CN221888164U

CN221888164U - Roller for moving cleaning robot

Info

Publication number: CN221888164U
Application number: CN202323198895.8U
Authority: CN
Inventors: A·德舍纳; E·阿玛劳
Original assignee: iRobot Corp
Current assignee: iRobot Corp
Priority date: 2022-11-28
Filing date: 2023-11-24
Publication date: 2024-10-25
Anticipated expiration: 2033-11-24
Also published as: CN221903477U; WO2024118179A1; US20240172906A1

Abstract

A roller for a mobile cleaning robot may include a roller core, a first elongated member, a second elongated member, and a spacer. The roll core may extend along a longitudinal axis of the roll. The first elongate member may be engaged with the floor surface. The first elongated member may at least partially surround the first portion of the roll core. The second elongate member may also engage the floor surface. The second elongated member may at least partially surround the second portion of the roll core. The spacer may at least partially surround the roll core between the first elongated member and the second elongated member. The spacer may be engaged with the floor surface and may be configured to prevent debris from collecting between the first elongate member and the second elongate member.

Description

Roller for moving cleaning robot

Technical Field

Embodiments described herein relate generally to mobile cleaning robots, and more particularly, to mobile cleaning robots with spacers.

Background

Autonomous mobile robots include autonomous mobile cleaning robots that can perform cleaning tasks autonomously in an environment such as home. Autonomous mobile cleaning robots can navigate across a floor surface and avoid obstacles while simultaneously sucking dust to the floor surface and manipulating rotatable members carried by the robot to ingest debris from the floor surface. As the robot moves across the floor surface, the robot may rotate a rotatable member, which may engage and direct debris to a vacuum airflow generated by the robot. Thus, the rotatable member and the vacuum airflow may cooperate to allow the robot to ingest debris.

Disclosure of utility model

Autonomous mobile cleaning robots may be used to automatically or autonomously clean a portion of an environment, such as one or more rooms, by extracting debris from the surface of the one or more rooms. The extraction can be performed using a single roller. The blades of a single roller may be configured in a chevron pattern, with the blades on opposite sides of the roller having opposite pitches or helices. Such a roller with a chevron pattern may provide improved cleaning performance. The inventors have recognized that there is a particular need for a single roller that provides the advantages of a chevron pattern while also providing reduced noise and power consumption.

In certain systems including a herringbone patterned roll, the inventors have recognized that improved noise performance and power consumption may be provided by replacing the central portion of the herringbone roll with a spacer.

The present disclosure describes devices and methods that may help solve this problem, for example, by including a roller that may include a first elongated member, a second elongated member, and a spacer. The first elongate member, the second elongate member, and the spacer are each engageable to a surface of the environment. The first and second elongate members may comprise a spiral pattern or a chevron pattern to assist in extracting debris from the environmental surface. The spacer may prevent debris from collecting between the first elongate member and the second elongate member.

For example, a mobile cleaning robot may include a roll core, a first elongated member, a second elongated member, and a spacer. The roll core may extend along a longitudinal axis of the roll. The first elongate member may be engaged with the floor surface. The first elongated member may at least partially surround the first portion of the roll core. The second elongate member may also engage the floor surface. The second elongated member may at least partially surround the second portion of the roll core. The spacer may at least partially surround the roll core between the first elongated member and the second elongated member. The spacer may be engaged with the floor surface and may be configured to prevent debris from collecting between the first elongate member and the second elongate member.

Drawings

In the drawings, which are not necessarily drawn to scale, like numerals may describe similar components in different views. The same numbers with different letter suffixes may represent different instances of similar components. The drawings illustrate generally, by way of example, and not by way of limitation, the various embodiments discussed in the present document.

Fig. 1A shows a bottom view of a mobile cleaning robot.

Fig. 1B shows a cross-sectional view of a mobile cleaning robot.

Fig. 2 shows a perspective view of an example of a roller.

Fig. 3 shows a perspective view of an example of a roller.

Fig. 4 shows an enlarged perspective view of an example of a roller.

Fig. 5 shows a perspective view of an example of a spacer.

Fig. 6 shows a top view of an example of a spacer.

Fig. 7 shows a side view of an example of a spacer.

Fig. 8 shows a perspective view of an alternative example of a roller.

FIG. 9 illustrates a block diagram that shows an example of a machine upon which one or more embodiments may be implemented.

Detailed Description

Autonomous mobile cleaning robots may be used to automatically or autonomously clean a portion of an environment, such as one or more rooms, by extracting debris from the surfaces of the one or more rooms. The extraction can be performed using a single roller. The use of a single roller may allow the roller design to help reduce the amount of energy required during a cleaning operation as compared to a two roller design. In an example, a single roller may include different patterns to aid in extracting debris, such as fiber debris and particle debris, from a floor surface.

For example, the first and second elongated members may each include one or more wings (or blades) extending longitudinally along the longitudinal axis of the roller in a helical pattern. In another example, the first and second elongated members may include one or more wings extending longitudinally along the longitudinal axis of the roller in a chevron pattern. In a chevron pattern, the spiral pattern on the first elongated member may rotate about the roll core in an opposite direction to the spiral pattern on the second elongated member. In an example, during operation, a roller having a first elongated member and a second elongated member may generate more noise than desired and may require additional power to rotate the roller, the first elongated member and the second elongated member having opposite helical patterns (or chevron patterns) and forming a single body.

Thus, the first and second elongate bodies may be separated from each other such that the first and second elongate bodies may deflect independently of each other. However, as the first and second elongate bodies deflect, a gap may form between the first and second elongate bodies. The gap between the first and second elongated bodies can reduce the efficiency of debris extraction and can create a sink where fiber debris wraps around the roller.

The present disclosure describes devices and methods that can help address these problems, for example, by providing a mobile cleaning robot that includes a roller having a first elongated member, a second elongated member, and a spacer. In an example, the spacer may be mounted on the roll core between the first elongated member and the second elongated member. The diameter of the spacer may be less than the resting (resting) diameter of the first and second elongate members to help reduce stress in the middle of the roller when the roller is operatively rotated and contacts the floor. The smaller diameter helps to reduce the amount of power to operate the roller. Further, the spacer may at least partially fill an axial gap between the first and second elongate members, which may help limit debris accumulation between the first and second elongate members. Further, the spacer may transfer debris between the first elongate member and the second elongate member.

Fig. 1A shows a bottom view of the mobile cleaning robot 100. Fig. 1B shows a cross-sectional view of the mobile cleaning robot 100 in an environment 40. Fig. 1A and 1B will be discussed together below. Fig. 1A shows a section indicated by 1B-1B, and fig. 1B also shows directional arrows F and R.

The cleaning robot 100 may include a housing or body 102, a cleaning assembly 104, and a control system 106 (which may include a controller 108 and a memory 110). The cleaning robot 100 may also include a drive wheel 112, a motor(s) 114, and one or more support skids (skids) 116. The cleaning assembly 104 can include a cleaning inlet 117, a roller 118 (or cleaning wheel), a vacuum system 119, a roller motor 120, and a dustpan 122 (or guide). The robot 100 may also include cliff sensors 124, proximity sensors 126, bumpers 128, collision sensors 130, obstacle following sensors 132, and brushes 134 (or side brushes 134) including motors 136.

The housing 102 may be a rigid or semi-rigid structure constructed of one or more materials such as metal, plastic, foam, elastomer, ceramic, composite, combinations thereof, and the like. The housing 102 may be configured to support various components of the robot 100, such as the wheel 112, the controller 108, the cleaning assembly 104, the dustpan 122, and the side brushes 134. The housing 102 may define a structural periphery of the robot 100. In some examples, the housing 102 includes a chassis, a cover, a base plate, and a bumper assembly. Because the robot 100 may be a home robot, the robot 100 may have a small outline so that the robot 100 may be adapted to be under furniture in a home.

The roller 118 of the cleaning assembly 104 may be rotatably connected to the housing 102 near the cleaning inlet 117 (optionally in a front portion of the robot 100), wherein the roller 118 may extend horizontally across the robot 100. The roller 118 may be coupled to a roller motor 120 to be driven to rotate the roller 118 relative to the housing 102 to facilitate collection of dust and debris from the environment 40 through the cleaning inlet 117. The vacuum system 119 may include a fan or impeller and a motor operable by the controller 108 to control the fan to generate an air flow that passes through the cleaning inlet 117 between the rollers 118 and into the dustbin 138 (shown in fig. 1B).

The rollers 118 may be of several types, such as when the rollers 118 are optimized based on the environment 40, as discussed further below. The rollers 118 may include bristles or brushes that may effectively separate (or agitate) debris within the carpet fibers for aspiration by the robot 100. The rollers 118 may also include blades, wings, or flexible members extending therefrom that can relatively effectively separate debris within the carpet fibers for aspiration by the robot 100, while also effectively stripping the debris from hard surfaces. The roller 118 may also include tabs, blades, or bristles that are effective to strip debris from hard surfaces. In other examples, the rollers 118 may be other types of rollers.

The controller 108 may be located within the housing and may be a programmable controller such as a single or multi-board computer, a Direct Digital Controller (DDC), a Programmable Logic Controller (PLC), or the like. In other examples, the controller 108 may be any computing device, such as a handheld computer, for example, a smart phone, tablet, notebook, desktop computer, or any other computing device that includes a processor, memory, and communication capabilities. Memory 110 may be one or more types of memory such as volatile or nonvolatile memory, read Only Memory (ROM), random Access Memory (RAM), magnetic disk storage media, optical storage media, flash memory devices, and other storage devices and media. The memory 110 may be located within the housing 102 and connected to the controller 108 and accessible by the controller 108.

For example, the control system 106 may also include a sensor system having one or more electrical sensors. As described herein, the sensor system may generate a signal indicative of the current position of the robot 100, and may generate a signal indicative of the position of the robot 100 as the robot 100 travels along the floor surface 50. The controller 108 may also be configured to execute instructions to perform one or more operations described herein.

The drive wheel 112 may be supported by the body 102 of the robot 100, may be partially located within the housing 102, and may extend through a bottom portion of the housing 102. Wheel 112 may also be connected to the shaft and may rotate with the shaft; the wheels 112 may be configured to be driven by motors 114 to propel the robot 100 along the surface 50 of the environment 40, wherein the motors 114 may be in communication with the controller 108 to control such movement of the robot 100 in the environment 40.

The skid 116 may be a low friction element connected to the body 102 of the robot and may be a passive body configured to help balance the robot 100 within the environment 40. The drive wheel 112 and skid(s) 116 may cooperate together to support the housing 102 above the floor surface 50. For example, one skid 116 may be located in the rear portion of the housing 102 and the drive wheel 112 may be located in front of the skid 116. In another example, the cleaning robot 100 may include two wheels 112 and include casters to aid in balancing the cleaning robot 100.

The dustpan 122 may be connected to the body 102 and may engage the floor surface 50 (as shown in FIG. 1B) to help direct debris 5 from the environment 40 to a suction duct 139 for collection in a collection bin 138. The roller 118 may also engage with the dustpan 122 to direct the debris 75 to the suction duct 139. As discussed in further detail below, the dustpan 122 may be actively or passively retracted to help improve the mobility of the robot 100.

Cliff sensor 124 may be positioned along a bottom portion of housing 102. Each cliff sensor 124 may be an optical sensor that may be configured to detect the presence or absence of an object (such as floor surface 50) below the optical sensor. Cliff sensor 124 may be connected to controller 108. The proximity sensor(s) 126 may be located near a front portion of the housing 102. In other examples, the proximity sensor 126 may be located in other portions of the housing 102. The proximity sensor 126 may include an optical sensor facing outward from the housing 102 and may be configured to generate a signal based on the presence or absence of an object in front of the optical sensor. The proximity sensor 126 may be connected to a controller.

The bumper 128 may be removably secured to the housing 102 and may be movable relative to the housing 200 when mounted to the body 102. In some examples, the bumper 128 may form a portion of the housing 102. The crash sensor 130 may be coupled to the housing 102 and may be engaged or configured to interact with the bumper 128. The collision sensor 130 may include a beam break sensor, a capacitive sensor, a switch, or other sensor that may detect contact between the robot 100 (i.e., the bumper 128) and an object in the environment 40. The collision sensor 130 may be connected to the controller 108.

The robot may optionally include an image capture device, which may be a camera connected to the housing 102. The image capture device may be configured to generate a signal based on an image of the environment 40 of the robot 100 as the robot 100 moves around the floor surface 50.

The obstacle follower sensor 132 may include an optical sensor facing outwardly from a side surface of the housing 102 and may be configured to detect the presence or absence of an object adjacent to the side surface of the housing 102. The obstacle following sensor 132 may horizontally emit a light beam in a direction perpendicular to the forward driving direction F of the robot 100. In some examples, at least some of the proximity sensor 126 and the obstacle following sensor 132 may include an optical emitter and an optical detector. The optical emitter may emit a light beam outward (e.g., horizontally outward) from the robot 100, and the optical detector detects the reflection of the light beam reflected back from objects in the vicinity of the robot 100. The robot 100, for example, using the controller 108, may determine the reflected intensity (or alternatively, the time of flight of the beam) and thus the distance between the optical detector and the object, and thus the distance between the robot 100 and the object.

The brush 134 may be connected to the underside of the robot 100 and may be connected to a motor 136, the motor 144 being operable to rotate the side brush 134 relative to the housing 102 of the robot 100. The side brushes 134 may be configured to engage the debris to move the debris toward the cleaning assembly 104 or away from the edge of the environment 40. A motor 136 configured to drive the side brush 134 may be in communication with the controller 108.

In some example operations, the robot 100 may be propelled in a forward drive direction or a backward drive direction. The robot 100 may also be propelled such that the robot 100 rotates in place or simultaneously with moving in the forward or rearward driving direction.

The controller 108 may execute software stored on the memory 110 to cause the robot 100 to perform various navigational and cleaning activities by operating the various motors of the robot 100. For example, when the controller 108 causes the robot 100 to perform a task, the controller 108 may operate the motors 114 to drive the wheels 112 and propel the robot 100 along the floor surface 50. Further, the controller 108 may operate the motor 120 to rotate the roller 118, may operate the motor 136 to rotate the brush 134, and may operate the motor of the vacuum system 119 to generate an air flow.

The roller 118 may rotate about an axis (as shown in fig. 1B) to contact the floor surface 50 as the rotatable member 118 rotates relative to the housing 102, thereby agitating the debris 75 on the floor surface 50. The rotatable member 118 agitates the debris 75 on the floor surface to direct the debris 75 from the cleaning inlet 117 to a suction duct 139 (shown in fig. 1B) and into a debris bin 138 within the robot 100. The vacuum system 119 may cooperate with the cleaning assembly 104 to draw debris 75 from the floor surface 50 into a debris bin 138. In some cases, the air flow generated by the vacuum system 119 may generate sufficient force to draw debris 75 on the floor surface 50 upward through the suction conduit 139 and into the debris bin 138. The brush 134 may be rotated about a non-horizontal axis such that debris on the floor surface 50 is brushed into the cleaning path of the cleaning assembly 104 as the robot 100 moves.

Various sensors of the robot 100 may be used to assist the robot in navigating and cleaning within the environment 40. For example, the cliff sensor 124 may detect obstacles such as a steep drop and a cliff below a portion of the robot 100 where the cliff sensor 124 is disposed. Cliff sensor 124 may transmit a signal to controller 108 such that controller 108 may redirect robot 100 based on the signal from cliff sensor 124. The proximity sensor 126 may generate a signal based on the presence or absence of an object in front of the optical sensor. For example, the detectable objects include obstructions in the environment 40 of the robot 100, such as furniture, walls, people, and other objects. The proximity sensor 126 may transmit a signal to the controller 108 such that the controller 108 may redirect the robot 100 based on the signal from the proximity sensor 126.

In some examples, the collision sensor 130 may be used to detect movement of the bumper 128 of the robot 100. The collision sensor 130 may transmit a signal to the controller 108 such that the controller 108 may redirect the robot 100 based on the signal from the collision sensor 130. In some examples, the obstacle follower sensor 132 may detect obstacles such as detectable objects including furniture, walls, people, and other objects in the environment of the robot 100. In some embodiments, the sensor system may include an obstacle following sensor along the side surface, and the obstacle following sensor may detect the presence or absence of an object adjacent to the side surface. One or more obstacle following sensors 132 may also be used as obstacle detection sensors, e.g., similar to the proximity sensors described herein.

The robot 100 may also include a sensor for tracking the distance traveled by the robot 100. For example, the sensor system may include an encoder associated with the motor 114 for the drive wheel 112, and the encoder may track the distance the robot 100 has traveled. In some embodiments, the sensor may comprise an optical sensor facing downward toward the floor surface. The optical sensor may be positioned to direct light through the bottom surface of the robot 100 toward the floor surface 50. The optical sensor may detect the reflection of light and may detect the distance traveled by the robot 100 based on a change in floor characteristics as the robot 100 travels along the floor surface 50.

The controller 108 may use data collected by the sensors of the sensor system to control the navigational behavior of the robot 100 during the mission. For example, the controller 108 may use sensor data collected by obstacle detection sensors (cliff sensor 124, proximity sensor 126, and collision sensor 130) of the robot 100 to enable the robot 100 to avoid obstacles within the environment of the robot 100 during a mission.

The sensor data may be used by the controller 108 for simultaneous localization and mapping (SLAM) techniques in which the controller 108 extracts features of the environment represented by the sensor data and builds a map of the floor surface 50 of the environment. The sensor data collected by the image capture device may be used in techniques such as vision-based SLAM (VSLAM) in which the controller 108 extracts visual features corresponding to objects in the environment 40 and uses those visual features to construct a map. As the controller 108 guides the robot 100 around the floor surface 50 during performance of a task, the controller 108 uses SLAM techniques to determine the position of the robot 100 in the map by detecting features represented in the collected sensor data and comparing those features to previously stored features. The map formed from the sensor data may indicate locations within the environment that are traversable and non-traversable spaces. For example, the position of an obstacle may be indicated on a map as a traversable space, and the position of an open floor space may be indicated on a map as a traversable space.

Sensor data collected by any sensor may be stored in memory 110. In addition, other data generated for SLAM technology, including map data forming a map, may be stored in the memory 110. The data generated during a task may include persistent data generated during the task that may be used in another task. In addition to storing software for causing the robot 100 to perform its actions, the memory 110 also stores sensor data or data resulting from the processing of the sensor data for access by the controller 108. For example, the map may be a map that may be used and updated by the controller 108 of the robot 100 from task to navigate the robot 100 around the floor surface 50.

Fig. 2 shows a perspective view of an example of a roller 200. The roller 200 may be used with any mobile cleaning robot, such as the robot 100, to increase the cleaning capacity of the robot. As described above, an autonomous mobile cleaning robot may be used to automatically or autonomously clean one or more rooms by extracting debris from surfaces of a portion of an environment, such as the one or more rooms. Extraction may be performed using a single roller (e.g., roller 200). The blades of a single roller may be configured in a chevron pattern, with the blades on opposite sides of the roller having opposite pitches or helices. Such a roller with a chevron pattern may provide improved cleaning performance.

Fig. 3 shows a perspective view of an example of a roller 300, such as roller 118 of fig. 1A and 2. The roller 300 may engage the surface 50 of the environment 40 (as shown in fig. 1A) to extract debris from the surface 50. The roller 300 may be an elongated body and may be operable to rotate about a longitudinal axis LA. The roller 300 may include a roller core 310, a first elongate member 320, a second elongate member 330, and a spacer 340.

The roll core 310 may extend along a longitudinal axis LA of the roll 300. The roll core 310 may couple the roll 300 to the mobile robot 100 (fig. 1A and 2). The roll core 310 may also provide radial support for the roll 300 when the roll 300 is engaged with the surface 50 (fig. 1A). In an example, the roll core 310 may be operably connected at one end to one or more motors (e.g., the roll motor 120 in fig. 1A) to rotate the roll 300 about the longitudinal axis LA, and may be supported at an opposite end by bearings. The roll core 310 may be made of one or more of polymers, metals, foams, ceramics, composites, alloys, and the like.

The first elongate member 320 can be engaged with a floor surface, such as surface 50 in fig. 1A. The first elongated member 320 may at least partially surround the first portion 312 of the roll core 310. In an example, the first elongate member 320 can be a monolithic polymer or rubber. In another example, the first elongate member 320 can be made of a combination or composite of polymers, rubber, metals, and the like.

The second elongate member 330 can be engaged with a floor surface, such as surface 50. The second elongated member 330 may at least partially surround the second portion 314 of the roll core 310. In an example, the second elongate member 330 can be a monolithic polymer or rubber. In another example, the second elongate member 330 can be made of a combination or composite of polymers, rubber, metals, and the like. In an example, the first and second elongate members 320, 330 may be configured to contact the floor surface simultaneously as the mobile cleaning robot cleans the floor surface. In another example, the first and second elongate members 320, 330 may be configured to contact a floor surface under different conditions. For example, the first and second elongate members 320, 330 may be designed to alternately contact a floor surface.

As shown in fig. 3, the first and second elongated members 320, 330 may be axially spaced from one another on the roll core 310. The spacing between the first and second elongated members 320, 330 may help reduce noise generation by the roller 300 and may help reduce the power required to operate the roller 300. However, gaps between the first and second elongate members 320, 330 may result in loss of debris, such as particulate debris within the first or second elongate members 320, 330 or particulate debris between the first or second elongate members 320, 330. For example, particulate debris on the floor surface between the first and second elongated members 320, 330 may be missed by the roller 300. Further, particulate debris within the first elongate member 320 or the second elongate member 330 may fall into the gap and disengage from the first elongate member 320 or the second elongate member 330, respectively. The gap between the first and second elongate members 320, 330 may also create a void that may trap fiber fragments and cause entanglement of the fiber fragments, such as hair, threads, other fiber fragments, and the like. To reduce the gap between the first and second elongate members 320, 330 and to help reduce loss of particulate debris and accumulation of fiber debris between the first and second elongate members 320, 330, a spacer 340 may be mounted between the first and second elongate members 320, 330.

The spacer 340 may at least partially surround the roll core 310 and may engage a floor surface, such as surface 50. The spacer 340 may prevent the roller 300 from losing particulate debris by engaging the particulate debris between the first and second elongate members 320, 330 (e.g., lifting or flicking toward the dustpan) and by preventing the particulate debris within the first or second elongate members 320, 330 from escaping into the gap between the first and second elongate members 320, 330. The spacer 340 may also guide or shuttle the fiber fragments between the first and second elongate members 320, 330 to prevent the fiber fragments from collecting or becoming entangled in the gap between the first and second elongate members 320, 330. The spacer 340 may be made of foam, polymer, rubber, or any combination thereof, or the like. In another example, the spacer 340 may include bristles. In an example, the length of the bristles may be adjusted based on the diameter of the bristles. For example, if the bristles have a larger diameter, the bristles may be longer and still have sufficient stiffness to move the particle fragments. For example, the bristles may have sufficient stiffness to lift the particle fragments from the floor surface or to brush the particle fragments toward the dustpan. In another example, the bristles may have a smaller diameter and a shorter length to have sufficient stiffness to move the debris. For example, the shorter bristles may have sufficient stiffness to lift the particle fragments from the floor surface or to flick the particle fragments toward the dustpan.

Fig. 4 shows an enlarged perspective view of an example of a roller 300. The first elongate member 320 may include a first armature (shell) 402, a first wing (or blade, hereinafter first wing 404), and a second wing (or blade, hereinafter second wing 406). The first armature 402 may extend the entire length of the first elongate member 320. In another example, the first armature 402 may extend a portion of the length of the first elongate member 320. The first wing 404 can extend radially outward from the first armature 402. The first wing 404 can extend along at least a portion of the longitudinal axis LA. The second wing 406 may also extend radially outward from the first armature 402. The second wing 406 can extend at least part of the longitudinal axis LA. The first wing 404 and the second wing 406 can be made of a polymer, foam, metal, ceramic, rubber, any combination thereof, and the like. In an example, the first armature 402, the first wing 404, and the second wing 406 may be made of the same material. In another example, the first armature 402, the first wing 404, and the second wing 406 may be made of different materials. In yet another example, the first armature 402 may be made of a first material and the first wing 404 and the second wing 406 may be made of a second material. In an example, the first wing gap 408 can be between 2 millimeters and 10 millimeters. In another example, the first wing gap 408 can be between 3 millimeters and 5 millimeters.

The first wing 404 and the second wing 406 can extend around the first elongate member 320, such as in a spiral pattern. The first and second wings 404, 406 may be circumferentially spaced apart from each other to define a first wing gap 408 therebetween.

The first wing gap 408 can assist in extracting debris from the floor surface. For example, the first wing gap 408 can be or can define at least a portion of a void in the first elongate member 320 that can allow debris to be collected and distributed therein. As such, the extension of the first wing 404 and the second wing 406 along the first skeleton 402 may help guide debris within the first wing gap 408 along the first elongate member 320 and toward a cleaning inlet, such as the cleaning inlet 117 in FIGS. 1A and 2. The extension of the first wing gap 408 and the first and second wings 404, 406 along the first armature 402 may also help to disperse debris on the floor surface.

The first wing gap 408 can also help allow flexibility of the first wing 404 and the second wing 406. For example, the first wing gap 408 is spaced apart such that the first wing 404 and the second wing 406 are able to deflect when in contact with a floor surface. The deflection of the first wing 404 and the second wing 406 can assist the first elongate member 320 in extracting debris from a variety of different floor surfaces.

The second elongate member 330 may include a second backbone 412, a third wing (or blade, hereinafter third wing 414), and a fourth wing (or blade, hereinafter fourth wing 416). The second backbone 412 can extend the entire length of the second elongate member 330. In another example, the second armature 412 may extend a portion of the length of the second elongate member 330. Third wing 414 may extend radially outward from second armature 412. The third wing 414 may also extend along at least a portion of the longitudinal axis LA. Fourth wing 416 may extend radially outward from second backbone 412. The fourth wing 416 may also extend along at least a portion of the longitudinal axis LA. The third airfoil 414 and the fourth airfoil 416 may be circumferentially spaced apart from each other to define a second airfoil gap 418 therebetween. The second armature 412, third wing 414, and fourth wing 416 may be made of a polymer, foam, metal, ceramic, rubber, any combination thereof, and the like. In an embodiment, the second armature 412, the third wing 414, and the fourth wing 416 may be made of the same material. In another example, the second armature 412, the third wing 414, and the fourth wing 416 may be made of different materials. In yet another example, the second armature 412 may be made of a first material and the third wing 414 and the fourth wing 416 may be made of a second material.

The second wing gap 418 can help the second elongate member 330 extract debris and help the third wing 414 and the fourth wing 416 to be malleable in the same manner as described above (i.e., the first wing gap 408 can help the first elongate member 320).

In one example, the first and second wings 404 and 406 of the first elongate member 320 and the third and fourth wings 414 and 416 of the second elongate member 330 may deflect radially inward and tangentially when in contact with a floor surface. When any of the first wing 404, the second wing 406, the third wing 414, or the fourth wing 416 is deflected from engagement with the floor surface, the first wing 404, the second wing 406, the third wing 414, or the fourth wing 416 together may define a deflection diameter 420 (as shown in fig. 1B) at a maximum deflected position.

Deflection of the wings (e.g., first wing 404, second wing 406, third wing 414, and fourth wing 416) may help the mobile cleaning robot extract debris from the environmental surface, as deflection may increase the contact force between the wings and debris to help extract debris from the environmental surface and lift the debris into the wing gaps (e.g., first wing gap 408 and second wing gap 418). When the wings, e.g., first wing 404, second wing 406, third wing 414, and fourth wing 416, deflect radially inward and tangentially, the wings develop potential energy that may also help lift the particulate debris as roller 300 rotates, and then decompress toward equilibrium because the wings no longer contact the floor surface. When the mobile cleaning robot engages with the large particle fragments, the large particle fragments may deflect the first wing 404, the second wing 406, the third wing 414, or the fourth wing 416 to increase potential energy within the wings and aid in extracting the large particle fragments by flicking or lifting the large particle fragments from the floor surface. Any of the first wing 404, the second wing 406, the third wing 414, or the fourth wing 416 can extract debris from the floor surface and direct the debris toward a dustpan, such as the dustpan 122 of FIG. 1A. In an example, a floor surface or particle fragment may contact the first wing 404 and deflect the first wing 404 toward the second wing 406. Directing the first wing 404 toward the second wing 406 can direct debris toward the first wing gap 408. As the roller 300 rotates, debris collected in the first wing gap 408 can be directed by the first wing 404 and the second wing 406 toward the dustpan.

In another example, the floor surface or particle fragment may contact the third wing 414 and deflect the third wing 414 toward the fourth wing 416. The third wing 414 deflected toward the fourth wing 416 may direct debris toward the fourth wing 416. As the roller 300 rotates, the debris collected in the first wing gap 408 and the second wing gap 418 may be directed (e.g., lifted or flicked) toward the dustpan by the second wing 406 and the fourth wing 416, respectively.

When the first wing 404, the second wing 406, the third wing 414, and the fourth wing 416 deflect, a gap is formed between the first elongate member 320 and the second elongate member 330. The gap between the first and second elongate members 320, 330 increases noise during robot operation, provides a collection area for fiber debris between the first and second elongate members 320, 330, and reduces extraction of debris at the center of the roller 300. In this way, the spacer 340 may be installed between the first and second elongated members 320, 330 to reduce noise of the roller 300, prevent fiber debris from collecting between the first and second elongated members 320, 330, and prevent debris from escaping from the roller 300 between the first and second elongated members 320, 330.

The spacer 340 will be discussed in more detail with reference to fig. 5-7. Fig. 5 shows a perspective view of an example of a spacer 340. Fig. 6 shows a top view of an example of a spacer 340. Fig. 7 shows a side view of an example of a spacer 340. The spacer 340 may include a base 426 and a body 430. The body 430 may include a first outer surface 432 and a second outer surface 434. The first surface 432 may be opposite the second surface 434 on the body 430. The body 430 may also include a plurality of fins including first fins 436A-436N and second fins 438A-438N. In an example, the body 430 may also include any shape that extends from the body 430 to prevent fiber fragments from wrapping around the roller 300 between the first and second elongated members 320, 330. For example, bristles, wires, etc. may extend from the body 430 to reduce a gap between the first and second elongate members 320, 330 that results from deflection of any portion of the first or second elongate members 320, 330.

The base 426 may be connected to the roll core 310 at a radially inner surface of the base 426. The base 426 may extend circumferentially around the roll core 310 and radially outward from the roll core 310. In an example, the base 426 may be integral with the roll core 310. In an example, the base 426 may be connected to the roll core 310 to secure the spacer 340 to the roll core 310. The base 426 may be made of plastic, polymer, metal, rubber, foam, ceramic, alloy, any combination thereof, and the like.

Body 430 may extend circumferentially around base 426. Body 430 may also extend radially outward from base 426. The body 430 may be configured to limit debris from accumulating between the first and second elongate members 320, 330. Thus, the body 430 may fill the entire gap (or at least a portion of the gap) between the first and second elongate members 320, 330. Body 430 may be integrated into base 426 such that base 426 and body 430 are one unitary, integral component. In an example, the base 426 and the body 430 may be separate components, and the body 430 may be connected to the base 426. The body 430 may be made of plastic, polymer, foam, ceramic, metal, rubber, any combination thereof, and the like. The body 430 may be made of the same material as the base 426. In another example, the body 430 may be made of a different material than the base 426.

The first fin 436 may extend axially from the first surface 432 of the body 430. The first fin 436 may also extend axially from the second surface 434 such that the first fin 436 may extend at least partially into the first fin gap 408 from the first surface 432 and the second surface 434 (as shown in fig. 4). The first fin 436 may also extend radially outward from the base 426 to the outer periphery of the body 430 at an angle such that the first fin 436 at the base 426 may be circumferentially spaced from the first fin 436 at the periphery of the body 430.

The second fin 438 may extend axially from the first surface 432 of the body 430. The second fin 438 may also extend axially from the second surface 434 such that the second fin 438 may extend at least partially into the second fin gap 418 from the first surface 432 and the second surface 434 (as shown in fig. 4). The second fins 438 may also extend radially outward from the base 426 to the outer periphery of the body 430 at an angle such that the second fins 438 at the base 426 may be circumferentially spaced from the second fins 438 at the periphery of the body 430.

The first fin 436 and the second fin 438 may define a maximum curvature of the first fin 404, the second fin 406, the third fin 414, or the fourth fin 416. Further, the first fin 436 and the second fin 438 may help support the first fin 404, the second fin 406, the third fin 414, and the fourth fin 416 as the first fin 404, the second fin 406, the third fin 414, and the fourth fin 416 deflect from the floor surface. Thus, the first fin 436 and the second fin 438 may help prevent plastic deformation of the first fin 404, the second fin 406, the third fin 414, and the fourth fin 416.

In an example, the spacer 340 may include a major diameter 440 such that the spacer 340 may be within the major diameter 440. The major diameter 440 of the spacer 340 may be less than or equal to the deflection diameter 420. In yet another example, the major diameter 440 of the spacer 340 may be slightly larger than the deflection diameter 420.

As shown in fig. 3 and 4, the first wing 404 and the second wing 406 may extend away from the spacer 340 in a first helical pattern, and the third wing 414 and the fourth wing 416 may extend away from the spacer 340 in a second helical pattern. In an example, the first spiral pattern may be symmetrical with the second spiral pattern about the spacer 340, forming a chevron pattern across the first and second elongate members 320, 330. In another example, the first wing 404 and the second wing 406 may extend symmetrically away from the spacer 340 in any pattern. For example, the first wing 404 and the second wing 406 may extend horizontally from the spacer 340.

Fig. 8 shows a perspective view of an alternative example of a roller 800, such as roller 118 in fig. 1A and 2 or roller 300 in fig. 3 and 4. Roller 800 may engage surface 50 of environment 40 (as shown in fig. 1A) to extract debris from surface 50. The roller 800 may be an elongated body and may be operable to rotate about a longitudinal axis LA. The roller 800 may include a roller core 810, a first elongated member 820, a second elongated member 830, and a spacer 840.

As shown in fig. 8, the spacers 840 may include bristles extending from the roll core 810. As described above, the spacer 840 may perform the same function as the spacer 340. As shown in fig. 8, spacers 840 may extend laterally within the first and second elongate members 820, 830 to help fill the gap between the first and second elongate members 820, 830 that is created when any portion of the first and second elongate members 820, 830 deflect during rotation of the roller 800. As shown in fig. 8, the bristles of the spacer 840 may also extend the entire length of the roller 800 along the first and second elongate members 320, 330.

Fig. 9 shows a schematic diagram of a method 900 according to at least one example of the present disclosure. The method 900 may be a method of operating a mobile cleaning robot having a spacer. More specific examples of this method 900 are discussed below. For convenience and clarity, the steps or operations of method 900 are shown in a particular order; many of the operations discussed can be performed in a different order or concurrently without materially affecting the other operations. The method 900 discussed includes operations performed by a plurality of different participants, devices, or systems. It should be appreciated that a subset of the operations discussed in method 900 may be attributed to a single participant, device, or system, which may be considered a separate, independent process or method.

At step 902, the method 900 may include operating a drive wheel, such as the drive wheel 112 of fig. 1A of the mobile cleaning robot, such as the robot 100 of fig. 1A and 2, to navigate the mobile cleaning robot around an environment (such as the surface 50 of the environment 40 of fig. 1B).

At step 904, the method 900 may include operating a cleaning assembly to ingest debris from an environmental surface, and to operate the mobile cleaning robot in a cleaning mode, the cleaning assembly may include a roller, such as roller 300 first shown in fig. 3, which may rotate relative to the body of the mobile cleaning robot and may engage the surface to direct the debris toward the suction catheter. The roll may include a roll core extending along a longitudinal axis of the roll. The first elongated member may circumferentially surround the first portion of the roll core. The second elongated member may circumferentially surround the second portion of the roll core. The spacer (e.g., spacer 340 in fig. 3-7) may at least partially circumferentially surround a roll core (e.g., roll core 310 first shown in fig. 3) between a first elongated member (e.g., first elongated member 320 shown in fig. 3 and 4) and a second elongated member (e.g., second elongated member 330 shown in fig. 3 and 4). The spacer may be engaged with the floor surface and may be configured to prevent debris from collecting between the first elongate member and the second elongate member.

At step 906, the method 900 may include preventing debris within the first elongate member and within the second elongate member from collecting between the first elongate member and the second elongate member. For example, the spacer may retain the debris within the first elongate member, thereby facilitating lifting of the debris within the first elongate member toward a dustpan, such as the dustpan 122 of fig. 1A and 2. The spacer may also retain debris within the second elongate member, thereby causing debris within the second elongate member to lift toward the dustpan.

At step 908, the method 900 may include directing debris wrapped around a first elongate member toward a second elongate member. At step 910, the method 900 may include directing debris wrapped around the second elongate member toward the first elongate member. For example, hair, strings, strands of hair, any elongated member that may be wrapped around a roller, etc. may be transferred over the spacer between the first elongated member and the second elongated member. Reducing the amount of wound debris that may collect between the first and second elongated members may reduce the time required to remove the wound debris and help maintain the debris extraction performance of the roller. For example, the wound debris may be collected towards the end of the roller core of either the first or second elongated member, such that the wound debris does not affect the performance of the mobile cleaning robot.

Additional comments and examples

The following non-limiting examples describe certain aspects of the present subject matter in detail to address challenges and provide benefits and the like discussed herein.

Example 1 is a roller for a mobile cleaning robot, the roller comprising a roller core extending along a longitudinal axis of the roller; a first elongate member engageable with the floor surface, the first elongate member at least partially surrounding a first portion of the roll core; a second elongate member engageable with the floor surface, the second elongate member at least partially surrounding a second portion of the roll core; and a spacer at least partially surrounding the roller core between the first and second elongated members, the spacer being engageable with the floor surface and configured to avoid debris from collecting between the first and second elongated members.

In example 2, the subject matter of example 1 includes, wherein the first elongate member includes a first armature; a first wing extending radially outwardly from the first backbone and along at least a portion of the longitudinal axis; and a second wing extending radially outwardly from the first backbone and extending at least a portion of the longitudinal axis, wherein the first and second wings are circumferentially spaced apart from each other to define a first wing gap therebetween.

In example 3, the subject matter of example 2 includes wherein the first wing and the second wing extend in a first helical pattern around the first elongate member.

In example 4, the subject matter of example 3 includes, wherein the second elongate member further includes a second armature; a third wing extending radially outwardly from the second backbone and along at least a portion of the longitudinal axis; and a fourth wing extending radially outwardly from the second backbone and along at least a portion of the longitudinal axis, wherein the third and fourth wings are circumferentially spaced apart from each other to define a second wing gap therebetween.

In example 5, the subject matter of example 4 includes wherein the third wing and the fourth wing extend from the spacer in a second spiral pattern, and wherein the second spiral pattern is symmetrical with the first spiral pattern about the spacer.

In example 6, the subject matter of examples 4-5 includes that the intermediate spacer includes a base connected to and extending circumferentially around the roll core and extending radially outward from the roll core; and a body extending circumferentially around the base and extending radially outward from the base.

In example 7, the subject matter of example 6 includes, wherein the body of the spacer further includes a first fin extending axially from the first surface of the body, the first fin also extending axially from the second surface of the body such that the first fin extends at least partially into the first fin gap from the first surface and the second surface; and a second fin circumferentially spaced from the first fin and extending axially from the first surface, the second fin also extending axially from the second surface such that the second fin extends at least partially into the second fin gap from the first surface and the second surface.

In example 8, the subject matter of example 7 includes wherein the first and second wings of the first elongate member and the third and fourth wings of the second elongate member compress radially inward under a condition that the first elongate member or the second elongate member contacts the floor, the first, second, third, and fourth wings together defining a deflection diameter at a maximum deflection position when any of the first, second, fourth wings deflects from engagement with the floor surface.

In example 9, the subject matter of example 8 includes, wherein the spacer includes a major diameter such that the spacer is within the major diameter, and wherein the major diameter of the spacer is less than or equal to the deflection diameter.

In example 10, the subject matter of examples 7-9 includes wherein the first surface of the body and the second surface of the body define a width of the body.

In example 11, the subject matter of example 10 includes wherein the width of the body is between 2 and 10 millimeters.

In example 12, the subject matter of examples 6-11 includes wherein the spacer includes a first portion and a second portion, wherein the first portion and the second portion are detachably coupled to one another.

In example 13, the subject matter of examples 6-12 includes wherein the body of the spacer includes a plurality of bristles extending radially outward from the body of the spacer.

Example 14 is a mobile cleaning robot comprising a main body comprising a suction catheter; and a cleaning assembly operable to ingest debris from an environmental surface, the cleaning assembly comprising a roller rotatable relative to the body and engageable with the surface to direct the debris toward the suction conduit, the roller comprising a roller core extending along a longitudinal axis of the roller; a first elongated member circumferentially surrounding a first portion of the roll core; a second elongated member circumferentially surrounding a second portion of the roll core; and a spacer at least partially circumferentially surrounding the roller core between the first and second elongated members, the spacer being engageable with the floor surface and configured to avoid debris from collecting between the first and second elongated members.

In example 15, the subject matter of example 14 includes, wherein the first elongate member includes a first armature; a first vane extending radially outwardly from the first backbone and extending along at least a portion of the longitudinal axis; and a second vane extending radially outwardly from the first backbone and along at least a portion of the longitudinal axis, wherein the first vane and the second vane are circumferentially spaced apart from each other to define a first vane gap therebetween.

In example 16, the subject matter of example 15 includes wherein the first and second vanes extend in a helical pattern around the first elongated member.

In example 17, the subject matter of example 16 includes, wherein the second elongate member further includes a second armature; a third vane extending radially outwardly from the second backbone and extending along at least a portion of the longitudinal axis; and a fourth vane extending radially outwardly from the second backbone and extending at least a portion of the longitudinal axis, wherein the third vane and the fourth vane are circumferentially spaced apart from each other to define a second vane gap therebetween.

In example 18, the subject matter of example 17 includes, wherein the spacer comprises: a base connected to the roll core and extending circumferentially around at least a portion of the roll core and extending radially outwardly from the roll core; and a body extending circumferentially around at least a portion of the base and radially outward from the base, and wherein the body includes a first surface extending circumferentially around the body; and a second surface extending circumferentially around the body and opposite the first surface.

In example 19, the subject matter of example 18 includes, wherein the body of the spacer further includes a first fin extending axially from the first surface, the first fin also extending axially from the second surface such that the first fin extends at least partially into the first blade gap from the first surface and the second surface; and a second fin circumferentially spaced from the first fin and extending axially from the first surface, the second fin also extending axially from the second surface such that the second fin extends at least partially into the second blade gap from the first surface and the second surface.

In example 20, the subject matter of example 19 includes wherein, with the first elongate member or the second elongate member contacting the surface of the environment, the first and second blades of the first elongate member and the first and second blades of the second elongate member compress radially inward, the first, second, third, and fourth blades together defining a deflection diameter at a maximum deflection position when any of the first, second, fourth, and third blades are deflected from engagement with the surface of the environment.

In example 21, the subject matter of example 20 includes wherein the spacer includes a major diameter at an outer periphery of the spacer, wherein the major diameter of the spacer is less than or equal to a deflection diameter of the first and second elongate members.

Example 22 is a method of operating a mobile cleaning robot, comprising operating a drive wheel of the mobile cleaning robot to navigate the mobile cleaning robot in an environment; and operating a cleaning assembly to ingest debris from the environmental surface, the cleaning assembly comprising, for operating the mobile cleaning robot in a cleaning mode: a roller rotatable relative to the body of the mobile cleaning robot and engageable with the surface to direct debris toward the suction duct, the roller comprising a roller core extending along a longitudinal axis of the roller; a first elongated member circumferentially surrounding a first portion of the roll core; a second elongated member circumferentially surrounding a second portion of the roll core; and a spacer at least partially circumferentially surrounding the roller core between the first and second elongated members, the spacer being engageable with the floor surface and configured to avoid debris from collecting between the first and second elongated members.

In example 23, the subject matter of example 22 includes directing debris on the first elongate member to the second elongate member with the spacer.

In example 24, the subject matter of example 23 includes directing debris on the second elongate member to the first elongate member with the spacer.

In example 25, the subject matter of example 24 includes preventing debris within the first elongate member and within the second elongate member from collecting between the first elongate member and the second elongate member; directing debris wrapped around the first elongate member toward the second elongate member; and directing debris wrapped around the second elongate member toward the first elongate member.

Example 26 is an apparatus comprising means for performing any of examples 1-25.

In example 27, the apparatus or method of any one or any combination of examples 1-25 may optionally be configured such that all elements or options listed are available for use or selection therefrom.

The above detailed description includes references to the accompanying drawings, which form a part of the detailed description. The drawings show, by way of illustration, specific embodiments that may be practiced. These embodiments are also referred to herein as "examples". Such examples may include elements other than those shown or described. However, the inventors also contemplate examples in which only those elements shown or described are provided. Moreover, the inventors contemplate examples using any combination or permutation of those elements shown or described (or one or more aspects thereof), whether with respect to a particular example (or one or more aspects thereof), or with respect to other examples (or one or more aspects thereof) shown or described herein.

All publications, patents, and patent documents mentioned in this document are incorporated by reference in their entirety as if individually incorporated by reference. If there is inconsistent usage between this document and the documents incorporated by reference, the usage in the incorporated reference documents should be considered as a complement to the usage of this document; for non-adjustable inconsistencies, the usage in this document controls.

In this document, the term "a" is used as is common in patent documents to include one or more, independent of any other instance or usage of "at least one" or "one or more". In this document, the term "or" is used to refer to non-exclusive or such that "a or B" includes "a but not B", "B but not a" and "a and B" unless otherwise indicated. In the appended claims, the terms "including" and "in which" are used as the plain-english equivalents of the respective terms "comprising" and "wherein. Furthermore, in the following claims, the terms "comprise" and "include" are open-ended, i.e., a system, device, article, or process in the claims that includes elements other than those listed after such a term is still considered to be within the scope of the claim. Furthermore, in the following claims, the terms "first," "second," and "third," etc. are used merely as labels, and are not intended to impose numerical requirements on their objects.

The above description is intended to be illustrative, and not restrictive. For example, the above-described examples (one or more aspects thereof) may be used in combination with each other. Other embodiments may be used, such as by one of ordinary skill in the art after reviewing the above description. The abstract is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Furthermore, in the above detailed description, various features may be combined together to simplify the present disclosure. This should not be interpreted as intending to make the unclaimed disclosed feature critical to any claim. Rather, the inventive subject matter may lie in less than all features of a particular disclosed embodiment. Thus the following claims are hereby incorporated into this detailed description, with each claim standing on its own as a separate embodiment. The scope of the embodiments should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.

Claims

1. A roller for a mobile cleaning robot, the roller comprising:

A roll core extending along a longitudinal axis of the roll;

A first elongate member engageable with a floor surface, the first elongate member at least partially surrounding a first portion of the roll core;

A second elongated member engageable with the floor surface, the second elongated member at least partially surrounding a second portion of the roll core; and

A spacer at least partially surrounding the roll core and positioned between the first and second elongated members, the spacer engageable with the floor surface and configured to inhibit debris collection between the first and second elongated members.

2. The roller of claim 1, wherein the first elongated member comprises:

a first skeleton;

a first wing extending radially outwardly from the first armature and along at least a portion of the longitudinal axis; and

A second airfoil extending radially outwardly from the first armature and along at least a portion of the longitudinal axis, wherein the first and second airfoils are circumferentially spaced apart from each other to define a first airfoil gap therebetween.

3. The roller of claim 2, wherein the second elongated member further comprises:

a second skeleton;

A third wing extending radially outwardly from the second backbone and along at least a portion of the longitudinal axis; and

A fourth airfoil extending radially outwardly from the second backbone and along at least a portion of the longitudinal axis, wherein the third airfoil and the fourth airfoil are circumferentially spaced apart from each other to define a second airfoil gap therebetween.

4. A roller according to claim 3, wherein the first and second wings extend around the first elongate member in a first helical pattern, wherein the third and fourth wings extend from the spacer in a second helical pattern, and wherein the second helical pattern is symmetrical with the first helical pattern about the spacer.

5. The roller of claim 4, wherein the spacer comprises:

A base connected to and extending circumferentially around the roll core and extending radially outwardly therefrom; and

A body connected to the base, extending circumferentially around the base, and extending radially outward from the base.

6. The roller of claim 5, wherein the body of the spacer further comprises:

A first fin extending axially from a first surface of the body, the first fin also extending axially from a second surface of the body such that the first fin extends at least partially into the first fin gap from the first surface and the second surface; and

A second fin circumferentially spaced from the first fin and extending axially from the first surface, the second fin also extending axially from the second surface such that the second fin extends at least partially into the second fin gap from the first surface and the second surface.

7. The roller of claim 6, wherein the first and second wings of the first elongate member and the third and fourth wings of the second elongate member compress radially inward under conditions in which the first elongate member or the second elongate member contacts a floor, the first, second, third and fourth wings together defining a deflection diameter at a maximum deflection position when any of the first, second, third and fourth wings deflects from engagement with a floor surface.

8. The roller of claim 7, wherein the spacer comprises a major diameter such that the spacer is within the major diameter, and wherein the major diameter of the spacer is less than or equal to the deflection diameter.

9. The roller of any of claims 5-8, wherein the spacer comprises a first portion and a second portion, wherein the first portion and the second portion are detachably coupled to one another.

10. The roller of any one of claims 5-8, wherein the body of the spacer comprises a plurality of bristles extending radially outward from the body of the spacer.