JP7515056B2 - Scraping roller unit and suction tool equipped with the scraping roller unit - Google Patents

Description

The present invention relates to a scraping roller unit that scrapes off dust on a floor surface and a suction tool equipped with the scraping roller unit.

Various suction tools that can be attached to suction-type cleaners have been developed (see Patent Document 1). The suction tool of Patent Document 1 has a housing that forms a suction space that opens downward so that dust on the floor surface can be sucked in, and a flow path that opens into the suction space so that the dust sucked into the suction space can flow to the cleaner. The suction tool further has a scraping roller that is rotatably held within the suction space of the housing. In detail, the scraping roller is held so as to contact the floor surface through an opening at the lower end of the suction space, and is extended in the width direction of the suction tool within the suction space.

The scraping roller inside the housing scrapes off dust on the floor as it rotates. The scraped off dust is then sucked into the cleaner through a flow path.

JP 2011-188951 A

The suction tool of Patent Document 1 employs a structure in which the scraping roller is supported at both ends. In this case, a rotating shaft for transmitting driving force to the scraping roller protrudes from both ends of the scraping roller. By providing bearings adjacent to both ends of the scraping roller and configuring the bearings to be connectable to the housing, the scraping roller is supported at both ends by the housing.

However, due to design requirements for the suction tool, a structure in which the scraping roller is supported at one end is sometimes preferable to a structure in which the scraping roller is supported at both ends. In a configuration in which the scraping roller is supported at one end, the amount of tilt of the scraping roller is greater than in a structure in which the scraping roller is supported at both ends. The greater the tilt of the scraping roller, the greater the load on the bearings.

The present invention aims to provide a technology that reduces the load on the bearings in a structure in which the scraping roller is supported by a cantilever.

A scraping roller unit according to one aspect of the present invention is configured to be cantilever-supported by a housing in which a suction space opening downward is defined. The scraping roller unit includes a rotating shaft , a scraping roller fixed to the rotating shaft , a bearing through which the rotating shaft is inserted , and a tilt suppressing part fitted to the rotating shaft on the opposite side of the bearing from the scraping roller . The outer diameter of the bearing is larger than the diameter of the outer circumferential surface of the scraping roller . The bearing is configured such that , when the scraping roller unit is attached to the housing , the outer circumferential surface of the bearing is held in the housing in a state in which it is in contact with the housing . The tilt suppressing part is formed such that, when the scraping roller unit is attached to the housing, the outer circumferential surface of the tilt suppressing part is held in the housing at a position spaced apart from the bearing .

According to the above configuration, the outer diameter of the bearing is larger than the diameter of the outer peripheral surface of the scraping roller, so that the area in contact with the housing when the scraping roller unit is attached to the housing (i.e., the outer peripheral surface of the bearing) is wider. Therefore, even if an external force is applied to tilt the scraping roller, the force acting on the outer peripheral surface of the bearing can be dispersed. As a result, the load on the bearing is reduced.

When the scraping roller unit is attached to the housing, the outer peripheral surface of the tilt suppression portion is connected to the housing at a position spaced apart from the bearing, so that the rotating shaft is held by the housing at two positions spaced apart in the axial direction of the scraping roller unit, thereby suppressing tilting of the rotating shaft and the scraping roller fixed to the rotating shaft.

A scraping roller unit according to another aspect of the present invention is configured to be cantilever-supported by a housing in which a suction space opening downward is defined. The scraping roller unit includes a rotating shaft, a scraping roller fixed to the rotating shaft, and a bearing through which the rotating shaft is inserted. The outer diameter of the bearing is larger than the diameter of the outer circumferential surface of the scraping roller. The bearing is configured to be held in the housing with the outer circumferential surface of the bearing in contact with the housing when the scraping roller unit is attached to the housing. The scraping roller has a base end that opens toward the bearing. The rotating shaft is inserted into the scraping roller through an opening in the base end of the scraping roller. The scraping roller unit further includes an axial vibration prevention portion fixed to a tip end surface of the bearing that faces the base end of the scraping roller. The scraping roller is fixed to the rotating shaft at a position closer to a middle position in the axial direction of the scraping roller than the base end and tip of the scraping roller. The axial vibration prevention portion protrudes from the tip surface into the scraping roller, and is fitted onto the rotating shaft at a position within the scraping roller closer to the tip than the base end of the rotating shaft , thereby preventing axial vibration of the rotating shaft and holding the rotating shaft at a position adjacent to the fixed portion of the scraping roller relative to the rotating shaft .

According to the above configuration, even if an axial vibration prevention part is provided to prevent axial vibration of the rotating shaft, the axial length of the scraping roller unit is not increased because the axial vibration prevention part is inserted into the scraping roller. Since the axial vibration prevention part is configured to hold the rotating shaft at a position adjacent to the fixing part of the scraping roller relative to the rotating shaft, the holding part of the bearing relative to the rotating shaft is also close to the middle position in the axial direction of the scraping roller. Therefore, like the fixing part of the scraping roller relative to the rotating shaft, the bearing is not subjected to an excessively large load even if an external force acts on either the base end or the tip end of the scraping roller.

A scraping roller unit according to yet another aspect of the present invention is configured to be cantilevered by a housing in which a suction space opening downward is defined. The scraping roller unit includes a rotating shaft, a scraping roller fixed to the rotating shaft, and a bearing through which the rotating shaft is inserted. The outer diameter of the bearing is larger than the diameter of the outer circumferential surface of the scraping roller. The bearing is configured to be held in the housing with the outer circumferential surface of the bearing in contact with the housing when the scraping roller unit is attached to the housing. The scraping roller has a base end that opens toward the bearing. The rotating shaft is inserted into the scraping roller through the opening at the base end of the scraping roller. The scraping roller unit further includes an axial vibration prevention part fixed to the tip surface of the bearing facing the base end of the scraping roller, a tilt suppression part that is fitted to the rotating shaft on the opposite side of the scraping roller with respect to the bearing , and suppresses tilting of the rotating shaft by being held by the housing at a position where the outer circumferential surface is separated from the bearing when the scraping roller unit is attached to the housing , a first reinforcing part fixed to the tip surface so that an external force applied to the axial vibration prevention part is received by the tip surface of the bearing , and a second reinforcing part fixed to the base end surface so that an external force applied to the tilt suppression part is received by the bearing at the base end surface opposite to the tip surface. The axial vibration prevention part protrudes from the tip surface into the scraping roller, and is fitted to the rotating shaft at a position closer to the tip than the base end of the rotating shaft in the scraping roller, thereby preventing axial vibration of the rotating shaft. The first reinforcing part and the second reinforcing part are arranged at a position where the fixed part of the first reinforcing part to the tip surface does not overlap with the fixed part of the second reinforcing part to the base end surface in the axial direction of the scraping roller unit.

According to the above configuration, the axial vibration prevention part and the tilt suppression part are reinforced by the first reinforcement part and the second reinforcement part, respectively. For example, when an external force acts so as to bend the axial vibration prevention part and the tilt suppression part, the external force is transmitted to the fixed part of the first reinforcement part relative to the tip end face of the bearing and the fixed part of the second reinforcement part relative to the base end face. The load on the axial vibration prevention part and the tilt suppression part is alleviated by receiving the external force also at the tip end face and the base end face of the bearing. The fixed parts of the first reinforcement part and the second reinforcement part do not overlap in the axial direction of the rotating shaft, so that the external force is prevented from acting in a concentrated manner on one part of the bearing.

In the above configuration, the scraping roller may include a plurality of band-shaped brush portions that constitute the outer periphery of the scraping roller so as to scrape off dust on the floor surface. The plurality of brush portions may be spaced apart in the circumferential direction of the scraping roller, and may each extend in a spiral shape in the axial direction of the scraping roller so that any part of the plurality of brush portions is in contact with the floor surface during one rotation of the scraping roller.

According to the above configuration, the multiple brush parts are spaced apart in the circumferential direction of the scraping roller, so the scraping roller has less resistance from the floor surface compared to a structure in which the entire outer periphery of the scraping roller is made up of brush parts. Although the multiple brush parts are spaced apart in the circumferential direction of the scraping roller, any part of the multiple brush parts is in contact with the floor surface while the scraping roller rotates once. Therefore, the scraping roller does not become separated from the floor surface. A sudden decrease in the resistance that the scraping roller receives from the floor surface is avoided, so vibration of the scraping roller and noise from the scraping roller are suppressed.

In the above configuration, the scraping roller may include a band-shaped brush portion that constitutes the outer periphery of the scraping roller so as to scrape off dust on the floor surface. The brush portion may extend in a spiral shape so that the lead angle gradually increases from the base end side to the tip end side of the scraping roller.

With the above configuration, the lead angle of the band-shaped brush portion is relatively small at the base end side of the tapered tube portion, so that a large force can be applied in the direction of the tip of the scraping roller to dust that comes into contact with the brush portion at the base end side of the scraping roller.

The lead angle of the brush part gradually increases from the base end side to the tip end side of the tapered tube part. Therefore, even if the brush part is spirally extended over almost the entire length of the tapered tube part, the overall length of the brush part will not be longer than that of a brush part that is spirally wound around the tapered tube part while maintaining a small lead angle at the base end side of the tapered tube part. In this case, the travel distance of dust moving from the base end side of the tapered tube part along the brush part will be relatively short.

In the above configuration, the scraping roller may include a brush portion that configures an outer periphery of the scraping roller so as to scrape off dust on a floor surface. The brush portion may include a plurality of brush bristles arranged at a density of 130 bristles/ ^mm2 or more in the area where the brush portion is provided.

According to the above configuration, the brush bristles are arranged at a density of 130 bristles/mm2 or ^more in the area where the brush portion is provided, so that when brush bristles of a typical thickness used for scraping off dust (for example, brush bristles with an apparent outer diameter (i.e., the diameter of the circumscribed circle of the brush bristles) of 0.06 mm to 0.1 mm) are used, the distance between adjacent brush bristles is equal to or less than the diameter of the hair (approximately 0.04 μm). Therefore, hair is less likely to get inside the brush portion.

In the above configuration, the scraping roller unit may further include a pulley attached to the rotating shaft at the base end side relative to the bearing. The bearing may be configured to hold the rotating shaft at a position adjacent to the pulley.

According to the above configuration, the bearing holds the rotating shaft at a position adjacent to the pulley, so axial vibration is suppressed in the part where the pulley is attached. In addition, even if a radial external force acts on the pulley, the load on the bearing (= external force x distance between the pulley and the part where the rotating shaft is held by the bearing) is small.

A scraping roller unit according to yet another aspect of the present invention is configured to be cantilevered by a housing in which a suction space opening downward is defined. The scraping roller unit includes a rotating shaft, a scraping roller fixed to the rotating shaft, and a bearing through which the rotating shaft is inserted. The outer diameter of the bearing is larger than the diameter of the outer circumferential surface of the scraping roller. The bearing is configured to be held in the housing with the outer circumferential surface of the bearing in contact with the housing when the scraping roller unit is attached to the housing. The scraping roller is fixed to the rotating shaft at a position closer to a middle position in the axial direction of the scraping roller than the base end and the tip end of the scraping roller.

According to the above configuration, the scraping roller is fixed to the rotating shaft at a position closer to the midpoint in the axial direction of the scraping roller than the base end of the scraping roller. Therefore, when the scraping roller receives an external force in the radial direction at the tip of the scraping roller, the load acting on the fixed part of the scraping roller (= external force x distance from the tip of the scraping roller to the fixed part) does not become excessively large. In addition, the scraping roller is fixed to the rotating shaft at a position closer to the midpoint in the axial direction of the scraping roller than the tip of the scraping roller. Therefore, when the scraping roller receives an external force in the radial direction at the base end of the scraping roller, the load acting on the fixed part of the scraping roller (= external force x distance from the base end of the scraping roller to the fixed part) does not become excessively large.

In the above configuration, the scraping roller may include a cylindrical portion into which the rotating shaft is inserted, a brush portion attached to the outer periphery of the cylindrical portion to scrape off dust, and a fixed portion configured to be fixed to the rotating shaft within the cylindrical portion. The cylindrical portion and the fixed portion may be integrally molded.

With the above configuration, the tube portion and the fixed portion are integrally molded, so the scraping roller has higher strength than a structure in which they are formed separately.

In the above configuration, the fixing portion may be fixed to the rotating shaft by injecting resin around the rotating shaft.

According to the above configuration, the fixing part is fixed to the rotating shaft by injecting resin around the rotating shaft, so that a high connection strength is obtained between the fixing part and the rotating shaft.

A suction tool according to another aspect of the present invention includes a housing defining a suction space that opens downward, and the above-mentioned scraping roller unit . The scraping roller is disposed in the suction space . The housing includes a recessed accommodation portion that is adjacent to the suction space in the width direction of the housing so as to support a bearing of the scraping roller unit . The accommodation portion is configured to abut against an upper portion of the bearing, which is a portion above the rotating shaft, on the suction space side and on the opposite side to the suction space , and is configured to abut against a lower portion of the bearing, which is a portion below the rotating shaft , on the opposite side to the suction space, but not on the suction space side.

According to the above configuration, the upper and lower parts of the bearing abut against the housing part on the side opposite to the suction space side, so that the bearing is prevented from displacing in the opposite direction to the suction space. On the other hand, although the displacement of the upper part of the bearing toward the suction space side is prevented by the housing part abutting against the upper part of the bearing, the displacement of the lower part of the bearing toward the suction space side is permitted. Therefore, the tilting of the bearing is permitted to a certain extent such that only the lower part of the bearing is displaced toward the suction space side without the position of the upper part of the bearing changing substantially. Such tilting of the bearing can occur, for example, when an upward external force acts on the scraping roller arranged in the suction space. In other words, when an upward external force acts on the scraping roller, the above-mentioned tilting of the bearing is permitted to a certain extent, so that the load applied to the housing part and the scraping roller unit is reduced.

In the above configuration, the scraping roller unit may include a protruding portion protruding downward from an outer circumferential surface of the bearing . The housing portion may be configured to abut against the bearing and the protruding portion on a side opposite to the suction space with respect to the bearing and the protruding portion.

With the above configuration, the housing abuts not only against the bearing but also against the protrusion, so that when an external force acts that tends to displace the bearing and the protrusion in the opposite direction to the suction space, the external force is dispersed and the load on the housing is reduced.

In the above configuration , the protruding portion may protrude downward relative to an outer circumferential surface of the lower portion of the bearing . The accommodating portion may be configured to abut against the lower portion of the bearing and the protruding portion on a side opposite to the suction space.

With the above configuration, when a downward external force acts on the scraping roller, a force acts toward the suction space on the upper part of the bearing, and a force acts in the opposite direction to the suction space on the lower part and protruding part of the bearing. At this time, the housing receives these forces at the part that contacts the upper part of the bearing on the suction space side, and at the part that contacts the lower part of the bearing and the protruding part on the side opposite the suction space. In this way, the housing can receive forces at multiple points, so the pressure at each contact point is smaller and the load on the housing is reduced.

With regard to the above configuration, the suction tool may further include a pressing portion that presses the bearing against the housing portion.

According to the above configuration, the pressing portion presses the bearing against the housing portion, so no gap is created between the shaft portion and the housing in the pressing direction of the pressing portion, and the bearing is maintained in contact with the housing. Therefore, noise caused by the bearing coming into contact with and separating from the housing is suppressed.

Regarding the above configuration, the suction tool may include a cushion member interposed between the bearing and the housing.

With the above configuration, a cushion member is inserted between the housing and the bearing, which reduces noise caused by the bearing coming into contact with the housing.

The scraping roller unit and suction tool described above can reduce the load on the bearing section.

FIG. 1 is a schematic side view of a cleaning machine; FIG. 2 is a schematic exploded perspective view of a suction tool configured to be attachable to a cleaning machine; FIG. 2 is a schematic diagram of the internal structure of the suction tool. FIG. 2 is a schematic bottom view of the suction tool. FIG. 2 is a schematic vertical cross-sectional view of the suction tool. 13 is a schematic plan view of a sliding piece of a cover member configured to be attachable to a main body of a housing of a suction tool. FIG. FIG. 4 is a schematic rear view of the slide piece. FIG. 4 is a schematic bottom view of the slide piece. FIG. 2 is a schematic plan view of a scraping roller unit of the suction tool. FIG. 2 is a schematic cross-sectional view of a scraping roller unit. FIG. 2 is a schematic development view of a scraping roller unit. 11 is a schematic diagram illustrating a protruding direction of a rib of a first reinforcing portion of the scraping roller unit. FIG. 11 is a schematic diagram showing a protruding direction of a rib of a second reinforcing portion of the scraping roller unit. FIG. 4 is a schematic diagram of a mounting structure of the scraping roller unit to the housing. FIG. 5A and 5B are schematic diagrams showing forces acting on dust when the dust is wound around a scraping roller. FIG. 2 is a schematic cross-sectional view of a scraper roller unit mounted in a housing lined with a cushioning material. FIG. 11 is a schematic cross-sectional view of another scraping roller unit.

Figure 1 is a schematic side view of a cleaner 101 to which a suction tool 100 is attached. Figure 2 is a schematic exploded perspective view of the suction tool 100. Figure 3 is a schematic plan view showing the internal structure of the suction tool 100. Figure 4 is a schematic bottom view of the suction tool 100. Figure 5 is a schematic vertical cross-sectional view of the suction tool 100. The cleaner 101 and the suction tool 100 will be described with reference to Figures 1 to 5.

The cleaner 101 comprises a cleaning main body 102 incorporating a suction fan (not shown) and a motor (not shown) for driving the suction fan, a hose 103 extending from the cleaning main body 102 to the suction tool 100, and an operation unit 104 provided on the hose 103. The tip of the hose 103 is configured to be connectable to the suction tool 100. The operation unit 104 is configured to operate the cleaning main body 102 and the suction tool 100 in response to a user's operation. Electrical wiring from the cleaning main body 102 and the suction tool 100 to the operation unit 104 is performed along the hose 103.

The suction tool 100 is attached to the end of the hose 103 to obtain a suction area wider than the internal space of the hose 103. The suction tool 100 is configured to scrape off and suck up dust on the floor surface.

The suction tool 100 has a resin housing 120 that defines a suction space 110 that opens downward to suck in dust on the floor surface, and a pair of scraping roller units 131, 132 held by the housing 120. In addition, the suction tool 100 has a drive mechanism 150 that is configured to drive these scraping roller units 131, 132.

The housing 120 has a shape that is wider in the width direction than in the front-to-rear direction in order to obtain a suction space 110 that is wide in the width direction. The suction space 110 is formed on the front side of the housing 120.

2, the housing 120 includes a main body 121 having a generally C-shape that opens forward in a plan view, and a cover member 122 configured to be attached to the main body 121. In addition, the housing 120 includes upper claws 141-144 and a mounting plate 145 for attaching the cover member 122 to the main body 121.

The main body 121 includes a pair of side portions 123, 124 spaced apart from each other to sandwich the suction space 110 in the width direction, and a rear portion 125 located on the rear side of the side portions 123, 124 and the suction space 110 (i.e., the cleaning main body 102 side). The side portions 123, 124 and the rear portion 125 have a hollow structure. The internal spaces of the side portions 123, 124 and the rear portion 125 are used to accommodate the drive mechanism 150 within the main body 121. The front portions of the outer wall portion 126 and the lower wall portion 127 (i.e., the portions that overlap the suction space 110 in the width direction) constitute the side portions 123, 124. The remaining portions (i.e., the rear portions) of the outer wall portion 126 and the lower wall portion 127 constitute the rear portion 125.

The side portion 123 is disposed on the left side of the suction space 110. The side portion 123 is composed of the front portions of the outer wall portion 126 and the lower wall portion 127, the front wall portion 171, the inner wall portion 172, and the cover member 173.

The front portion of the outer wall 126 is erected so as to block the internal space of the side portion 123 from the outside in the width direction of the suction tool 100. The front portion of the lower wall 127 is arranged so as to block the internal space of the side portion 123 from below.

The front wall 171 is a portion that closes the internal space of the side portion 123 from the front side. In detail, the front wall 171 includes an upper portion 181 that protrudes forward while curving downward from the upper portion of the rear portion 125, and a lower portion 182 that is connected to the lower end of the upper portion 181 in an upright position. The upper portion 181 is a portion on which the cover member 122 is placed. The lower portion 182 has a predetermined thickness in the front-rear direction and has an upper end surface 183 that protrudes forward from the lower end of the upper portion 181. The upper end surface 183 of the lower portion 182 is used to support the lower end of the cover member 122. The upper end surface 183 of the lower portion 182 has an engagement hole portion 184 that opens upward. The engagement hole portion 184 is used to fix the lower portion of the cover member 122 to the main body portion 121.

The inner wall portion 172 is a portion that forms the left end of the internal space of the side portion 123. The inner wall portion 172 has a predetermined thickness in the width direction of the suction tool 100. A through hole is formed in the inner wall portion 172, penetrating the inner wall portion 172 in the thickness direction (i.e., the width direction of the suction tool 100). The scraping roller unit 131 is inserted into the internal space of the side portion 123 through this through hole. The inner edge portion of the through hole is configured to hold the scraping roller unit 131. The structure for holding the scraping roller unit 131 will be described in detail separately.

The upper part of the outer peripheral surface 185 of the inner wall portion 172 protrudes forward while curving downward from the upper part of the rear portion 125, similar to the upper part 181 of the front wall portion 171. A recess 186 (see FIG. 3) that is complementary to the cover member 173 is formed at the upper end of the outer peripheral surface 185 (i.e., the part adjacent to the front side of the upper part of the rear portion 125). The cover member 173 is fitted into the recess 186 (see FIG. 2). When the cover member 173 is removed from the recess 186, a screw hole 187 (see FIG. 3) formed in the recess 186 is exposed. The screw hole 187 is used to connect the housing 120 and the scraping roller unit 131.

The right side 124 has a structure that is symmetrical with respect to the left side 123. The description of the side 123 is applicable to the side 124, taking into account the symmetry of the sides 123 and 124.

The rear portion 125 has the rear portions of the outer wall portion 126 and the lower wall portion 127, the upper wall portion 191, the rear wall portion 192, the front wall portion 240, and a connection recess 193 used to connect the hose 103 and the suction tool 100.

The rear portion of the outer wall 126 is erected so as to block the internal space of the rear portion 125 from the outside in the width direction of the suction tool 100. The rear portion of the lower wall 127 is provided so as to block the internal space of the rear portion 125 from below.

The upper wall portion 191 is provided between the left and right outer wall portions 126 so as to close the internal space of the rear portion 125 from above. The upper wall portion 191 has a predetermined thickness in the vertical direction and forms a front edge surface 198 (see FIG. 2).

The rear wall portion 192 is configured to close the internal space of the rear portion 125 from the rear side. In detail, the rear wall portion 192 is connected to the upper wall portion 191 in an upright position on the side opposite the front edge surface 198, and forms a corner portion with the upper wall portion 191.

The connection recess 193 is formed at approximately the center of the housing 120 in the width direction, recessed forward and downward from the corner formed by the rear wall 192 and the upper wall 191. The connection recess 193 is used to connect the suction tool 100 and the hose 103.

The connection recess 193 includes a pair of side walls 194, 195 spaced apart from each other in the width direction, and a bottom wall 196 provided between the bottom ends of the side walls 194, 195. An opening 197 (see FIG. 3) is formed in the bottom wall 196. A flow path 241 (see FIG. 5) extending from the opening 197 and connecting to the suction space 110 is formed in the rear portion 125 (not shown). The opening 197 is a portion that connects to the internal space of the hose 103.

The front wall 240 is configured to close the internal space of the rear section 125 from the front side, and separates the internal space of the rear section 125 from the suction space 110. In other words, the front wall 240 forms the rear end of the suction space 110. The above-mentioned flow path 241 opens on the front wall 240 (approximately at the center position in the width direction of the suction tool 100).

The upper claws 141-144 and the mounting plate 145 (see FIG. 2) protrude forward from the front edge surface 198 of the upper wall portion 191. The mounting plate 145 is a substantially triangular plate portion protruding from the front edge surface 198 above the suction space 110. The mounting plate 145 has a length in the width direction substantially equal to that of the suction space 110. The mounting plate 145 is provided at a height substantially equal to that of the lid member 173 attached to the upper end of the inner wall portion 172. The left end of the mounting plate 145 is located to the right of the left lid member 173, and a gap is formed between the left end of the mounting plate 145 and the left lid member 173. The right end of the mounting plate 145 is located to the left of the right lid member 173, and a gap is formed between the right end of the mounting plate 145 and the right lid member 173.

The upper claw 141 protrudes forward from the front edge surface 198 above the gap between the left end of the mounting plate 145 and the left cover member 173. The upper claw 143 protrudes forward from the front edge surface 198 at a position spaced to the left of the upper claw 141. The upper claws 142 and 144 protrude from the front edge surface 198 in a layout that is symmetrical to the upper claws 141 and 143, respectively. The description of the upper claws 141 and 143 is applicable to the upper claws 142 and 144, taking symmetry into consideration.

The cover member 122 (see FIG. 2) has a main plate portion 211, a pair of fixed flap portions 212, 213, a pair of lower claw portions 214, 215, and a pair of slide pieces 216, 217.

The main plate portion 211 is a portion that is placed on the placement plate 145 when the cover member 122 is attached to the main body portion 121. The main plate portion 211 is configured to block the front and upper sides of the suction space 110, and has a length in the width direction that is approximately equal to that of the suction space 110. The main plate portion 211 includes an upper plate portion 221 that curves forward and downward with approximately the same curvature as the upper portion of the side portion 123, and a lower plate portion 222 that protrudes downward from the lower edge of the upper plate portion 221 and blocks the front side of the suction space 110. The upper plate portion 221 covers the left and right upper claws 141, 142 from above when the cover member 122 is attached to the main body portion 121.

The fixed flap portion 212 protrudes leftward from the left edge of the upper plate portion 221. The fixed flap portion 212 is configured to be placed on the left side portion 123 when the cover member 122 is attached to the main body portion 121. In other words, the fixed flap portion 212 has a curved shape that follows the curved shapes of the outer peripheral surface 185 of the inner wall portion 172 and the upper portion 181 of the front wall portion 171.

A groove 223 extending in the width direction of the suction tool 100 is formed at the upper end of the fixed flap portion 212. The groove 223 has a depth such that an opening is formed at the right end of the groove 223 that connects to the space below the upper claw 141.

A slide piece 216 is attached to the groove 223. The slide piece 216 is configured to be movable in the width direction of the suction tool 100 along the groove 223. In FIG. 2, the slide piece 216 is located at a position protruding to the left from the left end edge of the fixed flap portion 212, and is movable to the right from the position shown in FIG. 2. A schematic plan view of the slide piece 216 is shown in FIG. 6. A schematic rear view of the slide piece 216 is shown in FIG. 7. A schematic bottom view of the slide piece 216 is shown in FIG. 8. The cover member 122 will be further described with reference to FIGS. 2, 6 to 8.

The slide piece 216 includes a roughly rectangular plate-shaped operation piece 231 that is operated by the user, a protruding piece 232 that protrudes to the right from the right end of the operation piece 231, and an engagement portion 233 that is provided on the underside of the operation piece 231.

The protruding piece 232 is configured to enter the space below the upper claw 141 through an opening formed at the right end of the groove portion 223 when the user operates the operating piece 231 to move the slide piece 216 to the right.

The engagement portion 233 is formed at a position where it engages with the upper claw 143 when the user operates the operation piece 231 to move the slide piece 216 to the right. In detail, the engagement portion 233 has a lower plate portion 235 provided at a position spaced downward from the lower surface of the operation piece 231, and a connecting plate portion 236 that connects the lower plate portion 235 and the upper claw 143. When the user operates the operation piece 231 to move the slide piece 216 to the right, the upper claw 143 enters into the space formed between the lower plate portion 235 and the lower surface of the operation piece 231.

The lower claw portion 214 protrudes downward from the lower edge of the fixed flap portion 212. The lower claw portion 214 is inserted into the engagement hole portion 184 of the left side portion 123 when the cover member 122 is attached to the main body portion 121.

The fixed flap portion 213, the lower claw portion 215, and the sliding piece 217 have a structure that is symmetrical to the fixed flap portion 212, the lower claw portion 214, and the sliding piece 216. The explanations of the fixed flap portion 212, the lower claw portion 214, and the sliding piece 216 are applied to the fixed flap portion 213, the lower claw portion 215, and the sliding piece 217, taking symmetry into consideration.

As shown in FIG. 3, the drive mechanism 150 has a pair of motors 151, 152 and a pair of drive belts 153, 154. The motors 151, 152 and the drive belts 153, 154 are disposed in the internal space of the main body 121. The motor 151 and the drive belt 153 are used to drive the scraping roller unit 131. The motor 152 and the drive belt 154 are used to drive the scraping roller unit 132.

The motor 151 has a main body 155 and a motor shaft 156 that protrudes from the main body 155 toward the left outer wall 126. The motor 151 is disposed in the internal space of the rear portion 125 on the left side of the connection recess 193. The motor 151 is fixed so that the motor shaft 156 is approximately parallel to the rotation axis of the scraping roller unit 131. A pulley 157 is attached to the motor shaft 156.

The drive belt 153 is wound around a pulley 157 and extends from the internal space of the rear portion 125 to the internal space of the side portion 123. The drive belt 153 is connected to the scraping roller unit 131 so that the driving force of the motor 151 is transmitted to the scraping roller unit 131.

The motor 152 and drive belt 154 are disposed in the internal space on the right side of the connection recess 193. The right-side motor 152 and drive belt 154 have a structure that is symmetrical with respect to the left-side motor 151 and drive belt 153. The description of the left-side motor 151 and drive belt 153 applies to the right-side motor 152 and drive belt 154, taking symmetry into consideration.

The scraping roller unit 131 is supported by a cantilever on the side portion 123, and is configured to rotate by the driving force transmitted from the motor 151 through the drive belt 153. A schematic plan view of the scraping roller unit 131 is shown in FIG. 9. A schematic cross-sectional view taken along the line X-X shown in FIG. 9 is shown in FIG. 10. A schematic development view of the scraping roller unit 131 is shown in FIG. 11. The scraping roller unit 131 will be described with reference to FIGS. 2, 3, 9 to 11.

The scraping roller unit 131 has a resin scraping roller 310, a metal rotating shaft 320, a resin bearing unit 330, and a pulley 340.

The scraping roller 310 includes a cylindrical portion 311, six brush portions 312, a tip cap 313, and a fixed portion 411 (see FIG. 10), and is disposed in the suction space 110 as shown in FIG. 2. The cylindrical portion 311 is a portion that holds the brush portions 312. The brush portions 312 are a portion for scraping off dust on the floor surface, and form the outer periphery of the scraping roller 310. The tip cap 313 is provided to prevent the brush portions 312 from moving in the axial direction of the cylindrical portion 311. The fixed portion 411 is a portion that fixes the scraping roller 310 to the rotating shaft 320.

When the scraping roller unit 131 is attached to the side portion 123, the base end 314 of the tube portion 311 is disposed adjacent to the side portion 123 in the width direction of the suction tool 100. The tube portion 311 extends rightward from the base end 314 to a position close to the center position of the suction space 110. The tip end 315 of the tube portion 311 is located to the left of the center position of the suction space 110 in the width direction. The tip end 315 and base end 314 of the tube portion 311 are open. The tube portion 311 has a tapered shape that gradually becomes narrower from the base end 314 toward the tip end 315.

The cylindrical portion 311 is integrally molded with the fixed portion 411 using resin. In detail, the cylindrical portion 311 and the fixed portion 411 are formed by injection molding molten resin with a part of the rotating shaft 320 placed in the cavity of a mold for the cylindrical portion 311 and the fixed portion 411. As a result of this injection molding, the fixed portion 411 is connected to the outer circumferential surface of the rotating shaft 320. The fixed portion 411 is connected to the rotating shaft 320 at a position closer to the middle position in the axial direction of the cylindrical portion 311 than the tip end 315 and base end 314 of the cylindrical portion 311 (i.e., the scraping roller 310).

Six spirally curved grooves 317 (see FIG. 11) are formed on the outer circumferential surface 316 of the tube portion 311 over the entire length of the tube portion 311. Each of these grooves 317 is used to attach the brush portion 312. In other words, the brush portion 312 is formed in a spiral band shape so that it fits into the grooves 317.

The spiral direction of these grooves 317 is set so that when the scraping roller 310 rotates in the direction shown in FIG. 2, the brush portion 312 contacts the floor surface at the base end side of the scraping roller 310, and then the brush portion 312 contacts the floor surface at the tip end side of the scraping roller 310.

These grooves 317 are formed at approximately equal intervals in the circumferential direction of the tube portion 311 (i.e., at a central angle of approximately 60° (=360°/6 pieces)). These grooves 317 are formed so that when the base end of the brush portion 312 that first contacts the floor surface contacts the floor surface, the tip of the following brush portion 312 contacts the floor surface at the same time. In other words, these grooves 317 are formed so that the base end of one brush portion 312 overlaps with the tip of the brush portion 312 that contacts the floor surface following this brush portion 312 in the axial direction of the scraping roller 310. As a result, while the scraping roller 310 rotates once, any part of the six brush portions 312 is in contact with the floor surface. In other words, the scraping roller 310 is not separated from the floor surface.

Each groove 317 is formed so that the lead angle of the brush portion 312 (i.e., the intersection angle of the brush portion 312 with respect to a plane perpendicular to the axis of the tube portion 311) gradually increases from the base end side to the tip end side of the scraping roller 310. The lead angles θp, θd of the brush portion 312 at the base end side and tip end side of the scraping roller 310 are shown in Figure 9 (θp<θd).

The brush portion 312 extends in a spiral shape along the groove portion 317 over substantially the entire length of the tube portion 311. One end of the brush portion 312 in the longitudinal direction protrudes beyond the tip end 315 of the tube portion 311 toward the tip side, as shown in FIG. 10. The other end of the brush portion 312 in the longitudinal direction is located closer to the tip side than the base end 314 of the tube portion 311. The portion between the other end of the brush portion 312 and the base end 314 of the tube portion 311 is used to connect the scraping roller 310 and the bearing unit 330.

The brush portion 312 has a plurality of brush bristles protruding in the radial direction from the outer circumferential surface 316 of the tube portion 311. The length of these brush bristles is approximately uniform. When the scraping roller unit 131 is attached to the side portion 123, these brush bristles come into contact with the floor surface. These brush bristles are made of a material that is soft enough not to damage the floor surface when rubbed against it. These brush bristles are arranged in a spiral band region at a density of 130 bristles/ ^mm2 . The brush bristles may also be of a similar thickness to brush bristles of a general thickness used to scrape off dust (for example, bristles with an apparent outer diameter of 0.06 mm to 0.1 mm). It is preferable that the brush bristles are arranged at a density as high as possible. For example, when brush bristles with an apparent outer diameter of 0.06 mm are used, the brush bristles can be arranged at a density of about 277 bristles/ ^mm2 .

The tip cap 313 is attached to the tip 315 of the tube 311 so that the brush part 312 attached to the groove 317 does not shift toward the tip. The tip cap 313 includes a disk-shaped stopper plate 318 formed to contact the end of the brush part 312 (the part above the tip 315 of the tube 311), and an insertion part 319 that is inserted into the tube 311 through the opening of the tip 315 of the tube 311.

A part of the rotating shaft 320 is inserted into the tubular portion 311 through an opening at the base end 314 of the tubular portion 311. The tip portion of the rotating shaft 320 arranged in the tubular portion 311 is located on the tip side of the midpoint in the axial direction of the tubular portion 311. In a predetermined section around the midpoint in the axial direction of the tubular portion 311, the tip portion of the rotating shaft 320 is connected to the fixed portion 411. In order to increase the connection strength between the fixed portion 411 and the rotating shaft 320, the outer circumferential surface of the rotating shaft 320 is knurled at the connection portion with the fixed portion 411.

The base end portion of the rotating shaft 320 protrudes from the base end portion 314 of the cylindrical portion 311 and is located outside the cylindrical portion 311. A pulley 340 is attached to the base end portion of the rotating shaft 320. In detail, the pulley 340 is attached to the rotating shaft 320 at a position away from the base end portion 314 of the cylindrical portion 311 toward the base end side. A drive belt 153 is wound around the pulley 340 (see FIG. 3).

The bearing unit 330 is disposed between the pulley 340 and the fixed part 411, and the rotating shaft 320 is inserted into the bearing unit 330. The bearing unit 330 is configured to function as a sliding bearing.

The bearing unit 330 includes a main part 331, a base end cap 335, an axial vibration prevention part 370, and a tilt suppression part 333. The main part 331 is a part adjacent to the base end part 314 of the scraping roller 310 (i.e., the base end part 314 of the cylindrical part 311), and has an outer diameter larger than the outer diameter of the cylindrical part 311. The axial vibration prevention part 370 is a part extended from the main part 331 so as to be inserted into the cylindrical part 311, and is provided to suppress the axial vibration of the rotating shaft 320. The tilt suppression part 333 is a cylindrical part protruding from the main part 331 toward the pulley 340 on the opposite side to the scraping roller 310, and is provided to suppress the tilt of the scraping roller unit 131. The base end cap 335 is a member fitted into the tilt suppression part 333, and constitutes a bearing 380 (slide bearing) together with the main part 331.

The main part 331 is a part used for holding by the side part 123 of the housing 120. The main part 331 is attached to the side part 123 so that the rotation axis of the scraping roller 310 is inclined downward toward the approximate center position of the suction space 110 as shown in FIG. 5. As a result, the brush part 312 can contact the floor surface over approximately the entire length of the scraping roller 310 even if the tube part 311 has a tapered shape that becomes thinner toward the tip part 315. Also, the main part 331 is attached to the side part 123 so that the rotation axis of the scraping roller 310 is inclined forward toward the approximate center position of the suction space 110 as shown in FIG. 4. As a result, the part of the suction space 110 that is farther forward from the opening of the flow path 241 on the suction space 110 side (see FIG. 5) is occupied by the scraping roller 310.

As shown in FIG. 10, the main portion 331 includes a plate member 421, an annular outer fitting ring 422, a pair of protruding portions 423, 424, and a thick portion 425. The plate member 421 is a plate-like portion having a thickness that gradually decreases toward the rear (see FIG. 11). The thicknesses of the front and rear ends of the plate member 421 are different to prevent a user from attaching the scraping roller unit 131 to the housing 120 by mistakenly arranging the front and rear directions of the scraping roller unit 131. The outer fitting ring 422 is a ring-like portion that protrudes to the right from the right end face of the plate member 421. The protruding portion 423 is a portion that protrudes upward from the outer peripheral surface of the outer fitting ring 422 at approximately the middle position in the protruding direction of the outer fitting ring 422. The protruding portion 424 is an arc-shaped protrusion that extends along the tip edge of the outer peripheral surface of the outer fitting ring 422. The thick portion 425 is formed adjacent to the outer fitting ring 422.

The front end of the plate member 421 is aligned with the front end of the outer fitting ring 422 in the width direction of the suction tool 100, while the rear part of the plate member 421 protrudes from the rear end of the outer fitting ring 422. The size of the vertical cross section of the plate member 421 is approximately equal to the outer diameter of the outer fitting ring 422, as shown in FIG. 10. The plate member 421 has a shape larger than the base end 314 of the tubular portion 311. A through hole 426 with a diameter larger than the diameter of the rotating shaft 320 is formed approximately at the center of the plate member 421. The rotating shaft 320 is inserted through the through hole 426.

The outer fitting ring 422 protrudes from the tip surface 428 of the plate member 421 (i.e., the surface facing the base end 314 of the tube portion 311) toward the tip side of the scraping roller 310. The outer diameter of the outer fitting ring 422 is larger than the outer diameter of the base end 314 of the tube portion 311, and the inner diameter of the outer fitting ring 422 is approximately equal to the outer diameter of the base end 314 of the tube portion 311. The tip portion of the outer fitting ring 422 is fitted onto the base end 314 of the tube portion 311. The tip edge of the outer fitting ring 422 abuts against the end (base end in the longitudinal direction) of the brush portion 312, preventing the brush portion 312 from shifting toward the base end.

The protrusion 423 is a portion that protrudes upward from the outer peripheral surface of the outer fitting ring 422 at the upper portion of the outer fitting ring 422. In detail, the protrusion 423 protrudes from the tip edge of the outer fitting ring 422 at a position spaced from the base end side. The protrusion 424 is provided in an arc shape along the tip of the outer peripheral surface of the outer fitting ring 422 (see Figures 9 and 10), and protrudes downward from the outer peripheral surface of the outer fitting ring 422 at the lower end of the outer fitting ring 422 (see Figure 10). These protrusions 423, 424 are portions that are used to hold the scraping roller unit 131 by the side portion 123 of the housing 120.

The thick portion 425 is a portion that is located below the cover member 173 (see FIG. 2) when the scraping roller unit 131 is attached to the side portion 123. The thick portion 425 is formed to fill the gap between the outer peripheral surface of the plate member 421 and the inner surface of the side portion 123 (more specifically, the inner surface of the portion that corresponds to the recess 186 (see FIG. 3) into which the cover member 173 is fitted). The thick portion 425 is formed with a screw hole 427 (see FIG. 10) that extends further downward from the lower end of the screw hole 187 formed in the recess 186.

The axial vibration prevention part 370 includes a tip tube part 332 that extends from the tip surface 428 of the plate member 421 toward the tip side coaxially with the through hole 426 of the plate member 421, and a tip cap 334 that is fitted into the tip of the tip tube part 332.

The tip tube portion 332 is inserted into the tube portion 311 through the opening at the base end portion 314 of the tube portion 311. The tip tube portion 332 extends close to the fixed portion 411. The inner diameter of the tip tube portion 332 is larger than the diameter of the rotating shaft 320, and the rotating shaft 320 is inserted into the tip tube portion 332.

The tip cap 334 is a cylindrical member fitted into an annular gap formed between the outer circumferential surface of the rotating shaft 320 and the inner circumferential surface of the tip portion of the tip tube portion 332. The tip cap 334 is adjacent to the fixed portion 411 on the base end side of the fixed portion 411. The inner diameter of the tip cap 334 is approximately equal to the diameter of the rotating shaft 320, and the rotating shaft 320 is fitted into the tip cap 334 at the tip portion of the tip tube portion 332.

The tilt suppression portion 333 protrudes from the base end surface 429 opposite the tip surface 428 of the plate member 421 toward the base end side (i.e., the side opposite the scraping roller 310). The amount by which the tilt suppression portion 333 protrudes from the base end surface 429 is smaller than the amount by which the tip tube portion 332 protrudes from the tip surface 428. The inner diameter of the tilt suppression portion 333 is larger than the diameter of the rotating shaft 320, and the rotating shaft 320 is inserted into the tilt suppression portion 333.

The base end cap 335 is a cylindrical member fitted into the annular gap formed between the outer circumferential surface of the rotating shaft 320 and the inner circumferential surface of the tilt suppression portion 333, and is adjacent to the tip side of the pulley 340. The inner diameter of the base end cap 335 is approximately equal to the diameter of the rotating shaft 320, and the rotating shaft 320 is fitted into the base end cap 335 within the tilt suppression portion 333. In other words, the tilt suppression portion 333 is fitted onto the rotating shaft 320 together with the base end cap 335.

The bearing unit 330 has a first reinforcing part 350 that reinforces the tip tube part 332 and a second reinforcing part 360 that reinforces the tilt suppression part 333. The first reinforcing part 350 has a plurality of ribs 351 that protrude radially from the outer circumferential surface of the tip tube part 332. These ribs 351 are integrated with the outer circumferential surface of the tip tube part 332 and the tip surface 428 of the plate member 421. The second reinforcing part 360 has a plurality of ribs 361 that protrude radially from the outer circumferential surface of the tilt suppression part 333. These ribs 361 are integrated with the outer circumferential surface of the tilt suppression part 333 and the base end surface 429 of the plate member 421. The ribs 361 are shorter than the tilt suppression part 333 in the axial direction of the rotating shaft 320. In other words, the tilt suppression part 333 protrudes toward the base end side more than the ribs 361. The portion of the tilt suppression portion 333 that protrudes toward the base end from the rib 361 is used to support the scraping roller unit 131 by the side portion 123 of the housing 120.

The protruding direction of the rib 351 of the first reinforcing portion 350 and the rib 361 of the second reinforcing portion 360 are set so that the ribs 351, 361 are staggered in the circumferential direction as shown in Figures 12 and 13. Figure 12 is a schematic diagram showing the protruding direction of the rib 351 from the outer peripheral surface of the tip tube portion 332. Figure 13 is a schematic diagram showing the protruding direction of the rib 361 from the outer peripheral surface of the tilt suppression portion 333.

The ribs 351 of the first reinforcing portion 350 protrude from the outer circumferential surface of the tip tube portion 332 in the 0 o'clock, 2 o'clock, 4 o'clock, 6 o'clock, 8 o'clock, and 10 o'clock directions. On the other hand, the ribs 361 of the second reinforcing portion 360 protrude from the outer circumferential surface of the tilt suppression portion 333 in the 1 o'clock, 3 o'clock, 5 o'clock, 7 o'clock, 9 o'clock, and 11 o'clock directions. Therefore, the fixed portion of the rib 351 relative to the plate member 421 does not overlap with the fixed portion of the rib 361 relative to the plate member 421 in the axial direction of the scraping roller unit 131.

The scraping roller unit 132 has a structure that is symmetrical to the scraping roller unit 131. The description of the scraping roller unit 131 is applicable to the scraping roller unit 132, taking symmetry into consideration.

When the scraping roller units 131 and 132 are attached to the housing 120, the scraping rollers 310 of the scraping roller units 131 and 132 are disposed in the suction space 110. At this time, a gap is formed between the tips (tip caps 313) of the scraping roller units 131 and 132. A flow path 241 opens in the front wall portion 240 of the rear portion 125 at a position overlapping this gap in the front-to-rear direction.

How the scraping roller unit 131 is held by the side portion 123 will be described with reference to FIG. 14. FIG. 14 is a schematic longitudinal cross-sectional view of the suction tool 100 around the side portion 123.

Within the side portion 123, a drive space 341 (a space surrounded by the front wall portion 171, the left outer wall portion 126, the lower wall portion 127, and the inner wall portion 172) is formed in which the pulley 340 of the scraping roller unit 131 is housed. In addition, on the scraping roller 310 side of the drive space 341 (i.e., a position adjacent to the suction space 110 in the width direction), a storage portion 342 in which the main part 331 of the scraping roller unit 131 is housed is formed in the side portion 123. By housing the main part 331 of the scraping roller unit 131 in the storage portion 342, the scraping roller unit 131 is cantilever-supported by the housing 120.

The storage section 342 is formed by the inner wall section 172 and the bottom wall section 127 of the housing 120. The inner wall section 172 has a shape complementary to the main section 331 of the scraping roller unit 131 and has a storage space 343 that opens downward and is recessed from the suction space 110 side. The downward opening of the storage space 343 is closed by the bottom wall section 127.

In the following description, the portion of the inner wall 172 that follows the outer peripheral surface of the main portion 331 is referred to as the "circumferential wall 344." The peripheral wall 344 is a portion that forms the outer peripheral surface 185 (see FIG. 2) of the inner wall 172. In the following description, the portion of the inner wall 172 that stands so as to separate the storage space 343 and the drive space 341 is referred to as the "partition wall 345."

The inner surface of the peripheral wall portion 344 (i.e., the surface opposite to the outer peripheral surface 185) is configured to contact the outer peripheral surface of the main portion 331. An engagement portion 347 that engages with the upper protrusion 423 of the main portion 331 in the width direction of the suction tool 100 is provided at the tip of the inner peripheral surface of the peripheral wall portion 344 (i.e., the end portion on the suction space 110 side). In detail, the engagement portion 347 protrudes downward from the inner surface of the peripheral wall portion 344 on the suction space 110 side relative to the protrusion 423 and abuts against the side of the protrusion 423.

The inner wall portion 172 has a through hole penetrating the partition wall 345 in the axial direction of the scraping roller unit 131. This through hole has a large diameter at a position corresponding to the second reinforcement portion 360, and a small diameter on the base end side (i.e., the pulley 340 side) relative to the second reinforcement portion 360. The second reinforcement portion 360 of the scraping roller unit 131 is accommodated in the part of the through hole having the large diameter, and the part of the tilt suppression portion 333 protruding toward the pulley 340 side relative to the second reinforcement portion 360 is inserted into the part of the through hole having the small diameter. The inner peripheral portion of the partition wall 345 abuts against the outer peripheral surface of the part of the tilt suppression portion 333 protruding toward the pulley 340 side relative to the second reinforcement portion 360.

The inner surface of the partition wall 345 (i.e., the surface facing the storage space 343) contacts the base end surface 429 of the main part 331 when the main part 331 is stored in the storage space 343. Therefore, the upper part of the main part 331 is sandwiched in the width direction of the suction tool 100 between the engaging part 347 on the inner surface of the peripheral wall part 344 that engages with the protruding part 423 and the inner surface of the partition wall 345.

The lower end portion of the protruding portion 424 of the main portion 331 is aligned with the bottom wall portion 127 in the width direction of the suction tool 100 when the main portion 331 is accommodated in the accommodation portion 342. That is, the lower end portion of the protruding portion 424 is located on the suction space 110 side of the bottom wall portion 127 and is in contact with the edge of the bottom wall portion 127 on the suction space 110 side. On the side of the protruding portion 424 opposite the bottom wall portion 127, the suction space 110 opens downward.

When the main part 331 is accommodated in the accommodation part 342, the screw hole 427 of the main part 331 is connected to the lower end of the screw hole 187 of the inner wall part 172. The screw 346 is screwed into these screw holes 187, 427. When the screw 346 is screwed, even if the accommodation space 343 is larger than the main part 331, the main part 331 is lifted upward by the screw 346, and the upper part of the outer circumferential surface of the main part 331 is pressed against the inner surface of the peripheral wall part 344. In other words, the screw 346 functions as a pressing part that presses the outer circumferential surface of the main part 331 against the inner surface of the peripheral wall part 344.

The operation of the suction tool 100 and the cleaning machine 101 is described below.

When the operating unit 104 is operated, the cleaner 101 is activated and suction force acts on the suction space 110 through the hose 103 and the flow path 241 formed in the rear part 125 of the suction tool 100. As a result, dust on the floor surface flows into the suction space 110 through the downward opening of the suction space 110. The dust is then collected in the cleaner 101 through the flow path 241 and the hose 103.

During this time, the motor 151 built into the suction tool 100 operates, and the driving force of the motor 151 is transmitted to the rotating shaft 320 of the scraping roller unit 131 via the drive belt 153. The tip of the rotating shaft 320 is connected to the scraping roller 310 inside the scraping roller 310, so that the scraping roller 310 rotates together with the rotating shaft 320.

At this time, the brush portion 312 provided on the outer circumferential surface 316 of the tube portion 311 of the scraping roller 310 comes into contact with the floor surface, scrapes off dust on the floor surface, and sends it rearward. Because a flow path 241 is formed behind the brush portion 312, a relatively strong suction force is acting on the rear side of the scraping roller 310. Therefore, the dust sent rearward by the brush portion 312 is subjected to a relatively strong suction action and is sucked into the cleaner 101.

While the scraping roller 310 rotates once, any part of the six brush parts 312 is in contact with the floor surface, and the scraping roller 310 is not separated from the floor surface. This prevents the load that the scraping roller 310 receives from the floor surface (i.e., the load on the motor 151) from suddenly decreasing, thereby suppressing vibration of the scraping roller 310 and noise from the scraping roller 310.

When the scraping roller 310 is scraping off dust on the floor surface, long dust particles (e.g., hair) may wrap around the scraping roller 310 (see FIG. 15). Because the scraping roller 310 has a tapered shape that narrows toward the tip, the component force of the wrapping force of the long dust particles tends to be directed toward the tip of the scraping roller 310. Therefore, the long dust particles wrapped around the scraping roller 310 can be moved toward the tip of the scraping roller 310.

In addition, the lead angle of the brush portion 312 is smaller at the base end side of the scraping roller 310, so dust captured by the scraping roller 310 at the base end side is sent with a large force to the tip side. The lead angle of the brush portion 312 gradually increases from the base end side to the tip side (see Figure 9), so the length of the brush portion 312 (and therefore the distance traveled by dust moving along the brush portion 312) becomes shorter. Therefore, the dust can reach the tip of the scraping roller 310 in a short period of time.

In order to prevent long dust from biting into brush portion 312, the arrangement density of brush bristles in brush portion 312 is set to 130 bristles/ ^mm2 or more. When the arrangement density of brush bristles of a general thickness used to scrape off dust is set to 130 bristles/ ^mm2 or more, the distance between adjacent brush bristles becomes equal to or less than the diameter of a relatively thin hair (approximately 0.04 μm), making it difficult for the hair to get into brush portion 312. Since long dust is difficult to bite into brush portion 312, the long dust captured by brush portion 312 can move to the tip side of scraping roller 310.

The left and right scraping roller units 131, 132 are supported at one end so that a gap is formed between the tips of the scraping rollers 310. A flow path 241 is formed behind the gap between the tips of the scraping rollers 310. Therefore, long dust particles that reach the tips of the scraping rollers 310 are subjected to suction force from the flow path 241 and are sucked into the flow path 241 through the gap between the tips of the scraping rollers 310.

When a long rotating body (in this embodiment, the scraping roller units 131, 132) is supported at one end, the tilting of the rotating body, the stress on the support part caused by the tilting, and the axial vibration of the rotating body tend to be greater than in a double-supported structure. The scraping roller units 131, 132 and the housing 120 are designed to eliminate these problems.

The scraping roller units 131, 132 may tilt if the scraping roller 310 runs over an object on the floor. Alternatively, the scraping roller units 131, 132 may tilt if a foreign object gets caught between the scraping roller 310 and the wall portion around the scraping roller 310 (i.e., the front wall portion 240 of the rear portion 125 and the cover member 122). In these cases, an external force acts to tilt the axis of the scraping roller 310 (in FIG. 14, an upward external force is indicated by arrow A1, and a downward external force is indicated by arrow A2).

When the above-mentioned external force acts on the scraping roller 310, a force acts to press the outer surface of the main part 331 of the bearing unit 330 against the storage part 342. In this embodiment, the main part 331 is configured to distribute the force pressing the outer surface of the main part 331 against the storage part 342. That is, the outer diameter of the main part 331 is larger than the outer diameter of the base end part 314 of the tube part 311, which is the largest among the outer diameters of the outer peripheral surface 316 of the tube part 311 of the scraping roller 310. Therefore, the contact area of the main part 331 with the storage part 342 is larger than that of a structure in which the scraping roller 310 is supported by a bearing smaller than the outer diameter of the scraping roller 310. As a result, the force pressing the outer surface of the main part 331 against the storage part 342 can be distributed and applied to the main part 331.

The bearing unit 330 is configured so that not only the outer circumferential surface of the main part 331 but also the outer circumferential surface of the tilt suppression part 333 contacts the accommodation part 342. That is, the outer circumferential surface of the main part 331 contacts the inner surface of the peripheral wall part 344, and the outer circumferential surface of the tilt suppression part 333 contacts the inner circumferential surface of the partition wall 345 at a position spaced from the main part 331 toward the pulley 340. These contact parts are located at positions spaced from each other in the axial direction of the scraping roller unit 131. The scraping roller unit 131 is held by the housing 120 at two positions spaced from each other in the axial direction, so that tilting of the scraping roller unit 131 is suppressed.

When an upward external force (arrow A1 in FIG. 14) acts on the scraping roller 310, a force (arrow A3 in FIG. 14) acts on the upper part of the main part 331 (i.e., the part above the rotating shaft 320) in the opposite direction to the suction space 110. On the other hand, a force (arrow A4 in FIG. 14) acts on the lower part of the main part 331 (i.e., the part below the rotating shaft 320) in the direction toward the suction space 110.

At this time, the partition wall 345 resists the force (arrow A3) in the opposite direction to the suction space 110, preventing the upper part of the main portion 331 from moving in the opposite direction to the suction space 110.

The force (arrow A4) acting on the lower part of the main part 331 may tilt or deform so that the protrusion 424 at the lower end of the main part 331 is displaced in a direction away from the bottom wall part 127, but such tilt or deformation is permitted to a certain extent. That is, the suction space 110 is open on the side of the protrusion 424 opposite the bottom wall part 127, and the protrusion 424 is not restrained on the suction space 110 side. Therefore, the stress generated in the main part 331 is reduced, and the load on the bearing unit 330 is reduced.

When a downward external force (arrow A2 in FIG. 14) acts on the scraping roller 310, a force (arrow A5 in FIG. 14) acts on the upper part of the main part 331 in the direction toward the suction space 110. On the other hand, a force (arrow A6 in FIG. 14) acts on the lower part of the main part 331 (i.e., the part below the rotating shaft 320) in the direction opposite to the suction space 110.

The force acting on the upper part of the main part 331 (arrow A5) is received by the engagement part 347 that engages with the upper protrusion 423 of the main part 331 on the suction space 110 side. The force acting on the lower part of the main part 331 (arrow A6) is received not only by the partition wall 345, but also by the edge of the lower wall part 127 that is in contact with the lower protrusion 424. In this way, the storage part 342 of the housing 120 can receive the force acting on the main part 331 in a distributed manner at different positions, reducing the load on the housing 120.

The axial vibration of the rotating shaft 320 is suppressed by the axial vibration prevention part 370. The tip tube part 332 of the axial vibration prevention part 370 is formed integrally with the main part 331, so it can resist the axial vibration of the rotating shaft 320 together with the main part 331. In addition, since the tip tube part 332 protrudes more from the main part 331 than the tilt suppression part 333, the rotating shaft 320 can be held at a position away from the bearing 380, and the axial vibration suppression effect can be obtained over a long section of the rotating shaft 320. In order to obtain the axial vibration suppression effect over a long section of the rotating shaft 320, the tip tube part 332 of the axial vibration prevention part 370 protrudes relatively far from the main part 331, but since the tip tube part 332 is inserted into the scraping roller 310, the scraping roller unit 131 does not become excessively long.

Since the rotating shaft 320 is connected to the scraping roller 310 and the axial vibration prevention part 370, an external force applied to the scraping roller 310 is transmitted to the axial vibration prevention part 370 through the rotating shaft 320. Since the first reinforcing part 350 is connected to the outer peripheral surface of the axial vibration prevention part 370 and the tip surface 428 of the main part 331, the external force transmitted to the axial vibration prevention part 370 is transmitted to the tip surface 428 through the first reinforcing part 350. Therefore, the external force is not concentrated at the base of the axial vibration prevention part 370, but is also dispersed to the connection part between the first reinforcing part 350 and the tip surface 428 of the main part 331.

For example, when an upward external force (arrow A1 in FIG. 14) is applied to the scraping roller 310, the tilt suppression part 333 is pressed downward against the inner peripheral surface of the partition wall 345 and receives an upward reaction force from the inner peripheral surface of the partition wall 345. This reaction force is not concentrated at the base of the tilt suppression part 333, but is also dispersed to the connection part between the second reinforcement part 360 and the base end surface 429 of the main part 331 due to the second reinforcement part 360 connected to the outer peripheral surface of the tilt suppression part 333 and the base end surface 429 of the main part 331.

When an upward external force (arrow A1 in FIG. 14) is applied to the scraping roller 310, a force acts on the ribs 351, 361 on the upper side of the rotating shaft 320 to compress the plate member 421 of the main part 331 in the axial direction. On the other hand, a force acts on the ribs 351, 361 on the lower side of the rotating shaft 320 in a direction to peel them off from the plate member 421 of the main part 331. Because the connection positions of the ribs 351, 361 to the main part 331 do not overlap in the axial direction, the force that the main part 331 receives from the ribs 351, 361 is not concentrated in one place. Therefore, the load on the main part 331 is reduced.

When an external force (for example, arrows A1 and A2 in FIG. 14) acts on the tip or base end of the scraping roller 310, this external force acts as a moment on the fixed part 411 that fixes the scraping roller 310 to the rotating shaft 320. Since the fixed part 411 is connected to the rotating shaft 320 closer to the midpoint in the axial direction of the scraping roller 310 than the tip and base ends of the scraping roller 310, the moment acting on the fixed part 411 does not become excessively large.

In addition, the tip cap 334 of the axial vibration prevention unit 370 holds the rotating shaft at a position adjacent to the fixed unit 411, so the tip cap 334 is also connected to the rotating shaft 320 near the midpoint in the axial direction of the scraping roller 310. Therefore, the moment acting on the tip cap 334 does not become excessively large.

Because the bearing unit 330 and the housing 120 are made of resin, they can be manufactured based on resin molding technology. In this case, a gap may occur between the main part 331 and the accommodating part 342 of the bearing unit 330 due to molding errors. If the main part 331 repeatedly comes into contact with and separates from the accommodating part 342, noise may be generated from the suction tool 100. To prevent such noise, a connection structure is adopted in which the main part 331 and the accommodating part 342 are connected by a screw 346.

When a gap is generated between the main part 331 and the housing part 342 of the bearing unit 330, when the screw 346 is screwed into the screw hole 187, 427, the main part 331 moves upward within the housing part 342. As a result, the upper part of the outer peripheral surface of the main part 331 remains in contact with the housing part 342, while the lower part of the outer peripheral surface of the main part 331 remains spaced apart from the housing part 342. In other words, because the main part 331 does not come into contact with or separate from the housing part 342, noise from the suction tool 100 is suppressed.

To suppress noise from the suction tool 100, as shown in FIG. 16, the contact portion of the housing portion 342 with the main portion 331 may be lined with a compressible cushion member 188 (e.g., felt cloth). In this case, since the cushion member 188 is interposed between the main portion 331 and the housing portion 342, the main portion 331 does not come into direct contact with the housing portion 342, and noise is suppressed. In addition, since the cushion member 188 is compressible and deformable, it can reduce the force acting from the main portion 331 to the housing portion 342 and the force acting from the housing portion 342 to the main portion 331, thereby protecting the main portion 331 and the housing portion 342.

The tubular portion 311 and the fixed portion 411 of the scraping roller 310 are also molded from resin. In this case, the scraping roller 310 has a higher strength than a structure in which the tubular portion 311 and the fixed portion 411 are configured as separate parts. In addition, since the fixed portion 411 is integrated with the rotating shaft 320 during the molding process of the scraping roller 310, the connection strength between the fixed portion 411 and the rotating shaft 320 can be increased.

In the above embodiment, the rear end portion of the main portion 331 (i.e., the portion of the plate member 421 that protrudes rearward from the outer fitting ring 422) is thinner than the front end portion of the main portion 331. The storage portion 342 is formed to be complementary to the shape of the main portion 331. Therefore, even if the user attempts to attach the scraping roller unit 131 to the side portion 123 by reversing the front and rear of the main portion 331, the main portion 331 will not be stored in the storage portion 342. In other words, the user is prevented from attaching the scraping roller unit 131 to the side portion 123 in the wrong orientation.

In the above embodiment, the bearing 380 holds the rotating shaft 320 by the base end cap 335 disposed adjacent to the pulley 340. The pulley 340 receives an external force in the radial direction of the scraping roller 310 due to the tension of the drive belts 153 and 154. This external force acts as a moment (load on the base end cap 335) on the base end cap 335. This moment is not excessively large because the base end cap 335 is disposed adjacent to the pulley 340.

In the above embodiment, the scraping roller 310 has a tapered shape that narrows toward the tip. Alternatively, the outer circumferential surface 316 of the tube portion 311 of the scraping roller 310 may have a substantially constant outer diameter. In this case, the dust removal function due to the tapered shape of the scraping roller 310 is lost, but this dust removal function may be supplemented by other structures. For example, an inclined protrusion may be provided so as to contact the brush portion 312 of the scraping roller 310 so as to move the dust toward the tip of the scraping roller 310. When the dust wrapped around the scraping roller 310 reaches the tip of the scraping roller 310, it receives a suction force from the flow path 241 and is sucked into the flow path 241 through the gap between the left and right scraping rollers 310.

In the above-described embodiment, in order to reduce the rotational resistance to the rotating shaft 320, the bearing unit 330 is spaced from the outer circumferential surface of the rotating shaft 320 in the axial length section between the tip cap 334 and the base cap 335 at both ends of the bearing unit 330. Alternatively, as shown in FIG. 17, in order to reduce the number of parts, the inner diameter of the bearing unit 330 may be made approximately equal to the diameter of the rotating shaft 320, and the tip cap 334 and the base cap 335 may be omitted. In this case, the bearing 380 can be formed only from the main portion 331, and the axial vibration prevention portion 370 can be formed only from the tip tube portion 332.

In the above embodiment, the outer periphery of the scraping roller 310 is composed of six brush parts 312. The number of brush parts 312 to be used for the outer periphery of the scraping roller 310 may be determined in consideration of the load on the motor 151 and the amount of dust wrapped around the scraping roller 310 that is embedded in the brush parts 312. In detail, the more brush parts 312 that constitute the outer periphery of the scraping roller 310, the higher the load on the motor 151. On the other hand, if there are more brush parts 312, the winding force of long dust acting on each brush part 312 is smaller, and the amount of long dust that is embedded in the brush parts 312 is smaller. In addition, if five or more brush parts 312 are provided at equal intervals in the circumferential direction, the winding angle of dust at the tip of each brush part 312 becomes obtuse (120° in the case of six brush parts 312), and from this viewpoint, the embedding of long dust into the brush parts 312 is also suppressed.

The principle of this embodiment is ideally suited for use in equipment used for cleaning work.

100... Suction tool 110... Suction space 120... Housing 131, 132... Scraping roller unit 188... Cushion member 310... Scraping roller 311... Cylinder portion 312... Brush portion 314... Base end portion 320... Rotating shaft 333... Tilt suppression portion 340... Pulley 342... Storage portion 346... Screw (pressing portion)
350: First reinforcing portion 360: Second reinforcing portion 370: Shaft vibration prevention portion 380: Bearing 411: Fixed portion 424: Protruding portion 428: Tip surface

Claims (15)

A scraping roller unit configured to be cantilever-supported by a housing that defines a suction space that opens downward,
A rotating shaft;
A scraping roller fixed to the rotating shaft;
A bearing through which the rotating shaft is inserted;
a tilt suppressing portion that is fitted onto the rotating shaft on the opposite side of the bearing from the scraping roller,
The outer diameter of the bearing is larger than the diameter of the outer circumferential surface of the scraping roller,
the bearing is configured to be held by the housing with an outer circumferential surface of the bearing in contact with the housing when the scraping roller unit is attached to the housing,
The tilt suppression portion is formed so that, when the scraping roller unit is attached to the housing, the outer peripheral surface of the tilt suppression portion is held in the housing at a position spaced apart from the bearing. A scraping roller unit configured to be cantilever-supported by a housing that defines a suction space that opens downward,
A rotating shaft;
A scraping roller fixed to the rotating shaft;
a bearing through which the rotating shaft is inserted;
The outer diameter of the bearing is larger than the diameter of the outer circumferential surface of the scraping roller,
the bearing is configured to be held by the housing with an outer circumferential surface of the bearing in contact with the housing when the scraping roller unit is attached to the housing,
The scraping roller has a base end that opens toward the bearing,
The rotating shaft is inserted into the scraping roller through an opening at the base end of the scraping roller,
The scraping roller unit further includes an anti-axial vibration portion fixed to a tip end surface of the bearing facing the base end portion of the scraping roller,
The scraping roller is fixed to the rotating shaft at a position closer to a middle position in an axial direction of the scraping roller than a base end and a tip end of the scraping roller,
The axial vibration prevention portion protrudes from the tip surface into the scraping roller, and is fitted onto the rotating shaft at a position within the scraping roller closer to the tip than the base end of the rotating shaft, thereby preventing axial vibration of the rotating shaft , and is configured to hold the rotating shaft at a position adjacent to a fixed portion of the scraping roller relative to the rotating shaft . A scraping roller unit configured to be cantilever-supported by a housing that defines a suction space that opens downward,
A rotating shaft;
A scraping roller fixed to the rotating shaft;
a bearing through which the rotating shaft is inserted;
The outer diameter of the bearing is larger than the diameter of the outer circumferential surface of the scraping roller,
the bearing is configured to be held by the housing with an outer circumferential surface of the bearing in contact with the housing when the scraping roller unit is attached to the housing,
The scraping roller has a base end that opens toward the bearing,
The rotating shaft is inserted into the scraping roller through an opening at the base end of the scraping roller,
The scraping roller unit includes:
an anti-axial vibration portion fixed to a tip surface of the bearing facing the base end portion of the scraping roller;
a tilt suppressing portion that is fitted onto the rotating shaft on the opposite side of the bearing from the scraping roller, and that suppresses tilting of the rotating shaft by being held by the housing at a position where an outer circumferential surface is separated from the bearing when the scraping roller unit is attached to the housing;
a first reinforcing part fixed to the tip end surface of the bearing so that an external force applied to the axial vibration prevention part is received by the tip end surface of the bearing;
a second reinforcing portion fixed to the base end surface so that an external force applied to the tilt suppression portion is received by the bearing at the base end surface opposite to the tip end surface,
the axial vibration prevention portion protrudes from the tip surface into the scraping roller, and is fitted onto the rotating shaft at a position within the scraping roller closer to the tip than to the base end of the rotating shaft, thereby preventing axial vibration of the rotating shaft;
A scraping roller unit, wherein the first reinforcement portion and the second reinforcement portion are arranged at a position where a fixed portion of the first reinforcement portion relative to the tip end surface does not overlap a fixed portion of the second reinforcement portion relative to the base end surface in the axial direction of the scraping roller unit. The scraping roller includes a plurality of band-shaped brush portions that configure an outer periphery of the scraping roller so as to scrape off dust on a floor surface,
The scraping roller unit according to any one of claims 1 to 3, wherein the plurality of brush portions are spaced apart in the circumferential direction of the scraping roller, and each of the brush portions extends spirally in the axial direction of the scraping roller so that any portion of the plurality of brush portions continues to contact the floor surface during one rotation of the scraping roller. the scraping roller includes a band-shaped brush portion that configures an outer periphery of the scraping roller so as to scrape off dust on a floor surface,
The scraping roller unit according to claim 1 , wherein the brush portion extends in a spiral shape such that a lead angle gradually increases from a base end side to a tip end side of the scraping roller. the scraping roller includes a brush portion that configures an outer periphery of the scraping roller so as to scrape off dust on a floor surface,
The scraping roller unit according to claim 1 , wherein the brush portion includes a plurality of brush bristles arranged at a density of 130 bristles/mm ² or more in the region where the brush portion is provided. A pulley is attached to the rotating shaft proximal to the bearing,
7. A scraper roller unit according to claim 1, wherein the bearing is configured to hold the rotatable shaft adjacent the pulley. A scraping roller unit configured to be cantilever-supported by a housing that defines a suction space that opens downward,
A rotating shaft;
A scraping roller fixed to the rotating shaft;
a bearing through which the rotating shaft is inserted;
The outer diameter of the bearing is larger than the diameter of the outer circumferential surface of the scraping roller,
the bearing is configured to be held by the housing with an outer circumferential surface of the bearing in contact with the housing when the scraping roller unit is attached to the housing,
The scraping roller is fixed to the rotating shaft at a position closer to a middle position in an axial direction of the scraping roller than a base end and a tip end of the scraping roller. The scraping roller includes a cylindrical portion into which the rotating shaft is inserted, a brush portion attached to an outer periphery of the cylindrical portion so as to scrape off dust, and a fixed portion configured to be fixed to the rotating shaft within the cylindrical portion,
The scraping roller unit according to claim 1 , wherein the cylindrical portion and the fixed portion are integrally formed. The scraping roller unit according to claim 9 , wherein the fixed portion is fixed to the rotating shaft by injecting a resin around the rotating shaft. a housing defining a suction space that is open downward;
The scraping roller unit according to any one of claims 1 to 10 ,
The scraping roller is disposed in the suction space,
the housing includes a receiving portion that is recessed so as to support the bearing of the scraping roller unit at a position adjacent to the suction space in a width direction of the housing,
The suction tool is configured so that the accommodating portion abuts against the upper part of the bearing, which is the part above the rotating shaft, on the suction space side and on the opposite side to the suction space, and abuts against the lower part of the bearing, which is the part below the rotating shaft, on the opposite side to the suction space, while not abutting on the suction space side. the scraping roller unit includes a downward protrusion protruding from the outer circumferential surface of the bearing,
The suction tool according to claim 11 , wherein the accommodating portion is configured to abut against the bearing and the protrusion on a side opposite to the suction space with respect to the bearing and the protrusion. The protrusion protrudes downward from the outer circumferential surface of the lower portion of the bearing,
The suction tool according to claim 12 , wherein the accommodating portion is configured to abut against the lower portion and the protruding portion of the bearing on a side opposite to the suction space. The suction tool according to claim 1 1 to 13 , further comprising a pressing portion for pressing the bearing against the housing portion. The suction tool according to claim 11 , further comprising a cushion member interposed between the bearing and the housing portion.

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