Reversing walking mechanism, shuttle vehicle and stereoscopic storage rack

Abstract

The application provides a reversing walking mechanism, a shuttle vehicle and a stereoscopic storage rack, comprising: a bottom plate, which is formed with a plurality of avoidance notches; a plurality of hub motors, which are respectively arranged in each avoidance notch to have a first walking state of walking along the transverse direction and a second walking state of walking along the longitudinal direction; a reversing module, which comprises a crank structure arranged on the bottom plate and a plurality of elbow connecting rods arranged in a circumferential array on the crank structure, each elbow connecting rod being connected to each hub motor, so that each hub motor is linked through each elbow connecting rod to switch between the first walking state and the second walking state when the crank structure rotates. The application solves the technical problem of the prior art that the complex structure of the transmission mechanism leads to increased difficulty in subsequent maintenance such as machining and assembly.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of shuttle vehicles, in particular to a reversing walking mechanism, a shuttle vehicle and a stereoscopic storage rack. BACKGROUND

[0002] The existing four-way shuttle vehicle adopts at least eight wheel arrangement, four wheels as a group; when driving in one direction, one group of wheels is used, when driving in the orthogonal direction, the other group of wheels is usually lowered, and at the same time the vehicle body and the front group of wheels are lifted off the track surface, and the rear group of wheels drives the operation. In order to ensure that both groups of wheels have driving ability, a complex transmission mechanism is arranged inside the vehicle to transmit the driving motor torque, which undoubtedly increases the difficulty of machining, assembly and maintenance, and reduces the system reliability. The shuttle vehicle runs in the stereoscopic warehouse, and it is difficult for maintenance personnel to reach, so when the vehicle fails, it can automatically drive out to the maintenance position, so the reliability of the walking part is required.

[0003] Since the shuttle vehicle needs to reverse in place, in order to avoid interference between the wheels and the track, the track usually needs to be provided with a gap for the guide wheel to pass through. Dense gaps will cause the vehicle to run stably, increase noise, and the existing solution is to increase the number of wheels to 12 or even 16 or more, and also ensure that all have driving ability, further increasing the complexity of the vehicle and the difficulty of maintenance, and reducing the reliability. SUMMARY

[0004] In view of the deficiencies in the prior art, the present application provides a reversing walking mechanism, a shuttle vehicle and a stereoscopic storage rack, which solves the technical problem of the prior art that the complex transmission mechanism structure increases the difficulty of subsequent maintenance such as machining and assembly.

[0005] According to an embodiment of the present application, the reversing walking mechanism comprises:

[0006] The bottom plate is formed with a plurality of avoidance notches;

[0007] A plurality of hub motors are respectively arranged in each of the avoidance notches to have a first walking state of walking along the transverse direction and a second walking state of walking along the longitudinal direction;

[0008] The reversing module comprises a crank structure rotatably arranged on the bottom plate and a plurality of elbow connecting rods arranged in a circumferential array on the crank structure, each of the elbow connecting rods being connected to each of the hub motors, so that each of the hub motors is switched between the first walking state and the second walking state through the linkage of each of the elbow connecting rods when the crank structure rotates.

[0009] Preferably, the elbow connecting rod is formed with a first hinge point and a second hinge point, and the first hinge point and the second hinge point are respectively connected to the crank structure and the hub motor.

[0010] Preferably, in the first walking state and the second walking state, the line connecting the first articulation point and the second articulation point is collinear with the crank structure; and / or

[0011] When the hub motor switches between the first walking state and the second walking state, the rotation angles of the crank structure and the hub motor are α1 and α2, respectively, and α1 and α2 satisfy α1 = 2α2.

[0012] Preferably, the two adjacent first articulation points are arranged in a staggered manner in the up-down direction.

[0013] Preferably, the elbow connecting rod is formed with a mounting gap.

[0014] Preferably, the reversing walking mechanism further comprises a plurality of mounting modules, each of which is arranged on each hub motor, and each mounting module comprises:

[0015] a mounting seat arranged on the bottom plate;

[0016] a rotating arm rotatably arranged on the mounting seat, the rotating arm being formed as an integral elbow arm for connecting with the elbow connecting rod; and

[0017] a wheel frame hingedly connected to one end of the rotating arm and hingedly connected to the other end of the rotating arm through a shock absorber, the hub motor being mounted on the wheel frame and protruding from the avoidance gap.

[0018] Preferably, the upper and lower end faces of the mounting seat are each formed with a groove, two thrust bearings are respectively embedded in the corresponding grooves, and the upper thrust bearing is covered by a retaining ring, the rotating arm being connected to the retaining ring after passing through the inner rings of the two thrust bearings.

[0019] Preferably, the bottom plate is provided with a plurality of guide wheels, each of which is arranged close to each hub motor.

[0020] On the other hand, according to an embodiment of the present application, a shuttle vehicle is also provided, comprising the above-mentioned reversing walking mechanism.

[0021] Preferably, the shuttle vehicle further comprises a housing arranged on the bottom plate, the housing being driven by a lifting mechanism arranged on the bottom plate to move along the up-down direction.

[0022] On the other hand, according to an embodiment of the present application, a three-dimensional storage rack is also provided for cooperating with the above-mentioned shuttle vehicle, the three-dimensional storage rack comprising a plurality of transverse tracks and a plurality of longitudinal tracks in communication.

[0023] Preferably, the proximal ends of the transverse tracks and the longitudinal tracks are respectively provided with transverse gaps and longitudinal gaps.

[0024] Compared with the prior art, the present application has the following beneficial effects:

[0025] 1. The hub motor is driven by the reversing module, so that the hub motor can rotate at the avoidance gap, forming a first walking state along the transverse direction and a second walking state along the longitudinal direction, thereby changing the traditional jacking reversing mode to a rotary reversing mode, reducing the driving power and mechanical load, improving the efficiency; Furthermore, in both walking states, the same set of hub motors walks, the number of wheels is greatly reduced, the transmission mechanism is simplified, the modularization degree is high, the processing and assembly difficulty is reduced, the maintenance is convenient, and the cost is reduced;

[0026] 2. The reversing module includes a crank structure rotating on the bottom plate, and a plurality of elbow connecting rods arranged in a circular array on the crank structure, each elbow connecting rod is connected to each hub motor, so that when the crank structure rotates, it drives each elbow connecting rod to rotate to link each hub motor to rotate, thereby switching the hub motor between the first walking state and the second walking state, simplifying the transmission structure; At the same time, each hub motor is connected to each elbow connecting rod, so that the plurality of hub motors are independently driven, when a single hub motor fails, the remaining hub motors can still walk normally, ensuring that the mechanism has enough power to drive out to the open maintenance position in the fault mode, avoiding the situation that the machine is down or the maintenance personnel cannot reach. High reliability and easy maintenance. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 It is a structure schematic view of the reversing walking mechanism in an embodiment of the present application;

[0028] Figure 2 It is a structure schematic view of the mounting module in an embodiment of the present application;

[0029] Figure 3 It is a sectional view of the mounting module in an embodiment of the present application;

[0030] Figure 4 It is a layout principle diagram of the reversing walking mechanism before reversing in an embodiment of the present application;

[0031] Figure 5 It is a layout principle diagram of the reversing walking mechanism after reversing in an embodiment of the present application;

[0032] Figure 6 It is a structure schematic view of the array four elbow connecting rods in an embodiment of the present application;

[0033] Figure 7 It is an explosion view of the shuttle vehicle in an embodiment of the present application;

[0034] Figure 8This is a schematic diagram of the structure of a shuttle vehicle in one embodiment of the present invention;

[0035] Figure 9 This is a partial structural schematic diagram of a three-dimensional storage rack in one embodiment of the present invention;

[0036] Figure 10 for Figure 9 A sectional view;

[0037] Figure 11 This is a partial structural schematic diagram of a three-dimensional storage rack in one embodiment of the present invention;

[0038] Figure 12 for Figure 11 A magnified view of a portion of point A in the middle.

[0039] In the above attached figures:

[0040] 1. Base plate; 101. Clearance notch; 2. Hub motor; 3. Cross crank; 4. Elbow connecting rod; 401. Mounting notch; 5. Mounting seat; 6. Swing arm; 601. Bending arm; 7. Wheel frame; 8. Shock absorber; 9. Thrust bearing; 10. Retaining ring; 11. Guide wheel; 12. Housing; 13. Transverse track; 14. Transverse gap; 15. Longitudinal track; 16. Longitudinal gap. Detailed Implementation

[0041] The technical solutions of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0042] In embodiments of the present invention, such as Figures 1-6 As shown, the reversing travel mechanism includes a base plate 1, multiple hub motors 2, and a reversing module. The base plate 1 has multiple clearance notches 101. The multiple hub motors 2 are rotatably disposed on each of the clearance notches 101 to have a first travel state of traveling laterally and a second travel state of traveling longitudinally. The reversing module includes a crank structure rotatably disposed on the base plate 1 and multiple elbow connecting rods 4 arranged in a circumferential array on the crank structure. Each elbow connecting rod 4 is connected to each of the hub motors 2 so that when the crank structure rotates, the elbow connecting rods 4 will link each hub motor 2 to switch between the first travel state and the second travel state.

[0043] Specifically, in the embodiments of the present invention, such as Figure 1As shown, the four top corners of the bottom plate 1 are respectively formed with a avoiding gap 101, and the four wheel hub motors 2 are respectively installed at each avoiding gap 101, and the wheel hub motor 2 can omit a large number of transmission components, so that the vehicle structure is simpler; it has the characteristics of single wheel independent driving, and can realize various complex driving modes; each wheel hub motor 2 can rotate relative to the bottom plate 1 to have a first walking state of walking along the transverse direction and a second walking state of walking along the longitudinal direction; in this way, when the wheel hub motor 2 switches between the first walking state and the second walking state, different walking directions can be switched, so that the traditional jacking type reversing mode is replaced by the rotating type reversing mode through the rotation of the wheel hub motor 2, thereby reducing the driving power, reducing the mechanical load, and improving the efficiency; Furthermore, in the first walking state or the second walking state, the mechanism uses the same set of wheel hub motors 2 to walk, without the need to additionally increase another set of wheels, greatly reducing the number of wheels, thereby making the assembly difficulty low, the maintenance more convenient, and the cost reduced.

[0044] In the embodiment of the application, as shown Figure 1 In order to be able to drive each wheel hub motor 2 to rotate in each avoiding gap 101 to switch between the first walking state and the second walking state, the center of the bottom plate 1 is provided with a crank structure (since this embodiment adopts four wheel hub motors 2, the crank structure here is a cross crank 3), the cross crank 3 is driven to rotate by a servo motor and a speed reducer (not shown), and the four ends of the cross crank 3 are respectively connected with each wheel hub motor 2 through each elbow connecting rod 4, so that the rotation of the cross crank 3 drives the elbow connecting rod 4 to rotate, and then the elbow connecting rod 4 drives each wheel hub motor 2 to rotate to change the current walking state of the wheel hub motor 2. Four wheel hub motors 2 are driven by one cross crank 3 and four elbow connecting rods 4, which simplifies the transmission structure and is easy to assemble and maintain; Furthermore, the cross crank 3 can simultaneously drive each wheel hub motor 2 to rotate through each elbow connecting rod 4, so that each wheel hub motor 2 can realize the purpose of synchronous reversing in place; At the same time, each elbow connecting rod 4 is independent of each other, and when a single wheel hub motor 2 fails, it does not affect the rotation of the remaining wheel hub motors 2 linked by the other elbow connecting rods 4, so that each wheel hub motor 2 can operate independently and without interference; Even after failure, the remaining wheel hub motors 2 can move the mechanism to a vacant maintenance position for easy maintenance.

[0045] The present application drives the cross crank 3 to rotate 180° by a servo motor and a speed reducer, thereby driving the wheel hub motor 2 to rotate 90° through the elbow connecting rod 4 (i.e. the wheel hub motor 2 switches from transverse walking to longitudinal walking, and vice versa), to replace the traditional multi-wheel jacking reversing mode, greatly reducing the number of wheels and simplifying the transmission mode, so as to reduce the processing and assembly difficulty, maintain conveniently and reduce the cost.

[0046] As shown Figure 1As shown, in an embodiment, the elbow link 4 is formed with a first hinge point and a second hinge point, which are connected to the crank structure and the hub motor 2 respectively. Specifically, in order to make the cross crank 3 rotate 90° through the elbow link 4 to drive each hub motor 2, the embodiment forms the first hinge point and the second hinge point at two ends of the elbow link 4 respectively, so as to make the elbow link 4 hinge to the cross crank 3 and the hub motor 2 through the two hinge points respectively, thereby forming a crank link structure, and then driving the hub motor 2 to switch between the first walking state and the second walking state.

[0047] Further, in an embodiment, as shown, Figure 4 O1 is the center of the mechanism, and O2 is the rotation center of one of the four hub motors 2, and a circle is drawn according to the size of the hub motor 2 to define its running track. A straight line is drawn from O1 to the circle, and intersects the circle at points A and B. The two points AB are the hinge points of the hub motor 2 and the second hinge point of the elbow link 4 before and after the commutation (the first walking state and the second walking state). Since the hub motor 2 rotates 90° during commutation, O2A is perpendicular to O2B, that is, the rotation angles of the crank structure and the hub motor 2 when the hub motor 2 switches between the first walking state and the second walking state are α1 and α2 respectively, and α1 and α2 satisfy α1 = 2α2.

[0048] In the first walking state and the second walking state, the line connecting the first hinge point and the second hinge point is collinear with the crank structure. Specifically, in order to use the four elbow links 4 for self-locking, as shown, Figure 5As shown, if the hub motor 2 needs to be driven to steer, a four-bent link 4 can be used for self-locking. To make the four-bent link 4 self-locking, the two-force lever principle of the link (i.e. the direction of the force is along the direction of the connecting line of the two hinged points) is used to make the force on the bent link 4 directly act on the rotation center O1 of the cross crank 3, so that additional torque is not generated, thereby achieving self-locking. That is, the cross crank 3 (middle axis) and the bent link 4 (connecting line of the two hinged points) are collinear before and after reversing. Then select point C in the direction of the extension of the O1AB connecting line, and form the cross crank 3 with O1, AC forms the bent link 4, rotates 180° around O1 to reach point D, and the corresponding A point moves to point B. O1O2AC forms the bent link 4. The rotation center O1 of the cross crank 3 is driven by a servo motor and a speed reducer, and the length of the cross crank 3 is O1C, which is half the length of AB. Draw a broken line between AC to avoid interference between the rotation center and the drive shaft. According to kinematic analysis, the force on point C is perpendicular to the instantaneous speed direction, and the pressure angle is 90°, which has self-locking capability. Since the bent link 4 is a two-force lever, its shape does not affect the direction of force transmission. It can be understood that the bent link 4 has two hinged points and a turning point, which forms a mounting notch 401 for avoiding interference with the corresponding parts. The larger the mounting notch 401, the more parts can be avoided, so as not to cause interference, so as to fully utilize the structural space of the mechanism. Therefore, the bent link 4 only needs to meet the above requirements, and its shape can be other shapes except for the embodiment, which is not limited here.

[0049] As shown in Figure 5 , Figure 6 O1O2AC is arranged in a circular array around O1, thereby forming a four-wheel self-locking reversing walking mechanism. Among them, the middle four cranks can be combined into a cross-shaped crank. In order to make the adjacent two links not interfere with each other, the adjacent two first hinged points are arranged in a staggered manner in the upward and downward directions.

[0050] As shown in Figure 2As shown, in one embodiment, the reversing travel mechanism further includes multiple mounting modules, each mounting module being disposed on each of the hub motors 2. Each mounting module includes a mounting base 5, a rotating arm 6, and a wheel frame 7. The mounting base 5 is disposed on the base plate 1. The rotating arm 6 is rotatably disposed on the mounting base 5, and the rotating arm 6 forms an integral curved arm 601 for connecting with the elbow connecting rod 4. One end of the wheel frame 7 is hinged to one end of the rotating arm 6, and its other end is hinged to the other end of the rotating arm 6 through a shock absorber 8. The hub motor 2 is mounted on the wheel frame 7 and protrudes from the clearance notch 101. Specifically, to enable the hub motor 2 to turn in place without deflection, this embodiment provides a mounting module for each hub motor 2. This mounting module includes a mounting base 5 fixedly connected to the base plate 1, a rotating arm 6 rotatably engaged with the mounting base 5, and a wheel frame 7 connecting the hub motor 2. The rotating arm 6 forms an integral curved arm 601 for connection to the second hinge point of the elbow connecting rod 4. One end of the wheel frame 7 is hinged to one end of the rotating arm 6, and its other end is connected to the other end of the rotating arm 6 via a shock absorber 8. Thus, when the cross crank 3 rotates 180°, it links the elbow connecting rod 4 to rotate the swing arm 6 by 90°, thereby synchronously driving the hub motor 2 to rotate using the wheel frame 7, and then switching the running direction of the hub motor 2. Since the hub motor 2 rotates around the center of the contact point, the entire vehicle body will not deflect during the reversal, thus achieving reversal on the spot; the shock absorber 8 is used to absorb the vibration generated during the movement of the hub motor 2, improve the adhesion performance between the hub motor 2 and the rail surface, prevent the hub motor 2 from being suspended, and facilitate the synchronization of the four wheel speeds. Of course, since the swing arm 6 needs to be hinged to the elbow connecting rod 4, and the four swing arms 6 are also arranged in a circular array, therefore, Figure 6 As shown in the figure, the rotating arms 6 located at the upper left and lower right are perpendicular to the axis of the hub motor 2, while the rotating arms 6 located at the lower left and upper right are parallel to the axis of the hub motor 2. The four mounting modules can be divided into type A and type B according to the mounting structure. In type A, the curved arm 601 is located at the front of the hub motor 2, while in type B, the curved arm 601 needs to be set on the side of the hub motor 2.

[0051] like Figure 3 As shown, in one embodiment, grooves are formed on both the upper and lower end faces of the mounting base 5. Two thrust bearings 9 are respectively embedded in the corresponding grooves, and the upper thrust bearing 9 is covered by a retaining ring 10. The rotating arm 6 passes through the inner ring of each thrust bearing 9 and is connected to the retaining ring 10. In order to retain only the rotational degree of freedom of the hub motor 2, this embodiment provides grooves on the upper and lower end faces of the mounting base 5, which are arranged opposite to each other for mounting the thrust bearings 9. The upper end of the rotating arm 6 passes through the inner ring of each thrust bearing 9 and is bolted to the retaining ring 10 provided on the mounting base 5 to clamp the two thrust bearings 9 in the middle, thereby constraining five degrees of freedom and retaining only the rotational degree of freedom.

[0052] As Figure 8 shown in the drawings, in an embodiment, the bottom plate 1 is provided with a plurality of guide wheels 11, each of which is arranged close to each of the hub motors 2. Specifically, in order to enable the hub motors 2 to run smoothly in the lateral and longitudinal directions, a guide wheel 11 is arranged on one side of each hub motor 2 (i.e., the bottom plate 1 is provided with four guide wheels 11), and the guide wheel 11 is mounted on the bottom plate 1 by a support to play a guiding role in both lateral and longitudinal running. The guide wheels 11 can also be removed, and a two-dimensional code navigation can be used to enable the shuttle vehicle to run on land and in water.

[0053] The embodiment also provides a shuttle vehicle, which comprises the reversing walking mechanism described above. The specific structure of the reversing walking mechanism is referred to the above embodiment. Since the shuttle vehicle adopts all the technical solutions of the above embodiment, it at least has all the beneficial effects brought by the technical solutions of the above embodiment, which will not be repeated here.

[0054] As Figure 7 , Figure 8 shown in the drawings, in an embodiment, the shuttle vehicle further comprises a shell 12 arranged on the bottom plate 1, and the shell 12 is driven by a lifting mechanism arranged on the bottom plate 1 to move up and down. Specifically, in order to enable the shuttle vehicle to transport and transfer goods, a shell 12 is arranged on the bottom plate 1 to carry goods for easy transfer; in order to protect the reversing walking mechanism of the bottom plate 1, a cover plate can be additionally arranged between the bottom plate 1 and the shell 12 to cover the reversing walking mechanism; a cylinder is arranged at each mounting gap 401 to lift the shell 12 to load and unload goods. Of course, the lifting mechanism can also be other, which is not limited here.

[0055] As Figure 9 shown in the drawings, the embodiment also provides a three-dimensional storage rack for cooperating with the above-described shuttle vehicle. The three-dimensional storage rack comprises a plurality of interconnected lateral tracks 13 and longitudinal tracks 15, so that the shuttle vehicle can freely walk and carry goods in the tracks.

[0056] As Figures 10-12As shown, in an embodiment, the proximal end of the transverse track 13 and the longitudinal track 15 are respectively provided with a transverse gap 14 and a longitudinal gap 16. In order to enable the guide wheel 11 to follow the shuttle in the track, eight gaps, namely the transverse gap 14 and the longitudinal gap 16, are provided at the intersection position of the transverse track 13 and the longitudinal track 15 for the passage of the guide wheel 11. The transverse gap 14 and the longitudinal gap 16 each have an upper notch and a lower notch, the upper notch is smaller and is located on the track support surface for the passage of the support, also enabling the corresponding wheel hub motor 2 to vibrate less when passing through the current gap, and the lower notch is larger for the passage of the guide wheel 11. Since the original reversing is adopted, the transverse track 13 and the longitudinal track 15 do not need to be provided with a height difference, and both are in the same plane, and under the help of the guide wheel 11, the driving of any three wheel hub motors 2 will not cause the vehicle body to be skewed when reversing, ensuring that the vehicle has enough power to drive out of the shelf and move to the empty maintenance position in the fault mode, avoiding the situation of breakdown and rescue in the shelf.

[0057] Finally, it should be pointed out that the above embodiments are only used to illustrate the technical solutions of the present application and are not limiting. Although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present application can be modified or replaced equivalently without departing from the purpose and scope of the technical solutions of the present application, and they should be covered in the scope of the claims of the present application.

Claims

1. A reversing travel mechanism, characterized in that: include: The base plate has multiple clearance gaps; Multiple hub motors are respectively rotatably disposed in each of the aforementioned clearance gaps, so as to have a first traveling state of traveling laterally and a second traveling state of traveling longitudinally; The reversing module includes a crank structure rotatably mounted on the base plate, and a plurality of elbow connecting rods arranged in a circumferential array on the crank structure. Each elbow connecting rod is connected to each of the hub motors, so that when the crank structure rotates, each of the hub motors is linked by the elbow connecting rods to switch between a first travel state and a second travel state. The elbow connecting rod has a first hinge point and a second hinge point, which are respectively connected to the crank structure and the hub motor. In the first and second walking states, the line connecting the first hinge point and the second hinge point is collinear with the crank structure. and / or When the hub motor switches between the first walking state and the second walking state, the rotation angles of the crank structure and the hub motor are α1 and α2, respectively, and α1 and α2 satisfy α1=2α2.

2. The reversing travel mechanism as described in claim 1, characterized in that: The two adjacent first hinge points are staggered in the vertical direction.

3. The reversing travel mechanism as described in claim 1, characterized in that: The elbow connecting rod has an installation notch.

4. The reversing travel mechanism as described in claim 1, characterized in that: The reversing travel mechanism further includes multiple mounting modules, each mounting module being disposed on each of the wheel hub motors, and each mounting module comprising: Mounting base, provided on the base plate; A rotating arm, rotatably mounted on the mounting base, the rotating arm forming an integral curved arm for connection to the elbow connecting rod; and The wheel frame is hinged at one end to one end of the swing arm, and at the other end to the other end of the swing arm via a shock absorber. The hub motor is mounted on the wheel frame and protrudes from the clearance notch.

5. The reversing travel mechanism as described in claim 4, characterized in that: The mounting base has grooves formed on both its upper and lower end faces. Two thrust bearings are respectively embedded in the corresponding grooves, and the upper thrust bearing is covered by a retaining ring. The rotating arm passes through the inner ring of each thrust bearing and connects to the retaining ring.

6. The reversing travel mechanism as described in claim 1, characterized in that: The base plate is provided with multiple guide wheels, and each guide wheel is positioned close to its respective hub motor.

7. A shuttle vehicle, characterized in that, Includes the reversing travel mechanism as described in any one of claims 1-6.

8. The shuttle as described in claim 7, characterized in that, The shuttle also includes a housing covered on the base plate, the housing being driven by a lifting mechanism located on the base plate to move the housing vertically.

9. An automated storage and retrieval system, characterized in that: For use with the shuttle as described in claim 7 or 8, the automated storage rack includes: multiple interconnected transverse tracks and multiple longitudinal tracks.

10. The automated storage rack as described in claim 9, characterized in that, The transverse track and the longitudinal track are respectively provided with transverse gaps and longitudinal gaps at their near ends.

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