JP2000342354A - Safety mechanism of moving rack device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the certainty and safety of the operation by mounting a lateral frame member deformable or movable according to the displacement of a width of a path, and forbidding the deformation or the movement of the lateral frame member in the operation. SOLUTION: When an adjacent rack 2 is moved and a predetermined width H of a path is obtained, a lateral frame member 3 is opened, and one end 32a of a link at the other side is not positioned at an upper part of a locking shaft 42. As a result, the locking shaft 42 is projected by a coil spring to be engaged with one end 32a side edge of the link at the other side, which forbids the rotation in the closing direction of the link 32 at the other side, and the lateral frame member 3 of which the deformation is forbidden by a lock means 4 acts as a prop, whereby the movement of the rack 2 in the direction to narrow the width of the path is prevented. When a braid member is stretched and the locking shaft 42 is hidden, an unlocking means 5 is operated, the locking shaft 42 is rotated by the torsional force of the coil spring, and a fixing pin mounted on the locking shaft 42 is engaged with a downward surface of a projection body, whereby the locking shaft 42 is prevented from being projected, the links 31 and 32 are rotated to each other, and the rack 2 becomes movable.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to a mobile rack apparatus comprising a plurality of racks movable along rails, and has a function of securing a passage between racks in an emergency such as an earthquake. The present invention relates to a safety mechanism for a movable rack device.

[0002]

2. Description of the Related Art In a moving rack apparatus of this type, an operator moves a rack as necessary, and enters and exits a desired rack by entering a passage formed between adjacent racks. This is characterized in that space can be saved as compared with the fixed rack device.

On the other hand, in such a moving rack apparatus, the movement of the rack is prohibited by locking the wheels in order to prevent the rack from moving and pinching a person in the passage between the racks. Is known. Specifically, in the case of a handle type manual rack, the chain connecting the handle and the wheel is not moved, and in the case of the electric rack, the motor is not moved.

Further, in order to ensure higher safety, one end of the long member is pivotally supported at a middle portion of a column provided at a corner on the entrance side of the rack of the rack. The elongate member is held in an upright position along the rack when the person enters the passage.
There is also known an apparatus in which the elongate member is tilted and rotated by 0 degrees to be in a horizontal state, and this long material is used as a push rod to secure a passage width between racks.

[0005]

However, for example, in the former case, that is, in the case of only locking the wheels, the wheels can slide on the rails. In the event of a collision for some reason or a large earthquake, it is difficult to ensure sufficient safety in terms of securing the width of the passage. Further, even in the latter case where the long material is replaced with a stick, if each rack is deformed or skewed in a large earthquake or the like, if the tip of the long material hits the column of the rack. The reliability of the safety is relatively low because there is a possibility of buckling without hitting at a right angle even if it hits, or even if hit. Furthermore, even if the passage width can be ensured, since the long material is horizontal at the middle part of the rack, the long material may hinder the evacuation.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem at once, and it is intended that the racks be moved between upper and lower racks while being maintained between the upper ends thereof. By providing a transverse member that can be deformed or movable in accordance with the displacement of the passage width, and by prohibiting the transverse member from being deformed or moved during operation, the reliability of operation is improved and safety is improved. It is intended to make it happen.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The moving rack apparatus according to the present invention is applied to a moving rack apparatus comprising a plurality of racks movable along rails, and a passage formed between arbitrary adjacent racks is provided. This is for inhibiting the width from becoming smaller than a predetermined width, and while maintaining a state of being bridged between the upper end portions of adjacent racks, a laterally deformable or movable side can follow the displacement of the passage width due to the movement of these racks. A bridge member, a lock unit that can be operated in a state where the passage width matches the predetermined width to prevent deformation or movement of the horizontal member, and a lock for releasing the operation of the lock unit. Release means.

[0008] According to such a configuration, since the horizontal members are arranged so as to always straddle between adjacent racks, even if each rack is deformed or skewed, it is the same as the above-mentioned conventional one. In the first place, the problem that the tip of the long material does not hit the column of the adjacent rack cannot occur, and this horizontal member reliably works like a push rod to secure the passage width. Needless to say, the passage width can be ensured even if the rack moves due to the sliding between the rail and the wheels. Therefore, the reliability in securing the passage width can be greatly improved as compared with the conventional one. Further, since the horizontal members are disposed between the upper ends of the racks, the doors do not hinder access to the passage even during operation, and the evacuation is not hindered. In addition, it can be used as a lock device for securing a passage width not only in an emergency but also in a normal use.

In order to ensure that the locking means is automatically activated when the passage is formed, and to eliminate the need for the operator to perform a special operation for activating the locking means,
It is preferable that the lock means which is in the operation released state by the lock release means is configured to be in an operation standby state by moving the rack so as to reduce the passage width from the predetermined width.

In a specific embodiment which is easy to realize with a simple structure, a horizontal member connects one end of a pair of link elements so as to be rotatable with each other, and connects the other end to the upper end of an adjacent rack. Are rotatably connected to each other,
Locking means for inhibiting the rotation of these link elements to thereby inhibit deformation of the transverse member can be mentioned.

In such a horizontal member, when the link elements are configured to be linear when the passage has a predetermined width,
Even if the passage width is reduced from the predetermined width, the link elements do not rotate, and the movement of the rack may be hindered. In order to surely avoid such a point, it is desirable that the link elements be formed in a U-shape in an opened state in which the passage width matches the predetermined width.

In order to contribute to the reduction of the number of members and the like, and to enable the realization with a simple configuration, the locking means is provided on one of the link elements and is engaged with an engaging position which can be engaged with the other link element. And a resilient urging member for resiliently urging the locking portion in the direction of the engaging position. A locking element that can be immovably fixed by setting the locking portion at the engagement position to a predetermined posture is provided, and the locking portion is formed by utilizing an elastic biasing material that constitutes the locking means. It is desirable that the elastic member is elastically biased in a direction of a predetermined posture.

More specifically, the locking means includes a locking shaft serving as a locking portion supported and rotatably supported by a holding member attached to one of the link elements, and a locking direction in which the locking shaft projects. A coil spring, which is an elastic urging member, which elastically urges the lock shaft, and the locking shaft protruded to the engagement position by the extension force of the coil spring is engaged with one end side edge of the other link element. It has a function of locking the link elements so as not to rotate in mutually adjacent directions, and the unlocking means includes an engaging element provided on the locking shaft and a fixing element provided on the holding body, By rotating the locking shaft at a predetermined angle in a retracted position, which is a non-engaging position where the rotation of the link elements is not prohibited, the engaging element is engaged with the fixed element and the protrusion of the locking shaft is prohibited. Yes, using the torsion force of the coil spring The engagement of the locking shaft and the fixed element and the engagement element may include those that are rotationally urged in the direction to engage.

In order to effectively prevent the worker from forgetting to release the lock when exiting the passage after finishing the work, the unlocking means can be operated by a string member hanging downward at substantially the center in the width direction of the passage. It is preferred that
As a particularly preferred embodiment for the electric rack, there can be cited one in which the horizontal member is provided with a wiring holding space for holding an electric cable or the like.

[0015]

An embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the mobile rack apparatus 1 according to the present embodiment has a plurality of racks 2 arranged on a plurality of rails R laid on the floor so as to be parallel to each other, and the racks 2 are connected to the rails R. , So that a passage S extending perpendicular to the rail R can be formed between the arbitrary racks 2. In the present embodiment, each rack 2 is described as being driven by an electric motor driven by a built-in electric motor, but may be driven by a handle or manually driven by pushing the rack itself.

The rack 2 includes a bottom plate 21, a top plate 25,
It comprises left and right side plates 22 and a plurality of shelf plates 24. Although not shown, the bottom plate portion 21 includes a bottom frame member serving as an outer frame, and a plurality of reinforcement members extending in the direction in which the rails R extend on the bottom frame member. Wheels that roll on R are installed. A plurality of columns are erected between the top plate 25 and the bottom plate portion 21 at equal intervals so as to connect the respective front edges and the rear edges. The support column 26 is a hollow rectangular pipe, and a plurality of hook holes (not shown) are horizontally penetrated on its inner surface so that the shelf plate 24 can be selectively mounted at an arbitrary height. The left and right side plates 22 are provided so as to cover from the outside the columns 26 erected from the corners of the bottom plate portion 21, and rubber members 221 for preventing finger jamming are provided on the side edges thereof. It is attached. The shelf board 24 is a thin casing having an open lower surface, and is attached by engaging claws (not shown) provided on both left and right ends thereof with hook holes of the support column 22.

In this embodiment, however, the horizontal rack which can be deformed or moved following the displacement of the passage width due to the movement of these racks 2 while maintaining the state of being bridged between the upper ends of the adjacent racks 2. The material S and the passage S
A lock means 4 which operates at a time when the width reaches a predetermined width H to inhibit the deformation of the horizontal member 3 to restrict the passage width from being reduced, and a lock release means for releasing the operation of the lock means 4 5 is provided.

Each part of the safety mechanism will be described in detail. As shown in FIGS. 2 to 7, the horizontal member 3 includes a pair of link elements 3.
1 and 32, and each link element 31, 32
Are mainly composed of channel members 31b and 32b opening upward. Thus, one end portion 31a of one link element 31 is made substantially disk-shaped,
One end 32a of the other link element 32 is formed in a plate shape having a smaller area than the one end 31a of one link element 31. And one end 31a of one link element 31
One end 32a of the other link element 32 is disposed so as to overlap with the other, and these are connected to each other by a pin 33 so as to be horizontally rotatable, and the other ends 31c and 32c of the link elements 31 and 32 are adjacent to each other. The racks 2 are connected to a top plate 25 of the rack 2 to be rotatable horizontally. The reason that the link elements 31, 32 are mainly composed of the channel members 31b, 32b is to obtain sufficient strength while maintaining a light weight.
The space surrounded by the bottom wall and both side walls of the cable can be used as a wiring holding space P for holding electric cables and the like.

In the state in which the adjacent racks 2 are in contact with each other and the passage S is not formed at all, the horizontal member 3 configured as above is bent inward as shown in FIG.
When the passage width matches the predetermined width H, as shown in FIGS. 3 and 4, the angle between the link elements 31 and 32 is bent inward, which is larger than the closed shape, as shown in FIGS. It has a substantially U-shape in plan view, that is, an open molded shape.

As shown in FIGS. 8 and 9, the locking means 4 is connected to one end 31 of one of the link elements 31 located on the lower side.
a holding body 41 attached to the lower surface;
Shaft 42 supported to be movable up and down, and this locking shaft 4
A coil spring 43 for elastically urging the link element 2 in the protruding direction, and the locking shaft 4 provided at one end 31 a of one link element 31.
2 through which an insertion hole 42a can be inserted. The locking shaft 42 protruding upward through the insertion hole 42a is caused to contact the other link element 32, so that the link elements 31, 32 do not rotate in a direction in which the angle between them becomes smaller. In order to prevent the passage width from shrinking below the predetermined width H.

The locking means 4 will be described in detail. The holding body 41 includes a cylindrical holding body 411 having a closed lower surface, a flange 413 integrally provided at the upper end of the holding body 411, A lid 412 is screwed to an upper end of the holder main body 411 and closes an upper surface opening thereof. Each end of the locking shaft 42 is supported by insertion holes 414 and 415 provided in a lid 412 constituting the holding body 41 and a bottom plate of the holding body 411, respectively.
12 is configured so as to be able to protrude and retract between a protruding position protruding from the upper surface of the holding member 12 and a submerging position submerging in the holding body 41.

The coil spring 43 is mounted so as to be wound around the locking shaft 42. More specifically, the locking shaft 42
One end is fixed to a fixing pin 52 attached to a middle portion of the holding member so as to extend in the radial direction.
The other end is fixed to one bottom plate. The extension force elastically urges the locking shaft 42 in the protruding direction. The insertion hole 42 a has substantially the same diameter as the locking shaft 42, and is penetrated from a side of the one end 31 a of one of the link elements 31 from a little to the tip. More specifically, as shown in FIGS. 3 and 4, when the horizontal member 3 is in an open-molded state, it does not overlap with one end 32a of the other link element 32, and as shown in FIG. When the material 3 has a closed shape or a shape between the closed shape and the open molded shape, at least a part thereof is provided at a portion overlapping with one end 32 a of the other link element 32.

That is, this locking means 4 is
Has a closed shape or a shape between the closed shape and the open molded shape, the upper end of the locking shaft 42 is suppressed by the lower surface of the other link element 32 so that the locking shaft 42 cannot be protruded. In the case of, as shown in FIG. 8, the locking shaft 42 projects upward to engage with the side edge 32d of the one end 32a of the other link element 32, and the other link element 32 is moved in the closed shape direction. A lock operation state where rotation is prohibited may be obtained.

As shown in FIGS. 8 to 11, the lock releasing means 5 is for fixing the locking shaft 42 constituting the locking means 4 to the retracted position so that the locking operation cannot be performed.
A fixing pin 52 serving as an engaging element provided on the locking shaft 42, a downward surface 53 serving as a fixing element capable of locking the fixing pin 52 in a state where the locking shaft 42 is in the retracted position, An elastic urging member that elastically urges the locking shaft 42 to rotate the locking shaft 42 so as to engage the pin 52 with the downward surface 53, and a string member 51 as an operation unit for operating the unlocking means 5 are provided. I do.

Each part of the unlocking means 5 will be described in detail. The fixing pin 52 is connected to the locking shaft 42 as described above.
Is attached to the intermediate portion by press fitting or the like so as to extend perpendicular to the axial direction. The downward face 53 is
A pair of protrusions 53 protruding from the lower surface of the lid 412
The lower surface of A plays that role. These projections 53A are disposed so as to be symmetrical with respect to the center of the lid 412.

The coil spring 43 constituting the locking means 4 also serves as the elastic biasing member. That is, since one end of the coil spring 43 is fixed to the fixing pin 52 and the other end is fixed to the bottom plate of the holding body 41, the torsion force applies a rotational force to the locking shaft 42. obtain. The string member 51 is attached to the lower end of the locking shaft 42, and by pulling the string member 51, the locking shaft 42 can be retracted to the retracted position.

When the cord member 51 is pulled downward and the locking shaft 42 is located at the retracted position, the coil spring 43
Rotates the locking shaft 42, and the fixing pin 52 is engaged with the downward surface 53 of the protruding body, thereby preventing the locking shaft 42 from projecting. In addition, a stopper pin 531 that prohibits the locking shaft 42 from being excessively rotated by the torsion force of the coil spring 43 protrudes from the downward surface 53 of the protruding body 53A.

Further, in this embodiment, a return means 6 for returning the lock means 4 in the unlocked state by the lock release means 5 to the operation standby state is provided. The return means 6 includes an arm 61 provided at the lower end of the locking shaft 42 and a biasing member 62 provided on the other link element 32 for biasing the arm. Arm 61 is locking shaft 4
2 is a round bar-shaped member extending in the horizontal direction so as to be orthogonal to 2.

The biasing member 62 is in the form of a piece suspended from one end 32a of the other link element 32. When the other link element 32 is rotated from the open molded state to the closed state, the biasing member 62 rotates. The locking shaft 42 hits the arm 61
Is rotated in a direction in which the engagement between the fixing pin 52 and the downward surface 53 of the protruding body 53A is released. Next, the operation of the safety device according to the present embodiment and the handling method thereof will be described below.

When the passage S is not formed between the adjacent racks 2, as shown in FIG. 2, the horizontal member 3 has a closed shape, and the locking means 4 is configured such that the upper end of the locking shaft 42 is closed. The other link element 32 is in an operation standby state in which it is suppressed by the lower surface of the one end 32a and cannot protrude. Therefore, the movement of these racks 2 is not prohibited. From this state, when one of the adjacent racks 2 is moved so as to increase the passage width, and the passage width reaches a predetermined width H, the horizontal member 3 becomes an open molded shape, and one end 32 a of the other link element 32 is formed. Is no longer located above the locking shaft 42. As a result, the locking shaft 4
2 protrudes due to the extension force of the coil spring 43 and engages with the side edge of the other end 32a of the other link element 32 to inhibit the other link element 32 from rotating in the closed shape direction, ie, FIG. The lock operation state shown in FIGS. In this state, since the horizontal member 3 whose deformation is prohibited by the lock means 4 works like a push rod,
The rack 2 cannot be moved in a direction to narrow the passage width.

After the passage S is formed in this way, when the worker goes out after finishing the work in the passage S, for example, the worker pulls the string member 51 to position the locking shaft 42 at the immersion position.
At this time, since the string member 51 hangs from the center near the passage entrance, it is possible to effectively prevent the worker from forgetting to pull the string member 51. As a result of this operation, as shown in FIGS. 4, 9 and 11, the lock release means 5 is operated to enter the lock release state. That is, the locking shaft 42 is rotated by the torsion force of the coil spring 43 and the locking shaft 42 is rotated.
The locking pins 52 provided on the projections are engaged with the downwardly facing surfaces 53 of the protruding bodies to prevent the locking shafts 42 from protruding, so that the link elements 31 and 32 can rotate again to move the rack 2. It becomes possible to do this.

Then, when the next worker moves the rack 2 so as to reduce the above-mentioned passage width so as to form a passage S between the other racks 2, for example, the link elements 31, 32 are brought closer to each other. In response to this, the urging member 62 provided on the other link element 32 contacts the arm 61 provided at the lower end of the locking shaft 42, and the locking shaft 42 is fixed against the torsion force of the coil spring 43. Pin 52 and protrusion 53
A is rotated in a direction in which the engagement with the downward surface 53 is released. The fixing pin 52 and the downward surface 53 of the protrusion 53A
Is released, the locking shaft 42 tends to protrude due to the extension force of the coil spring 43. But in this state,
As shown in FIG. 6, the upper end of the locking shaft 42 is suppressed by the lower surface of the one end 32 a of the other link element 32 and can only slightly protrude. That is, the above-mentioned lock unit 4 is in the operation standby state.

According to the safety mechanism of this embodiment constructed as described above, since the horizontal members 3 are arranged so as to always straddle between the adjacent racks 2, each rack 2 is deformed or skewed. In this case, the horizontal member 3 reliably works like a stick to secure the passage width. Needless to say, even if the rack 2 moves due to the sliding between the rail R and the wheels, the passage width can be secured. Therefore, in terms of securing the passage width, the reliability for safety can be greatly increased. Furthermore, since the horizontal member 3 is disposed between the upper ends of the racks 2, it does not hinder access to the passage S even during operation, does not hinder evacuation, and has a good appearance.

In the conventional device, the safety mechanism may not operate due to operational mistakes such as forgetting to lock the wheels or forgetting to set the long material in the horizontal position. According to the embodiment, the locking means 4 relating to the rack 2 in which the passage S is not formed is always in the operation standby state, and by moving the rack 2 so that the passage S has the predetermined width H from this state, the locking means 4 has no effect. Even if no special operation is performed, the lock means 4 always operates automatically. Therefore, safety can be further improved.

It should be noted that the present invention is not limited to the above-described embodiment, and various modifications are possible. For example, if the rack width is long, the horizontal member may be bridged not only near the entrance of the passage but also at a plurality of locations. It is also possible to adopt a configuration in which the horizontal member can be slid relative to the rack, and the locking means can prevent the horizontal member from sliding relative to the rack. Further, the lock release means is not limited to the configuration of the above embodiment, but may be adapted to the mode of the horizontal member, or an electromagnetic mechanism may be used. In addition, in the above embodiment, when the passage is widened to a predetermined width, the locking means always operates automatically,
For example, the locking means may be operated manually, or a mechanism may be provided so that the user can select whether to automatically operate the locking means or manually.

The specific configuration of each part is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

[0037]

According to the present invention described in detail above, since the horizontal members are arranged so as to always straddle between adjacent racks, even if each rack is deformed or skewed, the conventional structure is used. In the first place, there is no possibility that the end of the long member does not hit the column of the adjacent rack as in the case of the above, and this cross member reliably works like a push rod to secure the passage width. Needless to say, the passage width can be ensured even if the rack moves due to the sliding between the rail and the wheels.
Therefore, the reliability in securing the passage width can be greatly improved as compared with the conventional one. In addition, since the horizontal members are located between the upper ends of the rack,
Even during the operation, there is an effect that the vehicle does not hinder access to the passage and does not hinder evacuation.

If the lock means, which is in the operation released state by the lock release means, is configured to be in the operation standby state by moving the rack so that the width of the passage is narrowed from the predetermined width, the passage becomes a predetermined state. By moving the rack to the width, the locking means always operates automatically. That is, since the operator is not required to perform a special operation for operating the locking means, it is possible to avoid a situation in which the locking means does not operate due to forgetting to operate or the like, and to further improve safety. Become.

A horizontal member rotatably connects one end of the pair of link elements to each other and rotatably connects the other end to an upper end of an adjacent rack. However, if the rotation of these link elements is prohibited, so that the deformation of the horizontal member is prohibited,
Realization with a simple configuration becomes possible. In such a horizontal member, when the link elements are configured to be linear when the passage has a predetermined width, the link elements do not rotate even when the passage width is reduced from the predetermined width, and the movement of the rack is hindered. However, if the link elements are formed in a U-shape in the opened state in which the passage width matches the predetermined width, the above-described risk can be reliably avoided.

The locking means includes a locking shaft rotatably supported by a holder attached to one of the link elements and rotatably supported by the holding member, and a coil spring for elastically biasing the locking shaft in a protruding direction. By engaging the locking shaft projected by the extension force of the coil spring with the other link element, the link element has a function of locking the link elements so as not to rotate in mutually adjacent directions. The means includes an engaging element provided on the locking shaft and a fixing element provided on the holding body, and by rotating the locking shaft at a predetermined angle in a retracted position where rotation of the link elements is not prohibited. , The engaging element and the fixing element can be engaged with each other to protrude the locking shaft, and the locking shaft can be fixed to the engaging element by using the torsion force of the coil spring. Energize rotationally in the direction in which the element engages As long as you are, because it can promote commonality of components of the locking means and the unlocking means,
This can contribute to simplifying the structure and reducing the number of parts.

If the unlocking means can be operated by a string member hanging downward at substantially the center in the width direction of the passage, it is possible to effectively prevent the worker from forgetting to unlock when exiting the passage after finishing the work. Can be prevented. If the horizontal member has a wiring holding space for holding an electric cable or the like, wiring to each rack can be suitably performed without providing a dedicated wiring mechanism in the electric rack.

[Brief description of the drawings]

FIG. 1 is a schematic overall perspective view of a moving rack apparatus showing one embodiment of the present invention.

FIG. 2 is a plan view showing a safety mechanism in the embodiment.

FIG. 3 is a plan view showing a safety mechanism in the embodiment.

FIG. 4 is a plan view showing a safety mechanism in the embodiment.

FIG. 5 is a side view in FIG. 2;

FIG. 6 is a schematic front view in FIG. 2;

FIG. 7 is a partial perspective view of the safety mechanism in the embodiment as viewed obliquely from below.

FIG. 8 is a partial vertical sectional view of the holder in the embodiment.

FIG. 9 is a partial vertical cross-sectional view of the holder in the embodiment.

FIG. 10 is a schematic sectional view taken along line XX in FIG. 8;

FIG. 11 is a schematic sectional view taken along line YY in FIG. 9;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 2 ... Rack 3 ... Horizontal member 31, 32 ... Link element 31a, 31b ... One end part 4 ... Lock means 41 ... Holder 42 ... Locking shaft 43 ... Coil spring 5 ... Lock release means 51 ... String member 52 ... Engagement Element (fixing pin) 53: fixing element (downward surface) R: rail S: passage H: predetermined width P: wiring holding space

Claims (7)

[Claims] The present invention is applied to a mobile rack apparatus having a plurality of racks movable along rails, and for preventing a passage formed between arbitrary adjacent racks from becoming narrower than a predetermined width. A transverse member capable of being deformed or moved following the displacement of the passage width due to the movement of these racks while maintaining a state of being bridged between the upper ends of adjacent racks; A locking means that can be operated in a locked state to prohibit deformation or movement of the horizontal member, and a lock releasing means for releasing the operation of the locking means. Mobile rack equipment safety mechanism. 2. The system according to claim 1, wherein the lock means, which has been released from the operation by the lock release means, is in an operation standby state by moving the rack so as to reduce the passage width from the predetermined width. The safety mechanism of the moving rack device as described in the above. 3. A bridge member having one end of a pair of link elements rotatably connected to each other, and the other end rotatably connected to an upper end of an adjacent rack. 3. The safety mechanism for a movable rack device according to claim 1, wherein the lock means prohibits rotation of the link elements to thereby prevent deformation of the horizontal member. 4. The movable rack safety mechanism according to claim 3, wherein the link elements are formed in a U-shape when the passage width matches the predetermined width. 5. A locking shaft, wherein said locking means is rotatably supported by a holding body attached to one link element so as to be able to protrude and retract, and a coil spring for elastically urging said locking shaft in a protruding direction. It has a function of locking the link elements so as not to rotate in mutually adjacent directions by engaging the locking shaft projected by the extension force of the coil spring with the other link element, The lock release means includes an engaging element provided on the locking shaft and a fixing element provided on the holder, and rotates the locking shaft by a predetermined angle at a retracted position where rotation of the link elements is not prohibited. With this configuration, the engaging element and the fixing element can be engaged with each other to protrude the locking shaft, and the locking shaft can be connected to the engaging element by using the torsion force of the coil spring. And the fixed element The safety mechanism for a mobile rack apparatus according to claim 3, 4 or 5, wherein 6. The movable rack device safety mechanism according to claim 1, wherein the unlocking means is operable by a string member hanging downward at substantially the center of the passage in the width direction. 7. The horizontal member is provided with a wiring holding space for holding an electric cable or the like.
7. The safety mechanism for a mobile rack device according to 4, 5, or 6.