CN109178788B

CN109178788B - Blocking mechanism

Info

Publication number: CN109178788B
Application number: CN201810810255.2A
Authority: CN
Inventors: 何波
Original assignee: Shanghai Sunyell Electronic Technology Co ltd
Current assignee: Shanghai Sunyell Electronic Technology Co ltd
Priority date: 2018-07-23
Filing date: 2018-07-23
Publication date: 2020-05-22
Anticipated expiration: 2038-07-23
Also published as: CN109178788A

Abstract

The invention provides a blocking mechanism which comprises a rack, a driving device and a crank assembly, wherein the crank assembly comprises a crank, a curved bar, a guide rail and a blocking piece, the guide rail is vertically and movably arranged on the rack, the blocking piece is arranged at the upper end of the guide rail and protrudes out of the rack, the upper end of the curved bar is rotatably connected with the lower end of the guide rail, the driving device is connected with one end of the crank and is used for driving the crank to rotate, and the other end of the crank is rotatably connected with the lower end of the curved bar. Preferably, a crank stop is included for stopping movement of the crank. The device also comprises a limiting device for limiting the vertical moving stroke of the guide rail. Still include the lower margin, the vertical portable setting of frame is on the lower margin. The blocking mechanism is arranged at the pushing end of the unpowered labor-saving line edge mechanism, can push the material rack in from the pushing end and pull the material rack out from the pushing end, can adjust the height and the position to adapt to various occasions, has the advantages of ingenious design, simple structure, simple and convenient manufacture and low cost, and is suitable for large-scale popularization and application.

Description

Blocking mechanism

Technical Field

The invention relates to the technical field of logistics equipment, in particular to the technical field of electromechanical automatic logistics equipment, and specifically relates to a blocking mechanism.

Background

The logistics storage industry has been developed vigorously in China in recent years, and due to the continuous progress of technology and capability of the manufacturing industry and the further increase of requirements at home and abroad, higher requirements are put forward on logistics storage and the distribution capability of local materials or parts. The traditional manpower-intensive logistics mode cannot meet the modern logistics requirements of various types, large differences in shapes and weights and increasing efficiency requirements at present.

In order to meet the demand of modern logistics, a lot of automatic warehouse and handling devices, such as an automatic stereoscopic warehouse, a stacker, a gripping robot, a conveying device, an AGV (automated guided Vehicle), and the like, have been used in the industry. However, in some special logistics and parts logistics handling fields, the prior art still has certain limitations.

For example, the chinese utility model patent "an E-frame automatic wiring system" (patent No. ZL201420109121.5) discloses the following: an AGV simultaneously pulls a plurality of E-type vehicles to accurately stop, can push a material rack on an E-type frame for placing various articles such as goods or material boxes to be carried out to a powerless side roller line aligned with the frame, or can pull the material rack on the powerless side roller line aligned with the frame back to the frame, and then can pull an on-line system to other specified stations through the AGV and the like to automatically go on and off the line of the material rack; the system improves the utilization rate and the working efficiency of the operation space, and reduces the cost of installing power and control equipment at the operation station. The unpowered line side roller line mentioned in the patent is mostly fixed on the ground through four ground feet, and the unpowered line side roller line is inclined inwards by adjusting the height difference of the front ground foot and the rear ground foot, so that a material rack pushed onto the unpowered line side roller line cannot slide off from a pushing-in end; but at the artifical in-process of getting the material, especially people stand and get the material on the work or material rest, hardly guarantee that the work or material rest can not follow the end landing of pushing in, have the potential safety hazard.

At present, a one-way blocking device similar to that shown in fig. 1 is arranged on a power-free labor-saving line edge mechanism similar to a power-free roller line, the one-way blocking device generally comprises a turning plate 1, a turning plate fixing seat 2, a turning plate rotating shaft 3 and a torsion spring 4, the turning plate rotating shaft 3 is transversely arranged on the turning plate fixing seat 2, the turning plate 1 is vertically arranged and can be rotatably arranged on the turning plate rotating shaft 3 backwards (along the direction of an acting force F shown by an arrow in the figure), the turning plate 1 cannot rotate forwards, and the torsion spring 4 is sleeved on the turning plate rotating shaft 3 and respectively abuts against the turning plate 1 and the turning plate rotating shaft 3 to tend to enable the turning plate. When the automatic turnover mechanism is used, the turnover plate fixing seat 2 is fixed at the pushing-in end of the unpowered labor-saving line edge mechanism, the front of the turnover plate fixing seat faces outwards, when the material rack is pushed into the unpowered labor-saving line edge mechanism from the pushing-in end, the turnover plate 1 is pushed backwards along the direction of an acting force F shown by an arrow in the figure, the turnover plate 1 rotates backwards until the material rack is pushed into the unpowered labor-saving line edge mechanism, and the turnover plate 1 rotates forwards under the action of the torsion spring 4 until the turnover plate returns to the vertical position.

However, the one-way blocking device can only push the material rack into the material rack from the pushing end but cannot pull the material rack out of the pushing end, and the material rack can only be pulled out of other ports because the one-way blocking device blocks the material rack from being pulled out of the pushing end, so that the use is inconvenient; and the device must be fixed on a powerless labor-saving line edge mechanism, and the height and the position cannot be adjusted.

Therefore, a blocking mechanism is needed to be provided, which is installed at the pushing end of the unpowered labor-saving linear edge mechanism, can push the material rack in from the pushing end and can also pull out from the pushing end, and is convenient to use; preferably, the height and position can also be adjusted to accommodate a variety of situations.

Disclosure of Invention

In order to overcome the disadvantages in the prior art, an object of the present invention is to provide a blocking mechanism, which is installed at the pushing end of the unpowered labor-saving edge mechanism and can push the rack in from the pushing end and pull the rack out from the pushing end, and which is suitable for large-scale popularization and application.

Another object of the present invention is to provide a blocking mechanism, which can adjust the height and position to suit various occasions, and is suitable for large-scale popularization and application.

Another objective of the present invention is to provide a blocking mechanism, which has smart design, simple structure, easy manufacture, low cost, and is suitable for large-scale popularization and application.

In order to achieve the above object, the present invention provides a blocking mechanism, which is characterized by comprising a frame, a driving device and a crank assembly, wherein the crank assembly comprises a crank, a curved bar, a guide rail and a blocking piece, the guide rail is vertically movably arranged on the frame, the blocking piece is arranged at the upper end of the guide rail and protrudes out of the frame, the upper end of the curved bar is rotatably connected with the lower end of the guide rail, the driving device is connected with one end of the crank for driving the crank to rotate, and the other end of the crank is rotatably connected with the lower end of the curved bar.

Preferably, the crank assembly further comprises a needle bearing set located between and respectively connecting the guide rail and the frame such that the guide rail is vertically movably disposed on the frame through the needle bearing set.

Preferably, the blocking mechanism further comprises a drive shaft rotatably disposed on the frame, the crank being disposed at one end on the drive shaft, and the drive means being coupled to the drive shaft for driving the drive shaft in rotation.

Preferably, the blocking mechanism further comprises a driving sprocket, a driven sprocket and a chain, the driven sprocket is disposed on the driving shaft, the driving device is connected with the driving sprocket for driving the driving sprocket to rotate, and the chain is wound on the driving sprocket and the driven sprocket.

Preferably, the crank assembly further comprises a crankshaft crank stop, the crank being located below and in line with the crankshaft, the crankshaft and the crank being arranged at an angle, the crankshaft crank stop being located below the crankshaft and the crank.

Preferably, the crank assembly further comprises a crankshaft crank stop, the crank being located below the crankshaft and aligned with the crankshaft, the crankshaft and the crank being vertically disposed, the crankshaft crank stop being located on one side of the crankshaft and the crank.

Preferably, the number of the crank assemblies is two, the two crank assemblies are arranged horizontally at intervals, and the driving device is respectively connected with one ends of the cranks of the two crank assemblies and used for driving the cranks to rotate in the same direction.

Preferably, the stopping mechanism further includes a limiting device, the limiting device includes a first limiting member and a second limiting member, a limiting long hole is provided in the first limiting member, one end of the first limiting member is rotatably connected to the guide rail, and the second limiting member is installed on the machine frame and is transversely inserted into the limiting long hole relative to the limiting long hole.

Preferably, the limiting device further includes a position detection device, the position detection device is disposed on the second limiting member and is matched with the limiting long hole to detect whether the second limiting member contacts one of two ends of the limiting long hole, and the position detection device is further in signal connection with the driving device and is used for sending a signal to the driving device when detecting that the second limiting member contacts the one of the two ends, so as to control the driving device to stop working.

Preferably, the blocking mechanism further comprises a ground foot, and the rack is vertically movably arranged on the ground foot.

The invention has the following beneficial effects:

1. the blocking mechanism comprises a rack, a driving device and a crank component, wherein the crank component comprises a crank, a curved rod, a guide rail and a blocking piece, the guide rail is vertically and movably arranged on the rack, the blocking piece is arranged at the upper end of the guide rail and protrudes out of the rack, the upper end of the curved rod is rotatably connected with the lower end of the guide rail, the driving device is connected with one end of the crank and is used for driving the crank to rotate, the other end of the crank is rotatably connected with the lower end of the curved rod, so that the guide rail and the blocking piece at the upper end of the guide rail are pushed to move upwards or the guide rail and the blocking piece at the upper end of the guide rail are pulled to move downwards through the curved rod by virtue of the rotation or the reverse rotation of the crank, when the blocking mechanism is arranged at the pushing end of the unpowered labor-saving linear edge mechanism, the blocking piece moves downwards, therefore, the material frame can be pushed in from the pushing end and pulled out from the pushing end after being installed at the pushing end of the unpowered labor-saving line edge mechanism, and the material frame pushing device is suitable for large-scale popularization and application.

2. The blocking mechanism further comprises the anchor feet, and the rack is vertically movably arranged on the anchor feet, so that the height and the position of the rack can be adjusted through the anchor feet, and the height and the position of the blocking piece can be adjusted, therefore, the height and the position of the blocking piece can be adjusted to adapt to various occasions, and the blocking mechanism is suitable for large-scale popularization and application.

3. The blocking mechanism comprises a rack, a driving device and a crank component, wherein the crank component comprises a crank, a curved rod, a guide rail and a blocking piece, the guide rail is vertically and movably arranged on the rack, the blocking piece is arranged at the upper end of the guide rail and protrudes out of the rack, the upper end of the curved rod is rotatably connected with the lower end of the guide rail, the driving device is connected with one end of the crank and is used for driving the crank to rotate, the other end of the crank is rotatably connected with the lower end of the curved rod, so that the guide rail and the blocking piece at the upper end of the guide rail are pushed to move upwards or the guide rail and the blocking piece at the upper end of the guide rail are pulled to move downwards through the curved rod by virtue of the rotation or the reverse rotation of the crank, when the blocking mechanism is arranged at the pushing end of the unpowered labor-saving linear edge mechanism, the blocking piece moves downwards, therefore, the novel LED lamp is ingenious in design, simple in structure, simple and convenient to manufacture, low in cost and suitable for large-scale popularization and application.

These and other objects, features and advantages of the present invention will become more fully apparent from the following detailed description, the accompanying drawings and the appended claims, wherein like reference numerals refer to like parts throughout the several views, and wherein like reference numerals refer to like parts throughout the several views.

Drawings

Fig. 1 is a perspective view of a conventional one-way blocking device.

FIG. 2 is a perspective view of an embodiment of the blocking mechanism of the present invention.

Fig. 3 is a partially enlarged schematic view of the structure shown in fig. 2.

Fig. 4 is a schematic top view of the embodiment shown in fig. 2.

(symbol description)

1, turning a plate; 2, turning plate fixing seats; 3, turning plate rotating shafts; 4 a torsion spring; 5, a frame; 6, a driving device; 7 a crank assembly; 71 a crank; 72 a curved rod; 73 a guide rail; 74 a stopper; 75 crank stop; 8 driving the shaft; 9 a drive sprocket; 10, a driven sprocket; 11, a chain; 12, a limiting device; 13 a first stopper; 14 a second limiting member; 15 limiting long holes; 16 feet.

Detailed Description

In order to clearly understand the technical contents of the present invention, the following examples are given in detail.

Referring to fig. 2 to 4, in an embodiment of the present invention, the blocking mechanism of the present invention includes a frame 5, a driving device 6, and a crank assembly 7, where the crank assembly 7 includes a crank 71, a curved rod 72, a guide rail 73, and a blocking member 74, the guide rail 73 is vertically movably disposed on the frame 5, the blocking member 74 is disposed at an upper end of the guide rail 73 and protrudes from the frame 5, an upper end of the curved rod 72 is rotatably connected to a lower end of the guide rail 73, the driving device 6 is connected to one end of the crank 71 for driving the crank 71 to rotate, and another end of the crank 71 is rotatably connected to a lower end of the curved rod 72.

The guide rail 73 is vertically movably disposed on the frame 5 by any suitable structure, and in an embodiment of the present invention, the crank assembly 7 further includes a needle bearing set (not shown) disposed between the guide rail 73 and the frame 5 and respectively connecting the guide rail 73 and the frame 5, so that the guide rail 73 is vertically movably disposed on the frame 5 through the needle bearing set.

The end of the driving device 6 connected to the crank 71 may be of any suitable structure, as shown in fig. 2 and 4, in an embodiment of the present invention, the blocking mechanism further includes a driving shaft 8, the driving shaft 8 is rotatably disposed on the frame 5, one end of the crank 71 is disposed on the driving shaft 8, and the driving device 6 is connected to the driving shaft 8 for driving the driving shaft 8 to rotate.

The driving device 6 may be connected to the driving shaft 8 by any suitable structure, and referring to fig. 4, in an embodiment of the present invention, the blocking mechanism further includes a driving sprocket 9, a driven sprocket 10 and a chain 11, the driven sprocket 10 is disposed on the driving shaft 8, the driving device 6 is connected to the driving sprocket 9 for driving the driving sprocket 9 to rotate, and the chain 11 is wound on the driving sprocket 9 and the driven sprocket 10.

The driving device 6 may be connected to the driving sprocket 9 by any suitable structure, and in an embodiment of the present invention, the blocking mechanism further comprises a speed reducer (not shown), and the driving device 6 is connected to the driving sprocket 9 through the speed reducer.

The driving device 6 may be disposed on the frame 5, or may not be disposed on the frame 5, please refer to fig. 2 and 4, in an embodiment of the present invention, the driving device 6 is disposed on the frame 5.

The drive means 6 may be any suitable drive means, and in a particular embodiment of the invention, the drive means 6 is a motor.

The blocking member 74 may have any suitable shape, and referring to fig. 2-4, in one embodiment of the present invention, the blocking member 74 is a blocking piece.

In order to make the blocking mechanism of the present invention work more reliably, referring to fig. 2 and 4, in an embodiment of the present invention, the crank assembly 7 further includes a crank rod and crank blocking member 75, the crank 71 is located below the crank 72 and is aligned with the crank 72, the crank 72 and the crank 71 are disposed obliquely, and the crank rod and crank blocking member 75 is located below the crank 72 and the crank 71. With this arrangement, when the crank 71 is positioned under the curved bar 72 and in line with the curved bar 72, the guide 73 is pushed up to the highest point by the curved bar 72, the stopper 74 reaches the highest point, and when the crank 71 continues to rotate downward beyond the dead point, it is stopped by the curved bar crank stopper 75, and the crank 71 cannot continue to rotate downward by the driving device 6 or gravity, and the position of the stopper 74 does not change no matter how much force is applied to the stopper 74. That is, the crankshaft crank stop 75 is primarily used to stop the movement of the crankshaft 72 and the crank 71.

Obviously, the crankshaft 72 and the crank 71 may also be arranged vertically, in which case the crankshaft crank stop 75 is located on one side of the crankshaft 72 and the crank 71. With this arrangement, when the crank 71 is located under the curved bar 72 and in line with the curved bar 72, the guide rail 73 is pushed up to the highest point by the curved bar 72, the stopper 74 reaches the highest point, and when the crank 71 continues to rotate downward toward the curved bar crank stopper 75 side beyond the dead point, the crank 71 is stopped by the curved bar crank stopper 75, and the crank 71 cannot continue to rotate downward by the driving device 6 or gravity, and the position of the stopper 74 does not change no matter how much force is applied to the stopper 74.

The crankshaft crank stop 75 may have any suitable shape, and referring to fig. 2 and 4, in one embodiment of the present invention, the crankshaft crank stop 75 is a crankshaft crank stop plate.

In order to make the blocking mechanism of the present invention work more reliably, preferably, the number of the crank assemblies 7 is two, two sets of the crank assemblies 7 are arranged at relatively horizontal intervals, and the driving device 6 is respectively connected with one end of the crank 71 of each of the two sets of the crank assemblies 7 for driving the crank 71 to rotate in the same direction. Referring to fig. 4, in an embodiment of the present invention, in the case that the blocking mechanism further includes a driving shaft 8, one end of the crank 71 of each of the two crank assemblies 7 is mounted on the driving shaft 8.

In order to prevent the blocking member 74 from rising too high or falling too low, please refer to fig. 2 to 4, in an embodiment of the present invention, the blocking mechanism further includes a limiting device 12, the limiting device 12 includes a first limiting member 13 and a second limiting member 14, a limiting long hole 15 is disposed in the first limiting member 13, one end of the first limiting member 13 is rotatably connected to the guide rail 73, and the second limiting member 14 is disposed on the frame 5 and is transversely inserted into the limiting long hole 15 relative to the limiting long hole 15. Therefore, in the process of moving the guide rail 73 upward, the blocking member 74 and the first limiting member 13 are driven to move upward, the second limiting member 14 gradually approaches the lower end of the limiting long hole 15 or the end part of one end far away from the first limiting member 13 until the two contact, and the blocking member 74 reaches the upper limit point and cannot move upward any more; in the process that the guide rail 73 moves downwards, the blocking member 74 and the first limiting member 13 are driven to move downwards, the second limiting member 14 gradually approaches the upper end of the limiting long hole 15 or the end portion close to one end of the first limiting member 13 until the two contact, and the blocking member 74 reaches the lower limit point and cannot move downwards any more. That is, the limiting device 12 is used for limiting the vertical moving stroke of the guide rail 73.

In order to control the driving device 6 to stop working when the blocking member 74 reaches the upper limit position and the lower limit position, in an embodiment of the present invention, the limiting device 12 further includes a position detecting device (not shown in the figure), the position detecting device is disposed on the second limiting member 14 and is disposed in cooperation with the limiting long hole 15 for detecting whether the second limiting member 14 contacts one of two ends of the limiting long hole 15, and the position detecting device is further connected to the driving device 6 for sending a signal to the driving device 6 to control the driving device 6 to stop working when detecting that the second limiting member 14 contacts the one end. The position detection means may be, for example, two microswitches.

In order to adjust the height and position of the blocking member 74, referring to fig. 2 and 4, in an embodiment of the present invention, the blocking mechanism further includes a foot 16, and the frame 5 is vertically movably disposed on the foot 16. The ground feet 16 are used for fixing on the ground.

The movement process of the present invention will now be described in detail as follows:

before the crank 71 and the crank 72 are aligned, the crank 71 is driven by the driving device 6 to rotate counterclockwise (when viewed in fig. 2), the guide rail 73 is pushed to move upward via the crank 72, the blocking member 74 is raised to a desired position (if the position limiting device 12 is present, the blocking member 74 is raised to an upper limit position point), and the driving device 6 can be stopped (if the position limiting device 12 further includes a position detecting device, the driving device 6 is controlled by the position detecting device to stop working).

When the crank 71 and the crank 72 are in line, the blocking member 74 is raised to the highest position, and the driving device 6 continues to drive the crank 71 to rotate downward or the crank 71 continues to rotate downward under the action of gravity beyond the dead point, and the crank 71 is blocked by the crank-crank blocking member 75, so that the crank 71 cannot rotate downward any more, and the position of the blocking member 74 does not change no matter how much force is applied to the blocking member 74.

When the driving device 6 drives the crank 71 to rotate reversely (rotate clockwise) to help the crank 71 rotate upwards to cross the dead point, the guide rail 73 is pulled to move downwards via the crank 72, the blocking member 74 descends to the lower desired position (if the position limiting device 12 is present, the blocking member 74 descends to the lower limit point), and the driving device 6 can be stopped (if the position limiting device 12 further comprises a position detecting device, the driving device 6 is controlled to stop working through the position detecting device).

When the crank 71 and the crank 72 overlap, the stopper 74 descends to the lowest position.

When the device is used, the ground feet 16 are fixed on the ground at the pushing-in end side of the unpowered labor-saving line side mechanism, the height and the position of the rack 5 are adjusted according to the height of the pushing-in end of the unpowered labor-saving line side mechanism, when the material rack needs to be pushed into the unpowered labor-saving line side mechanism, the blocking piece 74 is lowered, the material rack can be pushed in from the pushing-in end of the unpowered labor-saving line side mechanism, after the material rack is pushed into the unpowered labor-saving line side mechanism, the blocking piece 74 is lifted, the material rack can be prevented from slipping from the pushing-in end of the unpowered labor-saving line side mechanism, when the material rack needs to be pulled out, the blocking piece 74 is lowered, and the material rack can be pulled out from the pushing.

Therefore, by adopting the invention, the blocking piece can effectively block the material rack from sliding off, thereby improving the safety and the convenience of use; the height and the position of the rack and the blocking piece on the rack are adjustable, and the machine is suitable for any of various line edge mechanisms; the lifting type blocking piece enables any port of the material rack to be free from influence when the material rack enters or exits; and a limiting device is adopted, a mechanical mechanism is used for self-locking, and the safety performance is high.

In conclusion, the blocking mechanism disclosed by the invention can push the material rack into the pushing end of the unpowered labor-saving line edge mechanism and pull the material rack out of the pushing end after being installed at the pushing end of the unpowered labor-saving line edge mechanism, can adjust the height and the position to adapt to various occasions, is ingenious in design, simple in structure, simple and convenient to manufacture, low in cost and suitable for large-scale popularization and application.

It will thus be seen that the objects of the invention have been fully and effectively accomplished. While the functional and structural principles of this invention have been shown and described in detail in the embodiments, it will be understood by those skilled in the art that the embodiments of the invention described above and illustrated in the drawings are merely exemplary and are not limiting of the invention, which can be modified in any manner without departing from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the claims.

Claims

1. The blocking mechanism is characterized by comprising a rack, a driving device and a crank assembly, wherein the crank assembly comprises a crank, a crank rod, a guide rail and a blocking piece, the guide rail is vertically movably arranged on the rack, the blocking piece is arranged at the upper end of the guide rail and protrudes out of the rack, the upper end of the crank rod is rotatably connected with the lower end of the guide rail, the driving device is connected with one end of the crank and used for driving the crank to rotate, and the other end of the crank is rotatably connected with the lower end of the crank rod.

2. The barrier mechanism of claim 1, wherein the crank assembly further comprises a needle bearing set positioned between and connecting the guide rail and the frame, respectively, such that the guide rail is vertically movably disposed on the frame by the needle bearing set.

3. A blocking mechanism according to claim 1, further comprising a drive shaft rotatably disposed on the frame, the crank being disposed at one end on the drive shaft, the drive means being connected to the drive shaft for driving rotation of the drive shaft.

4. The blocking mechanism of claim 3, further comprising a drive sprocket, a driven sprocket disposed on the drive shaft, and a chain wound around the drive sprocket and the driven sprocket, wherein the drive device connects the drive sprocket for driving the drive sprocket in rotation.

5. The blocking mechanism of claim 1, wherein said crank assembly further comprises a bell crank blocking member, said crank being positioned below said bell crank and in line with said bell crank, said bell crank and said crank being angularly disposed, said bell crank blocking member being positioned below said bell crank and said crank.

6. The blocking mechanism of claim 1, wherein said crank assembly further comprises a bell crank blocking member, said crank being positioned below and in line with said bell crank, said bell crank and said crank being vertically disposed, said bell crank blocking member being positioned to one side of said bell crank and said crank.

7. The blocking mechanism as claimed in claim 1 wherein there are two sets of said crank assemblies, said two sets of said crank assemblies being horizontally spaced apart from one another, said drive means being connected to one end of each of said cranks of said two sets of said crank assemblies for driving said cranks to rotate in the same direction.

8. The stop mechanism according to claim 1, further comprising a stop device, wherein the stop device comprises a first stop member and a second stop member, the first stop member has a long stop hole therein, one end of the first stop member is rotatably connected to the guide rail, and the second stop member is mounted on the frame and is transversely inserted into the long stop hole with respect to the long stop hole.

9. The stopping mechanism according to claim 8, wherein the position limiting device further comprises a position detecting device disposed on the second limiting member and configured to cooperate with the long limiting hole to detect whether the second limiting member contacts one of the two ends of the long limiting hole, and the position detecting device is further in signal connection with the driving device to send a signal to the driving device to control the driving device to stop working when detecting that the second limiting member contacts the one of the two ends.

10. The blocking mechanism of claim 1, further comprising a foot, wherein the frame is vertically movably disposed on the foot.