Rolling brush motor and floor brush assembly

Abstract

The application provides a rolling brush motor and a ground brush assembly. The rolling brush motor comprises a stator, a rotor shell and a fixed shaft led out from the stator and the rotor shell; the stator is fixed on the fixed shaft; the rotor shell is rotatably sleeved on the stator and is configured to drive the rolling brush of the cleaning device to rotate; a wire channel is arranged in the first end of the fixed shaft to lead the lead wire of the stator out of the rotor shell; and the material of the fixed shaft is engineering plastic. The fixed shaft is made of engineering plastic to form the wire channel in the fixed shaft, realize internal wiring, enhance waterproof reliability, reduce the entry of water vapor into the rotor shell from the assembly position of the bearing and the fixed shaft, stably assemble the uniform outer surface of the fixed shaft and the inner ring of the bearing to reduce shaking, and avoid the need for more installation fixing structures and space for additional wiring.

Description

Technical Field

[0001] This application relates to the field of cleaning equipment technology, specifically to a roller brush motor and a floor brush assembly. Background Technology

[0002] In the field of drive motor technology for cleaning equipment, such as the roller brush motor of a floor scrubber, which is used to drive the roller brush to rotate, in order to cope with the humid environment and dusty conditions of wet cleaning during cleaning operations, it is generally expected that the motor can have excellent waterproof and dustproof performance while realizing power transmission, so as to ensure the long-term operational reliability of the cleaning equipment.

[0003] In related technologies, brushed motors are typically brushed motors, which rely on carbon brushes for commutation. However, brushed motors suffer from drawbacks such as frequent maintenance due to carbon brush wear, high noise levels caused by commutation sparks and frictional vibrations, and poor water resistance. To address these issues, some brushed motors in related technologies are gradually replacing traditional brushed motors with brushless direct-drive motors. Brushless direct-drive motors include external rotor motors (i.e., internal stator motors). In external rotor motors, the rotor is on the outside and the stator is on the inside. Generally, the stator coil leads are directly led out through holes or interfaces in the end cover, or embedded in grooves on the outer surface of the metal central shaft. If the wires are led out directly from the end cover, the sealing treatment at the holes or interfaces is complex, and reliability is easily affected by assembly and vibration. If the wires are routed through grooves on the outer surface of the metal central shaft, the wire channels are exposed to the outside of the shaft. In humid environments, moisture can easily penetrate into the motor through the grooves. Both of these factors can cause the internal wires and coil insulation to fail due to moisture, leading to a short circuit risk. Furthermore, external grooving on the metal central shaft will damage the integrity and uniformity of the mating surface between the central shaft and the bearing, which may lead to loosening of the fit and radial wobble under high-frequency vibration, thus affecting the transmission accuracy.

[0004] Therefore, in applications involving high humidity and vibration, such as floor scrubbers, how to route the motor leads to avoid exposing the lead channels to a humid environment, thereby improving the motor's sealing, waterproofing, and reliability, has become a specific technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] In view of this, the embodiments of this application aim to provide a roller brush motor and a floor brush assembly to solve the problem of improving the sealing and waterproof performance and reliability of the roller brush motor in the prior art.

[0006] This application provides a roller brush motor, including a stator, a rotor housing, and a fixed shaft extending from the stator and the rotor housing; the stator is fixedly mounted on the fixed shaft; the rotor housing is rotatably fitted over the stator and is configured to drive the roller brush of a cleaning device to rotate; a wire channel is provided in the first end of the fixed shaft for guiding the leads of the stator to the outside of the rotor housing; wherein the fixed shaft is made of engineering plastic.

[0007] By using engineering plastics to manufacture the fixed shaft, wire channels can be opened inside the fixed shaft to realize internal wiring function, enhance waterproof reliability, and the internal opening wiring method has better sealing, dustproof and waterproof performance than the external slot wiring of the metal central shaft. This wiring method also avoids the need for additional wiring and more installation and fixing structures and space, which is conducive to achieving a compact structural design. In addition, the fixed shaft made of engineering plastic has good insulation properties, which helps to eliminate the risk of leakage and improve the safety and reliability of the roller brush motor. Furthermore, the external rotor roller brush motor in this embodiment is generally a brushless motor design, which eliminates carbon brush wear and commutation sparks of brushed motors, making the roller brush motor without vulnerable parts.

[0008] In one embodiment, the wire channel includes a first hole and a second hole that communicate with each other, the first hole extending radially from the outer surface of the fixed shaft along the fixed shaft, and the second hole extending axially from the end face of the first end along the fixed shaft.

[0009] In one embodiment, after the roller brush motor is assembled to the cleaning device, the axis of the first hole and the axis of the second hole are both located on a vertical plane passing through the axis of the rotor housing.

[0010] In one embodiment, the axis of the first hole is parallel to the vertical plane and perpendicular to the axis of the fixed shaft, and the axis of the second hole coincides with the axis of the fixed shaft.

[0011] In one embodiment, the fixed shaft passes through the stator and the rotor housing. The second end of the fixed shaft is positioned opposite the first end, and a middle section of the fixed shaft connects the first and second ends. The radius of the second end is smaller than the radius of the middle section. The first end cover of the rotor housing is connected to the second end via a first bearing, and the second end cover of the rotor housing is connected to the first end via a second bearing. The stator is fitted onto the middle section, the first bearing is fitted onto the second end, and the second bearing is fitted onto the second end. Here, the first and second ends of the fixed shaft refer to portions of the fixed shaft's end, which are approximately cylindrical in shape. The first end, being fixedly connected, can undergo partial spline deformation.

[0012] In one embodiment, a first limiting portion is provided around the outer peripheral surface of the first end, and the two opposite ends of the second bearing along the axial direction of the fixed shaft respectively abut against the first limiting portion and the second end cover to restrict the movement of the second bearing along the axial direction of the fixed shaft.

[0013] In one embodiment, the outer peripheral surface of the first end is further surrounded by a second limiting portion, the first limiting portion and the second limiting portion are spaced apart along the axial direction of the fixed shaft, and the first hole is located between the first limiting portion and the second limiting portion; one end of the stator along the axial direction of the fixed shaft abuts against the side of the second limiting portion away from the first limiting portion, so as to position the stator along the axial direction of the fixed shaft.

[0014] In one embodiment, the second end cover has a third limiting portion extending axially along the fixed shaft on the side facing the stator. The third limiting portion is disposed around the second bearing to restrict the radial movement of the bearing along the fixed shaft. The inner diameter of the third limiting portion gradually increases axially along the fixed shaft from the end near the second end cover to the end near the stator.

[0015] In one embodiment, three first holes are evenly spaced around the first end in a circumferential manner; the stator is provided with a three-phase winding, and the three-phase winding respectively leads out a U-phase lead, a V-phase lead, and a W-phase lead. The U-phase lead, the V-phase lead, and the W-phase lead are respectively inserted into the corresponding first holes and all extend out of the first end from the second holes; or the stator is provided with a position detection unit, and the position detection unit leads out a positive power line, a negative power line, and a signal line. The positive power line, the negative power line, and the signal line are respectively inserted into the corresponding first holes and all extend out of the first end from the second holes.

[0016] In one embodiment, the roller brush motor further includes a transmission structure located at the second end of the fixed shaft. The transmission structure is fixedly connected to the rotor housing and detachably fixedly connected to the roller brush. The transmission structure is fixedly connected to the first end cover of the rotor housing, and the first end cover is connected to the fixed shaft through a first bearing.

[0017] In one embodiment, the roller brush motor further includes a connecting structure disposed at the first end and located outside the rotor housing. The connecting structure includes a first connector and a second connector. One end of the first connector is fixedly disposed at the first end, and the other end is connected to the motor mounting bracket of the cleaning device. The second connector is rotatably sleeved on the first connector via a third bearing. The roller brush is sleeved on the outer peripheral surface of the second connector and seals against the second connector. When the roller brush is assembled on the roller brush motor, along the axis of the fixed shaft, the ends of the roller brush, the first connector, and the second connector near the motor mounting bracket are approximately flush. The transmission structure of the roller brush motor can drive the roller brush to rotate, and the roller brush, through frictional force, drives the second connector to rotate relative to the first connector / fixed shaft.

[0018] In one embodiment, the first connector includes a first connecting segment and a second connecting segment that are fixedly connected; the first connecting segment is fixedly connected to the first end and is located between the rotor housing and the second connecting segment; the second connecting segment is connected to the second connector through the third bearing and is connected to the motor mounting bracket; wherein the outer diameter of the first connecting segment is larger than the outer diameter of the second connecting segment.

[0019] In one embodiment, a sealing structure is provided between the second connector and the roller brush to seal the radial gap between the second connector and the roller brush.

[0020] In one embodiment, the wire channel forms an L-shaped channel, and the fixed shaft is an injection-molded integral structure.

[0021] In another aspect, this application provides a floor brush assembly for a cleaning device, including a floor brush housing, a roller brush, and a roller brush motor as described in the above embodiments. The roller brush is sleeved on the roller brush motor, the roller brush motor is connected to the floor brush housing, and the roller brush motor is used to drive the roller brush to rotate. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the assembly of the roller brush motor in one embodiment of this application.

[0023] Figure 2 This is a cross-sectional schematic diagram of a roller brush motor in one embodiment of this application.

[0024] Figure 3 For this application Figure 2 A magnified view of a portion of point A in the middle.

[0025] Figure 4 This is a schematic diagram of the fixed shaft in one embodiment of this application.

[0026] Figure 5This is a schematic diagram of the assembly of the roller brush motor part structure in one embodiment of this application.

[0027] Figure 6 This is a schematic diagram of the structure of the first connector in one embodiment of this application.

[0028] Figure label: 100. Roller brush motor; 101. Stator; 102. Rotor housing; 103. Fixed shaft; 104. First end; 105. Wire channel; 106. First hole; 107. Second hole; 108. Transmission structure; 109. Second end; 110. First end cover; 111. First bearing; 112. First transmission component; 113. Second transmission component; 114. Transmission part; 115. Buffer component; 116. Connecting structure; 117. First connecting component; 11 8. Second connecting piece; 119. Motor mounting bracket; 120. Third bearing; 121. Spline; 123. First connecting section; 124. Second connecting section; 125. Sealing structure; 126. Iron core; 127. Coil; 128. Second end cover; 129. Second bearing; 130. Magnet; 131. Intermediate section; 132. Buffer structure; 133. Mounting groove; 134. First limiting part; 135. Second limiting part; 136. Third limiting part. Detailed Implementation

[0029] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0030] It should be noted that in the description of this application, the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used solely for the convenience of describing this application and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the specification of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0032] In the field of drive motor technology for cleaning equipment, such as the roller brush motor used to drive the roller brush of a floor scrubber, in order to cope with the humid environment and dusty conditions of wet cleaning during cleaning operations, it is generally expected that the roller brush motor can have excellent waterproof and dustproof performance while realizing power transmission, so as to ensure the long-term operational reliability of the cleaning equipment.

[0033] In related technologies, brushless direct-drive motors have been gradually replaced by brushed motors to improve lifespan and reliability. Among them, external rotor motors have attracted attention due to their compact structure and high torque density. In external rotor motors, the stator coil leads usually pass directly through the reserved holes or interfaces in the motor end cover, or grooves are machined on the outer surface of the central fixed shaft made of metal, and the leads are buried in the grooves before being led out from the end.

[0034] However, when the above solutions are applied to the high-moisture, high-vibration conditions faced by floor scrubbers, the sealing reliability of the lead wire exit method is not ideal. This is because the above solutions, in order to achieve physical connection of the lead wire from the inside to the outside, inevitably compromise the sealing integrity of the motor structure and the stability of the mechanical support through the wire path. If the wire is led directly out from the end cover opening, a wire hole needs to be made in the end cover. The sealing structure at this point is prone to failure under high-frequency vibration due to stress concentration or assembly tolerances, becoming a weak point for moisture intrusion. If the wiring is slotted on the outer surface of the metal central shaft, exposing the wire channel to the outside of the shaft, moisture in a humid environment can easily penetrate into the motor through the slots. Simultaneously, external slotting on the central shaft, a critical support component, locally weakens its structural strength and disrupts the geometric integrity and uniformity of its mating surface with the bearing. Under high-load vibration, this may lead to loosening of the fit or abnormal wear, affecting transmission accuracy and support rigidity.

[0035] Researchers discovered through in-depth analysis that the cause of the above problems is that both the end cap openings and the grooves on the outer surface of the central shaft create potential leakage paths, making the motor's sealing performance highly dependent on the performance and assembly quality of the additional seals. However, this reliability may not be ideal under the complex working conditions of cleaning equipment.

[0036] To address the aforementioned problems, this application proposes a different technical solution. Its core lies in employing a fixed shaft made of non-metallic material, extending from the stator and rotor housings, and constructing a wire channel within the internal space of this fixed shaft to provide support and guide the wires internally. This improvement allows the wires to pass through the fixed shaft with protection, completely avoiding the need for additional wire holes in the end caps or slots on the outer surface of the fixed shaft. This effectively prevents moisture from entering the motor along the wire path without sacrificing the motor's basic electromagnetic performance and structural support function, and eliminates damage to the structural integrity of the fixed shaft caused by exposed wiring slots. In other words, a fixed shaft with a built-in wire channel is provided to solve the problems of poor sealing reliability and potential mechanical failures caused by the wire extension method in brushless direct-drive motors operating in humid and high-vibration environments, achieving long-term stable operation of the motor under humid conditions.

[0037] See Figures 1 to 4 One embodiment of this application provides a roller brush motor 100, including a stator 101, a rotor housing 102, and a fixed shaft 103 extending from the stator 101 and the rotor housing 102; the stator 101 is fixedly mounted on the fixed shaft 103; the rotor housing 102 is rotatably sleeved on the stator 101 and is configured to drive a roller brush (not shown) of a cleaning device (not shown) to rotate; a wire channel 105 is provided in the first end 104 of the fixed shaft 103 for guiding the leads of the stator 101 to the outside of the rotor housing 102; wherein, the fixed shaft 103 is made of engineering plastic.

[0038] This embodiment provides a basic configuration of a roller brush motor 100, designed to replace the brushed motor in a traditional floor scrubber with a brushless direct-drive motor. This roller brush motor 100 is an improvement on the external rotor motor (i.e., the internal stator 101 motor). The core support and wiring component of the roller brush motor 100 is a complete, slender fixed shaft 103. The fixed shaft 103 is made of engineering plastic, such as a composite material with polyamide as the matrix and glass fiber reinforcement (e.g., PA6+45%GF composite material, i.e., a composite material of polyamide 6 (PA6) and 45% glass fiber (GF)), integrally molded by injection molding. This fixed shaft 103, made of this engineering plastic material, replaces the metal central shaft commonly used in traditional external rotor motors, possessing good rigidity, fatigue resistance, and wear resistance, and can withstand the continuous vibration of the floor brush. Compared to a metal central shaft, the fixed shaft 103 made of engineering plastic is lighter, which helps to reduce the operating load and makes it easier to set up a guide channel inside the fixed shaft 103. At the same time, the inherent good insulation of engineering plastic eliminates the risk of leakage of the shaft itself, and its anti-corrosion properties are suitable for high moisture conditions.

[0039] The fixed shaft 103 is fixedly connected to the internal stator 101, and connected to the externally rotating rotor housing 102 via bearings (see first bearing 111 and second bearing 129 below), providing a stable, coaxial radial support reference for the rotor housing 102. This overall force-bearing layout facilitates maintaining the consistency of the front-to-back axial direction of the roller brush motor 100 within a compact space, simplifying the overall structure. The stator 101 is fixedly mounted on the outer periphery of the middle section of the fixed shaft 103, and can adopt, for example, a 14-pole, 12-slot brushless motor structure design. This pole-slot combination effectively reduces cogging torque, adapting to the low-speed, high-load operating conditions of floor scrubber brushes, and reducing vibration and operating noise from the electromagnetic source.

[0040] Unlike metal central shafts that typically only allow external slotting for wiring, engineering plastics, due to their excellent moldability, allow for protected wiring channels to be created inside the shaft. In this embodiment, a wire channel 105 is machined or formed inside the first end 104 of the fixed shaft 103. The leads from the stator 101 coil 127 are safely guided to the outside of the rotor housing 102 via this internal wire channel 105, fundamentally preventing interference or wear between the leads and internal rotating components (such as the second end cover 128 below) and the front-end output connection structure 116. This integrated design requires no additional wiring space, adapts to the compact installation requirements of the roller brush motor 100, and the sealing, dustproof, and waterproof performance of the internally perforated wire channel 105 is superior to that of external slotting.

[0041] By using engineering plastics to manufacture the fixed shaft 103, wire channels 105 can be opened inside the fixed shaft 103 to realize internal wiring function, enhance waterproof reliability. Compared with external slotted wiring, internal opening wiring can also reduce moisture from entering the rotor housing 102 from the assembly point of the bearing (see the second bearing 129 below) and the fixed shaft 103. Moreover, the uniform outer surface of the fixed shaft 103 (without slotted wiring on the outer surface of the fixed shaft 103) can be stably assembled with the inner ring of the bearing, reducing shaking. This wiring method also avoids the need for additional wiring to install more fixing structures and space, which is conducive to achieving a compact structural design. In addition, the fixed shaft 103 made of engineering plastic has good insulation properties, which helps to eliminate the risk of leakage and improve the safety and reliability of the roller brush motor 100. Furthermore, the roller brush motor 100 in this embodiment is a brushless design, which eliminates carbon brush wear and commutation sparks of brushed motors, making the roller brush motor 100 have no vulnerable parts.

[0042] See Figure 2 , Figure 4 , Figure 5In one embodiment, the stator 101 includes an iron core 126 and a coil 127 wound on the iron core 126. A mounting groove 133 is provided on the fixed shaft 103 for fixing the iron core 126 to the fixed shaft 103. A magnet 130 is provided on the inner wall of the rotor housing 102 to drive the rotor housing 102 to rotate after the coil 127 is energized.

[0043] See Figures 2 to 4 In one embodiment, the wire channel 105 includes a first hole 106 and a second hole 107 that are interconnected. The first hole 106 extends radially from the outer surface of the fixed shaft 103 along the fixed shaft 103, and the second hole 107 extends axially from the end face of the first end 104 along the fixed shaft 103.

[0044] At the first end 104 of the fixed shaft 103 made of engineering plastic, a wire channel 105 consisting of two hole segments is formed by injection molding or subsequent processing. This split-channel structure fully utilizes the advantage of engineering plastics in easily molding complex internal features. Specifically, the first hole 106 extends a certain depth from the outer cylindrical surface of the region of the first end 104 of the fixed shaft 103 along the radial direction of the fixed shaft 103, and the second hole 107 extends inward from the end face of the first end 104 of the fixed shaft 103 along the axial direction of the fixed shaft 103. The first hole 106 and the second hole 107 intersect and communicate inside the fixed shaft 103 to form the wire channel 105. The diameters of the first hole 106 and the second hole 107 are usually set to be equal, and their radii can be, but are not limited to, between 3 mm and 5 mm, to balance the ease of wire insertion with the impact on the structural strength of the shaft. During the wire threading assembly, the lead wire of the stator 101 coil 127 first enters the fixed shaft 103 through the first hole 106 extending radially from the fixed shaft 103, then turns at the channel intersection and enters the second hole 107, and finally exits from the second hole 107 extending axially from the fixed shaft 103.

[0045] By designing the guide channels as interconnected first holes 106 (i.e., radial holes) and second holes 107 (i.e., axial holes), without reserving wiring space outside the brush motor 100, it is beneficial to achieve compact design and improve space utilization. Furthermore, the two holes can be completed by radial and axial drilling processes respectively, improving the feasibility of processing. In addition, this wiring path forms a natural lead wire turning path, so that the lead wires enter from the radial holes on the side of the stator 101 and then turn to exit from the axial holes. The path is clear and smooth, and this wiring path also facilitates sealing treatment. The regular channel structure provides uniform filling space for subsequent injection of sealant, which is conducive to forming a reliable sealing insulator.

[0046] See Figure 3In one embodiment, after the roller brush motor 100 is assembled to the cleaning device, the axis of the first hole 106 and the axis of the second hole 107 are both located on a vertical plane passing through the axis of the rotor housing 102.

[0047] When the roller brush motor 100 is installed on the floor scrubber's brush in its working posture, the axis of the rotor housing 102 is horizontal. At this time, a vertical plane is defined passing through the axis of the rotor housing 102, perpendicular to the ground plane and encompassing the axis of the rotor housing 102. In this embodiment, the central axis of the first hole 106 and the central axis of the second hole 107 are both located within this same vertical plane to avoid a significant reduction in the strength of the fixed shaft 103 due to the guide channel being too close to the outer periphery of the fixed shaft 103, thereby affecting the stability of the fixed shaft 103.

[0048] See Figure 3 Furthermore, in one embodiment, the axis of the first hole 106 is parallel to the vertical plane and perpendicular to the axis of the fixed shaft 103, and the axis of the second hole 107 coincides with the axis of the fixed shaft 103.

[0049] Within this vertical plane, the axis of the first hole 106 is defined as parallel to the vertical plane and perpendicular to the axis of the fixed shaft 103, meaning the first hole 106 is vertically upward with its entrance facing upward. Simultaneously, the axis of the second hole 107 coincides with the axis of the fixed shaft 103. Both the axis of the fixed shaft 103 and the axis of the second hole 107 lie within this vertical plane; that is, the second hole 107 is a central hole concentric with the fixed shaft 103, and the second hole 107 is formed by a central opening at the end of the fixed shaft 103.

[0050] By designing the axes of the first hole 106 and the second hole 107 to be located in the same vertical plane, and the second hole 107 being coaxial with the fixed shaft 103, the processing and manufacturing of the fixed shaft 103 is facilitated (such as injection molding or drilling), and it is beneficial to ensure the positional accuracy of the hole and the coaxiality of the shaft itself, thereby improving the structural stability of the fixed shaft 103. The lead wire is led out from the end center hole (i.e., the second hole 107) of the fixed shaft 103 through the first hole 106 located in the vertical plane. The wiring path is centered and symmetrical, which is beneficial to optimize the stress distribution of the fixed shaft 103, improve the mass distribution of the lead wire inside the fixed shaft 103, and structurally enhance the stability of the fixed shaft 103, thereby improving the overall smoothness and reliability of the roller brush motor 100 under the high vibration conditions of the floor scrubber.

[0051] See Figure 2 and Figure 4In one embodiment, the fixed shaft 103 passes through the stator 101 and the rotor housing 102. The second end 109 of the fixed shaft 103 is disposed opposite to the first end 104. The middle section 131 of the fixed shaft 103 is connected between the first end 104 and the second end 109. The radius of the second end 109 is smaller than the radius of the middle section 131. The first end cover 110 of the rotor housing 102 is connected to the second end 109 through a first bearing 111. The second end cover 128 of the rotor housing 102 is connected to the first end 104 through a second bearing 129. The stator 101 is sleeved on the middle section 131. The first bearing 111 is sleeved on the second end 109. The second bearing 129 is sleeved on the second end 109.

[0052] In this embodiment, the fixed shaft 103 extends axially through the entire internal space of the roller brush motor 100, with its two ends extending to the outside of the rotor housing 102. The fixed shaft 103 is mostly solid, and is designed as a columnar structure with different radii along its axial direction. This allows for the connection of different components to the columns, facilitating the machining of the fixed shaft 103 and the assembly / disassembly of components. Furthermore, this stepped shaft design with varying radii reduces the overall weight of the fixed shaft 103 while maintaining its strength.

[0053] In this embodiment, since the fixed shaft 103 is designed as an integral through shaft that penetrates the rotor housing 102, this integral through design is beneficial to the processing and manufacturing of the fixed shaft 103 and facilitates the assembly and disassembly of the components it is assembled with. Compared with a multi-segment central shaft, the fixed shaft 103 in this embodiment has high strength.

[0054] The rotor housing 102 is supported on the second end 109 and the first end 104 of the fixed shaft 103 by the first bearing 111 and the second bearing 129 arranged at intervals, and the stator 101 is supported by the thicker middle section 131, thereby ensuring that the center line of the rotor housing 102 coincides with the center line of the stator 101, so as to ensure the stability and accuracy of the fixed shaft 103 and reduce the output wobbling of the roller brush motor 100.

[0055] See Figure 3 and Figure 4 In one embodiment, a first limiting portion 134 is provided around the outer peripheral surface of the first end 104, and the opposite ends of the second bearing 129 along the axial direction of the fixed shaft 103 respectively abut against the first limiting portion 134 and the second end cover 128 to restrict the movement of the second bearing 129 along the axial direction of the fixed shaft 103.

[0056] The first limiting part 134 is an annular boss surrounding the outer circumferential surface of the first end 104 of the fixed shaft 103. The first limiting part 134 is an annular boss directly formed on the fixed shaft 103 made of engineering plastic material. After the inner ring of the second bearing 129 is installed on the journal of the first end 104, one axial end face of the second bearing 129 (i.e., the inner ring end face of the second bearing 129) abuts tightly against the side of the first limiting part 134. When the second end cover 128 is assembled in place, the other axial end face of the second bearing 129 (i.e., the outer ring end face of the second bearing 129) abuts tightly against the side of the second end cover 128, thereby achieving axial positioning of the second bearing 129.

[0057] By setting the first limiting part 134, the axial position of the second bearing 129 is positioned and limited during the installation of the second bearing 129, so as to provide accurate and reliable axial positioning. The mechanical abutment positioning method is more stable than simply relying on interference fit, which can effectively resist axial force and prevent relative sliding between the bearing inner ring and the journal, thereby avoiding wear and loss of precision. At the same time, when the second end cover 128 is installed in place, the end face of the second end cover 128 further limits the second bearing 129, so that the second bearing 129 is clamped between the first limiting part 134 and the second end cover 128, thereby restricting the movement of the second bearing 129 along the fixed shaft 103. This ensures that when the roller brush motor 100 is assembled with the floor scrubber brush for cleaning, the second bearing 129 cannot move along the fixed shaft 103, thereby helping to improve the stability of the roller brush motor 100.

[0058] See Figure 3 and Figure 4 In one embodiment, the outer peripheral surface of the first end 104 is further surrounded by a second limiting portion 135. The first limiting portion 134 and the second limiting portion 135 are spaced apart along the axial direction of the fixed shaft 103. The first hole 106 is located between the first limiting portion 134 and the second limiting portion 135. One end of the stator 101 along the axial direction of the fixed shaft 103 abuts against the side of the second limiting portion 135 away from the first limiting portion 134 to position the stator 101 along the axial direction of the fixed shaft 103.

[0059] It should be noted that, in combination Figure 4 The bold dashed lines shown in this application define the first end 104 of the fixed shaft 103 as the end face of the second limiting portion 135 facing the middle section 131, which includes the first limiting portion 134 and the second limiting portion 135 along the axial direction; and the second end 109 of the fixed shaft 103 as the end face of the middle section 131 away from the second limiting portion 135 along the axial direction, which is the other end of the fixed shaft 103 away from the first end 104.

[0060] At the first end 104 of the fixed shaft 103, in addition to the first limiting part 134, another annular boss, namely the second limiting part 135, is formed closer to the middle section 131. The first limiting part 134 and the second limiting part 135 are spaced apart along the axial direction of the fixed shaft 103, forming an annular groove area. The entrance of the first hole 106 is located on the outer surface of this groove area, which makes the entrance of the first hole 106 inside the rotor housing 102, making it difficult for moisture to enter the rotor housing 102, thereby improving the sealing and waterproof performance of the brush motor 100. When the iron core 126 of the stator 101 is assembled onto the middle section 131, its end face facing the first end 104 will closely abut against the side of the second limiting part 135. The second limiting part 135 thus acts as a mechanical stop for the stator 101 in the axial direction to position the stator 101 along the axial direction of the fixed shaft 103.

[0061] By setting the second limiting part 135, accurate axial mechanical positioning is provided for the stator 101 to ensure the positional accuracy of the stator 101 in the axial direction; and by setting the inlet of the wire channel 105 between the first limiting part 134 and the second limiting part 135, it is more difficult for water vapor to enter the inlet of the first hole 106 along the outer surface of the fixed shaft 103, thereby further improving the sealing and waterproof performance of the roller brush motor 100 and thus improving the reliability of the roller brush motor 100.

[0062] See Figure 3 In one embodiment, the second end cap 128 is provided with a third limiting portion 136 extending axially along the fixed shaft 103 on the side facing the stator 101. The third limiting portion 136 is disposed around the second bearing 129 and is used to limit the radial movement of the bearing along the fixed shaft 103. The inner diameter of the third limiting portion 136 gradually increases axially along the fixed shaft 103 from the end near the second end cap 128 to the end near the stator 101.

[0063] On the second end cover 128 of the rotor housing 102, a cylindrical third limiting portion 136 extends integrally from the side of the second end cover 128 facing the stator 101. The inner hole of the third limiting portion 136 surrounds the outer side of the outer ring of the second bearing 129. The smaller part of the inner hole of the third limiting portion 136 abuts tightly against the outer ring of the second bearing 129 to limit the radial movement of the second bearing 129. The inner hole of the third limiting portion 136 is designed in a trumpet shape for assembly.

[0064] By setting the third limiting part 136 to restrict the radial movement of the second bearing 129, an additional radial contact surface is provided for the outer ring of the second bearing 129, enhancing the radial support rigidity and helping to reduce the vibration when the rotor housing 102 rotates. By designing the third limiting part 136 as a horn shape, the inner hole wall of the third limiting part 136 forms a guide surface, so as to quickly and accurately assemble the second end cover 128, avoiding damage to the bearing due to forced installation, and improving assembly efficiency and yield.

[0065] See Figures 2 to 4 In one embodiment, three holes 106 are evenly spaced around the first end 104 in the circumferential direction; the stator 101 is provided with a three-phase winding (not shown), and the three-phase winding respectively leads out a U-phase lead, a V-phase lead and a W-phase lead. The U-phase lead, the V-phase lead and the W-phase lead are respectively inserted into the corresponding first holes 106, and all extend out of the first end 104 from the second hole 107.

[0066] In another embodiment, three holes 106 are evenly spaced around the first end 104 in the circumferential direction; the stator 101 is provided with a position detection unit (not shown, such as a Hall sensor, to detect the real-time rotational position of the rotor housing 102), the position detection unit has a positive power line, a negative power line and a signal line leading out, the positive power line, the negative power line and the signal line respectively pass through the corresponding first hole 106, and all extend out of the first end 104 from the second hole 107.

[0067] Three first holes 106 are evenly distributed along the circumference of the first end 104 of the fixed shaft 103, with the three first holes 106 spaced 120° apart. The above two embodiments provide wiring schemes for the conductor channel 105 in two application scenarios. In the first application scenario, for a three-phase brushless DC motor, the three power lines (U-phase, V-phase, and W-phase) drawn from the stator 101 coil 127 are independently inserted into the three corresponding radial first holes 106, converge within the fixed shaft 103, and then converge and exit from a single second hole 107. In the second application scenario, if the stator 101 is equipped with a position detection unit, its positive power line, negative power line, and signal line can also be inserted into the three first holes 106 respectively and converge and exit from the same second hole 107.

[0068] By evenly distributing three first holes 106 around the first end 104, the fixed shaft 103 is subjected to uniform force and can meet the requirements of the three-phase power line of the brushless motor. Multiple lead cables are inserted through separate holes, avoiding the tangling and friction of multiple wires in a single channel, reducing the risk of short circuits and improving the reliability and safety of wiring. At the same time, multiple lead cables are led out through the same outlet so that they can be uniformly connected to the outside of the roller brush motor 100 using a single connector, simplifying the assembly and maintenance process.

[0069] See Figure 1 , Figure 2 , Figure 5 In one embodiment, the roller brush motor 100 further includes a transmission structure 108 located at the second end 109 of the fixed shaft 103. The transmission structure 108 is fixedly connected to the rotor housing 102 and detachably fixedly connected to the roller brush.

[0070] To transmit the rotational power of the rotor housing 102 to the roller brush, this embodiment adds a transmission structure 108 to the outer side of the second end 109 of the fixed shaft 103. This transmission structure 108 is directly or indirectly rigidly connected to the rotor housing 102 to drive the roller brush to rotate. The output interface of the transmission structure 108 is designed to form a detachable fixed connection with the roller brush of the cleaning equipment, for example, by using a flange with screw locking, a quick-release buckle mechanism, or a spline 121 connection. In this embodiment, a spline 121 connection is used to achieve efficient and stable transmission, helping to prevent slippage under high vibration conditions.

[0071] By setting up a transmission structure 108, the rotational power of the rotor housing 102 is transmitted to the roller brush, thereby driving the roller brush to rotate. Moreover, setting up a separate transmission structure 108 also allows the force transmission interface to be externalized, thus protecting the core components of the roller brush motor 100. At the same time, the transmission structure 108 can be customized for different models of roller brushes, while the motor body remains universal, thereby improving the versatility and adaptability of the roller brush motor 100. By setting the transmission structure 108 and the roller brush to be detachably connected, the convenience of maintenance is improved, and the roller brush can be quickly disassembled and replaced.

[0072] See Figure 1 , Figure 2 , Figure 5 Furthermore, the transmission structure 108 is fixedly connected to the first end cover 110 of the rotor housing 102, and the first end cover 110 is connected to the fixed shaft 103 through the first bearing 111.

[0073] The first end cover 110 of the rotor housing 102 is supported on the second end 109 of the fixed shaft 103 by the first bearing 111. The transmission structure 108 is directly fixed to the outer end face of the first end cover 110 by means of screw connection or interference fit, so that when the rotor housing 102 drives the first end cover 110 to rotate, the torque is directly transmitted to the transmission structure 108 fixed thereto, thereby driving the roller brush to rotate.

[0074] By directly fixing the transmission structure 108 to the first end cover 110 and adopting an end-face connection method, the additional transition connectors are eliminated, and the additional axial dimension is hardly increased, resulting in a compact structure. Furthermore, the power transmission chain is short, which leads to high transmission efficiency and good connection rigidity.

[0075] See Figure 1 , Figure 2 , Figure 5 In one embodiment, the transmission structure 108 includes a first transmission member 112 and a second transmission member 113 that are fixedly connected. The first transmission member 112 is fixedly connected to the rotor housing 102, and the second transmission member 113 is detachably fixedly connected to the roller brush. At least one transmission part 114 is evenly distributed on the outer circumferential surface of the second transmission member 113 along the circumferential direction, and the transmission part 114 is engaged with the roller brush.

[0076] In this embodiment, the first transmission component 112 serves as a standard interface component and is fixedly connected to the first end cover 110 of the rotor housing 102. The second transmission component 113 serves as a roller brush adapter and is fixed to the first transmission component 112. At least one protruding transmission portion 114 is evenly distributed along the circumferential direction on the outer peripheral surface of the second transmission component 113. Correspondingly, the roller brush has an interface (not shown) that matches the transmission portion 114. During assembly, the interface of the roller brush is connected to the transmission portion 114 to achieve torque transmission. In a preferred embodiment, four transmission portions 114 are evenly spaced.

[0077] See Figure 1 , Figure 2 , Figure 5 Furthermore, a buffer 115 is fitted onto the transmission part 114. The buffer 115 can be a silicone buffer pad, a rubber spring, or a metal damping pad. In this embodiment, a silicone buffer pad with a thickness between 3-5mm is used as the buffer pad to reduce assembly wear and noise, help reduce impact vibration, and compensate for processing / assembly errors.

[0078] By designing a split transmission structure 108, the first transmission component 112 can be standardized, and the second transmission component 113 can be customized for different roller brush interfaces without modifying the motor body, thereby improving the adaptability and versatility of the transmission structure 108; by evenly distributing at least one transmission part 114 to be firmly connected with the roller brush, a stable and reliable torque transmission can be achieved.

[0079] See Figure 1 , Figure 2 , Figure 6 In one embodiment, the roller brush motor 100 further includes a connection structure 116 disposed at the first end 104 and located outside the rotor housing 102. The connection structure 116 includes a first connector 117 and a second connector 118. One end of the first connector 117 is fixedly disposed at the first end 104, and the other end is connected to the motor mounting bracket 119 of the cleaning device. The second connector 118 is rotatably sleeved on the first connector 117 through a third bearing 120. The roller brush is sleeved on the outer peripheral surface of the second connector 118 and is in sealing contact with the second connector 118.

[0080] The connection structure 116 in this embodiment includes a static first connector 117 and a dynamic second connector 118. One end of the first connector 117 is fixed to the first end 104 of the fixed shaft 103, and the other end is used to connect to the motor mounting bracket 119 of the cleaning equipment. The second connector 118 is rotatably fitted around the first connector 117 via a third bearing 120, and the first connector 117 and the inner ring of the third bearing 120 are fixedly connected via a spline 121. The other end of the roller brush away from the transmission structure 108 is fitted onto the outer peripheral surface of the second connector 118 and is fixedly connected to the second connector 118 via a spline 121.

[0081] In one optimized embodiment, the second connector 118 is a fluororubber shaft lip used to form a radial seal on the third bearing 120.

[0082] By setting up the connection structure 116, which together with the transmission structure 108 supports the roller brush, the stability of the roller brush operation is improved, and the rigidity of the roller brush rotation is also increased. At the same time, the connection structure 116 can also transfer part of the weight and reaction force of the roller brush to the motor mounting bracket 119, improving the stress situation of the roller brush motor 100. Furthermore, the installation and sealing functions are integrated, and the fixed installation structure of the roller brush motor 100 and the rotation support sealing structure 125 of the roller brush are integrated into a single connection structure 116, making the structure compact and optimizing the internal space layout of the floor brush.

[0083] See Figure 1 , Figure 2 , Figure 6In one embodiment, the first connector 117 includes a first connecting segment 123 and a second connecting segment 124 that are fixedly connected; the first connecting segment 123 is fixedly connected to the first end 104 and is located between the rotor housing 102 and the second connecting segment 124; the second connecting segment 124 is connected to the second connector 118 through the third bearing 120 and is connected to the motor mounting bracket 119; wherein the outer diameter of the first connecting segment 123 is larger than the outer diameter of the second connecting segment 124.

[0084] The first connecting member 117 is designed as a stepped shaft, including a first connecting section 123 and a second connecting section 124. The first connecting section 123 is close to the rotor housing 102 and has a larger outer diameter. It is firmly fixed to the first end 104 of the fixed shaft 103 to limit the axial movement of the second connecting member 118 along the fixed shaft 103. The outer diameter of the second connecting section 124 is smaller than that of the first connecting section 123. The inner ring of the third bearing 120 is connected to the second connecting section 124 via a spline 121. The end of the second connecting section 124 away from the first connecting section 123 is used to connect to the motor mounting bracket 119.

[0085] By setting a thicker first connecting section 123, the connection strength with the fixed shaft 103 is ensured, while the axial position of the second connecting member 118 is also restricted; by setting a thinner second connecting section 124, a smaller third bearing 120 can be selected, and radial installation space is provided for the externally fitted second connecting member 118 and sealing structure 125.

[0086] See Figure 1 , Figure 2 , Figure 6 In one embodiment, a sealing structure 125 is provided between the second connector 118 and the roller brush to seal the radial gap between the second connector 118 and the roller brush.

[0087] This improves the sealing and waterproof performance of the roller brush motor 100, minimizing the entry of moisture into the roller brush motor 100 through the connection points, thereby enhancing the reliability and stability of the roller brush motor 100.

[0088] An annular sealing groove (not shown) is provided on the outer peripheral surface of the second connector 118. A sealing structure 125, such as a sealing ring, is installed in the sealing groove. When the inner hole of the end of the roller brush is fitted with the second connector 118, a radial gap is formed between the inner wall of the inner hole of the roller brush and the outer wall of the second connector 118. The installed sealing structure 125 is compressed in this gap, and the rebound force generated by its elastic deformation makes it fit tightly against the inner wall of the roller brush and the sealing groove wall of the second connector 118, thereby forming a radial contact seal.

[0089] By setting a sealing structure 125, the rotational gap between the roller brush and the second connector 118 is effectively sealed, preventing sewage, dust and other impurities from entering the interior of the roller brush motor 100 and improving the service life of the roller brush motor 100.

[0090] See Figures 2 to 4 In one embodiment, the wire channel 105 forms an L-shaped channel, and the fixed shaft 103 is an injection-molded integral structure.

[0091] The integral conductor channel 105, formed by the interconnected radial first hole 106 and axial second hole 107, is L-shaped in space. The first hole 106 forms the short side branch of the "L," and the second hole 107 forms the long side branch. The connection between the two forms a corner, and the lead wire follows the trajectory of this L-shaped channel, achieving a change from radial to axial. This L-shaped channel is a specific implementation of the end-center opening wire-passing structure inside an engineering plastic shaft, ensuring that the lead wire is led out from the axial center position.

[0092] By designing this L-shaped channel, the lead wire can complete the direction switching with a shorter path, reducing the detour space required inside the fixed shaft 103. This satisfies the design goal of a compact structure and also helps to reduce the impact of the internal opening on the strength of the fixed shaft 103.

[0093] The fixed shaft 103 is an injection-molded one-piece structure, which means that the entire fixed shaft 103, including its various shaft segments, limiting parts, journals and internal wire channels 105 and all other geometric features, is a single, complete part obtained by injecting molten engineering plastic into the mold cavity in one mold.

[0094] Thus, manufacturing the fixed shaft 103 through injection molding improves the dimensional accuracy and consistency of the fixed shaft 103, eliminates the cumulative assembly error of assembling multiple parts, provides a good benchmark for the assembly of the roller brush motor 100, and helps to ensure the smooth operation of the roller brush motor 100. The one-piece fixed shaft 103 has no connecting interface, has good overall rigidity and strength, and can better withstand complex loads, enhancing the structural integrity and reliability of the fixed shaft 103. It simplifies multiple processing steps into one molding, improving production efficiency and reducing costs.

[0095] See Figure 1 This application also provides a floor brush assembly (not shown) for a cleaning device, including a floor brush housing (not shown), a roller brush, and a roller brush motor 100 as described in the above embodiments. The roller brush is sleeved on the roller brush motor 100, and the roller brush motor 100 is connected to the floor brush housing. The roller brush motor 100 is used to drive the roller brush to rotate.

[0096] By applying the roller brush motor 100 to the floor brush assembly, the brushless direct drive motor provides smooth power. The two ends of the roller brush are supported by the connection structure 116 and the transmission structure 108 respectively to ensure stable operation of the roller brush. The sealed design in the above embodiment enables the roller brush motor 100 to work reliably in the high moisture environment of the floor brush assembly, with low operating noise and vibration. The compact size of the roller brush motor 100 is suitable for the narrow space of the floor brush housing.

[0097] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications or equivalent substitutions made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A roller brush motor, characterized in that, It includes a stator, a rotor housing, and a fixed shaft extending from the stator and the rotor housing; The stator is fixedly mounted on the fixed shaft; The rotor housing is rotatably fitted over the stator and is configured to drive the roller brush of the cleaning equipment to rotate. The first end of the fixed shaft is provided with a wire channel for guiding the stator leads to the outside of the rotor housing; The fixed shaft is made of engineering plastic.

2. The roller brush motor according to claim 1, characterized in that, The wire channel includes a first hole and a second hole that are interconnected. The first hole extends radially from the outer surface of the fixed shaft along the fixed shaft, and the second hole extends axially from the end face of the first end along the fixed shaft.

3. The roller brush motor according to claim 2, characterized in that, After the roller brush motor is assembled to the cleaning device, the axis of the first hole and the axis of the second hole are both located on a vertical plane passing through the axis of the rotor housing.

4. The roller brush motor according to claim 3, characterized in that, The axis of the first hole is parallel to the vertical plane and perpendicular to the axis of the fixed shaft, and the axis of the second hole coincides with the axis of the fixed shaft.

5. The roller brush motor according to claim 2, characterized in that, The fixed shaft passes through the stator and the rotor housing, the second end of the fixed shaft is disposed opposite to the first end, the middle section of the fixed shaft is connected between the first end and the second end, and the radius of the second end is smaller than the radius of the middle section; The first end cover of the rotor housing is connected to the second end via a first bearing, and the second end cover of the rotor housing is connected to the first end via a second bearing; The stator is sleeved on the middle section, the first bearing is sleeved on the second end, and the second bearing is sleeved on the second end.

6. The roller brush motor according to claim 5, characterized in that, The outer peripheral surface of the first end is provided with a first limiting part, and the two opposite ends of the second bearing along the axial direction of the fixed shaft respectively abut against the first limiting part and the second end cover to restrict the movement of the second bearing along the axial direction of the fixed shaft.

7. The roller brush motor according to claim 6, characterized in that, The outer peripheral surface of the first end is also surrounded by a second limiting part, the first limiting part and the second limiting part are spaced apart along the axial direction of the fixed shaft, and the first hole is located between the first limiting part and the second limiting part; One end of the stator along the axial direction of the fixed shaft abuts against the side of the second limiting part away from the first limiting part, so as to position the stator along the axial direction of the fixed shaft.

8. The roller brush motor according to claim 7, characterized in that, The second end cap is provided with a third limiting part extending axially along the fixed shaft on the side facing the stator. The third limiting part is arranged around the second bearing to limit the radial movement of the bearing along the fixed shaft. The inner diameter of the third limiting part gradually increases along the axial direction of the fixed shaft from the end near the second end cover to the end near the stator.

9. The roller brush motor according to claim 2, characterized in that, The first hole is provided in three evenly spaced circumferentially around the first end; The stator is provided with three-phase windings, and the three-phase windings respectively lead out U-phase leads, V-phase leads, and W-phase leads. The U-phase leads, V-phase leads, and W-phase leads are respectively inserted into the corresponding first holes and all extend out of the first ends from the second holes; or The stator is provided with a position detection unit, and the position detection unit has a power positive line, a power negative line and a signal line leading out. The power positive line, the power negative line and the signal line are respectively inserted into the corresponding first hole, and all extend out of the first end from the second hole.

10. The roller brush motor according to claim 1, characterized in that, The roller brush motor also includes a transmission structure located at the second end of the fixed shaft. The transmission structure is fixedly connected to the rotor housing and detachably fixedly connected to the roller brush. The transmission structure is fixedly connected to the first end cover of the rotor housing, and the first end cover is connected to the fixed shaft through a first bearing.

11. The roller brush motor according to claim 1, characterized in that, The roller brush motor further includes a connection structure disposed at the first end and located outside the rotor housing, the connection structure including a first connector and a second connector; One end of the first connector is fixedly disposed at the first end, and the other end is connected to the motor mounting bracket of the cleaning equipment; The second connector is rotatably fitted onto the first connector via a third bearing, and the roller brush is fitted onto the outer circumferential surface of the second connector and seals against the second connector.

12. The roller brush motor according to claim 11, characterized in that, The first connector includes a first connecting segment and a second connecting segment that are fixedly connected. The first connecting segment is fixedly connected to the first end and is located between the rotor housing and the second connecting segment; The second connecting segment is connected to the second connecting member via the third bearing and is also connected to the motor mounting bracket; The outer diameter of the first connecting segment is larger than the outer diameter of the second connecting segment.

13. The roller brush motor according to claim 11, characterized in that, A sealing structure is provided between the second connector and the roller brush to seal the radial gap between the second connector and the roller brush.

14. The roller brush motor according to claim 1, characterized in that, The conductor channel forms an L-shaped channel, and the fixed shaft is an injection-molded integral structure.

15. A floor brush assembly for a cleaning device, characterized in that, The brush includes a floor brush housing, a roller brush, and a roller brush motor as described in any one of claims 1-14, wherein the roller brush is mounted on the roller brush motor, the roller brush motor is connected to the floor brush housing, and the roller brush motor is used to drive the roller brush to rotate.

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