JP3913050B2 - Fall prevention device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fall prevention device that prevents a displacement body that moves up and down and is held at a preset holding position from falling from the holding position.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in order to secure a parking space for an automobile, a three-dimensional parking machine that raises and lowers a pallet on which an automobile is placed by a chain driven by a motor has been put into practical use. In such a multilevel parking machine, when holding the pallet in the raised position, the pallet is usually held by a chain, but in order to prevent the pallet from falling even if this chain breaks The fall prevention device is installed.
[0003]
And this kind of fall prevention device is provided with a lever that can be taken in and out of the lifting path of the pallet, and prevents the pallet from falling by projecting the lever into the lifting path of the pallet, and the lever from the lifting path of the pallet. By evacuating, the pallet is not hindered.
[0004]
As a drive mechanism for projecting / retracting such a lever, generally, a movable iron core is connected to a lever pivotally supported by a rod via a rod, and the electromagnetic solenoid is energized. In this case, the lever is driven by sucking the movable iron core.
[0005]
[Problems to be solved by the invention]
However, in such a fall prevention device using an electrically operated drive mechanism, it is necessary to provide a power source for driving or to perform wiring, and further, it is necessary to take measures against electric leakage against rainwater, etc. However, there has been a problem that the assembly work of the multilevel parking garage and the adjustment and maintenance work after the assembly are time-consuming.
[0006]
In order to solve the above problems, an object of the present invention is to provide a fall prevention device that can be easily assembled and maintained and can be manufactured and operated at low cost.
[0007]
[Means for Solving the Problems]
  The invention according to claim 1, which has been made to achieve the above object, is a fall prevention device that moves up and down and prevents a displacement body held at a preset holding position from falling from the holding position. The displacement body is configured to be movable between a protruding position protruding from the lifting path and a retracted position retracted from the lifting path, and at the protruding position, passage of the displacement body descending from the holding position is prevented. In addition, the displacement body is brought into direct or indirect contact with the displacement body that rises toward the holding position and moves toward the retracted position as the displacement body rises. A movable member that automatically returns to the protruding position when the contact with is released, and that cannot automatically return to the protruding position at the retracted position;Covering the front wall of the housing in which the opening for inserting and removing the movable member is formed, and attached to the housing so as to be movable in the ascending / descending direction of the displacement body along the front wall, the opening And a guide plate in which a notch is formed in a portion facing the surface, and projecting from the upper portion of the guide plate toward the lifting path of the displacement body,When the displacement body is in the operation region set above the holding position, the displacement body is interlocked with the displacement body.The guide plateMove up and downThe guide plateAt the rise ofThe lower end of the notch isThe movable memberLower edge ofAn interlocking mechanism for moving the movable member to the retracted position in contact with the movable member, and when the movable member is in the retracted position, the movable member is in contact with and displaced by the displacement body descending beyond the installation position of the movable member, And a first return operation mechanism for moving the movable member from the retracted position to a position where at least the automatic return to the protruding position is possible.
[0008]
In the fall prevention device of the present invention configured as described above, no special operation is required when the displacement body is raised to the holding position, and if the displacement body is simply raised, it directly or indirectly contacts the displacement body. The movable member thus moved moves to the retracted position side as the displacement body rises, so that the displacement body passes through the installation position of the movable member and reaches the holding position. In addition, the movable member that has passed through the displacement body and released from contact with the displacement body automatically returns to the protruding position. This prevents the displacement body held at the holding position from falling.
[0009]
  Next, when the displacement body is lowered from the holding position, the movable member at the projecting position gets in the way, so the displacement body is first raised to the operating region set above the holding position. Then, in this operating area,Operation plateIn conjunction with the displacement bodyGuide plateLifting movementLet the guide plateWhen rising, The lower end of the notchMovable memberLower edge ofThe movable member is moved to a retracted position where automatic return to the protruding position is impossible.
[0010]
As a result, the displacement body can pass through the installation position of the movable member. Therefore, when the displacement body is lowered, the first return operation mechanism comes into contact with the displacement body that descends beyond the installation position of the movable member. Then, the movable member is moved from the retracted position to a position where automatic return to at least the protruding position is possible. That is, after the displacement body passes, the movable member returns from the retracted position to the protruding position.
[0011]
Thus, according to the fall prevention device of the present invention, since the movable member is driven by the vertical movement of the displacement body without using the electromagnetic solenoid, it is necessary to provide a dedicated power source for driving the movable member. In addition, since it is not necessary to take measures against electric leakage due to rainwater or the like, the apparatus configuration can be simplified and can be manufactured at low cost.
[0012]
In addition, since the fall prevention device of the present invention does not require wiring and does not require replacement of electric parts, it is easy to install / adjust and maintain in a multi-story parking lot, etc. Since there is no consumption, it can be operated at low cost.
Furthermore, according to the fall prevention device of the present invention, since the driving force based on the vertical movement of the displacement body is strong, even when the movement of the movable member becomes worse due to rust, freezing, etc., this is forcibly operated. As a result, rust and freezing can fall off and can automatically return to a good operating state.
[0013]
In addition, the interlocking mechanism that transmits the movement of the displacement body to the movable member moves up and down with the displacement body and moves the movable member by contacting the movable member. It is difficult and high reliability can be obtained.
Note that the movable member that has been moved to the retracted position by the retracting operation mechanism may be configured such that the restraining means restrains the retracted position as described in claim 2. In this case, if there is no restraining means, the retracted position can be set at a position where the movable member automatically returns to the protruding position due to its own weight. That is, as long as the restraint by the restraining means is released, the movable member returns to the protruding position, so that the displacement width of the movable member by the first return operation mechanism can be reduced, and the apparatus can be downsized.
[0014]
  Further, when such a restraining means is provided, the biasing means may bias the movable member toward the protruding position as described in claim 3. In this case, the movable member at a position other than the retracted position can be surely automatically returned to the protruding position, and the operation reliability can be improved.
  As described in claim 4, a roller may be provided at the lower end of the notch.
[0015]
  Next, the claim5The invention described is a fall prevention device for preventing a displacement body that moves up and down and that is held at a preset holding position from falling from the holding position, and that protrudes into the lifting path of the displacement body. A displacement that is movable between a position and a retracted position that is retracted from the lifting path, and that prevents the displacement body that descends from the holding position from passing through and moves upward toward the holding position at the protruding position. Directly or indirectly contacting the body, moving to the retracted position side as the displacement body rises, passing the displacement body, and releasing the contact with the displacement body, the protruding position And a movable member that cannot be automatically returned to the protruding position at the retracted position, and is provided integrally with the movable member, and is located above the holding position when the movable member is at the protruding position. Elevating the displacement body A retracting operation member that protrudes into the path and displaces when it contacts the displacement body to move the movable member to the retracted position, and when the movable member is at the retracted position, the movable member descends beyond the installation position of the movable member. A first return operation mechanism that moves in contact with the displacement body and moves the movable member from the retracted position to at least a position where automatic return to the protruding position is possible;The first return operation mechanism is provided integrally with the movable member. When the movable member is in the retracted position, the first return operation mechanism protrudes into a lifting path of the displacement body at a lower portion of the movable member and contacts the descending displacement body. A return motion member that displaces
The return operation member and the retraction operation member are formed of a single member.It is characterized by that.
[0016]
In other words, in the fall prevention device of the present invention, instead of the interlocking mechanism according to claim 1, a retraction operation member provided integrally with the movable member is provided, and the retraction operation member has the movable member in the protruding position. Sometimes it protrudes into the lifting path of the displacement body above the holding position. For this reason, when the displacement body in the holding position is raised and brought into contact with the retracting member, the retracting operation member is displaced, so that the movable member provided integrally therewith is retracted as in the case of the interlocking mechanism. Move to position.
[0017]
Therefore, according to the fall prevention device of the present invention, the same effect as the fall prevention device according to claim 1 can be obtained. In particular, in the present invention, since the retracting operation member is provided integrally with the movable member, the apparatus configuration becomes simpler.
The first return mechanism is, for example, provided integrally with the movable member. When the movable member is in the retracted position, the first return operation mechanism protrudes into the ascending / descending path of the displacement body at the lower portion of the movable member, and moves downward. When it consists of a return motion member that contacts and displaces, the retracting motion member and the return motion member that are formed separately may be attached to the movable member to be integrated with the movable member. Alternatively, as described in claim 5, the return operation member and the retraction operation member may be constituted by a single member.
[0018]
In this case, it is possible to reduce the work of integrating the return operation member and the retraction operation member with the movable member.
The movable member that has been moved to the retracted position by the interlocking mechanism may be configured such that the restraining means restrains the retracted position as described in claim 6. When such a restraining means is provided, the biasing means may bias the movable member toward the protruding position as described in claim 7. In these cases, the same effects as those of the fall prevention device according to claims 2 and 3 can be obtained.
[0019]
By the way, in the fall prevention device that mechanically operates the movable member in this way, when there are a plurality of displacement body holding positions, the displacement body exceeds the first holding position and reaches the next holding position set on the upper part thereof. When moving, the retraction operation mechanism of the fall prevention device installed at the first holding position is activated. Then, since the movable member remains held in the retracted position, even if the new displacement body is raised to the initial holding position, not only the movable member cannot be moved to the protruding position, but in some cases, There is a possibility that the first return operation mechanism may be in the way and cannot even be raised to the initial holding position.
[0020]
Accordingly, the invention described in claim 8 is a fall prevention device for preventing a displacement body that moves up and down and is held at a preset holding position from falling from the holding position, and is provided with a lifting path of the displacement body. It is configured to be movable between a protruding position protruding to the retracted position retracted from the ascending / descending path, and at the protruding position, the passage of the displacement body descending from the holding position is blocked and directed toward the holding position. Directly or indirectly abutting on the rising displacement body and moving to the retracted position side as the displacement body rises, allowing the displacement body to pass therethrough and releasing the contact with the displacement body. And a movable member that automatically returns to the protruding position and cannot automatically return to the protruding position at the retracted position, and a displacement body that rises beyond the holding position to displace the movable member. Move to the retracted position When the movable member is in the retracted position, the retracting operation mechanism is moved in contact with the displacement body that descends beyond the installation position of the movable member, and the movable member is moved from the retracted position to at least the protruding position. A first return operation mechanism that moves to a position where the automatic return can be performed, and a displacement body that rises beyond the operating region of the retraction operation mechanism to displace the movable member from the retraction position at least the protruding position And a second return operation mechanism that moves to a position where automatic return to the position is possible.
[0021]
In the fall prevention device of the present invention configured as described above, when the displacement body moves from the holding position to the second holding position that is further above, the second return operation mechanism exceeds the operating area of the retraction operation mechanism. Further, the movable member is displaced in contact with the ascending displacement body, and the movable member is moved from the retracted position to at least a position where automatic return to the protruding position is possible.
[0022]
In other words, when the displacement body moves to the second holding position, the second return operation mechanism returns the movable member that has moved to the retract position by the operation of the retraction operation mechanism to the protruding position. When it has moved up to the holding position, the movable member can be operated normally, and the displacement body newly held at the holding position can be prevented from falling.
[0023]
Specifically, the second return operation mechanism is pivotally supported, for example, as described in claim 9, and protrudes into the lifting path at the upper part of the operating region of the retraction operation mechanism, and It has an operating end that comes into contact with the movable member in the retracted position, and is configured by a link member that is displaced in a direction in which the operating end moves the movable member to the protruding position side due to the displacement of the protruding end caused by the contact of the displacement body. can do.
[0024]
Note that the movable member that has been moved to the retracted position by the retracting operation mechanism may be configured such that the restraining means restrains the retracted position as described in claim 10. When such a restraining means is provided, the biasing means may bias the movable member toward the protruding position as described in claim 11. In these cases, the same effects as those of the fall prevention device according to claims 2 and 3 can be obtained.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[First Embodiment]
Fig.2 (a) is a side view showing schematic structure of the two-stage type | mold multi-story parking machine with which the fall prevention apparatus of this embodiment was applied, FIG.2 (b) is the AA sectional drawing.
[0026]
As shown in FIG. 1, the multi-story parking machine 2 is configured so that a car can be parked in two upper and lower stages, and a pallet 4 for placing a car parked on the upper stage, and a pallet 4 are raised and lowered. The lifting mechanism 6 is held at the upper position or the lower position, the motor 8 drives the lifting mechanism 6, and the control device 10 controls the operations of the lifting mechanism 6, the motor 8, and the like.
[0027]
Among these, the elevating mechanism 6 is provided for each of the four columns P in total standing on the both sides along the longitudinal direction of the pallet 4 and each side along the longitudinal direction of the pallet 4. And two girders K fixed to each of the two columns P.
And the sprocket 12 is provided in the upper part of each support | pillar P, and the chain 14 which raises / lowers the pallet 4 is latched by each sprocket 12. As shown in FIG. Each sprocket 12 is attached to a common drive shaft 16, 17 for each of the sprockets 12 positioned at both ends in the longitudinal direction of the pallet 4, and one drive shaft 16 is directly rotated by a motor 8. The other drive shaft 17 is rotationally driven via a drive force transmitting sprocket 13 and a chain 15 attached to each drive shaft 16, 17.
[0028]
In addition, two drop prevention devices 20 according to the present embodiment, which prevent the pallet 4 from dropping when the pallet 4 is held at the raised holding position, are fixed to the lower portions of the girders K, respectively.
Here, FIG. 1 is a perspective view showing the appearance of the fall prevention device 20 of the present embodiment.
[0029]
As shown in FIG. 1, the fall prevention device 20 includes a mounting plate 21 in which a screw hole 21 a for fixing the device 20 to the girder K is formed, and is suspended from the mounting plate 21. A housing 22 integrated with the mounting plate 21 by welding; a cover 23 that covers the rear opening of the housing 22 and forms a rear wall; The lever 24 that is taken in and out from the opening 22a formed in the front wall, covers the front wall of the housing 22, and is movable along the front wall in the vertical direction in the figure (the pallet lifting direction). A guide plate 25 attached to the body 22 and having a notch 25a in a portion facing the opening 22a, an operation plate 26 projecting from the upper portion of the guide plate 25 toward the lifting path of the pallet 4, and a housing 22 protrudes from the lower part and operates integrally with the lever 24 And a return plate 27.
[0030]
Among these, for the attachment to the housing | casing 22, the attachment part is extended in the guide plate 25 along the both side walls of the housing | casing 22, and each attachment part is along the raising / lowering direction of a pallet. Long long holes 25b are respectively formed. And the guide plate 25 is attached to the housing | casing 22 in the state which can be moved to an up-down direction by fixing a pair of pin 28 which penetrated each long hole 25b to the side wall of the housing | casing 22. .
[0031]
When the guide plate 25 is at the lower end of the moving range, the notch 25a is formed to face the opening 22a of the housing 22, and the guide plate 25 is formed at the lower end of the notch 25a. A roller 29 is provided to abut the lower edge of the lever 24 and push the lever 24 into the opening 22 a of the housing 22 when moving upward.
[0032]
The operation plate 26 is rotatably attached to the upper edge of the guide plate 25, and normally protrudes from the guide plate 25 at a substantially right angle by a spring 30 that connects the operation plate 26 and the guide plate 25. Held in a state. Only when a force with a magnitude exceeding a preset allowable range is applied to the operation plate 26, the operation plate 26 rotates in a direction to release the force. A position adjusting screw 31 (see FIG. 3) for adjusting the length of the guide plate 25 in the vertical direction is provided on the upper portion of the guide plate 25.
[0033]
Next, FIG. 3A is a front view including a perspective view of the fall prevention device 20, and FIG. In FIG. 3B, a state in which the lever 24 protrudes from the housing 22 is indicated by a solid line, and a state in which the lever 24 is accommodated in the housing is indicated by an alternate long and short dash line. Here, illustration of the cover 23 is omitted.
[0034]
As shown in FIG. 3, the housing 22 is supported by both side walls of the housing 22 and has a shaft 32 for rotatably mounting the lever 24, and a holding shaft protruding from the side wall of the lever 24. The roller catch 33 that holds the lever 24 in the retracted position accommodated in the housing by sandwiching the 24a, the micro switch 34 that contacts the lever 24 and detects the movement of the lever 24 to the retracted position, and the housing 22 A stopper rubber 35 is provided below the opening 22a to hold the lever 24 in a protruding position by contacting the lever 24 when the lever 24 is operated in a direction protruding from the opening 22a. A return plate 27 is fixed to the lower portion of the lever 24 via a curved rod-shaped fixing member 36.
[0035]
However, the return plate 27 is attached so that it is in a position retracted from the lifting path of the pallet 4 when the lever 24 is in the protruding position, and is in a position protruding into the lifting path of the pallet 4 when the lever 24 is in the retracted position. ing. A position adjusting screw 37 for adjusting the protruding amount of the return plate 27 is provided at a connection portion between the return plate 27 and the fixing member 36.
[0036]
Further, the center of gravity of the lever 24 including the return plate 27 and the fixing member 36 is located at the front upper side of the shaft 32 (where “front” refers to the front wall side of the housing 22 when viewed from the shaft 32; the same applies hereinafter). When the operation from the outside is not applied, the lever 24 moves to the protruding position where it abuts against the stopper rubber 35 by its own weight and is held at the protruding position. In this embodiment, the center of gravity of the lever 24 is located in front of the shaft 32 even when the lever 24 is in the retracted position. However, the roller catch 33 holds the holding shaft 24a with a strength sufficient to overcome its own weight. The lever 24 in position is held in that position.
[0037]
Although not shown, a signal line outlet for taking out a detection signal of the microswitch is provided on the side wall of the housing 22. Further, in FIG. 3B, the position of the microswitch 34 is indicated by a dotted line, and the return plate 27 and the fixing member 36 are not a cross-sectional view but a side view thereof.
[0038]
Next, operation | movement of the fall prevention apparatus 20 of this embodiment is demonstrated along FIG.
First, as shown in FIG. 4A, an initial state is considered in which the guide plate 25 is at the lower limit of the moving range due to its own weight, and the lever 24 is also in the protruding position in contact with the stopper rubber 35 due to its own weight. At this time, the swinging end of the lever 24 protrudes from the opening 22a of the housing and the notch 25a of the guide plate 25 at a position facing the opening 22a to the outside, that is, the lifting path of the pallet 4.
[0039]
Next, when the pallet 4 rises from below the lever 24, as shown in FIG. 4B, the lever 24 rotates toward the retracted position side by pushing up the pallet 4 that contacts the lower edge. Move. Accordingly, the pallet 4 reaches the holding position indicated by the one-dot chain line in FIG. 4A beyond the installation position of the lever 24.
[0040]
Note that the rotation by the contact of the pallet 4 prevents the holding shaft 24 a of the lever 24 from reaching the position where it is held by the roller catch 33. For this reason, the lever 24 released from contact with the pallet 4 by the passage of the pallet 4 returns to the protruding position shown in FIG. Accordingly, the lever 24 returned to the protruding position prevents the pallet 4 held at the holding position from dropping.
[0041]
On the other hand, when the pallet 4 is lowered, the pallet 4 held at the holding position is once further raised. Then, as shown in FIG. 4C, the pallet 4 comes into contact with the operation plate 26, so that the guide plate 25 formed integrally with the operation plate 26 rises together with the pallet 4. Then, the roller 29 provided at the lower end of the notch 25a of the guide plate 25 is raised while contacting the lower edge of the lever 24, so that the lever 24 is rotated and pushed to the retracted position inside the housing 22. Instead, the return plate 27 that operates integrally with the lever 24 projects into the lifting path of the pallet 4.
[0042]
At this time, the roller catch 33 clamps the holding shaft 24a of the lever 24 moved to the retracted position, and at the same time, the micro switch 34 contacts the lever 24 to detect that the lever 24 is retained at the retracted position. A detection signal is output. Based on this detection signal, the control device 10 reverses the moving direction of the pallet 4 and starts the descent of the pallet 4.
[0043]
Note that the operating region in which the guide plate 25 moves up and down in conjunction with the pallet 4 is limited by the length of the long hole 25b of the guide plate 25 and the mounting position of the pin 28, and the pallet 4 is lifted beyond the operating region. Sometimes, the operating plate 26 attached to the guide plate 25 is rotated via the spring 30. That is, even if the pallet 4 moves more than necessary, an excessive force is applied to the connecting portion between the operation plate 26 and the guide plate 25 and the pin 28 for attaching the guide plate 25 to the housing 22. It is made not to end up.
[0044]
Next, when the pallet 4 is lowered, the guide plate 25 is lowered in conjunction with each other, so that the contact between the roller 29 and the lever 24 is released, and when the guide plate 25 reaches the lower limit of the operation range, the operation with the pallet 4 is performed. The contact with the plate 26 is also released. However, the lever 24 with the holding shaft 24a held between the roller catches 33 is held in the retracted position. For this reason, the pallet 4 can continue to descend further without being obstructed by the lever 24.
[0045]
Then, the pallet 4 that has passed through the installation position of the lever 24 comes into contact with the return plate 27 protruding in the lifting path, and pushes down the return plate 27. As a result, the lever 24 released from the roller catch 33 rotates to its protruding position by its own weight, and returns to the initial state shown in FIG.
[0046]
In this embodiment, the lever 24 corresponds to a movable member, the guide plate 25, the operation plate 26, and the roller 29 correspond to an interlocking mechanism, the return plate 27 and the fixing member 36 correspond to a first return operation mechanism, and the roller catch 33 corresponds to a restraining means. .
As described above, in the fall prevention device 20 of the present embodiment, the lever 24 that is in contact with the rising pallet 4 is retracted from the ascending / descending path of the pallet 4 and thereafter the contact with the pallet 4 is released. And return to the original protruding position by its own weight.
[0047]
Further, when the pallet 4 is lowered from the holding position, if the pallet 4 is once lifted from the holding position and the guide plate 25 is operated, the lever 24 moves to the retracted position, and the pallet 4 passes the installation place of the lever 24. It becomes possible. When the return plate 27 protruding into the lifting path of the pallet 4 when the lever 24 is in the retracted position is pressed down by the pallet 4 descending beyond the installation location of the lever 24, the lever 24 is protruded from the retracted position. Have been to return to.
[0048]
As described above, according to the fall prevention device 20 of the present embodiment, the lever 24 is driven by the lifting and lowering operation of the pallet 4 without using an electromagnetic solenoid. Therefore, it is necessary to provide a dedicated power source for driving the lever 24. In addition, since there is no such power supply, it is not necessary to take measures against leakage due to rainwater or the like, the apparatus configuration can be simplified, and the apparatus can be manufactured at low cost.
[0049]
Further, according to the fall prevention device 20 of the present embodiment, no wiring other than the micro switch 34 is required, and there is almost no need to replace electrical parts. Can be operated at low cost because the power consumption is small and the power consumption is small.
[0050]
Furthermore, according to the fall prevention device 20 of the present embodiment, the lever 24 is operated using a strong driving force such as the lifting and lowering movement of the pallet 4, and therefore when the movement of the lever 24 becomes worse due to rust or freezing. However, it can be forcibly operated, and as a result, rust and freezing are removed, so that the operating state of the lever 24 can be returned to a good state.
[0051]
Further, the guide plate 25 and the operation plate 26 for transmitting the movement of the pallet 4 to the lever have a simple configuration in which the lever 24 is moved by moving up and down together with the pallet 4 and contacting the lever 24. Failure is unlikely to occur and high reliability can be obtained.
[0052]
  In this embodiment, the roller catch 33 is used to hold the lever 24 in the retracted position. However, the holding state can be released by operating the lever 24 strongly, such as a magnet catch or a ball catch. Any material can be used as long as it is appropriate.
[Reference example]
  nextReference exampleWill be described.
[0053]
  In addition,Reference example2, the fall prevention device 40 is fixed to each of the pillars P as shown by dotted lines in FIG.
  Here, FIG.Reference exampleIt is a perspective view showing the external appearance of this fall prevention device 40.
  As shown in FIG. 5, the fall prevention device 40 includes a housing 41 having a pair of side walls disposed opposite to each other, a front wall connecting both side walls, a shaft 42 supported by both side walls, and the shaft. One end is pivotally supported by 42, and the other end (hereinafter referred to as “swinging end”) is a lever 43 that is inserted into and removed from a notch 41 a formed in the upper portion of the front wall of the housing 41, and the upper portion of the housing 41. And a retraction operation link member 45 that supports the roller 44 at the upper part of the lever 43 and operates integrally with the lever 43, and a return plate 46 that projects from the lower part of the housing 41 and operates integrally with the lever 43. ing.
[0054]
6A is a front view including a perspective view of the fall prevention device 40, and FIG. 6B is a YY sectional view thereof. In FIG. 6B, a state where the lever 43 is in a protruding position protruding from the housing 41 is indicated by a solid line, and a state where the lever 43 is in a retracted position accommodated in the housing is indicated by a two-dot chain line.
[0055]
As shown in FIG. 6, a stopper 47 having an L-shaped cross section is fixed to the lever 43, and the lever 43 is retracted from the lifting / lowering path of the pallet 4 on the side wall constituting the housing 41. A protrusion 41b is formed which contacts the stopper 47 and prevents the lever 43 from rotating beyond the retracted position. Further, a screw hole 41 c for fixing the fall prevention device 40 to the column P is formed on one side wall constituting the housing 41.
[0056]
That is, the lever 43 is in contact with the front wall of the housing 41, and a protruding position where the swing end of the lever 43 projects into the lifting path of the pallet 4 and a stopper of the lever 43 are formed on the side wall of the housing 41. The swinging end of the lever 43 is configured to swing between the retracted position retracted from the lifting path of the pallet 4 in contact with the protrusion.
[0057]
However, when the lever 43 is in the retracted position, the center of gravity of the lever 43 including the roller 44, the retracting operation link member 45, and the return plate 46 is located behind the shaft 42. The retraction position is set so that it cannot be restored. The return plate 46 is mounted so that it is in a position retracted from the lifting path of the pallet 4 when the lever 43 is in the protruding position, and is in a position protruding into the lifting path of the pallet 4 when the lever 43 is in the retracted position. ing. Further, the retracting operation link member 45 is set so as to obtain a displacement that rotates the lever 43 to the retracted position when the roller 44 contacts the pallet 4.
[0058]
  next,Reference exampleThe operation of the fall prevention device 40 will be described with reference to FIG.
  First, as shown in FIG. 7A, consider an initial position where the lever 43 is in a protruding position in contact with the front wall of the housing 41 due to its own weight. At this time, the swing end of the lever 43 protrudes from the notch 41 a of the housing 41 to the outside, that is, the lifting path of the pallet 4.
[0059]
Next, when the lever 43 comes into contact with the pallet 4 rising from below, the lever 43 is rotated toward the retreat position side by pushing up the pallet 4 as shown in FIG. Accordingly, the pallet 4 reaches the holding position indicated by the one-dot chain line in FIG. 7A beyond the installation position of the lever 43.
[0060]
In the rotation due to the contact of the pallet 4, the lever 43 does not reach the retracted position, and the lever 43 rotates within the range where the center of gravity of the lever 43 is located on the upper front of the shaft 42. For this reason, the lever 43 released from contact with the pallet 4 by the passage of the pallet 4 returns to the protruding position shown in FIG. Accordingly, the lever 43 returned to the protruding position prevents the pallet 4 held at the holding position from dropping.
[0061]
On the other hand, when the pallet 4 is lowered, the pallet 4 held at the holding position is once further raised. Then, as shown in FIG. 7C, when the pallet 4 comes into contact with the roller 44, the lever 43 moves to the retracted position, and instead, the return plate 46 that operates integrally with the lever 43 is attached to the pallet 4. Projects into the lifting path.
[0062]
Then, the raising / lowering mechanism of the pallet 4 raises the pallet 4 to a position where it abuts on the roller 44, then reverses the moving direction of the pallet 4 and starts to lower the pallet 4.
At this time, even if the pallet 4 starts to descend, the lever 43 that has reached the retracted position remains held at the retracted position. For this reason, the pallet 4 can continue to descend further without being obstructed by the lever 43.
[0063]
Then, the pallet 4 that has passed through the installation position of the lever 43 comes into contact with the return plate 46 that protrudes into the lifting path, and pushes down the return plate 46. As a result, when the lever 43 rotated in the direction in which the stopper 47 moves away from the protrusion 41b is rotated to a position where the center of gravity is located in front of the shaft 42, the lever 43 is rotated to the protruding position by its own weight. Return to the initial state shown in FIG.
[0064]
Less thanAs explained above,Reference exampleIn the fall prevention device 40, the lever 43 that is in contact with the rising pallet 4 is retracted from the lifting path of the pallet 4, and then when the contact with the pallet 4 is released, the lever 43 returns to the original protruding position by its own weight. It is supposed to return.
[0065]
Further, when the pallet 4 is lowered from the holding position, if the pallet 4 is once lifted from the holding position and the roller 44 is displaced, the lever 43 moves to the retracted position, and the pallet 4 passes the installation position of the lever 43. It becomes possible. When the return plate 46 that protrudes into the lifting path of the pallet 4 when the lever 43 is in the retracted position is pressed down by the pallet 4 that descends beyond the installation location of the lever 43, the lever 43 protrudes from the retracted position. Have been to return to.
[0066]
  in this way,Reference exampleSince the lever 4 is driven by the raising / lowering operation of the pallet 4 without using an electromagnetic solenoid, the same effect as the fall prevention device 20 of the first embodiment can be obtained.
  Also,Reference exampleAccording to the fall prevention device 40, the roller 44 for transmitting the movement of the pallet 4 to the lever 43, the retraction operation link member 45, and the return plate 46 are all configured to operate integrally with the lever. Therefore, failure is unlikely to occur and high reliability can be obtained.
[0067]
[Second Embodiment]
  In addition,Reference example aboveThen, the retraction operation link member 45 and the return plate 46 are configured separately, and each is fixed to the lever 43 individually. However, the retraction operation link member 45 and the return plate 46 are integrated. A link member 48 may be used and attached so as to operate integrally with the lever 43. In this case, for example, as shown in FIG. 8, if the shaft 42 is configured to operate integrally with the lever 43, the link member 48 is fixed to the shaft 42 that protrudes to the outside of the housing 41. May be.
  In the present embodiment, the lever 43 corresponds to a movable member, and the roller 44 and the link member 48 correspond to a retraction operation member and a first return operation mechanism.
[Third Embodiment]
  Next, a third embodiment will be described.
[0068]
  The fall prevention device 50 of the present embodiment is used to prevent the pallet 4 held at the 2nd to (N-1) th stages from falling in an N (N ≧ 3) stage multilevel parking lot.
  In addition, the fall prevention device 50 of this embodiment isReference exampleSince only a part of the configuration is different from that of the fall prevention device 40, the same components are denoted by the same reference numerals and description thereof is omitted.
[0069]
That is, as shown in FIG. 9, the fall prevention device 50 of this embodiment includes a return operation link member 55 that holds the roller 54 further above the roller 44 held by the retraction operation link member 45.
The return operation link member 55 is swingably attached to a shaft 51 fixed to the side wall of the casing 41, and when not operated, the supporting end that supports the roller 54 is placed on the pallet above the roller 44 by its own weight. 4, the other operating end is disposed at a position where it abuts against the stopper 47 of the lever 43 in the retracted position. When the roller 54 abuts against the pallet 4 and the supporting end is displaced, the operation is performed accordingly. The end is configured to be displaced in a direction in which the lever 43 is rotated toward the protruding position.
[0070]
Each of the retraction operation link member 45 and the return operation link member 55 includes tip link members 45a and 55a serving as roller support ends and other main link members 45b and 55b. The tip link members 45a and 55a are attached to the main link members 45b and 55b at an angle, and when pressed by the pallet 4 descending from above, the tip link members 45a and 45a By bending 55a with respect to the main link members 45b and 55b, the pallet 4 is allowed to pass without displacing the main link members 45b and 55b, and returns to the original shape when the contact with the pallet 4 is released. It is configured.
[0071]
The return operation link member 55 is formed on the side wall on the opposite side of the pair of side walls constituting the housing 41 from the one on which the projection 41b is formed so that the operation is not restricted by the projection 41b. Has been. Accordingly, the lever 43 is provided with a similar stopper 47 not only on the surface facing the side wall on which the protrusion 41b is formed, but also on the other surface.
[0072]
The operation of the fall prevention device 50 configured as described above will be described with reference to FIGS. 9 and 10. However, the fall prevention device 50 is assumed to prevent the pallet 4 from dropping at the n (where 2 ≦ n ≦ N−1) stage holding position.
As shown in FIG. 10F, when the pallet 4 is raised from the (n-1) th stage holding position to the nth stage holding position, and when the pallet 4 is moved from the nth stage holding position to (n-1). The operation for lowering to the stage holding position is exactly the same as in the second embodiment, so the description thereof is omitted here, and the pallet 4 is raised from the nth stage holding position to the (n + 1) th stage holding position. And the operation when moving from the (n + 1) th stage holding position to the nth stage holding position will be described.
[0073]
First, when the pallet 4 rising from the n-th holding position toward the (n + 1) -th holding position comes into contact with the roller 44, the displacement of the roller 44 caused by the contact moves through the retraction operation link member 45 to the lever. As shown in FIG. 9A, the lever 43 moves to the retracted position. When the pallet 4 further rises and contacts the roller 54, the displacement of the roller 54 caused by the contact is transmitted to the lever 43 via the return operation link member 55, whereby the lever 43 moves to the protruding position. Thereafter, when the roller 54 is released from contact with the pallet 4, as shown in FIG. 9C, the return operation link member 55 swings due to its own weight, and the roller 54 projects into the lifting path of the pallet 4. Return to the original position.
[0074]
Next, when the pallet 4 descending from the (n + 1) -th holding position toward the n-th holding position comes into contact with the roller 54, as shown in FIG. Displace. Thereby, the pallet 4 passes the installation area | region of the roller 54, without rocking the main link member 55b.
[0075]
When the pallet 4 further descending beyond the installation area of the roller 54 contacts the roller 44, only the tip link member 45a is displaced together with the roller 44, as shown in FIG. Thereby, the pallet 4 passes the installation area | region of the roller 44, without displacing the main link member 55b. That is, as shown in FIG. 10F, when the pallet 4 reaches the n-th holding position, the lever 43 is in the protruding position.
[0076]
In the present embodiment, the roller 54 and the return operation link member correspond to a second return operation mechanism.
As described above, in the fall prevention device 50 of the present embodiment, when the pallet 4 rises from the n-th holding position to the n + 1-th holding position, the lever 43 comes into contact with the roller 44 so that the lever 43 is retracted. The lever 43 returns to the protruding position by continuously abutting on the roller 54 even when the lever 43 is moved. Therefore, it is possible to prevent the pallet 4 that has been lifted from the n−1th stage holding position and newly held at the nth stage holding position from falling.
[0077]
Further, in the fall prevention device 50 of the present embodiment, even if the pallet 4 descending from the (n + 1) -th holding position to the n-th holding position contacts the rollers 54 and 55, the return operation link member 55 swings. Therefore, the pallet 4 can be safely lowered while holding the lever 43 in the protruding position.
[0078]
That is, the fall prevention device 50 according to the present embodiment prevents the pallet 4 from dropping from the holding position of the n (2 ≦ n ≦ N−1) stage in the N (≧ 3) stage multilevel parking lot. This can be realized only by raising and lowering the pallet 4 without using a dedicated power source for driving the pallet.
[Fourth Embodiment]
Next, a fourth embodiment will be described.
[0079]
  In addition, the fall prevention device 60 of this embodiment isReference exampleAs in the case of the fall prevention device 40, each is fixed to each support P (see FIG. 2).
  FIG. 11 is an explanatory diagram showing the internal configuration and operation of the fall prevention device 60 of the present embodiment. The fall prevention device 60 includes a casing 61 having a pair of side walls disposed opposite to each other. Here, in order to make the drawing easier to see, one side wall is removed and viewed from the removed side. A side view is shown.
[0080]
As shown in FIG. 11, the fall prevention device 60 is mounted on a lever 63 for mounting a stopper 62 formed in a rod shape, a shaft 64 for swingably supporting the lever 63, and the lever 63. By abutting on the upper surface of the stopper 62, the stopper 64 protrudes from the front surface (left side in the figure) of the housing 61 to the lifting path of the pallet 4 and is held in a substantially horizontal state (hereinafter referred to as “projecting position”). Thus, a first restricting member 65 that restricts the swing range of the lever 63 is provided.
[0081]
The lever 63 on which the stopper 62 is placed has a center of gravity on the front side of the housing from the shaft 64, is held at the protruding position by its own weight, and is rotated by being pushed up from the lower side to the protruding end. It is configured.
Further, the fall prevention device 60 holds the holding shaft 63a projecting from the rear end of the lever 63 toward the side wall when the lever 63 is rotated to the retracted position retracted from the lifting path of the pallet 4. A roller catch 66 that holds the lever 63 in the retracted position, and a position that contacts the rear end so that the stopper 62 does not slide off the lever 63 when the lever 63 rotates between the protruding position and the retracted position. And a second restricting member 67 provided.
[0082]
Further, the fall prevention device 60 is swingably supported on the side wall of the casing 61, has rollers 68a and 68b at both ends, and when the lever 63 is in the protruding position, the mounting end (hereinafter referred to as "working end") of the roller 68b. ”) Comes into contact with the rear end of the lever 63, and the retraction operation link member 68 in which the attachment end (hereinafter referred to as“ passive end ”) of the roller 68a projects into the elevating path of the pallet 4 above the stopper 62 and one end. Is rotatably supported by the shaft 64, provided with a roller 69a at the other end, and a return operation link member 69 bent in an L shape toward the lifting path side.
[0083]
Among these, when the external force is not applied, the retracting link member 68 is held in a state where the passive end protrudes into the lifting path as shown in FIG. When the passive end is displaced by the contact of the pallet 4, the working end is displaced in a direction to push down the rear end of the lever 63, and the lever 63 is moved to the retracted position where the roller catch 66 operates.
[0084]
On the other hand, the return link member 69 is provided in the vicinity of the shaft 64 when the roller 69a is positioned almost directly below the shaft 64 due to its own weight when the external force is not applied and the lever 63 is displaced toward the retracted position. As shown in FIG. 11 (b), the roller 69 b thus brought in contact with the lever 63 rotates together with the lever 63. When the lever 63 is held at the retracted position, the attachment end (hereinafter referred to as “passive end”) of the roller 69a protrudes into the lifting path.
[0085]
Next, operation | movement of the fall prevention apparatus 60 of this embodiment is demonstrated along FIG.
First, as shown in FIG. 11A, when the lever 63 is in the projecting position, the lever 63 and the stopper 62 placed on the lever 63 project into the lifting path of the pallet 4.
[0086]
Next, when the lever 63 comes into contact with the pallet 4 rising from below, the lever 63 is rotated toward the retracted position side by pushing up the pallet 4 as shown in FIG. As a result, the pallet 4 reaches the holding position indicated by the one-dot chain line in FIG. 11A beyond the installation position of the lever 63.
[0087]
Since the lever 63 does not reach the retracted position by the rotation due to the contact of the pallet 4, the lever 43 released from the contact with the pallet 4 by the passage of the pallet 4 is caused by its own weight as shown in FIG. Return to the protruding position shown in. Therefore, the lever 63 and the stopper 62 returned to the protruding position prevent the pallet 4 held at the holding position from dropping.
[0088]
On the other hand, when the pallet 4 is lowered, the pallet 4 held at the holding position is once further raised. Then, as shown in FIG. 11C, when the pallet 4 comes into contact with the roller 68a at the passive end of the retraction operation link member 68, the lever 63 moves to the retraction position and is held by the roller catch 66. The roller 69 a at the passive end of the return operation link member 69 pushed out by the lever 63 projects into the lifting path of the pallet 4. At this time, the stopper 62 is retracted to the position where it comes into contact with the second restricting member 67 together with the lever 63.
[0089]
Thus, once the lever 63 reaches the retracted position, it remains held at the retracted position even if the lifting mechanism of the pallet 4 reverses the moving direction of the pallet 4 and lowers the pallet 4. Therefore, the pallet 4 can be further lowered without being obstructed by the lever 63.
[0090]
Then, as shown in FIG. 11 (d), the pallet 4 that has passed through the installation position of the lever 63 comes into contact with the roller 69a at the passive end of the return operation link member 69 that protrudes into the lifting path, and displaces it. Then, the lever 63 is also rotated by being pushed by the roller 69b of the return operation link member 69. As a result, the lever 63 whose holding shaft 63a is released from being held by the roller catch 66 is rotated to the protruding position by its own weight, Returning to the initial state shown in FIG.
[0091]
In this embodiment, the stopper 62 and the lever 63 correspond to a movable member, the retraction operation link member 68 corresponds to a retraction operation member, the return operation link member 69 corresponds to a first return operation mechanism, and the roller catch 66 corresponds to a restraining means.
As described above, in the fall prevention device 60 of the present embodiment, the lever 63 that is in contact with the ascending pallet 4 is retracted from the ascending / descending path of the pallet 4 together with the stopper 62, and thereafter is in contact with the pallet 4. When it is released, it returns to the original protruding position together with the stopper 62 by its own weight.
[0092]
Further, when the pallet 4 is lowered from the holding position, if the pallet 4 is once lifted from the holding position and the roller 68a of the retraction operation link member 68 is displaced, the lever 63 moves together with the stopper 62 to the retraction position, 4 will be able to pass through the installation location of the lever 43. When the roller 69a of the return operation link member 69 that protrudes into the lifting path of the pallet 4 when the lever 63 is in the retracted position, the pallet 4 descending beyond the installation location of the lever 63 comes into contact and is displaced. Is configured to return from the retracted position to the protruding position together with the stopper 62.
[0093]
Thus, according to the fall prevention device 60 of the present embodiment, the lever 4 is driven by the lifting and lowering operation of the pallet 4 without using an electromagnetic solenoid. Therefore, the same effect as the fall prevention device 20 of the first embodiment is obtained. Can be obtained.
As mentioned above, although several embodiment of this invention was described, this invention is not limited to the said embodiment, In the range which does not deviate from the summary of this invention, it is possible to implement in various aspects. is there.
[0094]
For example, in the above embodiment, the levers 24 and 43 of the fall prevention devices 20, 40, and 50 are configured to protrude and retract from the lifting path of the pallet 4, but move together with the pallet 4. You may comprise so that it may protrude and retract | save with respect to the movement path | route of the member to perform and the pallet 4 for raising / lowering operation.
[0095]
In the second and third embodiments, only the movement of the center of gravity of the lever 43 is used to hold the lever 43 in the retracted position. However, as in the first and fourth embodiments, a roller catch or the like is used. A restraining means may be provided.
In particular, when a restraining means such as a roller catch is provided, it is desirable to provide an urging means comprising a spring or the like that urges the levers 24, 43, 63 toward the protruding position. In this case, the levers 24, 43, 63 released from the restraint by the restraining means can be surely automatically returned to the protruding position.
[Brief description of the drawings]
FIG. 1 is a perspective view illustrating an appearance of a fall prevention device according to a first embodiment.
FIG. 2 is an explanatory diagram showing a configuration of a multi-story parking lot where a fall prevention device is installed.
FIGS. 3A and 3B are a front view and a sectional view taken along line XX of the fall preventing device according to the first embodiment. FIGS.
FIG. 4 is an explanatory diagram illustrating the operation of the fall prevention device according to the first embodiment.
[Figure 5]Reference exampleIt is a perspective view showing the external appearance of this fall prevention device.
[Fig. 6]Reference exampleIt is the front view and YY sectional drawing of the fall preventive device.
[Fig. 7]Reference exampleIt is explanatory drawing showing operation | movement of this fall prevention apparatus.
FIG. 8 is a second embodiment.OutsideIt is a perspective view showing a view.
FIG. 9 is an explanatory diagram illustrating the configuration and operation of a fall prevention device according to a third embodiment.
FIG. 10 is an explanatory diagram illustrating the configuration and operation of a fall prevention device according to a third embodiment.
FIG. 11 is an explanatory diagram illustrating the configuration and operation of a fall prevention device according to a fourth embodiment.
[Explanation of symbols]
2 ... three-dimensional parking machine, 4 ... pallet, 6 ... lifting mechanism, 8 ... motor, 10 ... control device, 12, 13 ... sprocket, 14, 15 ... chain, 16, 17 ... drive shaft, 20, 40, 50, 60 ... fall prevention device, 21 ... mounting plate, 22, 41, 61 ... housing, 22a ... opening, 23 ... cover, 24, 43, 63 ... lever, 24a, 63a ... holding shaft, 25 ... guide plate, 26 ... Operation plate, 27 ... Return plate, 28 ... Pin, 29,44,54 ... Roller, 30 ... Spring, 31,37 ... Position adjusting screw, 32,42,64 ... Shaft, 33,66 ... Roller catch, 34 ... Micro Switch, 35 ... stopper rubber, 36 ... fixing member, 45, 68 ... retraction operation link member, 46 ... return plate, 47 ... stopper, 48 ... link member, 51 ... shaft, 55, 69 ... return operation link member, 62 ... Strike Pa, 65 ... first limiting member, 67 ... second limiting member, K ... digits, P ... struts.

Claims (11)

A fall prevention device for preventing a displacement body that moves up and down and is held at a preset holding position from falling from the holding position,
The displacement body is configured to be movable between a protruding position that protrudes in the lifting path and a retracted position that is retracted from the lifting path, and at the protruding position, the passage of the displacement body that descends from the holding position is prevented. Abutting directly or indirectly on the displacement body rising toward the holding position, and moving the displacement body to the retracted position side along with the rise of the displacement body, A movable member that automatically returns to the protruding position when contact is released, and that cannot automatically return to the protruding position at the retracted position;
Covering the front wall of the housing in which the opening for inserting and removing the movable member is formed, and attached to the housing so as to be movable in the ascending / descending direction of the displacement body along the front wall, the opening A guide plate having a notch formed in a portion opposed to the guide plate, and projecting from the upper portion of the guide plate toward the elevating path of the displacement body, and the displacement body in an operation region set above the holding position. when the there has an operating plate Ru is lifting movement the guide plate in association with the displacement body, the time to increase the guide plate, the movable member the lower end of the notch portion comes into contact with the lower edge of said movable member An interlocking mechanism for moving to a retracted position;
When the movable member is in the retracted position, the movable member abuts on the displacement body that descends beyond the installation position of the movable member and is displaced so that the movable member can be automatically returned from the retracted position to at least the protruding position. A first return movement mechanism that moves to a position;
A fall prevention device comprising:   The fall prevention device according to claim 1, further comprising a restraining unit that restrains the movable member at the retracted position at the retracted position.   The fall prevention device according to claim 2, further comprising a biasing unit that biases the movable member toward the protruding position. The fall prevention device according to any one of claims 1 to 3, wherein a roller is provided at a lower end of the notch. A fall prevention device for preventing a displacement body that moves up and down and is held at a preset holding position from falling from the holding position,
The displacement body is configured to be movable between a protruding position that protrudes in the lifting path and a retracted position that is retracted from the lifting path, and at the protruding position, the passage of the displacement body that descends from the holding position is prevented. Abutting directly or indirectly on the displacement body rising toward the holding position, and moving the displacement body to the retracted position side along with the rise of the displacement body, A movable member that automatically returns to the protruding position when contact is released, and that cannot automatically return to the protruding position at the retracted position;
The movable member is provided integrally with the movable member. When the movable member is in the projecting position, the movable member projects to the lifting path of the displacement body at the upper portion of the holding position, and displaces when the movable member abuts on the displacement body. A retraction member that moves to a retraction position;
When the movable member is in the retracted position, the movable member abuts on the displacement body that descends beyond the installation position of the movable member and is displaced so that the movable member can be automatically returned from the retracted position to at least the protruding position. A first return movement mechanism that moves to a position;
With
The first return operation mechanism is provided integrally with the movable member. When the movable member is in the retracted position, the first return operation mechanism protrudes into a lifting path of the displacement body at a lower portion of the movable member and contacts the descending displacement body. A return motion member that displaces
The restoration member and the saving operation member drop under prevention device characterized in that it consists of a single member from the. The fall prevention device according to claim 5, further comprising a restraining unit that restrains the movable member at the retracted position at the retracted position. The fall prevention device according to claim 6 , further comprising a biasing unit that biases the movable member toward the protruding position. A fall prevention device for preventing a displacement body that moves up and down and is held at a preset holding position from falling from the holding position,
The displacement body is configured to be movable between a protruding position that protrudes in the lifting path and a retracted position that is retracted from the lifting path, and at the protruding position, the passage of the displacement body that descends from the holding position is prevented. Abutting directly or indirectly on the displacement body rising toward the holding position, and moving the displacement body to the retracted position side along with the rise of the displacement body, A movable member that automatically returns to the protruding position when contact is released, and that cannot automatically return to the protruding position at the retracted position;
A retraction operation mechanism that displaces in contact with a displacement body that rises beyond the holding position and moves the movable member to the retraction position;
When the movable member is in the retracted position, the movable member abuts on the displacement body that descends beyond the installation position of the movable member and is displaced so that the movable member can be automatically returned from the retracted position to at least the protruding position. A first return movement mechanism that moves to a position;
A second return operation mechanism that contacts and displaces a displacement body that rises beyond the operating region of the retraction operation mechanism, and moves the movable member from the retraction position to a position where at least the automatic return to the protruding position is possible; ,
A fall prevention device comprising:   The second return operation mechanism is pivotally supported, and has a projecting end projecting into the lifting path above the operation area of the retraction operation mechanism, and an operation end contacting the movable member at the retraction position. 9. A drop according to claim 8, wherein the operating end comprises a displacement member that is displaced in a direction of moving the movable member toward the protruding position by displacement of the protruding end caused by contact of the displacement body. Prevention device.   The fall prevention device according to claim 8 or 9, further comprising a restraining means for restraining the movable member at the retracted position to the retracted position.   The fall prevention device according to claim 10, further comprising a biasing unit that biases the movable member toward the protruding position.

Images