CN221109286U - Surface cleaning device - Google Patents

Abstract

The present application relates to a surface cleaning apparatus comprising: cleaning the pressing plate; the alcohol spray pipe is positioned at one side of the cleaning pressing plate; the carrying platforms are arranged below the cleaning pressing plate at intervals; dust-free cloth; the winding and unwinding mechanism is used for winding and unwinding the dust-free cloth, so that the dust-free cloth passes through the interval between the cleaning pressing plate and the carrying platform below the alcohol spray pipe in sequence; the vertical driving mechanism is used for driving the cleaning pressing plate to move along the vertical direction; the pressure driving mechanism is used for providing pressure in the vertical direction for the cleaning pressing plate; the circumference driving mechanism is used for driving the cleaning pressing plate to do plane circumference motion; and the horizontal driving mechanism is used for driving the carrying platform to horizontally and transversely move. The surface cleaning device can improve the cleaning capability and remove the glue foreign matters on the glass cover plate.

Description

Surface cleaning device

Technical Field

The application relates to the technical field of surface cleaning, in particular to a surface cleaning device for cleaning display screen glass.

Background

The glass cover plate is stuck on the display screen, the glass cover plate needs to be cleaned before sticking to ensure the quality of the screen, the dust-free cloth is used for wiping after the dust-free cloth is sprayed by alcohol, because the manual wiping efficiency is too low, automatic wiping equipment appears on the market at present, the dust-free cloth is contacted with the surface by pushing down the alcohol track of the dust-free cloth by using an adhesive tape with the width of about 5mm after spraying a linear alcohol track on the dust-free cloth, the surface is placed on a moving platform, the moving platform is driven to do linear reciprocating motion to realize the action of wiping the surface by the dust-free cloth, the cleaning mode of the linear reciprocating wiping is suitable for products with relatively clean surfaces and is used for removing floating particles on the surfaces, but for the glass cover plate recovered from defective products, glue foreign matters remain on the glass cover plate and are difficult to remove.

Disclosure of utility model

Based on this, it is necessary to provide a surface cleaning apparatus capable of improving cleaning ability to remove the glue-like foreign matters on the glass cover plate.

In order to achieve the above purpose, the application adopts the following technical scheme:

A surface cleaning apparatus comprising: cleaning the pressing plate; the alcohol spray pipe is positioned at one side of the cleaning pressing plate; the carrying platforms are arranged below the cleaning pressing plate at intervals; dust-free cloth; the winding and unwinding mechanism is used for winding and unwinding the dust-free cloth, so that the dust-free cloth passes through the interval between the cleaning pressing plate and the carrying platform below the alcohol spray pipe in sequence; the vertical driving mechanism is used for driving the cleaning pressing plate to move along the vertical direction; the pressure driving mechanism is used for providing pressure in the vertical direction for the cleaning pressing plate; the circumference driving mechanism is used for driving the cleaning pressing plate to do plane circumference motion; and the horizontal driving mechanism is used for driving the carrying platform to horizontally and transversely move.

Further, circumference actuating mechanism includes first mounting panel, motor and eccentric shaft, first mounting panel connect in pressure actuating mechanism's drive end, the motor is installed on the first mounting panel be equipped with the circular slot on the washing clamp plate, the washing clamp plate is located first mounting panel below and set up in through the symmetry two horizontal and vertical slip subassembly of circular slot both sides connect first mounting panel, eccentric shaft one end fixed connection the drive end of motor, the other end inserts the circular slot.

Further, a plurality of tension springs are connected between the first mounting plate and the cleaning platen.

Further, the pressure driving mechanism comprises a second mounting plate, an air cylinder and a plurality of first guide assemblies, wherein the second mounting plate is connected to the driving end of the vertical driving mechanism, the air cylinder is mounted on the second mounting plate, and the driving end of the air cylinder is connected with the first mounting plate; the first guide assembly comprises a first sleeve seat and a first guide rod which are vertically arranged, the first sleeve seat is fixedly arranged on the second mounting plate, and the first guide rod is slidably sleeved on the first sleeve seat and one end of the first guide rod is fixedly connected with the first mounting plate.

Further, vertical actuating mechanism includes first straight line module, backup pad and a plurality of second direction subassembly, the drive end of first straight line module is connected the backup pad, second direction subassembly includes the second sleeve seat and the second guide arm of vertical setting, the fixed setting of relative frame of second sleeve seat, second guide arm slip cap is located on the second sleeve seat, the one end fixed connection of second guide arm the second mounting panel, the other end fixed connection the backup pad.

Further, still including being used for right the stroke of first straight line module carries out spacing first spacing response subassembly, first spacing response subassembly includes first zero point photoelectric switch, goes up limit photoelectric switch, lower limit photoelectric switch and first separation blade, first zero point photoelectric switch go up limit photoelectric switch lower limit photoelectric switch is all fixed relative to the frame, and in vertical direction interval setting, first separation blade sets up in the backup pad.

Further, the horizontal driving mechanism comprises a second linear module and a third guiding assembly, the driving end of the second linear module is connected with the carrying platform, the third guiding assembly comprises a guide rail and a sliding block, the guide rail is fixed relative to the machine base and horizontally and transversely arranged, the sliding block is slidably mounted on the guide rail, and the sliding block is fixedly connected with the carrying platform.

Further, the device further comprises a second limit sensing assembly for limiting the travel of the second linear module, the second limit sensing assembly comprises a second zero photoelectric switch, a left limit photoelectric switch, a right limit photoelectric switch and a second baffle, the second zero photoelectric switch, the left limit photoelectric switch and the right limit photoelectric switch are fixed relative to the machine base, the second zero photoelectric switch, the left limit photoelectric switch, the right limit photoelectric switch and the second baffle are arranged on the carrying platform at intervals in the horizontal transverse direction.

When the surface cleaning device is used, the glass cover plate is firstly placed on the carrying platform, then the alcohol spray pipe sprays alcohol on the dust-free cloth, the winding and unwinding mechanism simultaneously winds and unwinds the dust-free cloth for a period of time until the dust-free cloth positioned under the coverage range of the cleaning pressing plate is sprayed with alcohol, then the horizontal driving mechanism is started to move the carrying platform below the cleaning pressing plate, then the vertical driving mechanism is started to move the cleaning pressing plate downwards to paste the dust-free cloth on the glass cover plate, then the pressure driving mechanism is started to press the cleaning pressing plate to the glass cover plate under a certain pressure, and meanwhile the circumferential driving mechanism is started to enable the cleaning pressing plate to do planar circumferential movement and the horizontal driving mechanism is started to enable the carrying platform to horizontally and transversely move. So, through the plane circular motion who washs the clamp plate to glass apron carries out the wiping of circumference grinding type, guarantees to clean whole glass apron's surface through the horizontal lateral shifting of year thing platform to promote clean ability, with can get rid of the gluey class foreign matter on the glass apron.

Drawings

In order to more clearly illustrate the embodiments of the application or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of an embodiment of the present application;

FIG. 2 is a schematic view of a cleaning platen, a circumferential drive mechanism, and a pressure drive mechanism according to an embodiment of the present application;

Fig. 3 is a front view of fig. 2 in the direction of the arrow.

Reference numerals illustrate:

10. A carrying platform; 20. a horizontal driving mechanism; 21. a second linear module; 22. a third guide assembly; 221. a guide rail; 222. a slide block; 23. the second limit sensing assembly; 231. a second zero photoelectric switch; 232. a left limit photoelectric switch; 233. a right limit photoelectric switch; 234. a second baffle; 30. cleaning the pressing plate; 31. a circular groove; 32. a lateral and longitudinal sliding assembly; 321. a transverse slide rail; 322. a transverse slide block; 323. a connecting plate; 324. a longitudinal slide rail; 325. a longitudinal slide block; 33. tensioning a spring; 40. an alcohol spray pipe; 60. a circumferential drive mechanism; 61. a first mounting plate; 62. a motor; 63. an eccentric shaft; 70. a pressure driving mechanism; 71. a second mounting plate; 72. a cylinder; 73. a first guide assembly; 731. a first sleeve mount; 732. a first guide bar; 80. a vertical driving mechanism; 81. a first linear module; 82. a support plate; 83. a second guide assembly; 831. a second sleeve seat; 832. a second guide bar; 84. the first limit sensing assembly; 841. a first zero photoelectric switch; 842. an upper limit photoelectric switch; 843. a lower limit photoelectric switch; 844. a first baffle.

Detailed Description

In order that the above objects, features and advantages of the application will be readily understood, a more particular description of the application will be rendered by reference to the appended drawings. The present application may be embodied in many other forms than described herein and similarly modified by those skilled in the art without departing from the spirit of the application, so that the application is not limited to the specific embodiments disclosed below.

In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present application and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present application.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present application, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.

In the present application, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.

In the present application, unless expressly stated or limited otherwise, a first feature "up" or "down" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact via an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

Referring to fig. 1, the application provides a surface cleaning device, which comprises a stand, a stage component and a cleaning component, wherein the stage component and the cleaning component are arranged on the stand.

The object stage component comprises an object carrying platform 10 and a horizontal driving mechanism 20, wherein the object carrying platform 10 is used for placing a glass cover plate to be cleaned, and the horizontal driving mechanism 20 is used for driving the object carrying platform 10 to horizontally and transversely move.

The cleaning component comprises a cleaning pressing plate 30, an alcohol spraying pipe 40, dust-free cloth (not shown in the figure), a winding and unwinding mechanism (not shown in the figure), a circumference driving mechanism 60, a pressure driving mechanism 70 and a vertical driving mechanism 80, wherein the cleaning pressing plate 30 is arranged above the carrying platform 10 at intervals, the alcohol spraying pipe 40 is positioned on one side of the cleaning pressing plate 30 and is used for spraying alcohol on the dust-free cloth, the winding and unwinding mechanism is used for winding and unwinding the dust-free cloth, so that the dust-free cloth sequentially passes through the interval between the cleaning pressing plate 30 and the carrying platform 10 below the alcohol spraying pipe 40, the circumference driving mechanism 60 is used for driving the cleaning pressing plate 30 to perform plane circular motion, the pressure driving mechanism 70 is used for applying a vertical downward thrust to the cleaning pressing plate 30, and the vertical driving mechanism 80 is used for driving the cleaning pressing plate 30 to move along the vertical direction so as to be close to or far away from the carrying platform 10.

When the technical scheme is used, the glass cover plate is firstly placed on the carrying platform 10, then the alcohol spray pipe 40 sprays alcohol on the dust-free cloth, meanwhile, the winding and unwinding mechanism winds and unwinds the dust-free cloth for a period of time until the dust-free cloth positioned under the coverage range of the cleaning press plate 30 is sprayed with alcohol, then the horizontal driving mechanism 20 is started, the carrying platform 10 is moved below the cleaning press plate 30, then the vertical driving mechanism 80 is started, the cleaning press plate 30 is moved downwards to attach the dust-free cloth on the glass cover plate, then the pressure driving mechanism 70 is started to press the cleaning press plate 30 to the glass cover plate under a certain pressure, and meanwhile, the circumferential driving mechanism 60 is started to enable the cleaning press plate 30 to do plane circular motion and the horizontal driving mechanism 20 is started to enable the carrying platform 10 to horizontally and transversely move. In this way, the glass cover plate is wiped in a circumferential grinding mode through the planar circular motion of the cleaning pressing plate 30, and the surface of the whole glass cover plate is ensured to be cleaned through the horizontal transverse movement of the carrying platform 10, so that the cleaning capacity is improved, and the glue foreign matters on the glass cover plate can be removed.

In this embodiment, specifically, the cleaning platen 30 is rectangular, and the length and width of the cleaning platen 30 and the length and width of the dust-free cloth sprayed with alcohol are close to the length and width of the carrying platform 10, so that the whole surface of the glass cover plate can be cleaned, and the cleaning efficiency can be improved.

In this embodiment, the carrying platform 10 adopts a vacuum adsorption platform, so that the glass cover plate can be adsorbed and fixed, and the glass cover plate is prevented from moving.

The winding and unwinding mechanism is used for winding and unwinding and traction of dust-free cloth, and can be realized by adopting the existing material roller mechanism, and details are omitted here.

Referring to fig. 2, in the present embodiment, the circumferential driving mechanism 60 includes a first mounting plate 61, a motor 62 and an eccentric shaft 63, the first mounting plate 61 is connected to the driving end of the pressure driving mechanism 70, the motor 62 is mounted on the first mounting plate 61, a circular groove 31 is formed on the cleaning platen 30, the cleaning platen 30 is located below the first mounting plate 61 and is connected to the first mounting plate 61 through two horizontal and vertical sliding assemblies 32 symmetrically disposed on two sides of the circular groove 31, one end of the eccentric shaft 63 is fixedly connected to the driving end of the motor 62, and the other end is inserted into the circular groove 31.

Specifically, referring to fig. 3, the lateral sliding component 32 includes a lateral sliding rail 321, a lateral sliding block 322222, a connecting plate 323, a longitudinal sliding rail 324 and a longitudinal sliding block 325222, the longitudinal sliding rail 324 is disposed on the first mounting plate 61, the longitudinal sliding block 325 is disposed at an upper end of the connecting plate 323 and is slidably mounted on the longitudinal sliding rail 324, the lateral sliding rail 321 is disposed at a lower end of the connecting plate 323, and the lateral sliding block 322 is disposed on the cleaning platen 30 and is slidably mounted on the lateral sliding rail 321.

It will be appreciated that by connecting the cleaning platen 30 to the first mounting plate 61 via the lateral and longitudinal slide assembly 32, the cleaning platen 30 can be translated relative to the first mounting plate 61 along a planar circumferential path as the motor 62 drives the eccentric shaft 63 to rotate, thereby effecting wiping of the glass cover plate in a circumferential abrasive form.

Further, a plurality of tensioning springs 33 are connected between the first mounting plate 61 and the cleaning press plate 30, and the tensioning springs 33 are used for reducing the weight of the cleaning press plate 30 and guaranteeing the connection stability of the cleaning press plate 30.

Referring to fig. 2, in the present embodiment, the pressure driving mechanism 70 includes a second mounting plate 71, a cylinder 72, and a plurality of first guide assemblies 73, the second mounting plate 71 is connected to the driving end of the vertical driving mechanism 80, the cylinder 72 is mounted on the second mounting plate 71, and the driving end of the cylinder 72 is connected to the first mounting plate 61; the first guiding assembly 73 comprises a first sleeve seat 731 and a first guiding rod 732, the first sleeve seat 731 is fixedly arranged on the second mounting plate 71, and the first guiding rod 732 is slidably sleeved on the first sleeve seat 731 and one end of the first guiding rod 732 is fixedly connected with the first mounting plate 61.

Specifically, the second mounting plate 71 is located above the first mounting plate 61, the second mounting plate 71 is provided with a yielding hole for placing the motor 62 and the eccentric shaft 63 of the circumferential driving mechanism 60, the air cylinders 72 are provided with two and symmetrically arranged on two sides of the eccentric shaft 63, and the first guiding assemblies 73 are provided with four rectangular four corners.

It will be appreciated that the pushing force of the air cylinders 72 on the first mounting plate 61 indirectly gives the cleaning platen 30 a pushing force, and the two air cylinders 72 and the four first guide assemblies 73 ensure that the pushing force balance is stable.

Referring to fig. 1, in this embodiment, the vertical driving mechanism 80 includes a first linear module 81, a supporting plate 82 and a plurality of second guiding components 83, the driving end of the first linear module 81 is connected with the supporting plate 82, the second guiding components 83 include a second sleeve seat 831 and a second guiding rod 832 which are vertically arranged, the second sleeve seat 831 is fixedly arranged relative to the machine base, the second guiding rod 832 is slidably sleeved on the second sleeve seat 831, one end of the second guiding rod 832 is fixedly connected with the second mounting plate 71, and the other end is fixedly connected with the supporting plate 82.

Specifically, the first linear modules 81 are disposed below the carrying platform 10, and the second guiding assemblies 83 are disposed four and two-by-two symmetrically on two sides of the carrying platform 10 in the longitudinal direction.

It will be appreciated that under the connection of the plurality of guide assemblies, the first linear module 81 stably drives the second mounting plate 71 to move in the vertical direction, so as to finally drive the cleaning platen 30 to move in the vertical direction, and the cleaning platen 30 can be close to or far from the carrying platform 10.

Further, referring to fig. 1, the first linear module 81 is configured with a first limit sensing assembly 84 for limiting the stroke of the first linear module 81, the first limit sensing assembly 84 includes a first zero photoelectric switch 841, an upper limit photoelectric switch 842, a lower limit photoelectric switch 843, and a first stop 844, the first zero photoelectric switch 841, the upper limit photoelectric switch 842, and the lower limit photoelectric switch 843 are disposed on the base at intervals along the vertical direction, and are all communicatively connected to the motor of the first linear module 81, and the first stop 844 is disposed on the support plate 82. The first stop 844 passes through the photoelectric switches to generate corresponding limit signals, and the limit signals control the motor of the first linear module 81 to be turned off, so that the cleaning press plate 30 can be positioned at the zero position, the upper limit position and the lower limit position.

Referring to fig. 1, in the present embodiment, the horizontal driving mechanism 20 includes a second linear module 21 and a third guiding assembly 22, the driving end of the second linear module 21 is connected to the carrying platform 10, the third guiding assembly 22 includes a guide rail 221 and a slider 222, the guide rail 221 is fixed relative to the base and horizontally and transversely disposed, the slider 222 is slidably mounted on the guide rail 221, and the slider 222 is fixedly connected to the carrying platform 10.

Specifically, two third guide assemblies 22 are provided, and the two third guide assemblies 22 are symmetrically disposed on two sides of the second linear module 21 in the longitudinal direction.

Further, referring to fig. 1, the second linear module 21 is configured with a second limit sensing assembly 23 for limiting the travel of the second linear module 21, where the second limit sensing assembly 23 includes a second zero photoelectric switch 231, a left limit photoelectric switch 232, a right limit photoelectric switch 233, and a second blocking piece 234, the second zero photoelectric switch 231, the left limit photoelectric switch 232, and the right limit photoelectric switch 233 are disposed on the base along a horizontal and transverse interval, and are all communicatively connected to the motor of the second linear module 21, and the second blocking piece 234 is disposed on the carrying platform 10. The second blocking piece 234 generates corresponding limit signals through the photoelectric switches, and controls the motor of the second linear module 21 to be turned off through the limit signals, so that the object carrying platform 10 can be positioned at the zero position, the left limit position and the right limit position.

In general, the surface cleaning device of the application adopts the cleaning press plate 30 to perform circumferential translation to clean the glass cover plate, namely, the dust-free cloth plane grinds the glass cover plate, compared with the traditional cleaning mode of the adhesive tape reciprocating wiping, the cleaning capability is greatly improved, and the surface cleaning device is suitable for cleaning the surface with adhesive foreign matters on the surface.

The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The examples described above represent only a few embodiments of the present application and are not to be construed as limiting the claims. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the application, which are all within the scope of the application. Accordingly, the scope of protection of the present application is to be determined by the appended claims.

Claims (8)

1. A surface cleaning apparatus comprising:

Cleaning the pressing plate;

The alcohol spray pipe is positioned at one side of the cleaning pressing plate;

The carrying platforms are arranged below the cleaning pressing plate at intervals;

Dust-free cloth;

The winding and unwinding mechanism is used for winding and unwinding the dust-free cloth, so that the dust-free cloth passes through the interval between the cleaning pressing plate and the carrying platform below the alcohol spray pipe in sequence;

the vertical driving mechanism is used for driving the cleaning pressing plate to move along the vertical direction;

the pressure driving mechanism is used for providing pressure in the vertical direction for the cleaning pressing plate;

the circumference driving mechanism is used for driving the cleaning pressing plate to do plane circumference motion;

And the horizontal driving mechanism is used for driving the carrying platform to horizontally and transversely move.

2. The surface cleaning apparatus of claim 1, wherein the circumferential driving mechanism comprises a first mounting plate, a motor and an eccentric shaft, the first mounting plate is connected to the driving end of the pressure driving mechanism, the motor is mounted on the first mounting plate, a circular groove is formed in the cleaning pressing plate, the cleaning pressing plate is located below the first mounting plate and is connected with the first mounting plate through two transverse and longitudinal sliding assemblies symmetrically arranged on two sides of the circular groove, one end of the eccentric shaft is fixedly connected to the driving end of the motor, and the other end of the eccentric shaft is inserted into the circular groove.

3. The surface cleaning apparatus of claim 2 wherein a plurality of tension springs are connected between the first mounting plate and the wash platen.

4. The surface cleaning apparatus of claim 2 wherein the pressure drive mechanism comprises a second mounting plate, a cylinder and a plurality of first guide assemblies, the second mounting plate being connected to the drive end of the vertical drive mechanism, the cylinder being mounted on the second mounting plate, the drive end of the cylinder being connected to the first mounting plate; the first guide assembly comprises a first sleeve seat and a first guide rod which are vertically arranged, the first sleeve seat is fixedly arranged on the second mounting plate, and the first guide rod is slidably sleeved on the first sleeve seat and one end of the first guide rod is fixedly connected with the first mounting plate.

5. The surface cleaning apparatus of claim 4, wherein the vertical driving mechanism comprises a first linear module, a supporting plate and a plurality of second guiding assemblies, the driving end of the first linear module is connected with the supporting plate, the second guiding assemblies comprise a second sleeve seat and a second guiding rod which are vertically arranged, the second sleeve seat is fixedly arranged relative to the machine base, the second guiding rod is slidably sleeved on the second sleeve seat, one end of the second guiding rod is fixedly connected with the second mounting plate, and the other end of the second guiding rod is fixedly connected with the supporting plate.

6. The surface cleaning apparatus of claim 5, further comprising a first limit sensing assembly for limiting the travel of the first linear module, the first limit sensing assembly comprising a first zero photoelectric switch, an upper limit photoelectric switch, a lower limit photoelectric switch, and a first blocking piece, the first zero photoelectric switch, the upper limit photoelectric switch, and the lower limit photoelectric switch being fixed relative to the base and being disposed at intervals in a vertical direction, the first blocking piece being disposed on the support plate.

7. The surface cleaning apparatus of claim 1, wherein the horizontal drive mechanism comprises a second linear module and a third guide assembly, the drive end of the second linear module is connected to the carrying platform, the third guide assembly comprises a guide rail and a slide block, the guide rail is fixed relative to the base and horizontally and transversely arranged, the slide block is slidably mounted on the guide rail, and the slide block is fixedly connected to the carrying platform.

8. The surface cleaning apparatus of claim 7, further comprising a second limit sensing assembly for limiting the travel of the second linear module, the second limit sensing assembly comprising a second zero point photoelectric switch, a left limit photoelectric switch, a right limit photoelectric switch, and a second blocking piece, the second zero point photoelectric switch, the left limit photoelectric switch, and the right limit photoelectric switch being fixed relative to the base and being disposed at a horizontal lateral interval, the second blocking piece being disposed on the loading platform.