CN111818874A - electric toothbrush - Google Patents

Abstract

A toothbrush attachment (100) for detachable attachment to a motor drive unit of an electric toothbrush, wherein the toothbrush attachment (100) includes: a main housing (110) including a longitudinal axis (X-X') a tubular neck portion (213) and a head portion (215) defining a toothbrush receiving portion (216); a toothbrush head (200) rotatably mounted on the toothbrush receiving portion (216) of the head portion (215) and rotatably on the brush axis (Z‑Z'); and a drive linkage (280) mounted within the neck portion (213) and having an axis of rotation (Y‑Y'); the drive linkage (280) including a crankshaft (230 ), the bushing device (240) and the coupling shaft part; the coupling shaft part includes an engagement device at the axial free end, and the crankshaft (230) drives the toothbrush head (200) to rotate reciprocally around the brush axis (Z‑Z') , and the coupling shaft part and the crankshaft (230) are integrally formed as an integral component and the crankshaft (230) is rotatably mounted on the bushing device (240).

Description

electric toothbrush

technical field

The disclosure of the present invention relates to the field of oral care devices, in particular to electric toothbrushes. More specifically, the present disclosure relates to brush heads for electric toothbrushes.

Background technique

Electric toothbrushes offer a convenient, useful and effective alternative to manual toothbrushes. A typical modern electric toothbrush includes a motor-driven base unit and a toothbrush accessory that is removably attached to the base unit. Toothbrush attachments typically include a toothbrush head having a forward-facing surface that will engage the user's teeth for brushing and rotate or vibrate on the teeth to aid in tooth cleaning. A detachable toothbrush attachment is advantageous and facilitates periodic replacement of the brush head at a reasonable cost at regular intervals. A motorized drive unit, commonly referred to as a drive unit or handpiece, typically includes a motor and a motor-driven drive shaft that drives the toothbrush head for cleaning rotation. The cleaning rotation is generally a reciprocating rotation about the axis of rotation between a first angle of rotation and a second angle of rotation.

SUMMARY OF THE INVENTION

The present invention discloses a toothbrush attachment for removably attaching to a motor drive unit of an electric toothbrush. The motor drive unit includes a motor and a motor driven drive shaft that will reciprocately rotate about the axis of rotation of the drive shaft. The toothbrush attachment includes: a main housing including a tubular neck portion having a longitudinal axis and a head portion defining a toothbrush receiving portion; a toothbrush head rotatably mounted to the toothbrush receiving portion of the head portion and a rotatable brush axis and a drive coupling mechanism mounted inside the neck portion and having an axis of rotation. The drive coupling mechanism includes a crankshaft, a bushing arrangement and a coupling shaft portion. The coupling shaft portion comprises at the axial free end engagement means adapted for releasable coupling driving engagement with the drive shaft of the motor drive unit to receive rotational drive power from the drive shaft and to drive the received rotational drive Power is transmitted to the crankshaft. The crankshaft is used to drive the toothbrush head in reciprocating rotation about the brush axis, and wherein the coupling shaft portion and the crankshaft are integrally formed as a unitary member and the crankshaft is rotatably mounted on the bushing arrangement.

Description of drawings

The present disclosure will be described by way of example and with reference to the accompanying drawings, wherein:

1 is a perspective view of an exemplary toothbrush attachment according to the present disclosure,

Figure 1A is a perspective view of the exemplary toothbrush attachment of Figure 1 with a portion cut away,

FIG. 1B is a perspective view of the exemplary toothbrush attachment of FIG. 1 without the tubular housing,

Figure 2 is an exploded view of the exemplary toothbrush attachment of Figure 1,

Figure 3 is a perspective view of the brush assembly in the exemplary toothbrush accessory of Figure 1,

Figure 4 is a perspective view of the semi-assembled toothbrush attachment of Figure 1,

5 is a cross-sectional view of the exemplary toothbrush accessory of FIG. 1 engaged with the drive output of the exemplary electric toothbrush drive unit,

FIG. 6 is a perspective view of an exemplary toothbrush accessory 200,

Figure 6A is an exploded view of the toothbrush attachment 200,

6B1 is a perspective view of the drive coupling assembly of the toothbrush attachment 200,

Figure 6B2 is a longitudinal cross-sectional view of the drive coupling assembly of Figure 6B1 taken along the fin portion,

Figures 7A and 7B are plan and side views of the toothbrush attachment of Figure 6 with the toothbrush head removed,

Fig. 7A1 is a longitudinal cross-sectional view of the toothbrush attachment of Fig. 7A as viewed from direction A of Fig. 7A,

Figures 7A2 and 7A3 are longitudinal cross-sectional views taken along line E-E' of Figure 7B and viewed from directions B and C, respectively,

8A and 8B are perspective and side views of another exemplary drive coupling assembly,

Fig. 8C is a cross-sectional view taken along the line F-F' of Fig. 8B and viewed in the direction of the arrow,

Fig. 8D is a cross-sectional view taken along the line G-G' of Fig. 8B and viewed in the direction of the arrow, and

9A and 9B are views of the bushing assembly of FIG. 8A assembled and semi-assembled to the crank member of the drive coupling assembly.

Detailed ways

As shown in FIG. 1, the exemplary toothbrush 100 includes a tubular housing 110 having a first longitudinal end 112 and a second longitudinal end 114, a brush assembly 120 mounted at the second longitudinal end of the tubular housing, and a mounting A drive mechanism 180 extends inside the tubular housing and between the first and second longitudinal ends of the tubular housing. As shown in Figures 1A and 1B, an exemplary toothbrush 100 is a toothbrush accessory suitable for use with an electric toothbrush drive unit ("drive handle") having a drive output. In preparation for brushing, the toothbrush attachment is inserted into the axial end of the electric toothbrush drive unit such that the drive mechanism is mechanically coupled to the free axial end of the power take-off shaft 510 of the drive handle so that the rotational or oscillatory motion of the motor output shaft is prevented by Coupled to drive mechanism 180 and brush assembly 120 .

The tubular housing 110 is rigid and elongated and extends along the longitudinal axis X-X'. The tubular housing optionally has a generally circular cross-section and defines a generally circular aperture along a major portion of its length. The tubular housing 110 has a first longitudinal end 112 ("handle coupling end") for coupling engagement with a power toothbrush driver, and a second longitudinal end 114 ("bristle carrier end") to which the brush assembly 120 is attached. department"). The hole defined by the hollow housing 110 defines a tapered through passage to form a through passage for the drive mechanism for driving the bristle carrier. The cross-sectional dimension of the tubular housing 110 and the through passages defined therein progressively decreases as it extends from the handle coupling end 112 to the bristle carrier end 114 .

The brush holder 116 is integrally formed onto the tubular housing 110 as an integral extension and extends axially away from the second longitudinal end 114 of the tubular housing 110 . The brush holder 116 includes a housing that defines a brush receiver having a receiver axis. In exemplary embodiments, such as in this embodiment, the receptacle axis is substantially orthogonal to the longitudinal axis of the housing. In an exemplary embodiment, an extension of the longitudinal axis X-X' of the tubular housing projects into the receptacle and intersects the receptacle axis. The brush holder 116 includes a main peripheral wall that defines a receiver compartment and an access aperture to the receiver compartment. The peripheral wall includes an inlet portion extending about the brush receiver axis to define a generally circular inlet portion. The inlet portion is a collar portion having a collar wall defining an inlet end. The inlet end of the collar portion is the free end that defines the top surface of the brush receiving portion. The receiver axis is also the central axis of the brush receiver, which is coaxial with the toothbrush axis Y-Y'. The toothbrush axis Y-Y' intersects the longitudinal axis X-X' and is orthogonal to the longitudinal axis X-X' in an exemplary embodiment as in this embodiment. The brush assembly 120 is mounted on the brush receiver and is rotatable relative to the brush receiver about the toothbrush axis Y-Y'.

The first longitudinal end 112 of the tubular housing 110 is the handle coupling end of the toothbrush attachment 100 and includes a coupling neck. The coupling neck has an end surface at its longitudinal free end. The end surface defines a coupling plane and a coupling surface extending substantially parallel to the toothbrush axis Y-Y' or substantially orthogonal to the longitudinal axis X-X'. The coupling surface will face the drive handle and be in abutting contact with the drive handle during use. The coupling neck defines an entry hole through which the drive shaft 510 of the drive handle enters the tubular housing 110 for mechanical engagement with the drive mechanism.

Referring to FIGS. 2 and 3 , the brush assembly 120 includes a bristle carrier 122 and a plurality of cleaning elements 125 mounted on the bristle carrier 122 . The bristle carrier 122 includes a bristle disc 124 and a coupling portion formed on one surface of the bristle disc 124 that is received inside the brush receiving portion and that is not mounted with a cleaning element. Bristle disks are also referred to as filament disks, wherein the cleaning elements include tufts of bristle filaments. A plurality of cleaning elements 125 are mounted on the other free surface of the bristle disk 124 opposite the surface carrying the drive head. The cleaning elements 125 include tufts of bristles that extend, distribute and mount in a direction substantially parallel to the toothbrush axis Y-Y'. In some embodiments, the bristle tufts extend at different angles and/or inclinations and/or orientations relative to the axis of rotation of the brush assembly. The bristle disk 124 is generally circular and is also known commercially as a filament disk. The coupling portion is a base portion 126 integrally formed on one surface of the bristle disk 124 opposite to the surface carrying the bristles 125 . The filament tray includes a top or first surface on which cleaning elements are mounted, a bottom or second surface on which the drive head is formed, and a peripheral wall interconnecting the first and second surfaces. The collar portion of the brush holder surrounds the peripheral wall of the filament disk. In exemplary embodiments, such as in this embodiment, the top surface of the filament tray and the top surface of the receptacle are substantially parallel and/or flush.

Brush assembly 120 is rotatably mounted on toothbrush holder 116 and is rotatable about a brush axis formed by connecting pin 127 . The connecting pin 127 has a pin axis that is aligned (i.e., coaxial) with the toothbrush axis Y-Y' to define the axis of the brush assembly 120. A pin holder having a pin receiver and a pin holder axis is formed in the bottom surface of the brush receiver to receive the pin 127 . The pin receiver has a pin receiver axis that is coaxial with or defines the toothbrush axis Y-Y'. In exemplary embodiments, such as in this embodiment, the pin holder axis is substantially coaxial with the receiver axis, such that the brush assembly 120 is disposed substantially centrally relative to the brush receiver.

The base portion 126 is formed with a guide groove 128 extending in a direction parallel to the toothbrush axis Y-Y'. A guide slot 128 is formed on the side of the brush assembly 120 proximal of the joint formed by the intersection of the second longitudinal end 114 and the brush holder 116 . The guide slot 128 defines a rearwardly facing drive track that faces the inlet aperture of the tubular housing 110 and is drivingly engaged with the drive member 130 .

The base portion 126 is formed with a guide groove 129 extending in a direction orthogonal to the toothbrush axis Y-Y'. A guide slot 129 is formed on the side of the brush assembly 120 that is distal to and facing away from the joint formed by the intersection of the second longitudinal end 114 with the brush holder 116 . The guide pin 117 extends from the brush holder 116 and protrudes into the guide groove 129 . The guide slot 129 defines a forward-facing guide track that extends in a direction substantially orthogonal to the axis of rotation of the brush assembly 120 . Guide slot 129 and guide pin 117 cooperate to form a guide assembly that acts as an auxiliary guide to reduce tilting of brush assembly 120 to maintain rotation of brush assembly 120 about toothbrush axis Y-Y' during operation. The guide track also acts as a limiting means to limit the maximum angle or extent of rotation about the toothbrush axis Y-Y' during operation.

In an exemplary embodiment, such as in this embodiment, as shown in FIGS. 1A and 1B , drive mechanism 180 includes crank member 130 , bushing assembly 140 , intermediate shaft 150 , and base support member 160 . The crank member 130 includes a first shaft portion 132, a second shaft portion 134 parallel and offset relative to the first shaft portion 132, and a third shaft portion 136 interconnecting the first and second shaft portions.

In exemplary embodiments, such as in this embodiment, crank member 130 has two right-angled portions extending along its length and between its longitudinal ends. The first shaft portion 132 is a first axially extending shaft portion coaxial with the power take-off shaft of the drive handle and/or coaxial with the longitudinal axis XX'. The second shaft portion 134 is a second axially extending shaft portion and is an eccentric shaft portion relative to the motor drive shaft axis. The third shaft portion 136 is a crank arm that is a transverse shaft portion extending orthogonal to both the first and second shaft portions. The first shaft portion 132 is proximal of the PTO shaft and is substantially longer than the eccentric shaft portion 134 that is distal to the PTO shaft or proximal to the brush assembly. In an exemplary embodiment, the first shaft portion is at least twice the length of the second shaft portion.

The bushing assembly 140 has an inner bore coaxial with the longitudinal axis XX' and defines an elongate passage through which the coaxial shaft portion 132 of the crank member 130 passes and the coaxial shaft portion 132 of the crank member 130 is rotatably retained inside the elongated passage. The inner bore and elongated passage are shaped and dimensioned for retaining and maintaining the first shaft portion 132 of the crank member 130 coaxial with the longitudinal axis XX' such that during operation the first shaft portion 132 is constrained and supported as It rotates about its longitudinal axis XX' as its axis of rotation. To provide effective coaxial rotational support to the first shaft portion 132 of the crank member 130, a bushing assembly 140 is friction fit within the tubular housing. To mitigate relative rotational and longitudinal movement between the bushing assembly 140 and the tubular housing 110, cooperating stop means are formed on the bushing assembly 140 and the tubular housing 110, respectively. To provide more effective coaxial support to the crank member 130, a bushing assembly 140 is mounted on the first shaft portion 132 adjacent the crank arm. The bushing assembly has outer dimensions and shapes that conform to the inner dimensions of the elongated housing 210 to prevent relative rotational movement.

Bushing assembly 140 includes a first bushing member 142 and a second bushing member 144 that are axially connected. Each of the first bushing member 142 and the second bushing member 144 is made of an engineering plastic suitable for use as a support, such as polyoxymethylene (POM), and includes a solid body at the An elongated hole serving as a support hole is formed inside. Mating coupling means are formed at respective longitudinal ends of the first bushing member 142 and the second bushing member 144 to facilitate detachable connection in a longitudinal direction parallel to the longitudinal axis XX'. The respective coupling means are eccentrically arranged on respective end surfaces of the first bushing member 142 and the second bushing member 144 . In some embodiments, the first bushing member 142 and the second bushing member 144 are non-removable, eg, formed as a unitary member or a unitary member, to mitigate operational noise.

The intermediate shaft 150 is a coaxial shaft having a first longitudinal end for detachable coupling with the drive shaft 510 of the drive handle and a second longitudinal end for detachable coupling with the crank The member 130 (and more specifically the first shaft portion 132 of the crank member 130) is removably coupled. The intermediate shaft 150 includes engagement means at its longitudinal ends to facilitate releasable coupling engagement with the drive handle and crank member 130 . The intermediate shaft 150 has a generally circular cross-section, and the cross-sectional dimension of the circle defining its cross-section gradually decreases as the intermediate shaft 150 extends from the first longitudinal end to the second longitudinal end. The tapered shape of the intermediate shaft 150 facilitates adequate torque transfer as well as good robustness and durability while reducing material usage. The intermediate shaft 150 is integrally formed by POM. In some embodiments, crank member 130 is formed and secured within the second longitudinal end of intermediate shaft 150 by insert molding. In some embodiments, as shown in Figure 5, the first longitudinal end of the intermediate shaft 150 has a receiving portion that is shaped complementary to the shape of the drive shaft 510 of the electric toothbrush drive unit.

The base support member 160 is a rigid hollow structure and includes a first longitudinal end that will be in abutting contact with the drive handle during use and a second longitudinal end that is in coupling engagement with the intermediate shaft 150 . The base support member 160 is in the shape of an upside-down basket and is integrally formed of ABS. The base support member 160 includes a peripheral wall extending between the first longitudinal end and the second longitudinal end and extending about the longitudinal axis XX' to define a receptacle having a means for receiving the drive in a snug fit The inner compartment of the end portion 520 of the handle. The drive shaft 510 is movable relative to the end portion 520 of the drive handle. The base support member 160 , and more specifically the first longitudinal end of the peripheral wall of the base support member 160 , defines an access hole to the interior compartment of the base support member 160 . In some embodiments, the inner surface of the base support member 160 includes a slot or protrusion for receiving the coupling of the end portion 520 such that relative movement between the accessory 100 and the drive handle is limited .

The aforementioned peripheral wall is substantially circular, and the diameter of the peripheral wall gradually decreases as the base support member 160 extends from the first longitudinal end to the second longitudinal end. The tapered shape of the base support member 160 contributes to a strong structure while reducing material usage to promote good durability. At a position on the peripheral wall proximal to the second longitudinal end, there are opened two windows 162A, 162B facing at opposite positions that interfere with friction reduction.

When the brush assembly 120 is properly assembled, the bristle-carrying surface of the bristle disc 124 is substantially flush with the upper free end of the brush holder 116 with the base portion 126 within the toothbrush receiving portion; the brush assembly 120 is rotatable by the connecting pin 127 mounted on the brush holder 116, and wherein the connecting pin 127 serves as the axis of rotation of the brush assembly 120; the base support member 160 is fixedly mounted on the tubular housing 110 with the first longitudinal end of the base support member 160 in the tubular housing 110. outside of the housing 110 and in abutting contact with the first longitudinal end 112 of the tubular housing 110; the first longitudinal end of the intermediate shaft 150 is seated on the second longitudinal end of the base support member 160 such that the intermediate shaft 150 rotatable relative to the base support member 160 about the longitudinal axis XX'; the first end of the first shaft portion 132 of the crank member 130 is in coupling engagement with the second longitudinal end of the intermediate shaft 150; and the eccentricity of the crank member 130 The free end of the shaft portion is in driving engagement with the brush assembly 120 .

When toothbrush attachment 100 is attached to the drive handle such that drive handle drive shaft 510 is in driving engagement with intermediate shaft 150, reciprocation of drive handle drive shaft 510 about longitudinal axis XX' will act as a reciprocating motion about longitudinal axis XX' The reciprocating motion of φ is transmitted to the eccentric shaft portion 134 of the crank member 130 , but the radius of rotation is equal to the vertical separation distance between the center of the coaxial shaft portion 132 and the center of the eccentric shaft portion 134 . Due to the driving engagement between the eccentric shaft portion 134 and the brush assembly 120, and more specifically, due to the eccentric shaft portion 134 and the base portion 126 extending along the toothbrush axis YY' and intersecting the longitudinal axis XX' Driven engagement between the drive rails, eccentric reciprocating motion of eccentric shaft portion 134 about longitudinal axis XX' will be transmitted as reciprocating motion of brush assembly 120 about toothbrush axis YY'.

As shown in FIGS. 6, 6A, 6B1, and 6B2, an exemplary toothbrush head 200 includes a main housing 210, a brush head 220 having a brush axis Z-Z', and a drive coupling mechanism 280. As shown in FIGS. 7A and 7B , the main housing 210 includes a neck portion 213 and a head portion 215 . The neck portion 213 has a first axial end portion 214 for detachable attachment with the drive unit, a second axial end portion 212 abutting the head portion, and the first axial end portion 214 and the second axial end portion 214 Axial ends 212 interconnect tubular housing parts. The drive unit is, for example, the drive unit of a hand-held electric toothbrush drive unit commonly referred to as a handpiece. The tubular portion extends along a longitudinal axis XX' between the first and second axial ends and defines an elongated inner bore having a bore axis. The longitudinal axis is the central axis of the tubular portion along which the tubular portion is substantially laterally symmetrical. The longitudinal axis X-X' and the brush axis Z-Z' cooperate to define a lateral plane of symmetry. The elongated inner bore defines a through passage through which the drive coupling mechanism passes. The tubular portion has an elliptical cross-section as it extends along the longitudinal axis XX' and tapers as it extends from the first axial end to the second axial end. In this example, as the tubular portion extends from the first axial end towards the second axial end, the lateral direction of the tubular portion (which is orthogonal to the longitudinal axis XX' and includes the longitudinal axis X -X' and the lateral plane of symmetry of the brush axis Z-Z' orthogonal to) the width measured laterally decreases gradually. As the tubular portion extends from the first axial end towards the second axial end, the depth or thickness of the tubular portion measured in a direction orthogonal to the longitudinal axis XX' and orthogonal to the lateral direction gradually increases decrease. The rate of decrease in depth is faster than the rate of decrease in width, and the neck portion has a generally circular cross-section at the second axial end. The neck portion has a forward facing edge substantially parallel to the longitudinal axis X-X' and a rearward facing edge substantially at a constant acute angle with respect to the longitudinal axis X-X'. The forward-facing edge is the edge on the forward-facing side of the neck portion. The forward side is the side of the neck portion that has the same facing orientation as the bristles on the brush head. The forward facing edge is the edge on the plane containing the longitudinal axis X-X' and the brush axis Z-Z'. The rearward facing edge is on a diametrically opposite side of the forward facing edge, and the rearward facing edge is oriented opposite to the forward facing side.

The neck portion includes support means 260 for supporting the drive coupling mechanism. The support device 260 is a support device comprising a first axial end, a second axial end, and a peripheral wall extending between the first and second axial ends. An exemplary support device is a plug-like device having a generally cage-like structure. The cage-like support includes a window portion formed on the peripheral wall. The window portion has first and second axial ends, and includes a plurality of longitudinally extending spacer bars extending between the first and second axial ends.

The first axial end of the support means includes a circumferential flange portion located outside the neck portion and protruding radially away from the peripheral wall and radially away from the central axis of the support means. The radial extent of the flange portion is greater than or exceeds the radial extent of the inner bore at the first axial end of the neck portion such that the flange portion is blocked by the first axial end of the neck portion and cannot move beyond The first axial end of the neck portion enters into the neck portion. The flange portion includes a laterally extending flange surface that abuts the first axial end of the neck portion.

The second axial end of the support means includes a support portion and a through hole extending through the support portion. The support portion includes a laterally extending support platform on which the coupling end of the coupling shaft portion of the drive coupling mechanism rests. The through hole is aligned with the drive shaft of the handpiece and permits the drive shaft to extend through the support platform for coupling engagement with the drive coupling mechanism when the toothbrush head 200 is mounted on the handpiece.

A latch portion is formed on the support device at a location proximal of the second axial end. The latch portions project radially from the peripheral wall and latch into engagement with corresponding latch holes or corresponding latch recesses on the tubular portion.

The head portion 215 defines a brush disc holder and has a dome-shaped body within which a brush receiver 216 and receiver compartment are formed. The dome-shaped body has a generally hemispherical peripheral wall extending about a central axis and defines an open end portion and a closed end portion. The peripheral wall at the open end portion is substantially circular and centered on the brush axis Z-Z' as the central axis, and defines the open end hole. The peripheral wall tapers as it extends axially along the central axis away from the open end (ie, away from the front side) to define a circular closed end at the rear side. On the peripheral wall, at the connecting portion where the head portion and the neck portion meet, a connecting hole is formed. A drive coupling mechanism will extend through the coupling hole for coupling driving engagement with the head portion. A shaft retainer 217 is formed on the circular closed end and extends axially from the base of the closed end along the aforementioned central axis toward the open end. The shaft holder stops below the axial height of the coupling hole.

The toothbrush head 200 is held on the brush receptacle and supported by the brush shaft on the brush receptacle. The brush shaft defines a brush axis coaxial with the central axis, and during operation, when driven by the drive coupling mechanism, the brush head reciprocally rotates about the brush axis. The brush head 220 includes a disc portion with a plurality of bristles formed on one side of the disc portion forming groups of bristles called tufts, and a drive engagement portion formed on the other side of the disc portion . The disk portion, also referred to as the filament disk, has a disk axis that is the central axis of the disk portion and is coaxial with the central axis of the head portion. An exemplary brush head will reciprocately rotate about a disk axis during operation, and the disk axis is at an angle to or orthogonal to the central axis of the neck portion. The brush head 220 otherwise has the same description and functionality as the brush assembly 120, and the descriptions regarding and related to the brush assembly are incorporated herein by reference. The bristle filaments may include inelastic bristles (eg, nylon bristles) and/or elastic bristles.

The drive engagement portion is received within the receiver compartment and includes a shaft receiver for receiving the brush shaft and a drive slot for engagement with the drive end of the drive coupling. the drive slot is parallel to and offset from the brush shaft and is adapted to engage the drive end of the drive coupling such that rotation of the drive end about the axis of rotation of the drive coupling will cause rotation of the brush head about the brush axis, and Rotation of the brush head about the brush axis will cause upward and downward movement of the drive end along the drive slot. In order to facilitate the drive engagement between the drive engagement portion and the drive coupling mechanism, the drive slot is arranged next to and oppositely facing the attachment hole.

The drive coupling mechanism includes a coupling portion and a driving portion. The coupling part will receive the driving motion power from the driving unit, and continue to transmit the received driving motion power to the driving part. An exemplary drive motion originating from the drive unit is a reciprocating rotational motion about the axis of rotation of the drive handpiece. To provide sufficient rotational amplitude at the brush head to facilitate effective tooth brushing, the coupling portion includes an eccentric drive member that is displaced radially away from the axis of rotation to provide an amplified rotational amplitude. An exemplary drive portion is a crankshaft 230 that includes a first shaft portion 232 having a shaft axis, a second shaft portion 234 parallel to and radially displaced from the shaft axis, and connected to the first and second shafts. An intermediate portion that is partially orthogonal and interconnects the longitudinal ends of the first and second shaft portions. The first shaft portion 232 abuts the coupling portion and has a length that is much longer than that of the second shaft portion. The intermediate portion has a length equal to or less than the length of the second shaft portion as the eccentric shaft portion. The free longitudinal end of the first shaft portion distal to the second shaft portion 234 is wing-shaped to facilitate more reliable driving engagement with the driving portion.

The crankshaft 230 is rotatably retained on the bushing arrangement 240 and the first shaft portion 232 extends through the bushing arrangement 240 . The bushing arrangement 240 is fixedly fitted inside the neck portion and is prevented from rotating and moving relative to the main housing. During a brushing operation, the first shaft portion 232 of the crankshaft is driven to reciprocate about the shaft axis and to rotate relative to the bushing arrangement 240 . To facilitate the passage of the first shaft portion 232, the bushing arrangement 240 includes a through hole extending longitudinally through the bushing arrangement and having a bore axis aligned with the axis of rotation of the drive unit. During a brushing operation or when in drive engagement, the first shaft portion 232, the through hole of the bushing arrangement and the drive axis of the handpiece are axially aligned or coaxial.

The coupling portion 250 extends between the first axial end and the second axial end and includes a first portion 252 and a second portion 254 extending radially away from the first portion. The first portion is elongate, having a generally circular cross-section along its length, and extends from a first axial end abutting the support device 260 to a second axial end abutting the crankshaft 230 And tapered to thin. The first portion has a generally bullet shape and has a central axis coaxial with the center of the circle defining the circular cross-section of the first portion. The central axis of the first part is aligned with the drive axis of the drive shaft of the drive unit and is therefore also the axis of rotation of the coupling part.

The second portion is a side portion that includes a flange portion extending radially away from the first portion. The flange portion has a thickness that is substantially smaller than the thickness or diameter of the first portion and protrudes radially from the side of the first portion as a side fin portion or side fin portion. The width of the combined first part and the second part is slightly smaller than the width of the inner hole of the neck part, and the coupling part 250 will rotate following the rotation of the driving unit. The flange portion tapers as it extends from the first axial end to the second axial end to follow the taper of the neck portion.

When assembled, the coupling portion 250 is supported on the support device 260 and abuts the support platform surface of the support device. During a brushing operation, the coupling portion 250 is driven into reciprocating rotation by the driving unit due to the driving engagement between the driving unit and the coupling portion. The coupling portion 250 rotates while abutting against the bearing platform surface of the support device, and the bearing platform surface serves as a bearing surface. Due to the driving engagement between the coupling portion and the driving portion 230 , the reciprocating rotation is coupled to the driving portion 230 . The magnitude of the reciprocating rotation is amplified by the eccentric second shaft portion 234, and the amplified reciprocating rotation about the axis of rotation of the first shaft portion 232 is converted into a reciprocating rotation of the brush head about the brush axis. For example, the bristle disk or brush head will rotate back and forth at ±55 degrees about the brush axis corresponding to a ±25 degree rotation of the first shaft portion 232 .

The intermediate shaft 250 is elongate and extends between the first axial end 2501 and the second axial end 2502 . The first axial end is a first longitudinal end that includes coupling means for receiving the free end of the power drive shaft 510 that drives the handle. The second axial end is the second longitudinal end distal to the first longitudinal end and includes coupling means for receiving the free end of the crank member 230 .

The intermediate shaft 250 will serve as a power coupling portion to couple the driving power of the drive unit to the crank member, and includes a main shaft body extending between the first and second axial ends. The spindle body has a generally circular outer circumference, and the spindle body has generally circular symmetry along its length. The lateral dimension of the spindle body decreases as it extends from the first axial end to the second axial end, such that the spindle body tapers as it extends toward the brush holder. Tapering of the main shaft body or intermediate shaft 250 facilitates adequate torque transfer while maintaining good robustness and durability, as well as reducing material usage and reducing the weight of the intermediate shaft 250 . The first axial end includes a first bore for receiving the free end of the drive shaft of the handle unit, and the second axial end includes a second bore for receiving the free end of the crank member The first and second bores are coaxial bores and the bores are shaft end receiving bores. Each shaft end receiving hole has a non-circular inner cross-section that is complementary to the non-circular end of the received shaft end to reduce relative rotation between the received shaft and the main shaft body. The main shaft body is hollow over at least a major portion of its length.

The intermediate shaft 250 includes a fin-shaped member protruding radially outward from a lateral side of the main shaft body. The main shaft body and optional intermediate shaft 250 are integrally formed from high strength plastic such as POM. The radially protruding fin members will rotate or oscillate with the spindle body during brushing operations. The fin members extend substantially or nearly the entire length of the spindle body to improve torque resistance or torque transfer efficiency of the hollow spindle body. The fin members have a radial extent that has the added benefit of helping to align and maintain the spindle body with the drive shaft axis during high speed operation when the spindle body oscillates at high frequencies. Fins further reduce material usage while providing efficient alignment assistance, torque resistance or transferability, and/or other benefits of utilizing less material. The radial extent of the fins stops short of the inner circumference of the neck portion so that rotational movement of the fins is not hindered by the neck portion housing.

A portion of the main shaft body proximal to the first axial end has a cutout portion. The cutout portion includes a longitudinal cutout portion laterally offset from the central axis of the main shaft body, and a transverse cutout portion extending laterally and radially outward from a longitudinal end portion of the longitudinal cutout portion distal to the first axial end to form L-shaped cut. The L-shaped cutout increases elasticity and flexibility at the base portion of the main shaft body, which is proximal of the first axial end, to enhance torque transfer performance. An outer portion of the base portion adjacent to and defining the longitudinal cut forms a spring clip for resilient engagement with the output shaft of the drive unit. The spring clip is formed by the remaining outer portion of the base portion outside of the defining longitudinal cutout. The remainder is an upright elongated portion which slopes towards the spindle body axis as it extends away from the first axial end or as it extends towards the second axial end due to the taper of the spindle body, to define a spring clip for engagement with the output shaft end of the drive shaft.

To facilitate driving engagement between the drive unit and the drive coupling mechanism, a drive shaft receiver is formed on the first axial end of the coupling portion. The shaft receiving portion may be axisymmetric to facilitate a more reliable rotational motion coupling.

To assemble the drive coupling, a crankshaft is formed. The crankshaft may be formed from a steel pin of substantially uniform cross-section. Next, the first shaft portion of the crankshaft is inserted through the bushing arrangement 240 . An exemplary bushing arrangement is a single molded piece made from POM. After the first shaft portion has been inserted through the bushing arrangement 240, the free axial end of the first shaft portion 232 of the crankshaft is flattened or laterally enlarged to form a larger diameter than the steel pin or other portion of the crankshaft Winged ends with large radial extent. The drive portion and the coupling portion are then joined together, for example by placing the wing end in a mold and performing over-molding while the wing end is in the mold to form the coupling portion. As a result, as shown in FIGS. 6B and 6B1 , the coupling portion and the driving portion are integrally formed as a single piece. When assembled on the main housing, the first bend of the crankshaft 230, which is the bend that transitions from the first shaft portion 232, is located proximal to the thinnest end of the neck portion, and the second shaft portion 234 is located at the first The front of the shaft portion 232 and the central axis of the first portion of the coupling axis is located proximal to the rearward side of the neck portion.

During operation, the toothbrush attachment is mechanically coupled with the handpiece, and the drive shaft of the handpiece is in driving engagement with the drive coupling mechanism. When in driving engagement, the drive shaft of the handpiece is mechanically coupled with the coupling portion, the central axis of the first portion of the coupling portion is aligned with the shaft axis of the drive shaft, and the second portion (ie, the fin portion) of the coupling portion is located on the drive shaft in front of and in front of the axis of rotation of the first part. As the drive shaft reciprocates about its shaft axis, the coupling portion 250 follows the reciprocating rotation of the drive shaft and reciprocates about a rotational axis Y-Y' that is parallel and offset with respect to the longitudinal axis XX'. Reciprocating rotation of the coupling portion 250 about the axis of rotation drives the crankshaft to also rotate back and forth about the axis of rotation, and rotation of the crankshaft causes the second shaft portion to separate laterally or vertically from the first shaft portion 232 and the second shaft portion 234 The equal magnification radii reciprocately rotate to drive the brush head in reciprocating rotation about the brush axis.

While examples have been described to aid understanding, it should be appreciated that the examples are non-limiting examples. For example, although the brush axis Z-Z' is orthogonal to the longitudinal axis X-X', the brush axis may be at a non-right angle with respect to the longitudinal axis. For example, although the crankshaft has a double right angle portion, the crank or curved portion may have other angles than right angles without loss of generality.

As shown in FIGS. 8A-8D , the exemplary drive coupling assembly 380 includes a crankshaft 330 , a bushing assembly 340 and an intermediate shaft 350 . Bushing assembly 340 includes first bushing member 342 and second bushing member 344 . Crankshaft 330, bushing assembly 340, and intermediate shaft 350 have the same, similar, or equivalent features as described herein, and where appropriate and/or context permits, crankshafts 130, 230, bushings, The relevant descriptions of the sleeve assemblies 140, 240 and the intermediate shafts 150, 250 are incorporated herein, mutatis mutandis mutatis mutandis, in which reference numerals are appropriately increased by 100.

The bushing assembly 340 has a solid body and an elongated hole extending through the solid body that serves as a bearing hole for the crankshaft 330 to pass through. The bushing assembly 340 has outer peripheral dimensions that conform to the inner peripheral dimensions of the elongated neck portion of the main housing of the toothbrush attachment to prevent relative rotation between the bushing assembly 340 and the neck portion about the longitudinal axis of the neck portion . The outer circumference dimension here is the dimension of the portion around the longitudinal axis of the neck portion, and is the lateral circumference. Bushing assembly 340 has a length comparable to but slightly shorter than the length of the first shaft portion of the crankshaft to facilitate stable rotation or oscillation of the crankshaft relative to the neck portion while permitting rotation of the eccentric shaft portion relative to the solid body. Bushing assembly 340 includes axially extending grooves formed on the outer peripheral surface of the solid body forming the bushing assembly. Each axial groove is a through-slot extending from one axial end of the solid body to the opposite axial end to permit the bushing assembly to be subjected to an axial direction protruding radially from the inner peripheral surface of the neck portion. The ribs slide into the neck portion as they guide. An axial rib protruding from the inner surface of the neck portion will engage the axial rib to prevent relative rotation of the bushing assembly 340 relative to the neck portion about the neck portion axis. In an exemplary embodiment, such as in this embodiment, bushing assembly 340 has a circumferential dimension commensurate with the circumferential dimension of the neck portion.

In the exemplary embodiment, first bushing member 342 and second bushing member 344 are connected by abutting their corresponding inward lateral surfaces, and are welded together, such as by ultrasonic welding, to form the bushing Component 340 . The bearing hole of bushing assembly 340 is formed by the cooperation of the first and second bushing members. 8C, 8D and 9A, the second bushing member 344 includes a first lateral portion 3441, a second lateral portion 3442, and an intermediate portion 3443 interconnecting the first and second lateral portions. The intermediate portion is a laterally indented portion that cooperates with the first and second lateral portions to define an axial recess that is open to the first bushing assembly 342 . The axial recess has a lateral clearance that is commensurate with the width or lateral dimension of the shaft body and slightly larger to permit rotation relative to the second bushing member 344 . The lateral gap is defined by the cooperation of the respective opposing facing side walls of the first and second lateral portions. The first and second lateral portions 3441, 3442 are distributed on opposite sides of the recess, and the direction of separation defines the lateral direction herein. The axial recess has a lateral depth that is comparable to or slightly greater than the width or lateral dimension of the shaft body to permit rotation relative to the second bushing member 344 . The lateral direction is orthogonal to the lateral and axial directions.

The first bushing member 342 includes a first lateral portion 3421, a second lateral portion 3422, and an intermediate portion 3423 interconnecting the first and second lateral portions 3421, 3422. The intermediate portion 3423 is a lateral projection that cooperates with the first and second lateral portions to define an axially extending projection facing the second bushing member 344 . The laterally projecting intermediate portion 3423 has a forward-facing or laterally facing surface that cooperates with the intermediate portion 3443 of the second bushing member 344 to define the bearing aperture.

Mating coupling means 346A, 346B, 348A, 348B are formed on corresponding surfaces of the first bushing member 342 and the second bushing member 344 to facilitate connection in a direction orthogonal to the longitudinal axis XX' connect. For example, the coupling means includes a lateral projection 346A extending from an end surface of the second bushing member 344, and a lateral aperture 346B disposed inside the first bushing member 342 at a position complementary to the lateral projection 346A. When the first bushing member 342 and the second bushing member 344 are assembled, the lateral protrusions 346A are secured within the lateral holes 346B. Corresponding coupling means may also be projections 348A arranged on the end surface of the second bushing member 344 and slots 348B arranged at the edge of the first bushing member 342 at positions complementary to projections 348A. While examples have been described to aid understanding, it should be appreciated that these examples are non-limiting examples. For example, both protrusions and holes may be provided on the first bushing member, and corresponding holes and protrusions may be provided on the second bushing member. For example, the protrusions may be cylindrical, semicircular or rectangular. For example, only holes or slots may be provided on the first bushing member or the second bushing member. In the case where only the holes are provided, the first bushing member and the second bushing member are assembled along the extending direction of the protruding portion. Where only the slot is provided, the projections can enter the slot from multiple directions so that the first bushing member and the second bushing member can be rotatably assembled.

To assemble the drive coupling assembly, the first shaft portion 332 of the crankshaft 330 is inserted into the axial recess of the second bushing member 344 . After the first shaft portion 332 has been positioned within the axial recess of the second bushing member 344, the first bushing member 342 is coupled to the second bushing member 344 by means of matching coupling means 346A, 346B, 348A, 348B . As a result, the axial recess of the second bushing member 344 is closed by the first bushing member 342 . As shown in FIG. 9A , the first shaft portion 332 is located forward of the laterally protruding intermediate portion 3423 of the first bushing member 342 and is sandwiched between the first bushing member 342 and the second bushing member 344 .

Reference number table

Claims (24)

Claims 1. A toothbrush accessory for removably attaching to a motor drive unit of an electric toothbrush, wherein the motor drive unit includes a motor and a drive shaft, the drive shaft being driven by the motor to surround the drive The axis of rotation of the shaft rotates reciprocally, the toothbrush attachment including: a main housing including a tubular neck portion having a longitudinal axis and a head portion defining a toothbrush receiving portion; a toothbrush head rotatably mounted on the the toothbrush receiving portion of the head portion and the rotatable brush axis; and a drive coupling mechanism mounted inside the neck portion and having an axis of rotation; The drive coupling mechanism comprises a crankshaft, bushing means and a coupling shaft portion; the coupling shaft portion comprises engagement means at an axially free end, the engagement means being adapted to interface with the drive shaft of the motor drive unit A releasably coupled drive engagement is made to receive rotational drive power from the drive shaft and transmit the received rotational drive power to the crankshaft for driving the toothbrush head around the brush The axis rotates reciprocally, and the coupling shaft portion and the crankshaft are integrally formed as a unitary member and the crankshaft is rotatably mounted on the bushing device. 2. The toothbrush accessory of claim 1, wherein the coupling shaft portion comprises an axisymmetric first portion and a non-axisymmetric second portion, the non-axisymmetric second portion being symmetric from the axis The first portion is a radially outwardly projecting side portion; and the axisymmetric first portion has a longitudinal central axis aligned with the rotational axis. 3. The toothbrush attachment of claim 2, wherein the axisymmetric first portion tapers as it extends toward the head portion. 4. The toothbrush accessory of claim 2 or 3, wherein the side portion comprises a fin-like flange portion having a radial extent from the axisymmetric first portion, and The finned flange portion tapers as it extends axially toward the head portion. 5. The toothbrush attachment of any one of claims 2 to 4, wherein the neck portion includes a forward-facing edge and a rearward-facing edge, the forward-facing edge and the rearward-facing edge located at a location containing the rotation axis and the plane of the brush axis, and the neck portion is laterally symmetrical about the plane; and the finned flange portion is proximal of the forward facing edge, and the axis is symmetrical The first portion is located proximal of the rearward facing edge. 6. The toothbrush accessory of any preceding claim, wherein the crankshaft (230) includes a first shaft portion (232) aligned with the axis of rotation and an eccentric offset relative to the axis of rotation a shaft portion (234); the neck portion includes a forward facing edge and a rearward facing edge that lie on a plane containing the rotational axis and the brush axis, and the neck portion The portion is laterally symmetrical about the plane; and the axis of rotation is proximal of the rearward facing edge and the eccentric shaft portion is proximal of the rearward facing edge. 7. The toothbrush attachment of claim 6, wherein the neck portion has an elliptical cross-section relative to the longitudinal axis of the neck portion, and the axis of rotation is parallel to the forward facing edge and at a small acute angle with respect to the rearward facing edge. 8. The toothbrush attachment of claim 6 or 7, wherein the crankshaft (230) comprises an enlarged wing-like portion at a free axial end of the first shaft portion (232), and the enlarged The wing portion is embedded inside the coupling shaft portion by overmolding. 9. The toothbrush accessory of claim 8, wherein the bushing means is a longitudinally extending through hole extending between two axial ends and having a longitudinally extending through hole extending between the two axial ends an integral device, and the wing portion has a radial extent exceeding the clearance of the through hole. 10. A toothbrush attachment according to any preceding claim, wherein the neck portion comprises support means (260) having a bearing platform surface, the drive coupling mechanism being rotatably supported on the On the surface of the support platform, the support device (260) includes a first axial end portion, a second axial end portion and extending between the first axial end portion and the second axial end portion A support device for the peripheral wall; and the support device has a cage-like structure. 11. A toothbrush head for attachment to an output drive shaft of a drive handle of an electric toothbrush, the toothbrush head comprising a tubular housing, a bristle carrier and a crank member: the tubular housing extending along a longitudinal axis, The bristle carrier is mounted at or near the longitudinal end of the tubular housing and is rotatable about the carrier axis, and the crank member extends inside the tubular housing to drive drive from the driven end Rotation is transmitted to a drive end; the drive end is offset relative to the driven end; the crank member is supported for rotation within the tubular housing by a bushing assembly including a first A bushing member and a second bushing member, the bushing assembly is rotatably secured to the crank member. 12. The toothbrush head of claim 11, wherein the crank member passes through an aperture of the first bushing member, the aperture having a diameter less than an offset distance to prevent the driven end from passing through the first bushing member. The first bushing member is rotatably secured to the crank member when the second bushing member is mounted to the crank member. 13. The toothbrush head of claim 12, wherein the second bushing member includes a slot along the longitudinal axis for removably attaching to the crank member. 14. The toothbrush head of claim 11, wherein the crank member is a straight metal rod that is bent to form a first shaft portion, a second shaft portion, and the first shaft A crank arm partially interconnected with the second shaft portion. 15. The toothbrush head of claim 14, wherein the first shaft portion and the crank arm are at right angles; the crank arm and the second shaft portion are at right angles. 16. A toothbrush head according to claim 14 or 15, wherein the first bushing member can be along the first shaft portion when the second bushing member is detached from the crank member Move and stop at the crank arm. 17. The toothbrush head of claim 11, wherein the toothbrush head includes an intermediate shaft that is a coaxial shaft and has the output drive shaft for removably coupling with the drive handle and a second longitudinal end secured to the crank member. 18. The toothbrush head of claim 17, wherein the intermediate shaft is secured to the crank member by insert molding. 19. A toothbrush head according to claim 17 or 18, wherein the second bushing member includes a slot along the longitudinal axis for insertion between the intermediate shaft and the first bushing member The crank member is detachably connected to the crank member at a position between the two. 20. A toothbrush head according to any preceding claim, wherein the toothbrush head comprises a base support member fixedly mounted on the tubular housing, the base support member comprising a peripheral wall at the first Extending between the longitudinal end and the second longitudinal end and about the longitudinal axis to define a receiver having an interior compartment for tightly fittingly receiving the drive handle A portion of the output drive shaft; the peripheral wall is provided with at least one window to reduce the interference area between the base support member and the drive handle. 21. The toothbrush head of claim 20, wherein the peripheral wall defines two opposite windows. 22. The toothbrush head of claim 11, wherein the crank member passes through the groove of the first bushing member, when the second bushing member is mounted to the first bushing member, The crank member is prevented from leaving the groove. 23. A toothbrush head according to claim 12 or 22, wherein the second bushing member is provided with coupling means and the first bushing member is provided with corresponding coupling means such that when the coupling means and all The second bushing member is fixedly mounted to the first bushing member when the corresponding coupling means are engaged. 24. A toothbrush head according to any preceding claim, wherein the bristle carrier comprises guide grooves extending in a direction parallel to the carrier axis.

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