CN215345319U

CN215345319U - Electrical box device and electrical equipment

Info

Publication number: CN215345319U
Application number: CN202120591246.6U
Authority: CN
Inventors: 严峰
Original assignee: Wuxi Little Swan Electric Co Ltd
Current assignee: Wuxi Little Swan Electric Co Ltd
Priority date: 2021-03-23
Filing date: 2021-03-23
Publication date: 2021-12-28
Anticipated expiration: 2031-03-23

Abstract

The application provides an electric appliance box device and electric equipment, wherein the electric appliance box device comprises an electric appliance box and a circuit board, the electric appliance box comprises a waterproof side wall and a waterproof top wall arranged at the top of the waterproof side wall, and a waterproof mounting cavity is defined by the waterproof side wall and the waterproof top wall together; the circuit board is arranged in the waterproof mounting cavity and comprises a substrate and an electronic element arranged on the substrate, the substrate is connected with the electric appliance box, and the electronic element is arranged on the bottom side of the substrate, which is deviated from the waterproof top wall. The utility model provides an electrical apparatus box-packed putting, in the normal use process, electrical apparatus box-packed putting's top up, the bottom is down, is about to the installation of circuit board inversion, and the base plate is close to waterproof roof installation, under the external dimension's of not additionally increasing electrical apparatus box the condition for the base plate has bigger terrain clearance, and the waterproof performance of circuit board is better.

Description

Electrical box device and electrical equipment

Technical Field

The application relates to the technical field of electricity, especially, relate to an electrical apparatus box-packed putting and electrical equipment.

Background

Among the correlation technique, the electrical apparatus box includes base and lid, and the circuit board passes through the fix with screw on the base earlier, detains the lid in the base top again, and lid and base surround the circuit board in both enclose the space of establishing, and the base plays the effect of supporting and installation circuit board, and in addition, the electrical apparatus box passes through the base installation to other structurally on.

The electric box has poor waterproofness, and the possibility that external water splashes to the terminals, pins and other structures of the circuit board is high.

SUMMERY OF THE UTILITY MODEL

In view of this, it is desirable to provide an electrical box device and an electrical apparatus with better waterproof performance.

The embodiment of the application provides an electrical apparatus box device, includes:

the electric appliance box comprises a waterproof side wall and a waterproof top wall arranged at the top of the waterproof side wall, and the waterproof side wall and the waterproof top wall jointly define a waterproof mounting cavity;

the circuit board is arranged in the waterproof mounting cavity and comprises a substrate and an electronic element arranged on the substrate, the substrate is connected with the electrical box, and the electronic element is arranged on the bottom side of the substrate, which is deviated from the waterproof top wall.

In some embodiments, any of the electronic components do not extend beyond the bottom end surface of the waterproof side wall in the top-bottom direction of the electrical box device.

In some embodiments, the appliance casing is a one-piece, flame retardant injection molded part.

In some embodiments, the distance between the base plate and the bottom edge of the watertight side walls is greater than the distance between the base plate and the watertight top.

In some embodiments, the bottom side of the electrical box is provided with an opening for accessing the circuit board, the opening is communicated with the waterproof mounting cavity, and the electronic element is exposed to the bottom side of the electrical box.

In some embodiments, the watertight mounting chamber communicates with the outside only through the opening.

In some embodiments, the electrical box is provided with at least one elastic hook extending into the waterproof mounting cavity, and the elastic hook abuts against the bottom side edge of the substrate along the top-bottom direction of the electrical box device.

In some embodiments, the electrical enclosure has at least one protrusion protruding from a bottom surface of the waterproof top wall, and a screw passes through the base plate and is screwed into the protrusion to secure the base plate to the protrusion.

In some embodiments, the electrical box comprises a bottom plate and a box cover which are connected with each other, the waterproof side wall and the waterproof top wall are integral parts of the box cover, the bottom side of the box cover is open, and the bottom plate is arranged at the bottom side of the box cover and covers the open part of the box cover.

The embodiment of the application provides electrical equipment, including organism, control panel and the electrical apparatus box-packed putting of above-mentioned arbitrary embodiment, control panel set up in on the organism, control panel with circuit board electrical connection.

In some embodiments, the appliance device is a laundry treatment device.

In some embodiments, the body includes a box body and a top cover disposed on the top of the box body, the control panel has a receiving space for receiving the electrical box device, a bottom side of the receiving space is open to form an opening, and a portion around the opening of the control panel abuts against a top surface of the top cover.

In some embodiments, the appliance casing supports and is attached to the top side of the top cover.

In some embodiments, the rear portion of the top cover has a sunken platform, the sunken platform and the control panel both extend along the left-right direction of the top cover, the bottom end of the control panel abuts against the sunken platform, and the control panel protrudes from the top surface of the top cover.

Among the prior art, the ground clearance of base plate is less, and in the water liquid in the external environment passed through the butt joint department of base and lid easily got into the electrical apparatus box, water liquid contacted circuit board and terminal easily. In the related art, if the height of the base plate from the ground is to be increased, the thickness of the base needs to be increased, and thus, the size of the electrical box in the height direction is significantly increased. In some electrical equipment with a narrow installation space, the external dimension of the electrical box is limited, and if the external dimension of the electrical box becomes larger, the dimensions of other structures of the electrical equipment may also change, which causes changes in design reference dimensions, production molds and the like, and increases production cost.

The electrical apparatus box device of this application embodiment, in the normal use process, waterproof roof is up, and electrical apparatus box device's top is up promptly, and the bottom is down, is about to the circuit board and inverts the installation for the base plate is close to waterproof roof installation, under the external dimension's of not additionally increasing electrical apparatus box the condition, makes the base plate have bigger terrain clearance, makes the waterproof performance of circuit board better.

Drawings

Fig. 1 is an exploded schematic view of an electrical box device according to an embodiment of the present application;

FIG. 2 is a schematic view of the structure of FIG. 1 from another perspective;

FIG. 3 is a cross-sectional view of the structure shown in FIG. 2;

fig. 4 is a schematic structural view of a laundry treating apparatus according to an embodiment of the present application;

FIG. 5 is a schematic partially exploded view of the structure shown in FIG. 4;

FIG. 6 is a schematic view of the structure of FIG. 5 from another perspective;

FIG. 7 is a schematic view of the structure of FIG. 4 from another perspective;

FIG. 8 is a cross-sectional view taken along the line A-A in FIG. 7;

fig. 9 is a partially enlarged schematic view of a portion B in fig. 8.

The reference numbers describe the electrical box device 1; an electric appliance box 11; a waterproof mounting cavity 11 a; an opening 11 b; a waterproof top wall 111; a waterproof side wall 112; a wire passing hole 112 a; an elastic hook 113; a lug 114; the projections 115; a circuit board 12; a substrate 121; an electronic component 122; a screw 13; a machine body 2; a case 21; a top cover 22; a sink table 221; a door body 23; a control panel 3; the accommodating space 3 a; knob 31

Detailed Description

It should be noted that, in the present application, technical features in examples and embodiments may be combined with each other without conflict, and the detailed description in the specific embodiment should be understood as an explanation of the gist of the present application and should not be construed as an improper limitation to the present application.

In the description of the embodiments of the present application, the "up", "down", "left", "right", "front", "back" orientation or positional relationship is based on the orientation or positional relationship shown in fig. 4, it is to be understood that these orientation terms are merely for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be considered as limiting the present application.

Referring to fig. 1 to 3, the electrical box device 1 includes an electrical box 11 and a circuit board 12.

Referring to fig. 2 and 3, the electrical box 11 includes a waterproof sidewall 112 and a waterproof top wall 111 disposed on top of the waterproof sidewall 112, and the waterproof sidewall 112 and the waterproof top wall 111 together define a waterproof mounting cavity 11 a.

It should be noted that the waterproof top wall 111 means that, during use, water in the external environment does not penetrate through the waterproof top wall 111 and enter the waterproof installation cavity 11 a. It is understood that in some embodiments, the waterproof top wall 111 may be integrally formed in a waterproof structure, such that the waterproof top wall 111 is not permeable to water at any position. In other embodiments, depending on the usage scenario, the waterproof top wall 111 may also be a waterproof structure at a position where the waterproof top wall 111 may contact with outside water, and a hole design at a position where the waterproof top wall 111 may not contact with water.

Referring to fig. 3, the circuit board 12 is disposed in the waterproof mounting cavity 11 a.

Referring to fig. 1, fig. 2 and fig. 3, the circuit board 12 includes a substrate 121 and an electronic component 122 disposed on the substrate 121, the substrate 121 is connected to the electrical box 11, and the electronic component 122 is disposed on a bottom side of the substrate 121 away from the waterproof top wall 111, that is, the electronic component 122 and the waterproof top wall 111 are disposed on opposite sides of the substrate 121.

It should be noted that the number and the kind of the electronic components 122 are not limited as long as the functions required by the circuit board 12 can be realized. For example, the electronic component 122 may include a resistor, a capacitor, a diode, a transistor, or the like, without limitation.

In the electrical box device 1 of the embodiment of the application, in the normal use process, the waterproof top wall 111 faces upward, that is, the top of the electrical box device 1 faces upward, and the bottom faces downward, that is, the circuit board 12 is inversely installed, so that the substrate 111 is installed near the waterproof top wall 111, and under the condition that the appearance size (including the size in the height direction, the size in the length direction and the size in the width direction) of the electrical box 11 is not additionally increased, the substrate 111 has a larger ground clearance, and the waterproof performance of the circuit board 12 is better.

The above-mentioned ground clearance refers to a distance between the substrate 121 and a reference plane, which is a reference mounting surface on which the electrical box 11 is mounted on another structure.

For example, referring to fig. 3, a distance h2 between the substrate 121 and the bottom edge of the waterproof sidewall 112 is greater than a distance h1 between the substrate 121 and the waterproof top wall 111. It should be noted that, in the case of facilitating assembly, the base plate 121 is disposed as close to the waterproof ceiling wall 111 as possible, so that the base plate 121 has as large a height from the ground as possible.

Illustratively, the distance h2 between the base plate 121 and the bottom edge of the watertight side wall 112 is 3 times or more than 3 times the distance h1 between the base plate 121 and the watertight top wall 111, that is, h2 ≧ 3 × h1, e.g., 3 times, 3.5 times, 4 times, 4.6 times, 5 times, 6 times, 7 times, etc.

In some embodiments, any electronic component 122 does not extend beyond the bottom end surface of the waterproof sidewall 112 along the top-bottom direction of the electrical box device 1. That is, all the electronic components 122 are completely accommodated in the waterproof mounting cavity 11 a.

For example, referring to fig. 1, fig. 2 and fig. 3, the waterproof sidewall 112 is provided with a wire through hole 112 a. A wire harness electrically connected to the circuit board 12 is inserted through the wire passing hole 112 a.

In some embodiments, the wire passing hole 112a penetrates through the bottom edge of the waterproof sidewall 112, that is, the wire passing hole 112a is an open notch, and the wiring harness can be disposed into the wire passing hole 112a from the opening of the wire passing hole 112a, so as to facilitate assembly.

In some embodiments, the watertight side walls 112 and the watertight top wall 111 are a one-piece, flame-retardant injection molded part. That is, the electrical box 11 is made of flame retardant plastic material. The flame retardant plastic refers to a plastic material modified, for example, one or a combination of any of flame retardant ABS (Acrylonitrile Butadiene Styrene), flame retardant HIPS (High impact polystyrene), flame retardant PP (Polypropylene), flame retardant PE (Polyethylene), flame retardant PET (Polyethylene terephthalate), flame retardant PBT (Polybutylene terephthalate), and flame retardant PC (Polycarbonate).

On the one hand, the fire-retardant plastics material is convenient for mould plastics out the structure that is used for fixed connection base plate 121 at the in-process an organic whole of moulding plastics, and on the other hand, fire-retardant plastics have fire-retardant characteristic, even circuit board 12 takes place accidents such as being on fire, still can make the burning only take place in waterproof installation cavity 11a, and can not stretch to the electrical apparatus box 11 outside.

For example, in some embodiments, referring to fig. 3, the electrical box 11 is provided with at least one elastic hook 113 extending into the waterproof mounting cavity 11a, and the elastic hook 113 abuts against the bottom edge of the substrate 121 along the top-bottom direction of the electrical box device. In the assembling process, the electrical box 11 can be inverted, the circuit board 12 is placed in the waterproof mounting cavity 11a, the substrate 121 forces each elastic hook 113 to elastically deform, and after the substrate 121 passes over the elastic hooks 113, the elastic hooks 113 recover to deform under the action of self elasticity and abut against the bottom side edge of the substrate 121. In this embodiment, the substrate 121 can be quickly positioned by the elastic hooks 113.

It should be noted that, in the embodiment of the flame-retardant injection-molded part with the waterproof side wall 112 and the waterproof top wall 111 being integrated, each elastic hook 113 is integrally molded with the waterproof side wall 112 and the waterproof top wall 111.

Illustratively, in some embodiments, referring to fig. 3, the electrical box 11 has at least one protrusion 115 protruding from the bottom surface 111a of the waterproof top wall 111, and the screw 13 is inserted through the substrate 121 and screwed into the protrusion 115 to fix the substrate 121 to the protrusion 115. The protrusion 115 can facilitate the assembly of the screw 13, increase the contact area with the screw 1, improve the connection reliability, and prevent the screw 1 from penetrating to the top surface of the waterproof top wall 111.

In some embodiments, the protrusion 115 is pre-provided with a blind threaded hole, and the screw 13 is screwed into the blind threaded hole. In other embodiments, the screws 13 are self-tapping screws that are used to tap the threads in the bosses 115 at the assembly site.

It should be noted that, in some embodiments, the electrical box device 1 is configured with only the elastic hooks 113, and is not configured with the screws, i.e., the circuit board 12 is connected to the electrical box 11 only through the elastic hooks 113. In other embodiments, the electrical box device 1 is configured with only the screw 13 and not with the elastic hook 113, i.e. the circuit board 12 is connected to the electrical box 11 only through the screw 13. In still other embodiments, the electrical box device 1 is configured with the screw 13 and the elastic hook 113, in this embodiment, in the assembling process, the substrate 121 may be initially positioned by the elastic hook 113, and in the process of screwing the screw 13, an operator is not required to manually position the substrate 121, which simplifies the assembling process and saves the assembling time; it should be noted that, in this embodiment, after the screw 13 is tightened, a certain gap may exist between the substrate 121 and the elastic hook 113 along the top-bottom direction of the electrical box device, that is, the substrate 121 and the elastic hook 113 may not be in contact.

The specific shape of the electrical box 11 is not limited, and the structure of the electrical box 11 of the first embodiment and the electrical box 11 of the second embodiment of the present application will be described below with reference to the drawings.

First embodiment

Referring to fig. 1 to 3, in the embodiment, an opening 11b communicating with the waterproof mounting cavity 11a is formed at a bottom side of the electrical box 11. For example, during assembly, the circuit board 12 is placed into the waterproof mounting cavity 11a from the opening 11 b; during maintenance, the circuit board 12 can be taken out of the opening 11 b.

The electronic component 122 is exposed to the bottom side of the electrical box 11. That is, the bottom side of the electric box 11 is open, and the bottom of the electric box 11 is not provided with a structure covering the opening 11 b. In this embodiment, the bottom end surface of the waterproof side wall 112 can be directly abutted to the mounting structure of the electrical equipment, that is, the base in the related art is eliminated, so that the height dimension of the base in the prior art can be omitted, and the electrical box 11 in the embodiment of the present application can enable the substrate 121 to have a larger height above the ground under the condition that the electrical box 11 has the same height dimension.

The waterproof installation cavity 11a communicates with the outside only through the opening 11 b. That is, there are no holes at any position of the watertight side walls 112 and the watertight top wall 111. The electrical box 11 in this embodiment is suitable for the situation where the power of the electronic component 122 is not large and the requirement of the circuit board 12 for heat dissipation is not high, for example, the electrical box 11 of a clothes processing device.

The electrical box 11 is a flame-retardant injection-molded part integrally formed in one piece, that is, the electrical box 11 can be formed into one part by injection molding. So can reduce 11 part numbers of electrical apparatus box, reduce assembly process and step, reduce mould quantity, reduction in production cost.

Second embodiment

In this embodiment, the electrical box 11 includes a bottom plate and a box cover connected to each other, the waterproof side wall 112 and the waterproof top wall 111 are components of the box cover, and the space inside the box cover is the waterproof mounting cavity 11 a. The bottom side of the box cover is open, and the bottom plate is arranged at the bottom side of the box cover and covers the open position of the box cover. In this embodiment, the waterproof mounting cavity 11a is a relatively closed space, and the electronic component 122 is not exposed to the outside of the electrical box 11, that is, the user does not view the electronic component 122 from the outside of the electrical box 11.

The electrical box 11 may be mounted to other structures of the electrical appliance through the base plate.

The box cover in the embodiment can be an integrated sheet metal part or an integrated flame-retardant injection molding part. The bottom plate can be an integrated sheet metal part and also can be an integrated flame-retardant injection molding part.

Referring to fig. 4 to 8, an electrical apparatus provided in the present embodiment includes a body 2, a control panel 3, and an electrical box device 1 according to any of the embodiments.

The control panel 3 is disposed on the body 2, and the control panel 3 is electrically connected to the circuit board 12. The control panel 3 is configured with operation keys, which may be physical keys, knobs, touch keys on a touch screen, and the like, and are not limited herein.

The user operates the control panel 3, the control panel 3 triggers to generate a corresponding electrical signal, the electronic component 122 on the substrate 121 generates a corresponding control signal according to the electrical signal, and controls the working components of the machine body 2 to work according to the control signal.

The specific type of the electrical equipment is not limited, and the electrical box device 1 of the embodiment of the present application can be adopted as long as the electrical box 11 needs to be configured and the electrical equipment with waterproof requirement is available.

Exemplarily, in some embodiments, the electric appliance is a laundry treating apparatus.

The type of the laundry treating apparatus may be a washing machine, a dryer, a washer-dryer, etc.

The structure of the laundry treating apparatus may be a drum type, a pulsator type, or other structures, which is not limited herein.

When the user uses the laundry treating apparatus, the laundry tub and the like carried by the user may have residual water, which may be sprinkled on the top of the laundry treating apparatus, thereby risking entering the inside of the electrical box 11. In addition, the laundry treating apparatus is compact in structure and has a narrow inner space. Therefore, the electrical box device 1 of the embodiment of the present application is suitable for being installed in a narrow space of a clothes treatment apparatus, and can not only improve the waterproof performance of the clothes treatment apparatus, but also give consideration to the compact structure of the clothes treatment apparatus.

In some embodiments, referring to fig. 4 to 8, the machine body 2 includes a box 21, a cylinder, a door 23, and a top cover 22 disposed on the top of the box 21, specifically, the top of the box 21 is open, and the top cover 22 closes the top of the box 21. A laundry loading/unloading opening is formed at the front side of the cabinet 21, and a door 23 is rotatably provided at the front side of the cabinet 21 to close or open the laundry loading/unloading opening.

In this embodiment, the cabinet 21, the door 23, and the top cover 22 constitute an external appearance surface of the laundry treating apparatus.

For example, referring to fig. 9, the control panel 3 has an accommodating space 3a for accommodating the electrical box device 1, a bottom side of the accommodating space 3a is opened to form an opening, the control panel 3 is disposed above the top cover 22, and a portion around the opening of the control panel 3 abuts against a top surface of the top cover 22. That is, the opening of the control panel 3 is closed by the top cover 22 to restrict the electric box device 1 within the accommodation space 3a of the control panel 3.

In some embodiments, the electrical enclosure 11 may be fixedly attached to the control panel 3, i.e., the electrical enclosure 11 is not directly attached to the top cover 22.

In other embodiments, and with continued reference to fig. 9, the electronics housing 11 is supported and attached to the top side of the top cover 22. During assembly, the electrical box device 1 is mounted on the top cover 22 as a pre-assembled unit, for example, by screws or the like, the control panel 3 is covered around the electrical box device 1, and the control panel 3 is connected to the top cover 22.

In some embodiments, the control panel 3 and the substrate 121 both extend along the left and right direction of the top cover 22, referring to fig. 1 and 2, two opposite ends of the electrical box 11 along the left and right direction of the top cover 22 are provided with lugs 114, and the electrical box 11 is connected to the top cover 22 through the lugs 114. In this embodiment, the control panel 3 has a large size in the longitudinal direction, and the accommodation spaces 3a on the left and right sides of the electric box 11 can be fully utilized by disposing the lugs 114 at the opposite ends of the electric box 11 in the left and right directions.

It should be noted that the clothes treating apparatus does not operate uninterruptedly for a long time, and the electronic components 122 on the circuit board 12 do not generate heat continuously, so that even if the electrical box 11 is not provided with a heat dissipation hole, the heat dissipation requirement of the circuit board 12 can be ensured.

In the description of the present application, reference to the description of the terms "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the embodiments of the present application. In this application, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Moreover, various embodiments or examples and features of different embodiments or examples described herein may be combined by one skilled in the art without contradiction.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An electrical box apparatus, comprising:

the electric appliance box (11) comprises a waterproof side wall (112) and a waterproof top wall (111) arranged at the top of the waterproof side wall (112), and the waterproof side wall (112) and the waterproof top wall (111) jointly define a waterproof mounting cavity (11 a);

the circuit board (12) is arranged in the waterproof mounting cavity (11a), the circuit board (12) comprises a substrate (121) and an electronic element (122) arranged on the substrate (121), the substrate (121) is connected with the electric appliance box (11), and the electronic element (122) is arranged on the bottom side of the substrate (121) deviating from the waterproof top wall (111).

2. An electric box arrangement according to claim 1, characterized in that in the top-bottom direction of the electric box arrangement, any of the electronic components (122) does not extend beyond the bottom end face of the waterproof side wall (112).

3. An electrical box arrangement according to claim 1, characterised in that the electrical box (11) is a one-piece, flame-retardant injection moulded part.

4. Electrical box arrangement according to claim 1, characterised in that the distance of the base plate (121) from the bottom edge of the watertight side walls (112) is greater than the distance between the base plate (121) and the watertight top wall (111).

5. An electrical box arrangement according to claim 1, characterized in that the bottom side of the electrical box (11) is provided with an opening (11b) for accessing the circuit board (12), the opening (11b) communicating with the watertight mounting cavity (11a), the electronic component (122) being exposed at the bottom side of the electrical box (11).

6. An electrical box arrangement according to claim 5, characterised in that the watertight mounting chamber (11a) communicates with the outside only through the opening (11 b).

7. An electrical box arrangement according to claim 5, characterised in that the electrical box (11) is provided with at least one resilient catch (113) extending into the waterproof mounting cavity (11a), the resilient catch (113) abutting against the bottom side edge of the base plate (121) in the top-bottom direction of the electrical box arrangement.

8. An electrical box arrangement according to claim 5, characterised in that the electrical box (11) has at least one protrusion (115) protruding from the bottom surface (111a) of the watertight top wall (111), a screw (13) passing through the base plate (121) and screwing into the protrusion (115) to fix the base plate (121) on the protrusion (115).

9. An electrical box arrangement according to claim 1, characterised in that the electrical box (11) comprises a bottom plate and a box cover connected to each other, the watertight side walls (112) and the watertight top wall (111) being part of the box cover, the box cover being open at its bottom side, the bottom plate being arranged at the bottom side of the box cover and covering the open place of the box cover.

10. An electrical apparatus, characterized in that, includes a machine body (2), a control panel (3) and the electrical box device of any claim 1-9, the control panel (3) is arranged on the machine body (2), the control panel (3) is electrically connected with the circuit board (12).

11. The electric appliance according to claim 10, characterized in that it is a laundry treatment apparatus.

12. The electrical apparatus according to claim 11, wherein the machine body (2) comprises a box body (21) and a top cover (22) disposed on top of the box body (21), the control panel (3) has a receiving space (3a) for receiving the electrical box device, a bottom side of the receiving space (3a) is opened to form an opening, and a portion around the opening of the control panel (3) abuts against a top surface of the top cover (22).

13. The electrical apparatus according to claim 12, characterized in that the electrical box (11) is supported and connected to the top side of the top cover (22).

14. The electrical equipment according to claim 12, characterized in that the rear part of the top cover (22) is provided with a sunken platform (221), the sunken platform (221) and the control panel (3) both extend along the left-right direction of the top cover (22), the bottom end of the control panel (3) abuts against the sunken platform (221), and the control panel (3) protrudes from the top surface of the top cover (22).