the second opening portion is tapered from the opening surface to the bottom surface thereof. According to this configuration, the second protrusion can be easily inserted into the second opening.

  According to the present invention, an impact can be effectively reduced with a simple configuration in a personal dosimeter. Or according to this invention, the impact which reaches from a various direction with respect to a board | substrate can be relieve | moderated effectively. Or according to this invention, the number of parts of a personal dosimeter can be reduced, cost can be reduced, and assembly workability | operativity can be improved.

It is a 1st perspective view which shows suitable embodiment of the personal dosimeter based on this invention. It is a 2nd perspective view of the personal dosimeter shown in FIG. It is a rear view of the personal dosimeter shown in FIG. It is a perspective view which shows the main body and attachment mechanism which comprise the personal dosimeter shown in FIG. It is a side view of the personal dosimeter shown in FIG. It is a front view of the personal dosimeter shown in FIG. It is sectional drawing which shows the AA arrow cross section in FIG. It is sectional drawing which shows the BB arrow cross section in FIG. It is a figure which shows the state which removed the front case in the personal dosimeter. It is sectional drawing which shows CC cross section shown in FIG. It is an expanded sectional view of a holding structure. It is a figure which shows a seal structure. It is a figure for demonstrating the effect | action in a seal structure. It is a perspective view which shows packing and a protrusion row | line | column. It is a perspective view which shows packing and a seal groove.

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

(1) Description of Basic Configuration FIG. 1 shows a preferred embodiment of a personal dosimeter according to the present invention, and FIG. 1 is a perspective view thereof. The personal dosimeter 10 is attached to a worker who works in a facility that handles radiation or radioactive materials. Of course, a personal dosimeter may be attached to the general public. The personal dosimeter is used in personal exposure management, and has a function of measuring and displaying a dose, a dose equivalent, an integrated dose, an integrated dose equivalent, and the like. In the present embodiment, the personal dosimeter is attached to the breast pocket as described below. However, it may be attached to other parts.

  In FIG. 1, the personal dosimeter 10 roughly includes a main body 12 and an attachment mechanism 14. The main body 12 has a substantially rectangular parallelepiped shape, and when viewed with the main body 12 as a reference, a right end portion 16 is provided on the right side thereof, and a left end portion 18 is provided on the left side thereof. Each of the end portions 16 and 18 is a portion protruding outward in the horizontal direction in FIG. Moreover, each end part 16 and 18 is extended in the up-down direction in FIG. 1, and has a form like an ellipse seeing from the side surface direction.

  The main body 12 has a main body case as will be described later, and a semiconductor sensor as a radiation sensor is provided in the main body case. The semiconductor sensor is arranged in the upper part in the main body 12, and radiation (gamma rays) detected by the semiconductor sensor is indicated by reference numeral 20. Electronic parts such as a board, a battery, an electronic circuit, and a buzzer are further provided inside the main body case. An upper surface 12A of the main body 12 is slightly inclined forward, and a display 26 is provided on the upper surface 12A. The display 26 is a liquid crystal display, for example. An LED 28 is further provided on the upper surface 12A.

  On the front surface 12B of the main body 12, an opening 24 for a buzzer is formed slightly above the intermediate level. Incidentally, a switch portion 29 is provided on the side surface of the left end portion 18. The switch unit 29 is constituted by two push switches in the present embodiment. That is, in this embodiment, the operation part in the personal dosimeter 10 is provided on the side surface of the main body. As described above, since the upper surface 12A of the main body 12 is inclined, the visibility of the display 26 is enhanced.

  Next, the attachment mechanism 14 will be described. The attachment mechanism 14 is detachably attached to the main body 12. Specifically, the attachment mechanism 14 includes a right attachment member 30, a left attachment member 32, and a clip member 34. The right attachment member 30 is a member that is attached to the right end portion 16, and is specifically configured as a member that surrounds the periphery of the right end portion 16 like an endless track. Similarly, the left attachment member 32 has a form surrounding the left end 18. In the example shown in FIG. 1, the clip member 34 is a member provided to connect the right mounting member 30 and the left mounting member 32. In the illustrated example, a clip member 34 is provided on the front side of the main body 12. In FIG. 1, reference numeral 36 represents a breast pocket, and a fabric 36 </ b> A on the front side is sandwiched between the clip member 34 and the front surface 12 </ b> B of the main body 12. As will be described in detail later, the clip member 34 includes a pressing bar 46 that performs such clamping, and has two arms for applying an elastic force to the pressing bar. As shown in FIG. 1, the pressing bar 46 extends in the left-right direction, that is, in the horizontal direction, and can hold down the fabric 36A with a relatively long distance or with an expanded area.

  FIG. 2 shows a perspective view of the personal dosimeter viewed from another direction. An insertion hole 38 is formed in the upper portion of the right end portion 16 described above. The insertion hole 38 is a slit on which the strap is hooked. A circular opening is formed in the lower portion of the right end portion 16, and a cap 36 is inserted therein. The cap 36 is a member that closes an opening of a storage chamber for storing a battery, that is, a battery. The cap 36 can be attached to the opening by rotating the cap 36 in one direction, and the cap 36 can be removed from the opening by rotating the cap 36 in the other direction. In the present embodiment, the battery is provided on the bottom inside the main body so as to lie down horizontally.

  FIG. 3 shows the back of the personal dosimeter. Reference numeral 40 denotes a light emitting / receiving element for performing communication using infrared rays. The back surface constitutes a substantially flat surface. Incidentally, it is also possible to attach the attachment mechanism so that the above-mentioned pressing bar is provided on the back side of the main body. In such a case, the fabric is sandwiched between the pressing bar and the back surface, and the main body is mounted on the front side of the breast pocket.

  FIG. 4 is a perspective view showing a state where the attachment mechanism 14 is detached from the main body 12. First, the main body 12 will be described again. The main body 12 has the right end portion 16 and the left end portion 18 as described above. These end portions 16 and 18 have a form protruding outward when viewed from the main body 12, and mounting grooves 43 and 45 are formed on the side peripheral surface thereof. The right mounting member 30 and the left mounting member 32 described above are fitted into the mounting grooves 43 and 45. The right end portion 16 has an upper end portion 16A and a lower end portion 16B. Similarly, the left end portion 18 has an upper end portion 18A and a lower end portion 18B.

  Next, the attachment mechanism 14 shown in FIG. As described above, the attachment mechanism 14 includes the right mounting member 30, the left mounting member 32, and the clip member 34. The right attachment member 30 includes a right attachment member main body 47 and a connecting part 48. The right mounting member main body 47 has a hook portion 30A that is hooked from above on the upper end portion 16A of the right end portion 16, and has a hook portion 30B that is hooked from below on the lower end portion 16B of the right end portion 16. Yes. On the front side with respect to the main body 12, the hook portion 30 </ b> A and the hook portion 30 </ b> B are continuous, and that portion constitutes the front portion.

  Similarly, the left mounting member 32 includes a left mounting member main body 49 and a connecting component 50. The left mounting member main body 49 has a hook portion 32A that is hooked from above on the upper end portion 18A of the right end portion 18, and has a hook portion 32B that is hooked from below on the lower end portion 18B of the left end portion 18. . On the front side of the main body 12, the hook portion 32A and the hook portion 32B are connected by the front side portion. These rear end portions are connected by the connecting component 50 described above.

  In the mounting groove 43 described above, the right mounting member 30 having a strip-like and loop-like form is provided. Similarly, the attachment groove 45 is provided with a left attachment member 32 having a strip-like and loop-like form. The attachment mechanism 14 is firmly attached to the main body 12 by fitting the attachment members 30 and 32 into the attachment grooves 43 and 45. Even if a force is applied to the attachment mechanism 14 in the up-down direction, the left-right direction, and the front-rear direction, the attachment mechanism 14 is not easily detached from the main body 12. This is because the mounting members 30 and 32 completely hold the end portions 16 and 18 as described above.

  The clip member 34 is a portion connecting the right attachment member 30 and the left attachment member 32 on the front side. Specifically, the clip member 34 has a right arm 42, a left arm 44, and a pressing bar 46. The right arm 42 and the left arm 44 have an S-shape when viewed from the side. The base portion of the right arm 42 is integrated with the right mounting member 30, and the right arm 42 extends downward from the mounting portion and is integrated with one end of the pressing bar 46. Similarly, the left arm 44 is integrated with the left mounting member 32 and is integrated with the other end of the pressing bar 46.

  The right arm 42 includes a root portion 42A connected to the right mounting member 30, a mountain portion 42B having a mountain shape that rises forward from there, and a valley portion 42C that is provided at the tip and falls to the main body 12 side. And a warped part 42D that warps forward in the forward direction. Similarly, the left arm 44 has a root portion 44A, a mountain portion 44B, a valley portion 44C, and a warped portion 44D. The pressing bar 46 is held by the form of each of the arms 42 and 44, and an elastic biasing force toward the main body 12 is exerted on the pressing bar 46. The pressing bar 46 receives elastic force in parallel at both ends thereof.

  The pressing bar 46 is provided slightly below the intermediate level on the front side of the main body 12 and is configured as a member extending in the horizontal direction. The pressing bar 46 constitutes a slightly wider handle up and down, and it is possible to put a fingertip from the lower side of the pressing bar and lift it slightly upward, and when the fabric is inserted from below, The fabric is received by a wedge-shaped gap on the back side of the bar 46. A slit is formed on the back side of each arm 42, 44, and cloth is inserted into the slit. Incidentally, the clip member 34 is made of, for example, resin.

  The right mounting member main body 47 and the connecting component 48 are connected by two knobs 52A and 52B in the example shown in FIG. Similarly, the left mounting member main body 49 and the connecting component 50 are connected by two knobs 54A and 54B. Incidentally, as a connection method, in addition to such a fitting method, an adhesive method can be adopted together with or instead of the fitting method, or screwing or the like may be used.

  FIG. 5 shows a side view of the personal dosimeter. As shown in the figure, the upper surface 12A of the main body 12 is inclined by an angle θ with respect to the horizontal plane. Thereby, the visibility of a display part is improving. In the attachment mechanism, the pressing bar 46 is connected to a lower end portion of an arm having an S shape as viewed from the side. Each arm has its width in the front-rear direction gradually reduced from the top to the bottom, and conversely, a thick structure is adopted at the base of the arm. As a result, it is possible to reliably exert an elastic action. On the back side of the pressing bar 46, a gap 46A opened downward is formed. The fabric is inserted into such a gap 46A. In addition, the personal dosimeter can be attached and detached by hooking a fingertip into the gap 46 from below and moving the pressing bar 46 away from the main body 12. A protrusion 46A extending in the horizontal direction is provided on the back side of the pressing bar 46, and the protrusion 46A is in contact with the front surface 12B of the main body 12. The protruding portion 46A is made of, for example, a rubber-like member that is softer than the pressing bar 46. As a result, the fabric can be securely clamped and the frictional force is increased, so that the wearing posture of the personal dosimeter can be stably maintained.

  As described above, each end has a shape like an ellipse extending in the vertical direction when viewed from the side, its upper end has a semicircular shape, and its lower end also has a semicircular shape. doing. A mounting member is provided so as to surround the periphery of such an end. Incidentally, the attachment portion of each arm is set at a position slightly above the front side of the main body 12 as shown in FIG. In any case, there is no pressing bar on the front side of the semiconductor sensor, that is, it is possible to avoid the problem of radiation attenuation due to the pressing bar. That is, the upper side of the main body 12 is opened above the intermediate level on the front side. Specifically, the center height level of the semiconductor sensor is set further above the upper end level of the slit formed on the back side of each arm.

  FIG. 6 shows a front view of the personal dosimeter. A cross section taken along the line AA shown in FIG. 6 is shown in FIG. 7, and a cross section taken along the line BB shown in FIG. 6 is shown in FIG.

  As shown in FIG. 7, the left mounting member 32 includes a left mounting end main body 49 and a connecting component 50. The inner side of the left attachment member 32 is a left end portion, and specifically includes a part of the rear case 52 and a part of the front case 54. The rear case 52 and the front case 54 are connected by screws 56 and 58. The heads of the screws 56 and 58 are located on the bottom surfaces of the holes 61 and 63, that is, the screws 56 and 58 are provided at positions lowered from the back surface level. The opening surfaces of the holes 61 and 63 are covered with the connecting component 50, and knobs 54 </ b> A and 54 </ b> B provided at the upper and lower ends of the connecting component 50 enter the holes 61 and 63. Therefore, since the screws 56 and 58 are concealed by the connecting part 50, the appearance can be improved, and the holes 61 and 63 are used as spaces for receiving the insertion end portions of the knobs 54A and 54B. There is no need to form a separate hole for the knobs 54A, 54B.

  In FIG. 8, a rear case 52 and a front case 54 constitute a main body case, and a substrate 58 is provided inside the main body case. The substrate 58 is elastically held by a holding structure described in detail later. An electronic circuit is mounted on the substrate 58, and a sensor unit 56 is disposed. The sensor unit 56 has an aluminum case and a semiconductor sensor disposed therein. Reference numeral 20 represents the radiation entry direction. Some electronic components are vulnerable to impacts, such as semiconductor sensors. In particular, when an impact is applied to the semiconductor sensor, there is a risk of erroneous counting. Therefore, in this embodiment, the elastic action is exhibited in the three holding structures that hold the substrate 58 as described below.

  Personal dosimeters are used indoors as well as outdoors. Therefore, it is necessary to provide a sufficient sealing property between the rear case 52 and the front case 54. For this reason, in this embodiment, such a special structure for improving the sealing performance is adopted, which will be described later.

  The connecting parts 48 and 50 shown in FIG. 4 are configured as members that connect the rear end portion of the upper hook portion and the rear end portion of the lower hook portion in the mounting member main bodies 47 and 49. Of course, it is also possible to form the members integrally. For example, as long as the clip member 34 can be reliably disposed, the attachment member can be formed of a member having an elastic action.

  According to the above-described attachment mechanism, it is possible to hold and hold the two end portions formed on both side surfaces of the main body, so that the attachment mechanism 14 itself can be firmly attached to the main body 12. Moreover, since the main part in the edge which the main body 12 has is covered with the attachment mechanism, or the attachment mechanism 14 is provided along such an edge part, the impact force from various directions with respect to the main body 12 is attached. The advantage that it can be mitigated by the mechanism 14 is obtained. In particular, according to the aspect in which the hook member is provided on the front side of the main body 12, two raised arms are provided on the front side of the main body 12, and a pressing bar that is warped is provided. Even in the case of collision, it is possible to receive the impact force by the elastic action of the two arms, etc., to relieve it and to protect the main body. For example, even when the main body 12 falls with its front surface facing down, there is an advantage that the impact force can be greatly relieved by the elastic action of the two arms. As a result, it is possible to protect the semiconductor sensor and the like.

  In addition, the pressing bar has a shape that spreads in the horizontal direction, that is, it can hold down the fabric with a relatively long path or a large area, so that the dosimeter can be worn in combination with the sandwiching action of the fabric by two slits. The advantage that the state can be stably maintained is obtained. Furthermore, in this embodiment, since the elastic action is exhibited by the two arms formed integrally with the two attachment members, there is an advantage that it is not necessary to provide a metal spring or the like. Since substantially uniform elastic urging force is applied to both ends of the pressing bar, the pressing bar can be reliably urged toward the apparatus main body, and there is no problem of scraping.

  As described above, according to the attachment mechanism, it is possible to provide an extremely practical personal dosimeter.

(2) Description of Holding Structure FIG. 9 shows a personal dosimeter with the front case removed. A substrate 58 is provided in the main body case, specifically, in the rear case 52. An electronic circuit is mounted on the substrate 58, and a sensor unit 56 is provided. The sensor unit 56 has a front aluminum case and a rear aluminum case, and a semiconductor sensor 60 is provided in a space enclosed by them. In order to fix the substrate 58 between the rear case 52 and the front case, three holding structures are provided in the present embodiment. Each holding structure has rubber legs 66, 68 and 70. The rubber leg 66 is provided above the center position of the substrate 58, the rubber leg 68 is provided on one lower side of the substrate 58, and the rubber leg 70 is provided on the other lower side of the substrate 58. That is, the substrate 58 is held by three points. 9 is a cross-sectional view of FIG. 10, which will be described below. In addition, the code | symbol 69 represents the battery storage chamber, and the opening part 67 is comprised as a space connected to it. A cap holder is arranged there. In FIG. 9, the attachment mechanism is not shown.

  In the cross-sectional view shown in FIG. 10, the substrate is disposed between the rear case 52 and the front case 54. In the example shown in FIG. 10, one holding structure is shown, which has rubber legs 66. The rubber leg 66 functions as a spacer and a bush as a vibration isolating member, which is a one-piece member. The enlarged view of the part shown by the code | symbol 72 is FIG. 11 demonstrated later.

  A seal portion is constituted by the opening edge of the rear case 52 and the opening edge of the front case 54. Specifically, the seal portion includes a seal groove 62 provided on the front case 54 side, a packing 64 disposed therein, and a pressing body formed on the rear case 52 side. These will be described in detail later. Incidentally, the enlarged view of the part shown by the code | symbol 74 is equivalent to FIG.12 and FIG.13.

  In FIG. 11, a substrate 58 is provided between a lower rear case 52 and an upper front case 54 in a horizontal state in FIG. Incidentally, the vertical direction in FIG. 11 is the front-rear direction when the personal dosimeter is in use.

  The substrate 58 is held in the main body case by the holding structure 76. The holding structure 76 includes a first holding part 78 and a second holding part 80 in view of its function. The first holding portion 78 holds the substrate 58 on the first surface (front surface) 58A side, and the second holding portion 80 holds the substrate 58 on the second surface (rear surface) 58B side. is there. The first holding portion 78 includes a support column 92, a projecting portion 82 formed at an end of the support column 92, and a contact surface 92 </ b> A that forms a peripheral surface of the projecting portion 82. The second holding portion 80 has a protruding portion 86 that is erected from the rear case 52 and a contact surface around the protruding portion 86 on the rear case inner surface 52A.

  A rubber leg 66 made of an elastic member, specifically, rubber, is provided across the first holding part 78 and the second holding part 80. The rubber leg 66 functions as a spacer between the first surface 58A of the substrate 58 and the contact surface 92A, and exerts a positioning action, and a neck 66B that is connected to the through hole 58C of the substrate 58. The body 66C functions as a spacer and exhibits a positioning action between the second surface 58B of the substrate 58 and the inner surface 52A of the rear case 52.

  This will be described in more detail. A support column 92 is provided that stands up from the inner surface of the front case 54 and extends toward the rear case 52. The support column 92 has a cylindrical shape, and a protruding portion 82 is formed as a cylindrical portion protruding from the end surface toward the rear case 52 side. The end surface of the protrusion 82 is close to the first surface 58 </ b> A of the substrate 58. That is, the end face level and the level of the first face 58A are substantially the same or close to each other. As described above, the periphery of the projecting portion 82 of the support column 92 is the contact surface 92A, and the end surface of the head 66A is in contact with the contact surface 92A.

  The head 66A has a slightly tapered shape toward the front case 54, and the head 66A has a size and shape that penetrates the through hole 58C. A well-like opening 84 is formed in the head 66A, and the protrusion 82 is inserted into the well. A slight gap is generated between the end surface of the protrusion 82 and the bottom surface of the opening 84.

  As described above, since the head 66A is disposed between the contact surface 92A and the first surface 58A, the impact from the front case 54 is mitigated by the head 66A. Since the bottom surface of the opening 84 matches the level of the first surface 58A and the end surface of the hard protrusion 82 approaches the vicinity of the first surface 58A, the spacers or the vibration-proofing action are exerted on the head 66A. The lateral and vertical displacements of the substrate 58 with respect to the front case 54 are limited within a certain range. As a result, it is possible to effectively avoid the problem that the board 58 and the components mounted thereon collide with surrounding members. The above is the operation of the first holding part 78.

  A through hole 58C as a circular opening is formed in the substrate 58, and the head 66A is inserted into the substrate 58 from the second surface 58B side. Then, as shown in FIG. 1, the head 66A protrudes toward the first surface 58A, and as a result, the annular groove of the neck 66B is fitted into the through hole 58C. Thereby, the rubber legs 66 are integrated with the substrate 58. Since the rubber legs 66 are made of an insulating member, the insulation of the substrate 58 is also ensured. When the rubber legs 66 are attached to the substrate 58, the above-described fitting method is used, that is, screwing or the like is unnecessary, so that the number of parts can be reduced and the assemblability can be improved. This is also a matter that can be pointed out similarly for fixing the rubber legs 66 to the front case 54 and the rear case 52.

  The body 66C is a portion provided between the second surface 58B and the abutting surface of the inner surface 52A, and exhibits a spacer function, a vibration isolating function, and a positioning function. The horizontal sectional size of the body 66C is slightly larger than the horizontal sectional size of the head 66A. The thickness in the vertical direction of the body 66C is considerably larger than the thickness in the vertical direction of the head 66A.

  The body 66C has an opening 90 facing downward in FIG. 11, and a hard protrusion 86 is inserted into the opening. The protrusion 86 has a well-shaped hole 88 at the center thereof. The opening 90 has a shape that gradually becomes deeper toward the bottom surface, that is, the upper surface in FIG. 11, and the protrusion 86 has a shape that tapers upward in accordance therewith. The protrusion 86 has a cylindrical or conical shape. The end surface of the protrusion 86 is separated from the second surface 58B to some extent, and a certain thickness exists between the bottom surface of the opening 90 and the second surface 58B.

  Therefore, according to the body 66C, vibration transmitted from the rear case 52 to the substrate 58 can be effectively mitigated, and insulation can be ensured. In the state where the neck 66B is fitted in the through hole 58C, the protruding portion 86 which forms a part of the rear case 52 is inserted into the opening 90, so that a horizontal positioning action is obtained in FIG. Can do. Moreover, since the protrusion part 86 has a taper form and the opening part 90 has a deep form, insertion of the protrusion part 86 to the opening part 90 is easy. In the body 66C, there is a certain thickness between the second surface 58B and the end surface of the projecting portion 86 or the side surface of the opening 90, and considering the elastic deformation there, the substrate 58 with respect to the rear case 52. It can be said that the lateral displacement and the longitudinal displacement in are allowed to some extent. Therefore, since there is such a degree of freedom, the substrate 58 is securely fixed inside the two cases even if there is a positional deviation between the front case 54 and the rear case 52 or a molding error in each case. Is possible. The above is the operation of the second holding unit 80. Incidentally, the upper portion (right end portion in FIG. 11) of the front case 54 is a partition wall 54B, which constitutes the bottom wall of the groove portion that accommodates the display unit. A seal groove 62 is formed in the partition wall 54B, and a packing 64 is fitted therein.

  As described above, according to the holding structure in the present embodiment, it is possible to reduce the impact force on the substrate by using the rubber legs. In particular, since the lateral displacement and longitudinal displacement of the substrate are limited to some extent with respect to the case on one side, it is possible to avoid the substrate itself or components on the substrate from colliding with surrounding members. Further, on the second surface side of the substrate, there is a body having a thickness, which allows a certain amount of lateral displacement and longitudinal displacement in the substrate, so there is no positional deviation or molding error between the two cases. Even if it can be absorbed by the body. In addition, since there is a body having a thickness as a whole rubber leg, the elastic action of the whole rubber leg can be sufficiently exhibited. At the time of assembly, the substrate and the rubber leg can be integrated by simply inserting the head into the through hole, and the engagement relationship with each case can be established by fitting the protrusion and the opening. Advantages such as reduction in the number of parts and improvement in assembly workability can be obtained.

(3) Description of Seal Structure FIG. 12 shows a seal structure according to this embodiment. In particular, the opening edges of the rear case 52 and the front case 54 are shown as enlarged views. The front case 54 is formed with a seal groove 62 as a rectangular groove. As will be described later, the seal groove 62 has a three-dimensional shape and is a closed loop groove. A packing 64 is disposed in the seal groove 62. The packing 64 is a seal member, and is made of an elastic member such as rubber. The packing 64 has the same three-dimensional shape as the three-dimensional shape of the seal groove 62 and has a closed loop shape. A first surface of the packing 64, specifically, a surface 64B that is in contact with the bottom surface of the seal groove 62 has a mountain shape. This is to improve the adhesion between the first surface 64B and the bottom surface of the seal groove 62 when the packing 64 is crushed. The surface on the pressing side of the packing 64, that is, the second surface 64A constitutes a flat surface. The pressing action by the pressing body 65 reaches such a flat surface 64A.

  A pressing body 65 is formed on the rear case 52. The pressing body 65 is formed in an inner surface 52A shape, and specifically includes an offset portion rising from the inner surface 52A and two protrusions 94 and 96 formed on the end surface of the offset portion. Such a row of ridges is for enhancing the crushing action on the packing 64. The protrusion 94 is an outer protrusion, and the protrusion 96 is an inner protrusion. In this way, multiple ridge rows are formed from the outside to the inside. In the example shown in FIG. 12, the cross sections of the protrusions 94 and 96 have a semicircular shape, but an oval shape or other shapes may be adopted.

  FIG. 13 shows the operation in the seal structure. As described above, the packing 64 is accommodated in the seal groove 62, and when the rear case 52 is joined to the front case 54, the pressing body 65 enters the seal groove 62, and in particular, the two protrusions 94. 96 push the second surface of the packing 64 deeply into the groove.

  In such a state, coupled with the shape of the first surface of the packing 64, the packing 64 is strongly crushed in the seal groove 62, that is, the packing 64 is in close contact with the inner surface of the seal groove 62, and the pressing body. Since the contact state is completely formed between the gasket 64 and the packing 64, the sealing performance can be extremely enhanced. For example, even if there is an incomplete sealability between the outer protrusion 94 and the packing 64, the sealability can be ensured by the protrusion 96 on the inner side. The same applies to the reverse. It is desirable to provide two protrusions 94 and 96 for the convenience of production. Each protrusion 94 and 96 is a protrusion extending along the direction of the seal groove 62. The pressing body 65 has the same three-dimensional shape as the three-dimensional shape of the seal groove 62 and has a closed loop configuration.

  14A shows a front case 54, FIG. 14B shows a packing 64 having a three-dimensional shape, and FIG. 14C shows a rear case 52.

  As shown in (A), the front case 54 has a cap holder 104. Specifically, the cap holder 104 is integrally formed as a part of the front case 54. The inside of the cap holder 104 is a deformation cavity, and a cap is fitted therein. As will be described later, a display housing portion is integrally formed in the front case 54.

  In the rear case 52 shown in (C), a concave portion 104 </ b> A having a semicircular shape is generated corresponding to the cap holder 104. Moreover, the recessed part 100 for receiving the protrusion part of said indicator accommodating part has arisen.

  The row of ridges as the pressing body 65 has a three-dimensional shape as shown in the figure, and the row of ridges includes a portion 65A in the recess 100 and a portion 65B in the recess 104A. Have. Such portions 65A and 65B have portions that are parallel to the joining direction of the two cases. On the other hand, in the present embodiment, as described above, the pressing body 65 as the row of ridges is formed, and the surface shape of the packing 64 is operated. It is possible to increase. Incidentally, in the packing 64, the part fitted in the part 65A mentioned above is shown by 64A, and the part fitted in the part 65B mentioned above is shown by 64B. Portion 65A can be referred to as a lower rectangular portion and portion 65B can be referred to as a lower semicircular portion.

  FIG. 15 shows an exploded perspective view of a personal dosimeter viewed from different directions. (A) shows the rear case 52, (B) shows the packing 64, and (C) shows the front case 54. In FIG. 15, the direction indicated by the arrow is the forward direction from the living body side. As shown in (C), a seal groove 62 is formed in a three-dimensional shape along the opening edge of the front case 54. The front case 54 includes a display housing portion 102, and a part of the front case 54 protrudes in a rectangular shape on the rear case 52 side. Further, the front case 54 includes a cylindrical cap holder 104. The seal groove 62 is formed so as to go around the upper side of each such protruding portion. Incidentally, reference numeral 106 represents a battery accommodating chamber.

  In the packing 64 shown in (B), the upper rectangular portion corresponding to the display housing portion is denoted by reference numeral 64A. A portion corresponding to the cap holder 104 is indicated by an upper semicircular portion 64B. When the two cases 52 and 54 are joined with the packing 64 fitted in the seal groove 62, the two protrusions formed on the rear case 52 side enter the seal groove 62, thereby strengthening the packing 64. Will be pressed. As a result, even if there is a portion in the packing 64 that is parallel to the joining direction of the two cases, it is possible to effectively prevent deterioration of the sealing performance there. That is, even when the sealing performance is insufficient at one ridge, it is possible to ensure the sealing performance at the other ridge.

  In the above embodiment, the seal path is set so as to exceed the edge of the portion protruding from the front case to the rear case side. This avoids complication of the seal structure in the case where such a protruding portion is constituted by another piece. In addition, the number of parts is reduced. In particular, in a cap holder, it is necessary to securely seal around the cap as a detachable part, and if a crack structure is adopted for such a part, the sealing performance is likely to deteriorate. Since the seal path is set so as to go around the outside without being divided, a unique seal member can be arranged inside the cap holder, and the problem of deterioration of the sealing performance between the cases does not occur. Moreover, even if the seal path is set so as to go around the surface of such a protruding portion, the sealing performance as a whole can be maintained by the action of the two protrusions as described above.

  Incidentally, a mold or the like can be used for manufacturing a packing having a three-dimensional shape. In the embodiment described above, the two cases are connected after the packing is disposed in the seal groove. In that case, it is possible to connect the two cases using only four screws. In addition, as described above, these screw threads are concealed in a part of the attachment member, and the appearance when viewed from the outside can be improved.

  In the above embodiment, a structure other than the above can be adopted as the structure for pressing the seal member. For example, only one protrusion may be provided. Even with such a configuration, the seal member can be locally pressed to increase the deformation thereof, and thus the sealing performance can be improved. Moreover, you may make it provide three or more protrusions. However, if too many ridges are provided, it is equivalent to a planar pressing action, so it is desirable to provide double ridges as described above. Incidentally, it is desirable to form each corner portion with a slight roundness in a three-dimensional loop path.

  10 personal dosimeter, 12 body, 14 attachment mechanism, 16 right end, 18 left end, 30 right mounting member, 32 left mounting member, 34 clip member, 42 right arm, 44 left arm, 46 pressure bar, 52 rear case, 54 front case, 62 seal groove, 64 packing, 65 pressing body (row row) 66 rubber leg, 66A head, 66B neck, 66C body, 76 holding structure, 78 first holding portion, 80 second holding portion.

Claims (7)

A body case composed of a first case and a second case arranged in the front-rear direction;
A substrate provided in the main body case and mounted with a radiation sensor;
A plurality of holding structures for elastically holding the substrate between the first case and the second case;
Including
At least one of the plurality of holding structures is
A first holding portion provided on the inner side of the first case and having a first contact surface and a first protrusion;
A second holding portion provided inside the second case and having a second contact surface and a second protrusion;
A portion that is inserted through the through hole of the substrate and protrudes toward the first surface of the substrate and has a first opening into which the first protrusion is inserted, and the first surface of the substrate and the first contact A head that functions as a spacer between the contact surface, a neck that is connected to the head and located inside the through hole, and a portion that is connected to the neck and into which the second protrusion is inserted. A body having two openings and a body functioning as a spacer between the second surface of the substrate and the second contact surface;
A personal dosimeter characterized by comprising: The personal dosimeter according to claim 1,
The front end of the first protrusion is closer to the substrate than the front end of the second protrusion, and the thickness of the head in the front-rear direction is thinner than the thickness of the body in the front-rear direction.
A personal dosimeter characterized by that. The personal dosimeter according to claim 1 or 2,
The first holding portion has a support column that stands up from the inner surface of the first case as a part of the first case,
The first protrusion is formed at the tip of the column,
The first contact surface is formed around the first projecting portion at the tip of the support column.
A personal dosimeter characterized by that. The personal dosimeter according to any one of claims 1 to 3,
The second protruding portion constituting the second holding portion protrudes from the second case as a part of the second case,
The second contact surface constituting the second holding portion is a part of the inner surface of the second case and is around the base of the second protrusion.
A personal dosimeter characterized by that. The personal dosimeter according to any one of claims 1 to 4,
The cross section of the first projecting portion has a tapered shape from the first surface of the substrate to the first case side. The personal dosimeter according to any one of claims 1 to 5,
The level of the tip surface of the first protrusion is substantially equal to the level of the first surface;
A personal dosimeter characterized by that. The personal dosimeter according to any one of claims 1 to 6,
The second protrusion has a tapered shape from the inner surface of the second plate to the substrate side,
The second opening is deep from the opening surface to the bottom surface,
A personal dosimeter characterized by that.

Images