Patent Publication Number: US-2007109136-A1

Title: Portable alarm device

Description:
CROSS REFERENCE TO RELATED APPLICATION  
      This application corresponds to the Japanese Patent Application No. 2005-330575 filed with the Japan Patent Office on Nov. 15, 2005, and the whole disclosure of the application is incorporated in this application by citation.  
     BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      This invention relates to a portable alarm device.  
      2. Description of Related Arts  
      Recently, various kinds of articles of criminal prevention have been proposed for informing a third person of a criminal offense of a robber, ruffian or the like when a user meets with the criminal offence.  
      For example, alarm devices have been proposed in which a strap of a cell phone and a criminal preventing buzzer are integrated and the criminal preventing buzzer sounds by pulling out the strap. In such a kind of alarm device, usually an improper operation preventing button is provided and the strap cannot be pulled out without simultaneously pressing the improper operation preventing button (see, for example, Japanese Utility Model Registration Publication No. 3086405 and Japanese Unexamined Patent Publication No. 1997-293186).  
      However, it is difficult for a user in a fright to seek the position of the improper operation preventing button and press the same well. Therefore, it is supposed that the strap cannot be pulled out and the criminal preventing buzzer cannot be operated.  
      An object of the present invention is to provide a portable alarm device capable of being surely operated in an emergency.  
     SUMMARY OF THE INVENTION  
      In order to achieve the abovementioned object, a portable alarm device according to an embodiment of the present invention comprises a cylindrical main body containing therein an alarm sound emitting unit and a switch for operating the alarm sound emitting unit, and an operation member which closes the switch by being detached from the main body in an axial direction of the main body. This portable alarm device further comprises a locking member provided in the main body and displaceable between a locking position for preventing the detachment of the operation member and a unlocking position for allowing the detachment of the operation member, and an actuating member for driving a locking member to the unlocking position in accompany with either one of an action of grasping the main body in a radial direction by hand and an action of relative movement of the operation member and the main body grasped by hand in the axial direction of the main body.  
      In this embodiment of the present invention, the actuating member is displaced during the basic action of detaching the operation member and the main body from each other in the axial direction with grasping the main body, and as a result, the lock of the operation member and the main body can be easily released. In comparison with a case in which a user has to separately seek an unlocking button or the like and press the button, the necessary action in this embodiment is remarkably rapid and in addition, has a higher sureness. The main body detached from the operation member can be thrown far away without need of passing to the other hand and the like actions.  
      The operation member preferably includes a pin directly or indirectly attached with a string, belt or chain to be passed around a belonging or a neck. Thereby, since the pin is held by the portable member or the like, the pin and the main body can be easily detached from each other by pulling the main body.  
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a sectional view of a portable alarm device according to an embodiment of the present invention.  
       FIG. 2  is a sectional view of the portable alarm device seen from another angle.  
       FIG. 3  is a schematical perspective view of a pair of locking plates and a pin.  
       FIG. 4  is a block diagram showing an electric structure of the portable alarm device.  
       FIG. 5  is a sectional view of the pin.  
       FIG. 6  is a perspective view showing a way of treating the portable alarm device.  
       FIGS. 7A and 7B  are process views showing unlocking operation with respect to the pin.  
       FIGS. 8A and 8B  respectively are a plan view and a side view of a portable alarm device according to another embodiment of the present invention.  
       FIGS. 9A and 9B  respectively are a cross sectional view and a longitudinal sectional view of the portable alarm device of  FIG. 8 .  
       FIGS. 10A and 10B  respectively are a plan view and a side view of a portable alarm device according to a further another embodiment of the present invention.  
       FIGS. 11A and 11B  respectively are a cross sectional view and a longitudinal sectional view of the portable alarm device of  FIG. 10 .  
       FIGS. 12A and 12B  respectively are a plan view and a side view of a portable alarm device according to a further another embodiment of the present invention.  
       FIGS. 13A and 13B  respectively are a cross sectional view and a longitudinal sectional view of the portable alarm device of  FIG. 12 , and  FIG. 13C  is a schematical sectional view of a main part of the portable alarm device.  
       FIG. 14  is a side view of a portable alarm device according to a further another embodiment of the present invention.  
       FIGS. 15A and 15B  respectively are a cross sectional view and a longitudinal sectional view of the portable alarm device of  FIG. 14 , and  FIG. 15C  is a schematical sectional view of a main part of the portable alarm device.  
       FIGS. 16A and 16B  respectively are a plan view and a side view of a portable alarm device according to a further another embodiment of the present invention.  
       FIGS. 17A and 17B  respectively are a cross sectional view and a longitudinal sectional view of the portable alarm device of  FIG. 16 .  
       FIG. 18  is a side view of a portable alarm device according to a further another embodiment of the present invention.  
       FIG. 19  is a sectional view of a main part of the portable alarm device of  FIG. 18 .  
       FIG. 20  is a pattern side view of a portable alarm device according to a further another embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      Now, preferred embodiments of the present invention will be described with reference to the appended drawings.  
       FIG. 1  is a schematical sectional view of a portable alarm device according to an embodiment of the present invention, and  FIG. 2  is a sectional view of the portable alarm device seen from another angle. Referring to  FIGS. 1 and 2 , the portable alarm device  1  comprises a main body  2  and a pin  3  as an operation member detachable from the main body  2 .  
      As shown in  FIG. 3 , the pin  3  includes a top portion  5  having a string stabbing hole  4 , a shaft body  6  and a switch press-down portion  7  provided at an end of the shaft body  6 . A string  8  passed around a belonging or a neck is passed through the string stabbing hole  4 . The shaft body  6  includes a first wide portion  6   a  formed in continuation with the top portion  5 , a second wide portion  6   b  formed in continuation with the switch press-down portion  7  and a narrow portion  6   c  provided between the first wide portion  6   a  and the second wide portion  6   b.    
      Referring to  FIG. 2 , the main body  2  comprises a box-shaped body having a first portion  2   a  constituting mainly a lower portion and a second portion  2   b  as an actuating member (radially displacing member) constituting mainly an upper portion. As shown in  FIGS. 1 and 2 , the first portion  2   a  has an extended portion  2   d  upwardly extended in a circumferential portion. The second portion  2   b  allows the extended portion  2   d  of the first portion  2   a  to intrude into the circumferential portion thereof. The second portion  2   b  is provided not throughout the whole circumference but on the almost whole region in the direction of the circumference. In the first portion  2   a  of the main body  2 , a battery  9  is provided. As the battery  9 , for example, a plurality of button type butteries in each of which a plurality of rows is used. Further, at the lowest portion of the first portion  2   a , a speaker  10   c  of a below mentioned alarm sound emitting unit  10  is held. At the bottom of the main body  2 , minute through holes are provided for delivering sounds from the speaker  10   c  to the outside.  
      The second portion  2   b  as the actuating member is made of a resiliently deformable material such as ABS resin or other synthetic resins. And this second portion  2   b  as the actuating member functions also as a biasing member for returning both of the below mentioned locking plates as locking members to locking positions. However, a biasing member may be provided separately from the second portion  2   b.    
      At the top end portion of the second portion  2   b  of the main body  2 , a lens  11  is provided for passing the light from a light source  14 . Provided at the central portion of the lens  11  is a shaft body penetrating hole  11   a  for inserting the shaft body  6  of the pin  3  therethrough. A sealing agent in such an amount as not hindering the pin  3  from being detached may be filled between an inner circumferential surface of the shaft penetrating hole  11   a  and the pin  3 .  
      In the second portion  2   b  of the main body  2 , a circuit substrate  12  is contained. The circuit substrate  12  is held by a support wall  2   c  as a third portion of the main body  2  formed integrally with the second portion  2   b  of the main body  2 . Packaged on the circuit substrate  12  are the alarm sound emitting unit  10 , a switch  13  for actuating the alarm sound emitting unit  10 , the light source  14  such as a high brightness LED, a time measuring section  15  as a time measuring unit for measuring the time instant and the like.  
      Referring to  FIG. 1 , the alarm sound emitting unit  10  comprises an audio signal emitting section  10   a  for emitting audio signals, an amplifier  10   b  for amplifying a signal emitted from the audio signal emitting section  10   a , and the speaker  10   c  for converting the audio signal amplified by the amplifier  10   b  into a sound. A loud sound and voice such as “Help!” of a female voice is outputted from the speaker  10 .  
      Referring to a block diagram of  FIG. 4 , a control section A constituted by a CPU, RAM, ROM and the like includes the abovementioned audio signal emitting section  10   a , an blinking signal emitting section  19 , the abovementioned time measuring section  15  and the like. The blinking signal emitting section  19  is connected through an amplifier  20  to the light source  14 . Further, A backup electric source  21  provided in the control section A is connected to the time measuring section  15  so that the time measuring section  15  can be driven without any power supply from the battery  9 . Further, an unvolatile memory  22  is connected to the time measuring section  15 , and a time measurement data (time instant) outputted from the time measuring section  15  on closing the switch  13  can be stored in the unvolatile memory  22 .  
      As shown in  FIG. 1 , contained in the second portion  2   b  of the main body  2  is a lock member  16  for preventing the pin  3  from being detached so as to prevent improper operation of the switch  13 . As shown in  FIGS. 2 and 3 , the lock member  16  comprises a pair of locking plates  16   a ,  16   b  one end of each of which is connected to the inside surface of the second portion  2   b  as the resiliently deformable actuating member.  
      The pair of locking plates  16   a ,  16   b  are relatively displaceable in a direction of a relative movement (corresponding to a radial direction Y of the main body  2 ) perpendicular to a detachment direction X of the pin  3  in accompany with resilient deformation of the second portion  2   b  of the main body  2 . As shown in  FIG. 3 , each of the locking-plates  16   a ,  16   b  includes a pin detachment hole  17  and through which the second wide portion  6   b  of the pin  3  can penetrate, and a pin detachment preventing channel  18  extended from the pin detachment hole  17  through which the second wide portion  6   b  of the pin  3  cannot penetrate but the narrow portion  6   c  of the pin  3  can penetrate. Referring to  FIGS. 3 and 5 , widths of the wide portions  6   a ,  6   b  and the narrow portion  6   c  of the pin  3  mean their widths in a direction Z perpendicular to the detachment direction X of the pin  3  and the direction of the relative movement (radial direction Y) of the locking plates  16   a ,  16   b.    
      A feature of this embodiment is that, as shown in  FIG. 6 , by grasping with hands the second portion  2   b  of the main body  2  as the resiliently deformable actuating member, the pin detachment holes  17  of the pair of locking plates  16   a ,  16   b  change their state from a mutually separated state as shown in  FIG. 7A  to a mutually superposed position as shown in  FIG. 7B , so that the pin  3  can be detached.  
      In other words, only by grasping with hands the second portion  2   b  of the main body  2  as the resiliently deformable actuating member, the locking member  16  is unlocked as shown in  FIG. 6 , and the user has only to pull out the main body  2  from the pin  3  by the grasping hands. Since the locking member  16  can be unlocked only by the action of grasping the main body  2 , the action of the user is remarkably more rapid and surer in comparison with the case of requiring other actions for unlocking the locking member  16 .  
      A strength of grasping the second portion  2   b  of the main body  2  as the resiliently deformable actuating member for unlocking the locking member  16  can be set at such a level that no improper operation occurs in consideration with women&#39;s or children&#39;s powers. With respect to the resiliently deformable portion, the level of the grasping strength can be easily set. Further, in the case of the resiliently deformable portion, on leaving the hand from the main body  2  after detaching the pin  3 , the locking plates  16   a ,  16   b  return to the locking position. Therefore, even if the suspicious person or the like manages to mount the pin  3  to the main body again, he cannot mount the pin  3  in this state, which gives more time to a victim for running away.  
      Further, the string  8  to be passed around a belonging or a neck is attached to the pin  3  as the operation member and the pin  3  is held on the side of the belonging, therefore, when the main body  2  is pulled, it can be easily pulled away advantageously.  
      Further, a way of treating this portable alarm device  1  is that, when a suspicious person attacks a victim, the victim has only to detach the main body  2  from the pin  3  and throw the main body  2  emitting a loud alarm voice and sound away from the suspicious person. In this case, the suspicious person wavers in his determination as to whether he will come toward the victim or go toward the main body  2  thrown away and emitting a loud alarm voice and sound and hesitates for a moment, during which the victim has a chance of escape.  
      The sound emitted from the speaker  10   c  is preferably at full blast, since such a sound gives a psychological pressure to a suspicious person. In the case that the battery  8  comprises six button-type batteries, a sound at full blast can be maintained for about 15 minutes.  
      Further, the sound emitted from the speaker  10   c  may become gradually louder, and this is preferable because a strong psychological pressure can be also given to a suspicious person.  
      Further, since the time measurement data outputted from the time measuring section  15  on closing the switch  13  have been stored in the unvolatile memory  22 , the following advantage can be obtained. That is, when the main body  2  is recovered after some time from an occurrence of an accident, the time of the occurrence of the accident can be precisely obtained on the basis of the data (time instant) read out from the unvolatile memory  22  of the main body  2 . A terminal for reading out the data stored in the unvolatile memory  22  may be provided as an external interface.  
      Further, the abovementioned time measuring section  15  is for measuring the time instant, but it may be a time measuring section for measuring a lapse time after the switch  13  is closed. In such a case, when the main body  2  is recovered after some time from an occurrence of an accident, a lapse time after the occurrence of the accident can be obtained on the basis of an output from the time measuring section  15 , and as a result, the time of the occurrence of the accident can be also precisely obtained. In this case, such an arrangement is allowable that a content stored in the unvolatile memory  22  is rewritten on the basis of an output from the time measuring section  15  and data relating to the lapse time are read out from the unvolatile memory  22 . In this case, a terminal for reading out the data stored in the unvolatile memory  22  may be provided as an external interface.  
       FIGS. 8 and 9  show another embodiment of the present invention. Referring to  FIGS. 8 and 9 , this embodiment is different from the embodiment of  FIG. 1  mainly in the following points 1) to 3).  
      1) As shown in  FIG. 9A , a second portion  23  of the main body  2  is a movable portion guided by a guide groove  24  formed in the first portion  2   a  of the main body  2  to move in the radial direction of the main body  2 , and constitutes an actuating member (radially displacing member). In concrete, as shown in  FIG. 9B , an upper end of the second portion  23  is pivotally supported by the first portion  2   a  through a pivot  25 . However, since a movable range of the upper end portion of the second portion  23  is very small with respect to its rotation radius, the second portion  23  is displaced substantially in the radial direction of the main body  2 . Further, a biasing member  26  comprising a compression coil spring biases the second portion  23  outwardly in the radial direction.  
      2) Only a single locking plate  16   a  is provided as a locking member. This locking plate  16   a  has the same structure as the locking plate  16   a  of  FIG. 3  and has a pin detachment hole  17  and a pin detachment preventing channel  18 .  
      3) A wire-type transmitting mechanism  27  is provided for transmitting an action of the second portion  23  as the actuating member to the locking member  16   a . The wire-type transmitting mechanism  27  comprises a wire  28  one end  28   a  of which is secured to the locking plate  16   a  with the other end secured to a stay  29  fixed to the second portion  23 , and a plurality of guide pins  30  for guiding the wire  28 .  
      In this embodiment, similar effects to those of the embodiment of  FIG. 1  can be obtained. In other words, when a user performs a series of actions of downwardly pulling the main body  2  with grasping the same in an emergency, the second portion  23  is inwardly pushed in the radial direction by the action of grasping the main body  2 , and in accompany with this, the locking plate  16   a  is displaced through the wire-type transmitting mechanism  27 , so that the lock is released. Therefore, the lock is easily and surely released.  
       FIGS. 10 and 11  show a further another embodiment of the present invention. Referring to  FIGS. 10 and 11 , this embodiment is different from the embodiment of  FIG. 1  mainly in the following points 1) to 4).  
      1) In the embodiment of  FIG. 1 , the second portion  2   b  of the main body  2  as the actuating member is a resiliently deformable member. However, in this embodiment, a pair of second portions  31  opposed in the radial direction of the main body  2  is movable portions displaceable in the radial direction of the main body  2  by guide of guide grooves  32  provided on the first portion  2   a  of the main body  2 , and constitute the actuating member (radially displacing member). Each of the second portions  31  is biased outwardly in the radial direction by a corresponding biasing member  33  comprising a compression coil spring  33 .  
      2) The pair of second portions  31  is respectively connected through connecting portions  34  to the corresponding locking plates  16   a ,  16   b.    
      3) A dome-shaped cover  35  covering an upper portion of the main body  2  is provided integrally with the pin  3 . This cover  35  is respectively engaged with outer end portions of the locking plates  16   a ,  16   b  so as to constitute labyrinth structures  36  respectively, thereby its tightness is improved. When the lock with respect to the pin  3  is released, the locking plates  16   a ,  16   b  are respectively displaced forwardly (inwardly in the radial direction of the main body  2 ) to release the engagement between the locking plates  16   a ,  16   b  and the cover  35 . Therefore, the cover  35  does not prevent the detachment of the pin  3  from the main body  2 .  
      4) An attachment hole  35   a  for attaching a string is provided in a top portion of the cover  35 .  
      In this embodiment, similar effects to those of the embodiment of  FIG. 1  can be obtained. In other words, when a user performs a series of actions of downwardly pulling the main body  2  with grasping the same in an emergency, both of the second portions  31  are inwardly pushed in the radial direction by the action of grasping the main body  2 , and in accompany with this, both of the locking plates  16   a ,  16   b  are displaced, so that the lock is released. Therefore, the lock is easily and surely released.  
       FIGS. 12 and 13  show a further embodiment of the present invention. Referring to FIGS.,  12  and  13 , this embodiment is different from the embodiment of FIG.  11  mainly in the following points 1) to 3).  
      1) In the embodiment of  FIG. 11 , the locking plates  16   a ,  16   b  to be engaged with the pin  3  are used, but in this embodiment, these locking plates are not used and a pair of locking portions  38  are provided which are radially opposed on an inner circumferential surface of an open end portion of a dome-shaped cover  37  as shown in  FIG. 13B . As shown in  FIG. 13C , the each locking portion  38  comprises a seizing groove, and this seizing groove seizes a locking projection  39  provided on a side portion of the main body  2 , thereby preventing the cover  37  and the pin  3  integrally attached to the cover  37  from being detached from the main body  2 . The locking portion  38  may be a locking projection to be seized by the seizing groove of the main body  2 .  
      2) Further, as shown in  FIG. 12 , the cover  37  is provided with a pair of radially opposed press handling portions  40  as the actuating member (radially displacing member). The mutually opposed direction of the pair of press handling portions  40  and the mutually opposed direction of the abovementioned pair of locking portions  38  are perpendicular to each other. The pair of press handling portions  40  respectively comprises resilient tongue pieces defined by channel-shaped cut portions formed in the cover  37 . The resilient tongue piece is elongated toward the open end side of the cover  37  in the manner of a cantilever.  
      3) The cover  37  comprises a resiliently deformable member. By pushing the pair of press handling portions  40  inwardly in the radial direction of the cover  37  (i.e. by reducing the distance between the pair of press handling portions  40 ), the distance between the pair of the locking portions  38  of the cover  37  becomes larger, so that the lock by each of the locking portions  38  is released.  
      Similar to the case of the embodiment of  FIG. 11 , an attachment hole  35   a  for attaching a string is provided in the top portion of the cover  37  in this embodiment. In this embodiment, similar effects to those of the embodiment of  FIG. 11  can also be obtained.  
       FIGS. 14 and 15  show a further another embodiment of the present invention. Referring to  FIGS. 14 and 15 , this embodiment is different from the embodiment of  FIG. 9  mainly in the following points 1) to 3).  
      1) In the embodiment of  FIG. 9 , the second portion  23  as the actuating member is displaced in the radial direction Y of the main body  2 , but in this embodiment, a second portion  41  as the actuating member (radial displacement member) comprises a cylindrical cover partly covering the outer circumferential surface of the first portion  2   a  of the main body  2 , and this second portion  41  comprising the cylindrical cover is displaceable in the axial direction W of the main body  2 .  
      2) As shown in  FIG. 15A , the second portion  41  comprising the cylindrical cover is supported by guide structures  42  formed on the first portion  2   a  of the main body  2  so as to be displaceable in the axial direction W of the main body  2 . In concrete, as shown in  FIG. 15C , the guide structures  42  may be a guide ridge elongated in the axial direction W of the main body  2  and may be so adapted to be fitted into a groove  44  of a groove forming member  43  formed on the inner circumferential surface of the second portion  41 . Otherwise, the guide structure  42  may be a guide groove elongated in the axial direction of the main body  2  and may be so adapted to be fitted with a ridge provided on the second portion  41 .  
      3) A stay  45  is fixed to the groove forming member  43  of the second portion  41  comprising the cylindrical cover. And the stay  45  and the locking plate  16   a  are connected to each other through the wire  28  of the wire-type transmitting mechanism  27 . Further, a biasing member  47  comprising a compression coil spring is interposed between a spring seat  46  formed on the first portion  2   a  of the main body  2  and the abovementioned stay  45 . The biasing member  47  biases the second portion  41  through the stay  45  into a posture corresponding to the locked state (to the upper position in  FIG. 15B ).  
      According to this embodiment, when a user performs a series of actions of downwardly pulling the second portion  41   b  comprising the cover of the main body  2  with grasping the same in an emergency, the locking plate  16   a  is displaced through the wire  28  by the action of pulling the main body  2 , so that the lock is released. Therefore, the lock is easily and surely released.  
       FIGS. 16 and 17  show a further another embodiment of the present invention. Referring to  FIGS. 16 and 17 , this embodiment is different from the embodiment of  FIG. 15  mainly in the following points 1) to 3).  
      1) In the embodiment of  FIG. 15 , the second portion  41  comprising a cover constitutes the actuating member for releasing the lock. However, in this embodiment, instead of such an actuating member, an actuating member  48  (radially displacing member) which can be grasped together with the main body  2  is provided. The actuating member  48  comprises a vertically elongated long member formed to protrude from a part of the outer circumferential surface of the main body  2 . A finger recess  49  is formed on an outer side surface of the actuating member  48 . A finger recess  49  is provided so that when a user grasps the main body  2  together with this actuating member  48 , the user&#39;s fingers easily engage with the recess  49 .  
      2) The groove forming member  43  is fixed to the actuating member  48 , and the groove forming member  43  and the locking plate  16   a  are connected to each other through the wire  28  of the wire-type transmitting mechanism  27 .  
      3) Further, a biasing member  47  comprising a compression coil spring is interposed between a spring seat  46  formed on the first portion  2   a  of the main body  2  and the groove forming member  43 .The biasing member  47  biases the actuating member  48  through the groove forming member  43  into a posture corresponding to the locked state (to the upper position in  FIG. 17B ).  
      According to this embodiment, when a user performs a series of actions of pulling the main body  2  together with the actuating member  48  downwardly (in the axial direction W) with grasping those in an emergency, the hand and the actuating member  48  slide along the main body  2  and the locking plate  16   a  is displaced through the wire  28 , so that the lock is released. Therefore, the lock is easily and surely released.  
       FIGS. 18 and 19  show a further another embodiment of the present invention. Referring to  FIGS. 18 and 19 , this embodiment is different from the embodiment of  FIG. 11  mainly in the following points 1) to 4).  
      1) In the embodiment of  FIG. 11 , the pair of second portions  31  is provided as the actuating member displaceable in the radial direction of the main body  2 . However, in this embodiment, only one second portion  50  is provided as the actuating member displaceable in the radial direction of the main body  2  (radially displacing member). The second portion  50  is provided on half the periphery of the main body  2 . On an outer surface of the second portion  50 , a plurality of projections  51  is distributed for preventing a user&#39;s hand from slipping when the user grasps the second portion  50  together with the first portion  2   a  of the main body  2 .  
      2) In the embodiment of  FIG. 11 , the pair of locking plate  16   a ,  16   b  is used. However, in this embodiment, only one locking plate  16   a  is used, and this locking plate  16   a  and the second portion  50  are integrally formed of a single member.  
      3) In the embodiment of  FIG. 11 , the pin  13  is covered with the cover  35  formed integrally with the pin  3 . However, in this embodiment, the pin  3  protrudes above the main body  2 . AS shown in  FIG. 19 , on a circumferential surface of a longitudinal midway portion of the pin  3 , an annular resilient member  52  such as an O-ring is fitted for providing friction to the pin  3  when a user releases the pin  3 . The resilient member  52  is held by an annular groove formed on the first portion  2   a  of the main body  2 .  
      4) As a guide structure for guiding the second portion  50  as the actuating member so as to be displaced in the radial direction Y of the main body  2 , a guide projection  53  is provided on the first portion  2   a  of the main body  2 . And the guide projection  53  is fitted into a groove  54  formed on the second portion  50 . Further, a rib  55  is formed on a back surface of the second portion  50 , and a pair of biasing members  33  protruding from the containing hole of the first portion  2   a  biases the second portion  50  outwardly in the radial direction Y through the rib  55 .  
      In this embodiment, similar effects to those of the embodiment of  FIG. 11  can be also obtained. Further, since the only one second portion  50  as the actuating member is provided, the structure of the device is simplified and the reliability of the operation becomes higher.  
      In the present invention, the structure for interlocking the actuating member and the locking member is not limited to such a structure of mechanical transmission using a wire-type transmitting mechanism as used in each of the embodiments of  FIGS. 9, 15 , and  17 , but it may be one using an electric signal for interlocking. For example, as shown in the pattern view of  FIG. 20 , the lock may be released by applying a driving voltage from a driving circuit  61  to a solenoid  62  on the basis of a trigger signal obtained by displacement of the actuating member in the radial or axial direction of the main body and thereby releasing a locking member  63  connected to the solenoid  62  from an engaging groove  64 . Further, in each of the embodiments of  FIGS. 9, 15  and  17 , a biasing member for directly biasing the locking plate  16   a  to the locked position may be provided.  
      The present invention has been described by way of the concrete embodiments as above, and those skilled in the art who have understood the abovementioned description will be easily able to think of the variations, modifications and equivalents thereof. Therefore, the present invention should be limited by the scope of appended claims and their equivalents.