JP2012202167A - Lock device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reliably lock a movable body in a stop position.SOLUTION: When a door panel is moved toward a stop position, a steel plate 8 is moved. When the door panel reaches the stop position, a magnet lock 18 is positioned close to the steel plate 8. When the door panel reaches the stop position, the steel plate 8 is attracted by the magnet lock 18 while compressing a door closing spring 16, and the compressed door closing spring 16 pushes the door panel to the side of the magnet lock 18.

Description

  The present invention relates to a locking device that fixes and maintains a stopped state when a moving body that has moved has stopped, and, for example, relates to a technique for fixing an opening / closing body in a state where the opening / closing body of the opening / closing device is closed.

  The locking device as described above is, for example, an automatic door device whose opening / closing body is opened / closed by a driving device, a door device including a manual door device whose opening / closing body is manually opened / closed, or a train or vehicle provided on a platform of a station. It is sometimes used in platform safety fences and platform door devices that close the opening and closing until the train or vehicle door opens. A door device, for example, an automatic door device, takes a closed state in which an opening / closing body such as a door panel closes an opening such as a door opening. A locking device may be used to fix the door panel in this closed state. An example of the locking device is disclosed in Patent Document 1.

  In this lock device, a movable suction portion made of a ferromagnetic material is provided on the door panel so as to move together with the door panel, and a permanent magnet is provided in the vicinity of the position where the movable suction portion reaches when the door panel reaches the closed position. A stationary suction part is arranged. When the door panel reaches the closed position, the permanent magnet of the stationary suction part attracts and holds the movable suction part in the direction of closing the door panel.

Japanese Patent No. 4147104

  According to the above technique, when the stop position of the moving body is shifted due to, for example, aging of the door device or the like, the door panel cannot be reliably locked at the stop position.

  An object of this invention is to provide the locking device which can lock a mobile body reliably in a stop position.

  The locking device according to one aspect of the present invention includes: a first magnetic force holding unit that moves as the moving body moves toward a predetermined stop position; and when the moving body reaches the stop position, A second magnetic force holding means fixed so as to be located close to the first magnetic force holding means. Examples of the moving body include a door panel of a door device as described above, a moving fence of a safety fence of a station platform, a door panel of a platform door device, a rod of a cylinder device, and the like. One of the first and second magnetic force holding means is constituted by a magnetic force generating means, and the other is constituted by a magnetically attracted means attracted and held by magnetic force. That is, the first magnetic force holding means is constituted by a magnetic force generating means, the second magnetic force holding means is constituted by a magnetic attracted means, and the first magnetic force retaining means is constituted by a magnetic attracted means, and the second magnetic force retained. In some cases, the means is constituted by a magnetic force generating means. As the magnetic force generation means, the surface of the magnetic force generation means is continuously magnetized when the current of the first polarity is supplied unsustainably, and the second polarity of the magnetic force generation means is non-sustainably applied in this magnetization state. An electromagnet that is configured to be continuously demagnetized when current is supplied, or that is magnetized when a predetermined current is supplied and demagnetized when current supply is stopped It is possible to use a neutralization type that demagnetizes by arranging a coil around a permanent magnet, generating an attractive force by the magnet when the current supply is stopped, and supplying the current. Magnetic devices can also be used. As the magnetically attracted means, a ferromagnetic material magnetized by a magnetic force can be used. Also, a pressing means for elastically pressing the moving body toward the first magnetic force holding means is provided.

  If comprised in this way, when the stop precision of the repetition of a moving body is low, for example, the approach stop distance of a 1st and 2nd magnetic force holding means is not stable, or the apparatus to which a moving body is attached, for example, a building or a door apparatus Even when the moving body stops at a position slightly before the stop position due to deterioration over time, etc., if the first and second magnetic force holding means are attracted and attracted by the magnetic force, the pressing means The moving body is stopped at the stop position by pressing toward the first magnetic force holding means.

  In the locked state, when the moving body is moved in a direction opposite to the moving direction with a force equal to or greater than the pressing force by the pressing means, the movement inhibition that prevents the first magnetic force holding means from moving in the direction opposite to the moving direction. Means can also be provided. For example, when the first magnetic force holding means is constituted by a magnetically attracted means that is a ferromagnetic plate that is magnetized by a magnetic force, one end of the movement preventing means is fixed to the magnetically attracted means, The plate-like part provided in the moving body can be penetrated, and the enormous part that can contact the plate-like part provided in the moving body can be provided at the other end of the movement preventing means. In this case, the pressing means is disposed between the plate-like portion of the moving body and the enormous portion of the movement-preventing means, and an elastic body that is compressed when the plate-like portion of the moving body and the first magnetic force holding means are separated. Can be used.

  With this configuration, an external force is applied so that the moving body moves, for example, in the direction opposite to the moving direction of the moving body at the stop position, and even if the external force is larger than the pressing force of the pressing means, the movement is prevented. Means prevent further movement. When the external force is removed, the moving body returns to the stop position again by the pressing force of the pressing means. As a result, even if something is pinched when the moving body stops at the stop position, the moving body can be automatically stopped again at the stop position after removing the object.

  As described above, according to the present invention, the moving body can be reliably stopped at the stop position even when the stopping accuracy of the moving body is low.

It is a partial fracture top view of the locking device of one embodiment of the present invention. It is operation | movement explanatory drawing of the magnet lock of the locking device of FIG. It is sectional drawing which follows the AA line of FIG. It is a right view of the locking device of FIG. It is sectional drawing which follows the BB line of FIG. It is a figure which shows a part of process in which a door panel approaches a stop position and is locked by the locking device of FIG. It is a figure which shows the remaining part of the process in which a door panel approaches a stop position and is locked by the locking device of FIG. It is operation | movement explanatory drawing of the cancellation | release lever of the locking device of FIG.

  A locking device according to an embodiment of the present invention is an automatic door device implemented by the present invention. This automatic door device is, for example, of a double-open or single-sliding slide door type, and an opening, for example, a movable body arranged on both sides or one side of the door opening, for example, a door panel, slides to open and close the door opening. The locking device of this embodiment is provided to lock the door panel when the door panel reaches a stop position, for example, a closed position where the door panel closes the door opening.

  For example, as shown in FIG. 1, the door panel has a door roller 2 that slides together with the door panel in the interior of an automatic door device. The center axis of the door roller 2 is arranged in an invisible depth direction, and the outer peripheral surface of the door roller 2 is in contact with an invisible guide rail (not shown). The door panel moves in the direction of the arrow when moving from the open position to the closed position, and in the left direction in FIG. 1, and moves in the direction opposite to the arrow when sliding from the closed position to the open position, and to the right in FIG. The door roller 2 is attached to a mounting bracket 4. When the door panel slides toward the closed position, as shown by an arrow in FIG. 1, in FIG. 1, the automatic door device slides to the left side, and the door panel slides from the closed position to the open position. Sometimes it slides to the right in FIG. A mounting bracket 6 is attached to the mounting bracket 4. This mounting bracket 6 has a horizontal portion 6a attached to the mounting bracket 4, and is formed at the tip of the door panel on the sliding direction side so as to form an acute angle with respect to the horizontal portion 6a, for example, slightly smaller than 90 degrees. It has the acute angle part 6b made. The mounting bracket 6 is made of metal, for example.

  A first magnetic force holding means, for example, a magnetically attracted means, specifically a ferromagnetic plate, more specifically a steel plate 8 is attached to the surface of the acute angle portion 6b opposite to the door roller 2. The steel plate 8 is formed in a flat plate shape, and one end, for example, the other end of the lower end of FIG. 1, for example, the upper end of FIG. 1, is inclined toward the door roller 2 side, for example, an acute angle portion substantially parallel to the acute angle portion 6b. It is attached to 6b. This attachment is performed by the guide pin 12 and the movement preventing means, for example, the lock pin 14 through the O-rings 10 and 10.

  The guide pins 12 and the lock pins 14 are arranged at intervals in the vertical direction in FIG. One end of the guide pin 12 is fixed to the steel plate 8, and the other end is orthogonal to the acute angle portion 6 b, passes through the guide hole 13, and protrudes toward the door roller 2. Therefore, the steel plate 8 is movable along the length direction of the guide pin 12. One end of the lock pin 14 is also fixed to the steel plate 8, penetrates the acute angle portion 6b orthogonally, and protrudes to the door roller 2 side. The protruding portion is formed in a huge portion 14 a that is larger than the portion penetrating the steel plate 8. A door closing spring 16 made of a pressing means, for example, a coil spring, is attached between the enormous portion 14a of the lock pin 14 and the surface of the acute angle portion 6b on the door roller 2 side. For example, when the door panel is in the closed position and the steel plate 8 is locked by magnetic force as will be described later, an external force is applied to the door panel in the direction to open the door panel, and the door panel is moved in the direction opposite to the arrow in FIG. When the external force is greater than the pressing force of the door closing spring 16, the door roller 2 and the mounting bracket 4 move slightly in the direction opposite to the arrow, but the sharp angle portion 6b contacts the enormous portion of the lock pin 14 and the further The movement is blocked, i.e. locked.

  When the door panel stops near the closed position, second magnetic force holding means, for example, magnetic force generating means, specifically, a magnet lock 18 is attached near the position where the steel plate 8 is disposed.

  As shown in FIG. 2A, the magnet lock 18 has a main body portion 20. The main body 20 is made of a ferromagnetic material such as steel, and is provided with U-shaped members 20a and 20b having a U-shaped longitudinal section so as to form an angle of 90 degrees with each other. The main body 20 has a second contact surface, for example, a suction surface 22. As shown in FIG. 1, the suction surface 22 faces a first contact surface of the steel plate 8, for example, a suction surface 24 located on the opposite side of the door roller 2, and the suction surface 24 is opposed to the suction surface 22. Inclined. The main body 20 has a housing portion 26. The accommodating portion 26 is a space surrounded by the U-shaped members 20 a and 20 b, opens at the suction surface 22, and extends from the suction surface 22 toward the inside of the main body portion 20. As shown in FIG. 1, the main body 20 is fixed to a fixing portion 28 provided in a seamless manner via bolts (not shown).

  A magnet whose polarity can be switched, for example, an alnico magnet 30 is disposed in the interior of the housing portion 26 as shown in FIGS. 2 (a) and 2 (b). The alnico magnet 30 is formed in a rectangular parallelepiped shape, for example, and the surface on the suction surface 22 side is located behind the suction surface 22. A polarity switching coil 32 is provided on the outer periphery of the alnico magnet 30. The polarity switching coil 32 is attached to the alnico magnet 30 so as to surround its outer peripheral surface. When a first polarity current, for example, a positive current is passed through the polarity switching coil 32 in a non-persistent manner, the polarity of the alnico magnet 30 is converted, and the converted state is maintained. In addition, if a current having a second polarity opposite to the first polarity, for example, a negative current is caused to flow non-persistently in the polarity switching coil 32 in a state where the polarity is converted, the polarity of the alnico magnet 30 is restored to the original polarity. Return to polarity and maintain the returned polarity.

  Before the positive current is supplied, for example, as shown in FIG. 2A, the alnico magnet 30 is arranged so that the south pole faces the suction surface 22 side and the north pole faces the inner part of the housing portion 26. ing. After the positive current is supplied unsustainably, the N pole of the alnico magnet 30 faces the attracting surface 22 side, and the S pole faces the inner part of the housing portion 26 as shown in FIG.

  A magnet block 34 made of a ferromagnetic material, for example, steel, is disposed in contact with the alnico magnet 30 so as to fill the center of the space between the surface on the attraction surface 22 side of the alnico magnet 30 and the attraction surface 22. The magnet block 34 is also in the shape of a rectangular parallelepiped, and is fixed to the main body 20 together with the alnico magnet 30 by a bolt (not shown).

  In the gap between the magnet block 34 and the inner wall surface of the accommodating portion 26, a plurality of, in this embodiment, six permanent magnets, for example, neodymium magnets 36 surround the outer periphery of the magnet block 34 as shown in FIG. Are arranged as follows. These neodymium magnets 36 also have a rectangular parallelepiped shape, and in a state before a positive current is supplied to the switching coil 32, the polarity N opposite to the magnetic pole S on the attracting surface 22 side of the alnico magnet 30 faces the magnet block 34 side. As shown, all the neodymium magnets 36 are arranged.

  Since it is configured in this way, before supplying a positive current, a magnetic closed loop is configured by the alnico magnet 30, the magnet block 34, the neodymium magnet 36, and the main body 20 as shown in FIG. Magnetic force does not come out of the magnet block and is not attracted even if the steel plate 8 is on the attracting surface 22 side of the magnet block 34. This state is called a demagnetized state.

  When a positive current is supplied non-continuously to the polarity switching coil 32, the polarity of the alnico magnet 30 is N on the attracting surface 22 side and S on the inner back side, as shown in FIG. A magnetic closed loop is formed by the block 34 and the main body 20, and the magnetic closed loop passes from the magnet block 34 to the outside of the attracting surface 22. Therefore, when the steel plate 8 is located outside, it is attracted to the magnet lock 18. In this state, if a positive current is supplied again unsustainably, the generated magnetic force can be increased. The state in which a positive current is first supplied non-sustainably to generate a magnetic force is referred to as a pre-magnetization state, and the second state in which a positive current is supplied non-persistently to increase the magnetic force is normally magnetized. It is called a state.

  As shown in FIG. 3, sound absorbing materials, for example, rubber cushion portions 38 a and 38 b are attached to the four corners of the magnet block 34. These rubber cushion portions 38a and 38b are formed in a columnar shape as shown in FIG. The rubber cushion portion 38a on the upper end side in FIG. 1 of the steel plate 8 has a larger protruding amount than the rubber cushion portion 38b on the lower end side in FIG. 1, and its repulsive force is larger than that on the lower rubber cushion 38b. .

  Hereinafter, the operation of the locking device will be described with reference to FIGS. 6 and 7. 2A, the magnet lock 18 is in a demagnetized state, the door panel is in the open position, and the steel plate 8 and the door roller 2 are separated from the magnet lock 18 as shown in FIG. Suppose you are at a distance. In this state, the door panel moves toward the closed position as shown in FIG. At this time, the magnet lock 18 is in the pre-magnetization state described above. The magnet lock 18 can be set in the pre-magnetized state before the door panel reaches the closed position as described above, or after reaching the vicinity of the closed position.

  Eventually, the door panel moves to the closed position, and the steel plate 8 approaches the magnet lock 18 as shown in FIG. At this time, the magnetic force that is still generated by the magnet lock 18 is not so large that it has entered the steel plate 8, and the steel plate 8 is not yet attracted.

  When the door panel is very close to the door stop position, the lower end of the steel plate 8 is bent and adsorbed by the magnetic force of the magnet lock 18 as shown in FIG. At this time, the guide pin 12 and the lock pin 14 also move slightly toward the magnet lock 18 as the lower end of the steel plate 8 is attracted. The upper end side of the steel plate 8 has a large repulsive force of the rubber cushion 38 a and is separated from the magnet block 18, so that the magnetic force passing through the inside is small and is not attracted to the magnet lock 18.

  Since the door panel is controlled to decelerate when approaching the closed position, the moving speed of the steel plate 8 is slow, and when the lower end of the steel plate 8 is attracted to the magnet lock 18, the rubber cushion 38b is bent, and at this time (when the lower end of the steel plate 8 is attracted to the magnet lock 18), a sound is generated when the door panel reaches the closed position and stops. The sound generated when the lower end is adsorbed is difficult to notice.

  In this state, when the normal magnetization state is set and the magnetic force is increased, the upper end of the steel plate 8 is attracted to the magnet lock 18 as shown in FIG. That is, the steel plate 8 is sucked and held in the complete suction state. At this time, the steel plate 8 is adsorbed together with the guide pins 12 while bending the door closing spring 16. When the steel plate 8 is attracted, the guide pin 12 moves so as to slide along the guide hole 13 so that the attracting surface 24 on the upper end side of the steel plate 8 also moves so as to slide on the attracting surface 22 of the magnet lock 18 and is attracted. The In this way, the lower end of the steel plate 8 is attracted to the magnet lock 18, and then the upper end side attracting surface 24 is attracted to the magnet block 18 so as to slide on the attracting surface 22 of the magnet lock 18. Almost no sound is generated when it is played. Further, since the bent door closing spring 16 presses the acute angle portion 6b toward the magnet lock 18, the door panel is further fixed.

  Since the door panel can be locked at the stop position in this manner, it is not necessary to press the door panel against the door opening side by the motor to maintain the closed state of the door panel. Therefore, after the door panel is moved to the vicinity of the closed position, it is not necessary to supply current to the motor, and power saving can be achieved. Further, since the door panel can be locked by supplying current to the magnet lock 18 in a non-persistent manner, it is not necessary to supply the current to the magnet lock 18 to maintain the door lock, which also saves power. Can be achieved.

  When the external force is applied in the opposite direction to the closing direction of the door panel as shown by the arrow in FIG. 5B in this complete adsorption state, the door panel is moved to the arrow if the external force is smaller than the spring force of the door closing spring 16. However, if the external force is larger than the spring force of the door closing spring 16, the mounting brackets 6, 4 and the door roller 2 move in the direction of the arrow while the door closing spring 16 is contracted. The acute angle portion 6b contacts the enormous portion 14a of the lock pin 14, and further movement is prevented. When the steel plate 8 is attracted to the magnet lock 18, the door panel moves in the opening direction, and the final locking force depends on the attracting force between the magnet lock 18 and the steel plate 8.

  When the door panel is moved in an opening direction with an external force larger than the spring force of the door closing spring 16, the door panel can move until the acute angle portion 6 b contacts the enormous portion 14 a of the lock pin 14. In the case of a device, the clothes can be removed even when clothes or the like are sandwiched between the door panels, and in the case of a single sliding door device, between the door panel and the edge of the door opening. When the external force is removed, the mounting brackets 4 and 6 and the door roller 2 are returned to their original positions by the spring force of the door closing spring 16 as shown in FIG. Locked.

  In the above description, the case where the door panel is stopped at the stop position has been described. However, when the accuracy of stopping the door panel repeatedly is low and the approach stop distance between the steel plate 8 and the magnet lock 18 is not stable, Even if the door panel stops at a position slightly before the stop position due to aging of the attached building or automatic door device, the steel plate 8 is sucked and held by the magnetic lock 18, and the steel plate is then steeled as described above. Since the plate 8 is bending the door closing spring 16, the acute angle portion 6 b is moved to the magnet lock 18 side by the spring force, so that the door panel is also connected via the horizontal portion 6 a, the mounting bracket 4, and the door roller 2. It is moved to the magnet lock 18 side, moved to a predetermined stop position, and locked.

  In order to detect that the steel plate 8 has been attracted and held as described above, as shown in FIG. 1, a detection switch 40 is provided on the side of the magnet lock 18, and as shown in FIG. On the side of 8, a switch operation unit 42 is formed integrally therewith. The switch operation unit 42 contacts the detection switch 40 in a state where the steel plate 8 is displaced and held by suction, and operates this to notify that the suction is held.

  When a negative current is supplied to the polarity switching coil 32 in a non-sustained state in the attraction holding state, the magnetic pole on the attraction surface 22 side of the alnico magnet 30 is set to the S pole, as shown in FIG. The magnetic pole on the back side becomes the N pole, so that the magnetic force does not pass through the steel plate 8 as described above, a magnetic closed loop is formed in the magnet lock 18, and the suction and holding of the steel plate 8 is released. Therefore, if a negative current is supplied to the polarity switching coil 32 in a non-persistent manner before the door panel is moved, the demagnetization state occurs and the door panel becomes movable.

  If a power failure occurs in the state where the magnet lock 18 is used to suck and hold the door panel, the door panel remains sucked and held, and a person cannot go outside the automatic door device. Therefore, as shown in FIGS. 8A and 8B, a suction release lever 44 is provided on the upper surface of the magnet lock 18. The suction release lever 44 is attached to be rotatable around a rotation shaft 46 provided on the upper surface of the magnet lock 18 in FIG. The suction release lever 44 has an operation edge 48 on the steel plate 8 side. When the suction release lever 44 is rotated around the rotation shaft 46 in the direction indicated by the arrow in FIG. The edge 48 comes into contact with the steel plate 8, and the steel plate 8 is pulled away from the magnet lock 18 as shown in FIG. The suction release lever 44 can be operated from the outside without eyes. As a result of releasing the suction and holding of the door panel, the door panel can be moved to the open position by, for example, manual operation by a person, and the person can go outside from the automatic door device at the time of power failure.

  A stopper 50 is provided on the upper surface of the magnet lock 18 in order to restrict the rotation angle of the suction release lever 44 within a predetermined angle. As shown in FIG. 4B, when the suction release lever 44 rotates by a predetermined angle, the inner edge 52 of the suction release lever 44 comes into contact with the stopper 50 to prevent further rotation. In this state, in order to automatically return the suction release lever 44 to the original position, a return torsion coil spring 54 is inserted around the rotation shaft 46, and one end thereof is provided on the upper surface of the magnet lock 18. The other end is in contact with the pin 56 and the other end is in contact with the pin 58 provided on the lower surface of the suction release lever 44. When a force is applied to the suction release lever 44 in order to rotate the suction release lever 44 as indicated by an arrow in FIG. 5A, the return torsion coil spring 54 is twisted and the force is removed from the suction release lever 44. Then, when the twisted spring 54 returns to the original state, the suction release lever 44 is rotated to the original position shown in FIG.

  In the above-described embodiment, the alnico magnet 30 and the magnet block 34 have a rectangular parallelepiped shape. However, the present invention is not limited to this, and for example, a cylindrical shape can be used. In this case, the neodymium magnet 36 is annularly disposed around the magnet block 34. In the above embodiment, the rubber cushion portions 38 a and 38 b are cylindrical ones arranged at the four corners of the neodymium magnet 36. However, the present invention is not limited to this, and the rubber cushion portions 38 a and 38 b may be provided annularly along the neodymium magnet 36. Further, a dedicated hole can be formed in the main body portion 20 and provided in this hole. Similarly, it can be provided on the steel plate 8 side.

  In the above embodiment, the steel plate 8 is moved together with the door panel and fixed to the magnet lock 18, but conversely, the steel plate 8 may be fixed and the magnet lock 18 may be moved together with the door panel.

  In the above embodiment, the locking device of the present invention is used to hold this closed state when the door panel reaches the closed position, but this open state is held when the door panel reaches the open position. The present invention can also be used for this purpose. It can also be used to lock a door panel when a building or store where a sliding automatic door device is installed is closed at midnight or the like. In the above embodiment, the present invention is applied to an automatic door device. However, the present invention is not limited to this, and the present invention can be applied to a door device that manually opens and closes a door panel. The present invention can also be implemented in safety fences and platform door devices that are arranged. It can also be used when locking with the rod of an air cylinder or hydraulic cylinder extended.

  In the above embodiment, the neodymium magnet 36 is attached so that its N pole faces the magnet block 34 side, but it can also be attached so that its S pole faces the magnet block 34 side. However, in that case, the Alnico magnet 30 is arranged so that the N pole faces the attracting surface 22 side and the S pole is located in the inner part of the housing portion 26 before the positive current is supplied. In the above embodiment, the steel plate 8 is sucked and held when a positive current is supplied non-persistently, and the steel plate 8 is released from the suction hold when a negative current is supplied non-persistently. The steel plate 8 was sucked and held when a negative current was supplied non-sustainably by changing the winding direction of the polarity switching coil 32, and a positive current was supplied non-persistently. In some cases, the steel plate 8 may be opened.

  In the above embodiment, the steel plate 8 is provided in a state where the upper end of the steel plate 8 is inclined toward the door roller 2, but the steel plate 8 is disposed so that the attracted surface 24 thereof is parallel to the attracting surface 22 of the magnet lock 18. In addition, although the mounting bracket 6 is shown in which the acute angle portion 6b forms an acute angle with respect to the horizontal portion 6a, the acute angle portion 6b is a right angle portion or an obtuse angle forming a right angle or an obtuse angle with respect to the horizontal portion 6a. It can also be a part.

8 Steel plate (first magnetic force retaining means, magnetic force attracting means)
14 Lock pin (movement blocking means)
16 Door closing spring (pressing means)
18 Magnet lock (second magnetic force holding means, magnetic force generating means)

Claims (2)

First magnetic force holding means that moves as the moving body moves toward a predetermined stop position;
A second magnetic force holding means fixed so as to be positioned close to the first magnetic force holding means when the moving body reaches the stop position;
And one of the first and second magnetic force holding means is constituted by a magnetic force generating means, and the other is constituted by a magnetically attracted means that is attracted and held by magnetic force,
A locking device provided with pressing means for elastically pressing the movable body toward the first magnetic force holding means. The locking device according to claim 1, wherein when the moving body is moved in a direction opposite to the moving direction by a force equal to or greater than a pressing force by the pressing means, the first magnetic force holding means is moved in a direction opposite to the moving direction. A locking device having movement blocking means for blocking movement.

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