CN114407791A

CN114407791A - Automobile and environment sensing device thereof

Info

Publication number: CN114407791A
Application number: CN202210090087.0A
Authority: CN
Inventors: 陶旬; 张军; 李宏禹; 陈基华; 艾传智
Original assignee: Zhejiang Geely Holding Group Co Ltd; Geely Automobile Research Institute Ningbo Co Ltd
Current assignee: Zhejiang Geely Holding Group Co Ltd; Geely Automobile Research Institute Ningbo Co Ltd
Priority date: 2022-01-25
Filing date: 2022-01-25
Publication date: 2022-04-29

Abstract

An automobile and a environment sensing device thereof, the environment sensing device comprises: a host, comprising: the shell comprises a base and a shell body, wherein the base is used for being rotationally connected with a vehicle body; the sensor assembly is arranged on one side of the base and used for acquiring environmental information; the driving mechanism is used for driving the base to rotate; wherein the base is rotatable to a position that places the sensor assembly outside the vehicle body and also rotatable to a position that places the sensor assembly inside the vehicle body. When the sensor assembly is needed, the main machine is driven to rotate only through the driving mechanism, so that the sensor assembly is overturned out of the vehicle body, and the detection range of the sensor assembly is large. When the sensor assembly is not needed to be used, the driving host machine is only needed to be driven to rotate through the driving mechanism, so that the sensor assembly is turned over into the automobile body, the sensor assembly cannot protrude out of the automobile body, wind resistance and wind noise can be reduced at the moment, and the sensor assembly is not easy to damage.

Description

Automobile and environment sensing device thereof

Technical Field

The present disclosure relates to an intelligent driving assistance technology for a vehicle, and more particularly, to a vehicle and an environment sensing device thereof.

Background

With the rapid development of the scientific and technological era, the intelligent driving auxiliary system of the automobile is widely applied. The intelligent driving auxiliary system of the automobile has great potential in the aspects of improving road safety and traffic efficiency, and the accurate perception of the traffic environment is the basis for planning, deciding and controlling the intelligent driving auxiliary system.

The vision sensor, which is the most commonly used sensor for intelligent driving assistance systems, is capable of acquiring detailed shape and texture information of the surrounding environment. However, vision sensors are susceptible to light and weather conditions, which can lead to reduced sensor performance and susceptibility to miscalculation and even failure. The solid laser radar is used as the most common sensor of the intelligent driving assistance system, has wide detection range, high resolution, rich information content, low cost and great advantage, can work all weather, and is suitable for the specification standard of automobile electronic components.

The sensors are arranged outside the automobile and protrude out of the outer surface of the automobile, so that the detection range of the sensors can be enlarged, but the sensors do not need to work all the time, for example, when the intelligent driving auxiliary system is closed, the sensors stop working, and the sensors protrude out of the outer surface of the automobile, so that the wind resistance is increased, and the oil consumption and the wind noise are increased. Especially, in a parking state, a sensor protruding from the outer surface of the automobile is easily damaged.

Disclosure of Invention

In order to solve the above technical problem, the present application provides an environment sensing apparatus, which includes:

a host, comprising:

the shell comprises a base and a shell body, wherein the base is used for being rotationally connected with a vehicle body;

the sensor assembly is arranged on one side of the base and used for acquiring environmental information; and

the driving mechanism is used for driving the base to rotate;

wherein the base is rotatable to a position that places the sensor assembly outside the vehicle body and also rotatable to a position that places the sensor assembly inside the vehicle body.

In an exemplary embodiment, the housing further includes a shaft extending from one side of the base;

the driving mechanism comprises a motor and a transmission mechanism;

the transmission mechanism is in transmission connection with a main shaft of the motor and the rotating shaft, and is used for transmitting the torque output by the motor to the rotating shaft so as to enable the main machine to rotate.

In an exemplary embodiment, the transmission is a gear transmission, a belt transmission, or a chain transmission.

In an exemplary embodiment, the spindle is parallel to the axis of rotation;

the transmission mechanism comprises a driving wheel sleeved on the main shaft, a driven wheel sleeved on the rotating shaft and a transmission belt hooped on the driving wheel and the driven wheel.

In an exemplary embodiment, the spindles extend from opposite sides of the base;

the motor also comprises a machine body which can be relatively fixed with the vehicle body, and the main shaft penetrates through the machine body;

the two driving wheels are respectively sleeved at two opposite ends of the main shaft;

the two driven wheels are respectively sleeved at two opposite ends of the rotating shaft and are respectively aligned with the two driving wheels;

the transmission belt is provided with two belts, one belt is hooped on one group of driven wheels and driving wheels which are aligned with each other, and the other belt is hooped on the other group of driven wheels and driving wheels which are aligned with each other.

In an exemplary embodiment, the environment sensing device further includes a first support for connecting the vehicle body, and the first support is provided with a first shaft hole in clearance fit with the rotating shaft.

the first support is provided with two, and the first shaft hole of two first supports is in the suit respectively in the relative both ends of pivot.

In an exemplary embodiment, the base is configured as a plate-like structure.

In an exemplary embodiment, the housing includes a protective shell disposed on a panel of the base, and the housing and the protective shell enclose a cavity for receiving the sensor assembly.

In an exemplary embodiment, the protective shell is removably coupled to the base.

In an exemplary embodiment, a light-transmissive window is disposed on the protective shell.

In an exemplary embodiment, the sensor assembly includes a vision sensor, a lidar, a millimeter wave radar, and/or an ultrasonic radar.

In an exemplary embodiment, the lidar is a solid-state lidar.

The application also provides an automobile, which comprises the environment sensing device and an automobile body;

the base is rotatably connected to the vehicle body.

In one illustrative embodiment, the vehicle body includes a roof provided with a mounting opening;

the base is disposed in the mounting opening.

In an exemplary embodiment, the mounting opening is provided at a front end of the ceiling.

In an exemplary embodiment, the environmental sensing apparatus further includes a sealing member disposed between an inner wall of the mounting opening and a side surface of the base for closing a gap between the base and the inner wall of the mounting opening.

When the sensor assembly is needed to be used, the main machine is driven to rotate only through the driving mechanism, so that the sensor assembly rotates to the outer side of the base, the sensor assembly overturns to the outside of the vehicle body, the sensor assembly protrudes out of the vehicle body, and the detection range of the sensor assembly is large. When the sensor assembly is not needed to be used, the driving host machine is only needed to be driven to rotate through the driving mechanism, so that the sensor assembly rotates to the inner side of the base, the sensor assembly overturns into the automobile body at the moment, the sensor assembly cannot protrude out of the automobile body, wind resistance and wind noise can be reduced at the moment, and the sensor assembly is not easy to damage.

Additional features and advantages of the application will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the application. Other advantages of the present application may be realized and attained by the instrumentalities and combinations particularly pointed out in the specification and the drawings.

Drawings

The accompanying drawings are included to provide an understanding of the present disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the examples serve to explain the principles of the disclosure and not to limit the disclosure.

FIG. 1 is a schematic view of a portion of a vehicle roof in an embodiment of the present application;

FIG. 2 is a disassembled schematic view of an environment sensing device according to an embodiment of the present disclosure;

FIG. 3 is a partial schematic view of an environment sensing apparatus according to an embodiment of the present application;

FIG. 4 is a partial schematic view of an environment sensing apparatus according to an embodiment of the present application;

FIG. 5 is a schematic view of an environment sensing apparatus in an operating state according to an embodiment of the present disclosure;

FIG. 6 is a schematic view of an environment sensing apparatus in an unused state according to an embodiment of the present disclosure;

FIG. 7 is a schematic top view of an environment sensing device according to an embodiment of the present application;

FIG. 8 is a schematic cross-sectional view of a seal in an embodiment of the present application;

FIG. 9 is a schematic perspective view of an environment sensing device according to an embodiment of the present application;

FIG. 10 is a schematic cross-sectional view of a light-transmitting plate in an embodiment of the present application;

FIG. 11 is a partial schematic view of the light-transmitting plate of FIG. 10.

Detailed Description

As shown in fig. 1, fig. 1 shows a partial schematic view of a motor vehicle. The automobile comprises a body 2 and an environment sensing device 1. The environment sensing device 1 is mounted on the vehicle body 2 and is rotatably connected with the vehicle body 2.

As shown in fig. 2, the vehicle body 2 includes a roof 21. The ceiling 21 has a substantially plate-like structure. The ceiling 21 is preferably of sheet metal construction. The roof 21 is located on the top of the vehicle body 2. The ceiling 21 is provided with a mounting opening 211. The mounting opening 211 penetrates the ceiling 21. The mounting opening 211 may be a substantially rectangular hole.

As shown in fig. 3 and 4, the environmental sensor 1 may be mounted on a ceiling 21 of the vehicle body 2. The environment sensing apparatus 1 includes a main body 11, a driving mechanism 12, a first support 14, and a second support 15. The first pedestal 14 and the second pedestal 15 are provided on the ceiling 21. The first pedestal 14 and the second pedestal 15 may be both provided on the side facing downward from the ceiling 21. The first holders 14 may be provided in two, and the two first holders 14 are respectively provided at opposite sides of the mounting opening 211. The first support 14 is provided with a first shaft hole. The first axial holes of the two first supports 14 are aligned with each other. The second holder 15 is disposed on the rear side of the mounting opening 211.

The main body 11 includes a housing 110, a sensor assembly 113, and a rotation shaft 114. The housing 110 includes a base 111 and a protective case 112. The base 111 may be configured in a plate-like structure, for example, a substantially rectangular plate-like structure. The protective shell 112 is disposed on one surface of the base 111, and the protective shell 112 protrudes from the base 111. The protective shell 112 and the base 111 enclose a cavity. The rotation shafts 114 extend from opposite sides of the base 111. The rotating shaft 114 is fixedly connected with the base 111. The base 111 of the housing 110 is disposed on the mounting opening 211. Two ends of the rotating shaft 114 are respectively inserted into the first shaft holes of the two first supports 14. The rotating shaft 114 is in clearance fit with the first shaft hole. The base 111 of the housing 110 is rotatably connected to the ceiling 21 of the vehicle body 2.

The sensor assembly 113 is disposed at one side of the base 111 and located in a cavity enclosed by the protective shell 112 and the base 111. The sensor assembly 113 is used to collect environmental information about the environment in which the vehicle is located. The sensor assembly 113 may be a vision sensor, a lidar, a millimeter wave radar, and/or an ultrasonic radar. In this embodiment, the sensor assembly 113 includes a lidar that is a solid lidar that may be a solid lidar employing a rotating polygonal mirror scheme or a double wedge prism scheme.

The drive mechanism 12 includes a motor 121 and a transmission mechanism 122. The transmission 122 may be a gear transmission, a belt transmission, or a chain transmission. The motor 121 is used for driving the housing 110 to rotate. The transmission mechanism 122 is drivingly connected to the main shaft 1212 of the motor 121 and the rotating shaft 114 of the housing 110, and the transmission mechanism 122 is used for transmitting the torque output by the motor 121 to the rotating shaft 114 of the housing 110 to rotate the housing 110.

The motor 121 includes a body 1211 and a spindle 1212. The body 1211 of the motor 121 is fixed to the second mount 15. The second mount 15 may be constructed in an arch-shaped bar structure, and the second mount 15 hoops the body 1211 of the motor 121 on the inner surface of the ceiling 21. The body 1211 of the motor 121 and the second support 15 may be clamped, snapped, screwed or welded. A main shaft 1212 of the motor 121 protrudes from the body 1211. The main shaft 1212 of the motor 121 and the rotation shaft 114 of the housing 110 are parallel to each other.

The transmission mechanism 122 is a belt transmission mechanism 122. The transmission mechanism 122 includes a driving pulley 1221, a driven pulley 1222, and a transmission belt 1223. The driving wheel 1221 is fitted around the main shaft 1212 of the motor 121. The driving wheel 1221 and the main shaft 1212 of the motor 121 may be in a key connection, such as a spline connection or a flat key connection, and the driving wheel 1221 and the main shaft 1212 of the motor 121 may also be in an interference fit. The driven wheel 1222 is sleeved on the rotating shaft 114 of the main machine 11, and the driven wheel 1222 is flush with the driving wheel 1221. The driven wheel 1222 and the rotating shaft 114 of the main machine 11 may be in a key connection, such as a spline connection or a flat key connection, or the driven wheel 1222 and the rotating shaft 114 of the main machine 11 may be in an interference fit. The belt 1223 is configured in an endless shape. The belt 1223 has flexibility. The belt 1223 is looped over the driving wheel 1221 and the driven wheel 1222, and the driving wheel 1221 and the driven wheel 1222 tension the belt 1223. The driving pulley 1221 and the driven pulley 1222 may each be configured as a pulley, and the transmission belt 1223 may be configured as a belt. The driving pulley 1221 and the driven pulley 1222 may also be configured as synchronous pulleys, and the transmission belt 1223 may be configured as a synchronous belt.

When the main shaft 1212 of the motor 121 rotates, the driving wheel 1221 is driven to rotate, when the driving wheel 1221 rotates, the driven wheel 1222 is driven to rotate by the driving belt 1223, when the driven wheel 1222 rotates, the rotating shaft 114 is driven to rotate, and when the rotating shaft 114 rotates, the main machine 11 is driven to rotate around the rotating shaft 114.

As shown in fig. 5, when the sensor assembly 113 needs to be used, the main machine 11 only needs to be driven to rotate by the driving mechanism 12, so that the sensor assembly 113 rotates to the outer side of the base 111, at this time, the sensor assembly 113 is turned over to the outside of the vehicle body, the sensor assembly 113 protrudes out of the vehicle body, and the detection range of the sensor assembly 113 is large. As shown in fig. 6, when the sensor assembly 113 is not needed, the main body 11 is driven to rotate only by the driving mechanism 12, so that the sensor assembly 113 rotates to the inner side of the base 111, at this time, the sensor assembly 113 is turned into the vehicle body, the sensor assembly 113 does not protrude out of the vehicle body, at this time, wind resistance and noise are reduced, and the sensor assembly 113 is not easily damaged.

Install environment sensing device 1 on the ceiling 21 of car, environment sensing device 1's position is higher, and sensor assembly 113's detection scope is bigger, and is wider, has effectively reduced the detection blind area, has improved the security of driving a vehicle.

In one exemplary embodiment, the mounting opening 211 is provided at the front end of the ceiling 21. That is, the mounting opening 211 is provided at one end of the ceiling 21 near the front windshield 24. In this way, the environment sensing apparatus 1 is also located at the front end of the ceiling 21, and the environment sensing apparatus 1 can measure a wide area in front of the vehicle.

In an exemplary embodiment, as shown in fig. 7, the main shaft 1212 of the motor 121 extends from opposite ends of the body 1211 of the motor 121. The driven wheels 1222 are provided in two, and the two driven wheels 1222 are respectively provided at opposite ends of the main shaft 1212 of the motor 121. Two driving wheels 1221 are provided, and the two driving wheels 1221 are respectively provided at opposite ends of the rotating shaft 114. Two drive wheels 1221 are aligned with two driven wheels 1222 of the belt, respectively. The belts 1223 are provided in two, one belt 1223 trained about one set of aligned driven wheels 1222 and drive wheels 1221, and the other belt 1223 trained about another set of aligned driven wheels 1222 and drive wheels 1221.

The rotating shaft 114 drives the two driving wheels 1221 to rotate synchronously, the two driving wheels 1221 respectively drive the two driven wheels 1222 to rotate synchronously through the two transmission belts 1223, and the two driven wheels 1222 drive the rotating shaft 114 to rotate synchronously, so that the transmission mechanism 122 can transmit the torque output by the main shaft 1212 to the rotating shaft 114 more stably. In addition, as the transmission belt 1223 is tensioned, the transmission belt 1223 applies mutually close acting force to the driven wheel 1222 and the driving wheel 1221, so that the two driving wheels 1221 respectively apply acting force close to the main machine 11 to the main shaft 1212 from two ends of the main shaft 1212, so that the main shaft 1212 is stressed more balanced; meanwhile, the two driven wheels 1222 apply a force to the rotating shaft 114 from both ends of the rotating shaft 114 to approach the motor 121, so that the force applied to the rotating shaft 114 is more balanced.

In an exemplary embodiment, the protective shell 112 is removably coupled to the base 111. The protective shell 112 and the base 111 may be connected by screws or snaps.

Because the protective housing 112 and the base 111 are detachably connected, when the sensor assembly 113 needs to be maintained, the protective housing 112 and the base 111 can be detached, and the maintenance is more convenient.

In an exemplary embodiment, as shown in fig. 2 and 8, the environmental sensing device 1 further includes a sealing member 3. The sealing member 3 is an elastic member. The seal 3 may be made of rubber or silicone. The seal 3 is of annular design. The seal 3 is fitted over the base 111 when the base 111 is rotated to be flush with the ceiling 21, the seal 3 being located between the side surface of the base 111 and the inner wall of the mounting opening 211. The seal 3 serves to close a gap between the base 111 and the inner wall of the mounting opening 211. The sealing member 3 may be fixed on an inner wall of the mounting opening 211.

The seal 3 prevents fluid from passing from outside the vehicle body through the gap into the vehicle body, for example, prevents air flow and rain water from entering from the gap into the vehicle body.

In an exemplary embodiment, an annular channel 31 is provided in the seal 3, the annular channel 31 extending in the circumferential direction of the seal 3. Thus, the deformation range of the sealing element 3 is larger, a wider gap can be blocked, and the sealing performance of the sealing element 3 is better.

In an exemplary embodiment, as shown in fig. 9-11, a light transmissive window 1121 is further disposed on the protective shell 112. The light transmission window 1121 is disposed at a side of the protective case 112. The light transmission window 1121 transmits light. In a state where the base 111 is turned over to the protective case 112 facing upward, the light transmission window 1121 of the protective case 112 faces forward.

When the sensor assembly 113 comprises a vision sensor, the vision sensor can acquire an image of the surrounding environment of the automobile through the light-transmitting window 1121; when the sensor assembly 113 includes a solid-state lidar, laser energy emitted by the solid-state lidar passes through the light-transmissive window 1121. Since the light transmission window 1121 of the protective case 112 faces forward in a state where the base 111 is turned to the protective case 112 facing upward, the vision sensor and the solid laser radar can detect forward.

In an exemplary embodiment, the light transmissive window 1121 is configured as a bar-shaped window, and opposite ends of the light transmissive window 1121 extend from the front side surface of the protective case 112 to the other two side surfaces adjacent to the front side surface, respectively.

Thus, the light transmission window 1121 has a larger light transmission range, the solid laser radar has a larger scanning range, and the visual sensor can have a larger shooting range.

In an exemplary embodiment, the housing 110 further includes a light transmissive panel 115. The light-transmitting plate 115 can be made of a transparent material or a translucent material. The light-transmitting plate 115 covers the light-transmitting window 1121 and seals the light-transmitting window 1121.

The light-transmitting plate 115 prevents rain water dust from entering the housing 110 through the light-transmitting window 1121 to damage the sensor module 113.

In an exemplary embodiment, as shown in fig. 10 and 11, the light-transmitting plate 115 is further provided with a water chute 1151. Chute 1151 is recessed into protective shell 112. The water chute 1151 is configured as a strip, and the water chute 1151 extends along the edge of the light-transmitting plate 115. The water chute 1151 may be configured in a ring shape to be filled with the edge of the light-transmitting plate 115.

In the rainy day, the water flowing from the protective case 115 to the light-transmitting plate 115 falls into the uppermost water chute 1151 and then flows along the water chute 1151 to the bottom of the light-transmitting plate 115, that is, the water is guided by the water chute 1151 to flow along the edge of the light-transmitting plate 115, so that the water does not affect the detection of the sensor assembly, and meanwhile, the water can be prevented from being accumulated on the light-transmitting plate 115.

In an exemplary embodiment, as shown in fig. 2, the edge of the mounting opening 211 of the ceiling 21 is provided with a stiffener 221. The reinforcing rib 221 may be a flange of the ceiling 21. The reinforcing rib 221 extends from the edge of the mounting opening 211 toward the inside of the ceiling 21. The reinforcing rib plate 221 may reinforce the structural strength of the ceiling 21 in the vicinity of the installation opening 211, so that the environmental sensing device 1 can be more stably supported.

The rib plate 221 is provided with a relief groove 222. The slot 222 is for the shaft 114 to pass through. The receding groove 222 is disposed between the first support 14 and the base 111, and the rotating shaft 114 passes through the receding groove 222 and is rotatably connected to the first support 14.

In another exemplary embodiment, the interior walls of the mounting opening 211 are coated with a water-resistant coating. The waterproof coating abuts against the housing 110, and the waterproof coating can block a gap between the housing 110 and the inner wall of the mounting opening 211.

The waterproof coating can prevent fluid from passing through the gap from outside the vehicle body 2 into the vehicle body 2, for example, prevent rainwater from entering the vehicle body 2 from the gap.

The present application describes embodiments, but the description is illustrative rather than limiting and it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible within the scope of the embodiments described herein. Although many possible combinations of features are shown in the drawings and discussed in the detailed description, many other combinations of the disclosed features are possible. Any feature or element of any embodiment may be used in combination with or instead of any other feature or element in any other embodiment, unless expressly limited otherwise.

The present application includes and contemplates combinations of features and elements known to those of ordinary skill in the art. The embodiments, features and elements disclosed in this application may also be combined with any conventional features or elements to form a unique inventive concept as defined by the claims. Any feature or element of any embodiment may also be combined with features or elements from other inventive aspects to form yet another unique inventive aspect, as defined by the claims. Thus, it should be understood that any of the features shown and/or discussed in this application may be implemented alone or in any suitable combination. Accordingly, the embodiments are not limited except as by the appended claims and their equivalents. Furthermore, various modifications and changes may be made within the scope of the appended claims.

Further, in describing representative embodiments, the specification may have presented the method and/or process as a particular sequence of steps. However, to the extent that the method or process does not rely on the particular order of steps set forth herein, the method or process should not be limited to the particular sequence of steps described. Other orders of steps are possible as will be understood by those of ordinary skill in the art. Therefore, the particular order of the steps set forth in the specification should not be construed as limitations on the claims. Further, the claims directed to the method and/or process should not be limited to the performance of their steps in the order written, and one skilled in the art can readily appreciate that the sequences may be varied and still remain within the spirit and scope of the embodiments of the present application.

Claims

1. An environment sensing device, comprising:

a host, comprising:

the shell comprises a base and a shell body, wherein the base is used for being rotationally connected with a body of an automobile;

the sensor assembly is arranged on one side of the base and used for acquiring environmental information; the driving mechanism is used for driving the base to rotate;

2. The environmental sensing device of claim 1, wherein the housing further comprises a shaft extending from a side of the base;

the driving mechanism comprises a motor and a transmission mechanism;

3. The environment sensing device of claim 2, wherein the transmission is a gear transmission, a belt transmission, or a chain transmission.

4. The environment sensing device of claim 2, wherein the primary axis is parallel to the rotation axis;

5. The environmental sensing device of claim 4, wherein the pivot shafts extend from opposite sides of the base;

6. The environment sensing device according to claim 2, further comprising a first support for connecting the vehicle body, wherein the first support is provided with a first shaft hole in clearance fit with the rotating shaft.

7. The environmental sensing device of claim 6, wherein the pivot shafts extend from opposite sides of the base;

8. The environmental sensing device according to any one of claims 1 to 7, wherein the base is configured as a plate-like structure.

9. The environment sensing device of claim 8, wherein the housing comprises a protective shell disposed on a surface of the base, the housing and the protective shell defining a cavity for receiving the sensor assembly.

10. The device as claimed in claim 9, wherein the protective shell is detachably connected to the base.

11. The environmental sensing device of claim 9, wherein the protective shell is provided with a light-transmissive window.

12. The environmental awareness apparatus of claim 11, wherein the housing further comprises a light-transmitting plate covering the light-transmitting window, and a water chute recessed into the housing is disposed at an edge of the light-transmitting plate.

13. The environment sensing device of any one of claims 1 to 7, wherein the sensor assembly comprises a vision sensor, a lidar, a millimeter wave radar, and/or an ultrasonic radar.

14. The environment sensing apparatus of claim 13, wherein the lidar is a solid-state lidar.

15. An automobile, characterized by comprising the environment sensing apparatus according to any one of claims 1 to 14 and a vehicle body;

the base is rotatably connected to the vehicle body.

16. The automobile of claim 15, wherein the body includes a roof, the roof being provided with a mounting opening;

the base is disposed in the mounting opening.

17. The vehicle of claim 16, wherein the mounting opening is disposed at a front end of the roof.

18. The vehicle of claim 16, wherein the environmental awareness apparatus further comprises a seal disposed between the inner wall of the mounting opening and the side of the base for closing a gap between the base and the inner wall of the mounting opening.