Navigator for spraying robot
By designing a cooling fan, sliding shield and cleaning unit in the navigator of the spray robot, the problem of air coating adhering to the lidar window reduces positioning accuracy, achieving higher navigation accuracy and longer service life.
Patent Information
- Application Number
- CN202411868974.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-18
- Publication Date
- 2025-03-07
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
When the spraying robot uses lidar to navigate, the air paint is attached to the lidar's window mask, reducing the positioning accuracy of the navigation device, resulting in a decrease in the accuracy of the measurement data, prone to miscalculation, and over time, the accumulation of paint will cause the navigation device to fail positioning.
A navigation device for spraying robots is designed, including a cooling fan, electric push rod, sliding shield, heat sink, filter, and cleaning unit. The cooling fan drives the gas out to form a wind curtain to clean the surface of the sliding shield; the sliding shield prevents the paint from entering to ensure the cleaning of the lidar; the cleaning unit includes a liquid storage tank, an infusion tube, an L-shaped plate, a mounting rod and a wiping sponge to clean the surface of the optical lens.
Effectively prevent paint and dust from adhering to the lidar's windows and optical lenses, improve the positioning accuracy of the navigation device, reduce miscalculation, extend the service life of the navigation device, and ensure the normal operation of the lidar in the outdoor sunny environment.
Smart Images
Figure CN119575350A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of radar navigation, and in particular to a navigator for a spraying robot. Background Art
[0002] Laser radar is a measuring device that emits pulsed lasers. After the laser hits the surface of an object, it is reflected back and received by a receiver. The system then measures and analyzes the laser reflection time to confirm the distance of the object. Therefore, radar lasers are widely used on automatic robots to achieve navigation and obstacle avoidance functions. With the widespread use of automatic spraying robots, spraying robots can achieve intelligent movement to spray building walls through the navigation and obstacle avoidance of laser radar. However, during the spraying operation, the sprayed paint will fill the surrounding environment, and the paint in the air will adhere to the window mask of the laser radar, reducing the positioning accuracy of the navigator, making the accuracy of the measurement data less accurate and more prone to mismeasurement. In addition, as the paint attached to the laser radar mask continues to accumulate and block it, the navigator positioning will inevitably fail under long-term spraying operations. Summary of the invention
[0003] In order to overcome the disadvantage that paint filled in the air will adhere to the window mask of the laser radar, reduce the positioning accuracy of the navigator, reduce the accuracy of the measurement data, and make mismeasurement more likely to occur, the present invention provides a navigator for a spraying robot.
[0004] Technical solution: A navigator for a spraying robot, comprising a shell, a laser radar and an optical lens; a laser radar is arranged in the shell; an optical lens is arranged on the front side of the laser radar; a window is opened on the front side of the shell, and the window is flush with the laser radar; it also includes a cooling fan, an electric push rod, a sliding shield, a heat sink, a filter and a cleaning unit; the shell is fixedly connected to the cooling fan, and the cooling fan is located behind the laser radar; a plurality of air inlets are opened on the rear side of the shell; a plurality of electric push rods are fixedly connected to the shell; all the telescopic parts of the electric push rods are fixedly connected to a sliding shield; a plurality of heat sinks are fixedly connected to the surface of the laser radar; a filter is detachably connected to the air inlet; a cleaning unit for cleaning impurities on the surface of the optical lens is connected to the shell.
[0005] To further explain, a plurality of flow channels are opened on the upper side of the window.
[0006] It is further explained that all the heat sinks are fixedly connected to the housing so that air ducts are formed between adjacent heat sinks.
[0007] It is further explained that the heat sink is provided with a guide portion, and the guide portion is close to the window.
[0008] It is further described that the width of the sliding shield is greater than the width of the viewing window.
[0009] To further explain, the lower side of the window is configured as an inclined surface.
[0010] Further description, the cleaning unit includes a liquid storage tank, a shell, an infusion tube, an L-shaped plate, a mounting rod and a wiping sponge; the outer shell is detachably connected to the liquid storage tank; the outer shell is fixedly connected to the shell, and the liquid storage tank is slidably connected in the shell; the shell is fixedly connected to the infusion tube, the infusion tube is connected to the liquid storage tank, and the infusion tube is located above the optical lens; the infusion tube is provided with two pipe openings, and an L-shaped plate is fixedly connected to each pipe opening of the infusion tube; the sliding shield is detachably connected to two mounting rods; a wiping sponge is commonly fixedly connected to the two mounting rods, and the wiping sponge is in contact with the surface of the laser radar.
[0011] Further description, a slot is provided on the upper side of the wiping sponge.
[0012] It is further explained that the cleaning fluid in the fluid storage tank is an alcohol cleaning fluid.
[0013] Further explanation, it also includes air guide plates; a plurality of air guide plates are fixedly connected to the left and right sides of the shell.
[0014] The beneficial effects are: The rotation of the cooling fan drives the gas to be blown downward from the flow channel along the surface of the sliding shield, and forms a wind curtain on the surface of the sliding shield to clean and protect the surface of the sliding shield, preventing paint and dust in the outside air from adhering to and remaining on the surface of the sliding shield, thereby reducing the positioning accuracy of the laser radar. The cooling fan drives the gas to flow through the heat sink, and at the same time can take away the heat absorbed and guided by the heat sink, thereby bringing the heat generated by the laser radar out of the casing and dissipating the heat of the laser radar.
[0015] By sliding the shield to stop covering the window, the gas is blown out from the window at a faster speed, which can prevent paint and dust in the outside air from entering the shell through the window. The blown gas can also disperse the paint and dust in the path of the laser beam, reducing the scattering and blocking of the emitted laser beam by the paint and dust in the air, thereby ensuring the working effect of the laser radar in strong outdoor sunlight environment.
[0016] The cleaning liquid is sprayed onto the surface of the optical lens through the infusion tube, and under the restriction of the L-shaped plate, the sprayed cleaning liquid will not splash everywhere, and the excess cleaning liquid will fall on the wiping sponge. The surface of the optical lens is then wiped and cleaned by moving the wiping sponge up and down to ensure the normal use of the subsequent lidar; and through the guidance of the wind guide plate, part of the gas can blow air to the surface of the optical lens and the wiping sponge, and the cleaning liquid in the liquid storage tank is alcohol cleaning liquid, which can quickly evaporate and dry the alcohol cleaning liquid to ensure that it can be used quickly without waiting during subsequent use. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1It is a schematic diagram of the structure disclosed by the navigator of the present invention for a spraying robot; Figure 2 A cross-sectional view of a housing disclosed for a navigator of a spraying robot according to the present invention; Figure 3 A state diagram of the movement of the electric push rod and the sliding shield disclosed by the navigator for the spraying robot of the present invention; Figure 4 It is a schematic diagram of the combined structure of the electric push rod, the sliding shield, the elastic telescopic rod and the arc-shaped baffle disclosed in the navigator for the spraying robot of the present invention; Figure 5 A state diagram of the sliding shield disclosed in the navigator for the spraying robot of the present invention moving to shield the viewing window and the flow channel; Figure 6 A schematic diagram of the combined structure of a liquid storage tank, a casing, a liquid infusion tube, an L-shaped plate, a mounting rod and a wiping sponge disclosed in the navigator for a spraying robot of the present invention; Figure 7 The present invention is a schematic diagram of the combined structure of a liquid storage tank, a liquid infusion tube, an L-shaped plate, a wiping sponge and an air guide plate disclosed in the navigator for a spraying robot.
[0018] Markings in the accompanying drawings: 1-housing, 2-laser radar, 3-optical lens, 4-cooling fan, 5-electric push rod, 6-sliding shield, 7-heat sink, 8-filter, 201-liquid storage tank, 21-housing, 202-infusion tube, 203-L-shaped plate, 22-mounting rod, 204-wiping sponge, 205-wind guide plate, 01-window, 02-air inlet, 03-flow channel, 701-guide part, 20401-slot. DETAILED DESCRIPTION
[0019] The present invention will be further described below in conjunction with specific embodiments. The illustrative embodiments and descriptions of the present invention are used to explain the present invention but are not intended to limit the present invention.
[0020] Example 1 A navigation device for a spraying robot, such as Figure 1-Figure 5 As shown, it includes a housing 1, a laser radar 2 and an optical lens 3; the laser radar 2 is arranged in the housing 1; the optical lens 3 is arranged on the front side of the laser radar 2; a window 01 is opened on the front side of the housing 1, and the window 01 is flush with the laser radar 2, and the laser radar 2 emits laser light outward from the window 01 through the optical lens 3; It also includes a cooling fan 4, an electric push rod 5, a sliding shield 6, a heat sink 7, a filter 8 and a cleaning unit; the outer shell 1 is fixedly connected to the cooling fan 4, and the cooling fan 4 is located behind the laser radar 2; a number of air inlet holes 02 are opened on the rear side of the outer shell 1; a number of electric push rods 5 are fixedly connected to the outer shell 1; the telescopic parts of all the electric push rods 5 are commonly fixedly connected to a sliding shield 6; a number of heat sinks 7 are fixedly connected to the surface of the laser radar 2, and the heat sink 7 is made of heat-conducting material, which can absorb and guide the heat generated by the laser radar 2; a filter 8 is bolted to the air inlet 02; and the outer shell 1 is connected to a cleaning unit.
[0021] A plurality of flow channels 03 are provided on the upper side of the viewing window 01 , and the gas is blown downward in front of the sliding shield 6 through the flow channels 03 to form a wind curtain, thereby cleaning and protecting the surface of the sliding shield 6 and preventing external dust from adhering to and staying on the surface of the sliding shield 6 .
[0022] All the heat sinks 7 are fixedly connected to the outer shell 1, so that air ducts are formed between adjacent heat sinks 7. When the heat dissipation fan 4 drives the gas to pass through the heat sink 7 for heat dissipation, the high-temperature gas after heat dissipation can flow toward the window 01 along the formed air duct, so that the high-temperature gas after heat dissipation can quickly leave the laser radar 2 and the heat sink 7, thereby preventing the high-temperature gas after heat dissipation from flowing back near the laser radar 2 and reducing the overall heat dissipation efficiency.
[0023] The heat sink 7 is provided with a guide portion 701 , and the guide portion 701 is close to the window 01 , and can guide the heat dissipation gas to flow to the window 01 , so that the heat-dissipated gas can be quickly discharged to the outside.
[0024] The width of the sliding shield 6 is greater than the width of the window 01. When the navigator stops working, the sliding shield 6 is controlled to move to cover the window 01, and the sliding shield 6 continues to be controlled to move, covering the window 01 and the flow channel 03 at the same time, so that when the navigator stops working, external dust cannot enter the housing 1 through the flow channel 03.
[0025] The lower side of the window 01 is set as an inclined surface, so that the gas blown out of the flow channel 03 can be blown downward along the surface of the shell 1 to reduce dust and impurities attached to the window 01.
[0026] The device is installed on the spraying robot. When the spraying robot works normally indoors, the electric push rod 5 is controlled to drive the sliding shield 6 to move, so that the sliding shield 6 moves to the window 01, and the window 01 is blocked by the sliding shield 6, so that the external dust cannot enter the inside of the shell 1, thereby protecting the laser radar 2; when measuring and positioning, the laser radar 2 is controlled to emit a laser beam, the laser beam passes through the optical lens 3, and is emitted outward through the sliding shield 6. When the laser beam encounters an obstacle, it is reflected back and received by the corresponding receiver in the laser radar 2 and systematically analyzed, thereby navigating and avoiding obstacles for the spraying robot. However, there will be more paint and dust diffused in the air environment of the spraying operation, and the diffused paint and dust are easy to attach to The surface of the sliding shield 6 reduces the positioning accuracy of the laser radar 2, and the accuracy of the measurement data is reduced; therefore, when the laser radar 2 is working, the cooling fan 4 is controlled to work at the same time, and the rotation of the cooling fan 4 drives the external gas to pass through the filter 8 and enter the outer shell 1 from the air inlet 02. When the laser beam passes through the optical lens 3 and is emitted outward through the sliding shield 6, the gas entering the outer shell 1 is simultaneously blown downward from the flow channel 03 along the surface of the sliding shield 6, and a wind curtain is formed on the surface of the sliding shield 6 to clean and protect the surface of the sliding shield 6, thereby preventing paint and dust in the external air from adhering to and staying on the surface of the sliding shield 6, reducing the positioning accuracy of the laser radar 2, and ensuring that the navigator can perform measurement and positioning work normally during spraying.
[0027] Moreover, when the laser radar 2 is working, it emits laser light by converting electrical energy into light energy, and heat is generated in the energy conversion process. The laser radar 2 is arranged in a relatively closed shell 1, so as to prevent external coatings from contacting the laser radar 2 and affecting the normal use of the laser radar 2. The heat generated by the operation of the laser radar 2 is accumulated in the shell 1, and the heat is difficult to dissipate, which makes it easy for the laser radar 2 to form a high temperature during operation, accelerate the damage of the internal electrical parts, and reduce the service life of the laser radar 2; therefore, a heat sink 7 is provided between the shell 1 and the laser radar 2. When the cooling fan 4 works to drive the gas flow, the gas first passes through the heat sink 7, takes away the heat absorbed and guided by the heat sink 7, and then blows out from the flow channel 03 at the window 01, thereby bringing the heat generated by the laser radar 2 out of the shell. 1, the laser radar 2 is cooled to prevent the laser radar 2 from overheating, damaging its internal electrical parts and reducing its service life. At the same time, an air duct is formed between adjacent heat sinks 7. When the heat dissipation fan 4 drives the gas to pass through the heat sink 7 for heat dissipation, the high-temperature gas after heat dissipation can flow toward the window 01 along the formed air duct, so that the high-temperature gas after heat dissipation can quickly leave the laser radar 2 and the heat sink 7, and avoid the high-temperature gas after heat dissipation from flowing back near the laser radar 2, thereby reducing the overall heat dissipation efficiency. The heat sink 7 is provided with a guide portion 701, and the guide portion 701 is close to the window 01. The high-temperature gas after heat dissipation can flow to the window 01 under the guidance of the guide portion 701, so that the gas after heat dissipation can be quickly discharged to the outside, and the high-temperature gas after heat dissipation can be prevented from flowing back at a dead corner in the outer shell 1, thereby affecting the heat dissipation effect of the overall navigator.
[0028] At the same time, when the spraying robot works outdoors, due to the outdoor sunlight, the light is stronger, the laser radar 2 needs to emit a stronger laser beam for positioning, and the cooling fan 4 needs to have a higher heat dissipation capacity, and the sliding shield 6 will limit the emission of the laser beam; therefore, when the spraying robot works outdoors during the day, first control the electric push rod 5 to drive the sliding shield 6 to move upward, such as Figure 3As shown, the sliding shield 6 moves to stop blocking the window 01. When working, the laser radar 2 emits a higher power laser beam through the optical lens 3 and directly shoots out from the window 01 to perform measurement and positioning, ensuring that the laser radar 2 can also perform measurement and positioning normally in an outdoor environment with strong sunlight. At this time, since the laser radar 2 works at a higher power, a higher heat dissipation capacity is correspondingly required to ensure the normal operation of the laser radar 2. Therefore, when working outdoors, the cooling fan 4 is controlled to rotate at a higher power to drive more gas flow. At the same time, the sliding shield 6 stops blocking the window 01, and more gas can be directly emitted from the window 01. 1 is blown outward, thereby improving the overall airflow convection effect, and further improving the heat dissipation effect of the laser radar 2, preventing the laser radar 2 from generating a higher temperature when working at high power. Failure to dissipate heat in time may cause damage to the laser radar 2; and, when the sliding shield 6 stops covering the window 01, the gas is blown outward from the window 01 at a faster speed, which can prevent the paint and dust in the outside air from entering the housing 1 through the window 01, and the blown gas can also disperse the paint and dust in the laser beam path, reducing the scattering and blocking of the emitted laser beam by the paint and dust in the air, thereby ensuring the working effect of the laser radar 2 in an outdoor environment with strong sunlight.
[0029] Moreover, after the spraying robot completes the spraying operation, the laser radar 2 is first controlled to stop working, and then the electric push rod 5 is controlled to drive the sliding shield 6 to move down and reset, and the window 01 is blocked again, so that the paint and dust from the outside cannot enter the inside of the shell 1, and the width of the sliding shield 6 is greater than the width of the window 01. When the sliding shield 6 moves to block the window 01, the sliding shield 6 is continued to be controlled to move, and the flow channel 03 is blocked while blocking the window 01. Figure 5 As shown, when the machine stops working, external dust cannot enter the housing 1 through the flow channel 03.
[0030] Example 2 On the basis of Example 1, Figure 6-Figure 7 As shown, the cleaning unit includes a liquid storage tank 201, a casing 21, an infusion tube 202, an L-shaped plate 203, a mounting rod 22 and a wiping sponge 204; the casing 1 is plugged with the liquid storage tank 201; the casing 1 is fixedly connected to the casing 21, and the liquid storage tank 201 is slidably connected in the casing 21; the casing 21 is fixedly connected to the infusion tube 202, the infusion tube 202 is connected to the liquid storage tank 201, and the infusion tube 202 is located above the optical lens 3; the infusion tube 202 is provided with two pipe openings, and an L-shaped plate 203 is fixedly connected to each pipe opening of the infusion tube 202; the sliding shield 6 is bolted to two mounting rods 22; the two mounting rods 22 are commonly fixedly connected to a wiping sponge 204, and the wiping sponge 204 is in contact with the surface of the laser radar 2.
[0031] A slot 20401 is provided on the upper side of the wiping sponge 204 . The L-shaped plate 203 can be inserted into the slot 20401 by moving the wiping sponge 204 upward, and the cleaning liquid remaining on the L-shaped plate 203 and the infusion tube 202 can be wiped and cleaned by the wiping sponge 204 .
[0032] The cleaning liquid in the liquid storage tank 201 is an alcohol cleaning liquid. After cleaning, the alcohol cleaning liquid can quickly dry and evaporate, and the evaporated alcohol can disinfect the area near the window 01.
[0033] It also includes an air guide plate 205; a plurality of air guide plates 205 are fixedly connected to the left and right sides of the housing 1, and the air is guided by the air guide plates 205 so that the air can be blown toward the optical lens 3 and the wiping sponge 204 to dry them.
[0034] When the sliding shield 6 moves to open the window 01, the laser radar 2 emits a laser beam through the optical lens 3 to perform work, and the optical lens 3 is exposed to the outside world at the same time. Compared with manual work, the automatic spraying robot has the advantage of being able to continuously and uninterruptedly spray the surface of the object. The optical lens 3 is exposed to the outside world for a long time. As the equipment is used for a long time, the external paint still adheres to the surface of the optical lens 3. When the equipment is stored, the dust in the outer shell 1 is also easy to adhere to the surface of the optical lens 3, and then block or scatter the laser in subsequent use, resulting in a significant decrease in measurement accuracy. When the equipment is manually maintained and cleaned later, it is difficult for the optical lens 3 located in the outer shell 1 to be cleaned manually. Therefore, before the navigator works, Figure 6 and Figure 7As shown, the electric push rod 5 is first controlled to drive the sliding shield 6 to move, and the sliding shield 6 drives the wiping sponge 204 to move below the optical lens 3, and then the liquid storage tank 201 is manually pressed down, so that the liquid storage tank 201 moves down in the casing 21, and the infusion tube 202 is inserted into the liquid storage tank 201 and communicated with the liquid storage tank 201, and then the cleaning liquid is sprayed onto the surface of the optical lens 3 through the infusion tube 202, and under the restriction of the L-shaped plate 203, the sprayed cleaning liquid will not splash everywhere, and the excess cleaning liquid will fall on the wiping sponge 204, and then the electric push rod 5 is controlled to drive the sliding shield 6 and the wiping sponge 204 to move up and down on the surface of the optical lens 3, and the surface of the optical lens 3 is wiped and cleaned by the up and down movement of the wiping sponge 204 to ensure the normal use of the subsequent laser radar 2; and after spraying the cleaning liquid, the tube mouth of the infusion tube 202 and the surface of the L-shaped plate 203 There is residual cleaning liquid on the surface, and then the electric push rod 5 is controlled to drive the wiping sponge 204 to move upward, so that the wiping sponge 204 contacts the L-shaped plate 203, and the L-shaped plate 203 is stuck in the slot 20401 of the wiping sponge 204, and the cleaning liquid remaining on the tube mouth of the infusion tube 202 and the surface of the L-shaped plate 203 can be absorbed by the wiping sponge 204; at the same time, when the wiping sponge 204 completes wiping and cleaning, the cooling fan 4 is controlled to rotate and blow gas again, and part of the gas can be blown to the surface of the optical lens 3 and the wiping sponge 204 through the guidance of the wind guide plate 205, and the cleaning liquid in the liquid storage tank 201 is alcohol cleaning liquid, which can quickly evaporate and dry the alcohol cleaning liquid to ensure that it can be used quickly without waiting during subsequent use, and the volatilized alcohol is blown out from the window 01 and the flow channel 03 driven by the gas to disinfect the surrounding area.
[0035] During the use of the navigator, the liquid storage tank 201 can be quickly plugged in and out for replacement. When the wiping sponge 204 is continuously used and has many stains on the surface, the mounting rod 22 and the wiping sponge 204 can be manually disassembled and replaced.
[0036] Although the present disclosure has been described with respect to only a limited number of embodiments, those skilled in the art having benefit of this disclosure will appreciate that various other embodiments can be devised without departing from the scope of the present invention. Accordingly, the scope of the present invention should be limited only by the appended claims.
Claims
1. A navigator for a spraying robot, comprising a housing (1), a laser radar (2) and an optical lens (3); the laser radar (2) is arranged in the housing (1); the optical lens (3) is arranged on the front side of the laser radar (2); a window (01) is opened on the front side of the housing (1), and the window (01) is flush with the laser radar (2); the characteristics are: The invention also comprises a cooling fan (4), an electric push rod (5), a sliding shield (6), a heat sink (7), a filter (8) and a cleaning unit; the outer shell (1) is fixedly connected to the cooling fan (4), and the cooling fan (4) is located behind the laser radar (2); a plurality of air inlet holes (02) are opened on the rear side of the outer shell (1); a plurality of electric push rods (5) are fixedly connected to the outer shell (1); the telescopic parts of all the electric push rods (5) are fixedly connected to a sliding shield (6); a plurality of heat sinks (7) are fixedly connected to the surface of the laser radar (2); a filter (8) is detachably connected to the air inlet hole (02); and a cleaning unit for cleaning impurities on the surface of the optical lens (3) is connected to the outer shell (1).
2. A navigator for a spraying robot according to claim 1, characterized in that: A plurality of flow channels (03) are opened on the upper side of the viewing window (01).
3. A navigator for a spraying robot according to claim 1, characterized in that: All the heat sinks (7) are fixedly connected to the outer shell (1), so that air ducts are formed between adjacent heat sinks (7).
4. The navigator for a spraying robot according to claim 1, characterized in that: The heat sink (7) is provided with a flow guide portion (701), and the flow guide portion (701) is close to the viewing window (01).
5. The navigator for a spraying robot according to claim 1, characterized in that: The width of the sliding shield (6) is greater than the width of the viewing window (01).
6. The navigator for a spraying robot according to claim 1, characterized in that: The lower side of the window (01) is set to be beveled.
7. The navigator for a spraying robot according to claim 1, characterized in that: The cleaning unit comprises a liquid storage tank (201), a casing (21), an infusion tube (202), an L-shaped plate (203), a mounting rod (22) and a wiping sponge (204); the casing (1) is detachably connected to the liquid storage tank (201); the casing (1) is fixedly connected to the casing (21), and the liquid storage tank (201) is slidably connected in the casing (21); the casing (21) is fixedly connected to the infusion tube (202), the infusion tube (202) is in communication with the liquid storage tank (201), and the infusion tube (202) is located above the optical lens (3); the infusion tube (202) is provided with two tube openings, and each tube opening of the infusion tube (202) is fixedly connected to an L-shaped plate (203); the sliding shield (6) is detachably connected to two mounting rods (22); the two mounting rods (22) are commonly fixedly connected to a wiping sponge (204), and the wiping sponge (204) is in contact with the surface of the laser radar (2).
8. A navigator for a spraying robot according to claim 7, characterized in that: A slot (20401) is formed on the upper side of the wiping sponge (204).
9. A navigator for a spraying robot according to any one of claims 7-8, characterized in that: The cleaning liquid in the liquid storage tank (201) is an alcohol cleaning liquid.
10. A navigator for a spraying robot according to claim 9, characterized in that: It also includes an air guide plate (205); a plurality of air guide plates (205) are fixedly connected to the left side and the right side of the housing (1).