A semi-free rotating crankshaft actuator (80) for an oral healthcare appliance comprises a chamber (82), a spring loadable plunger (85), and a crank mechanism (88). The crank mechanism (88) comprises at least a drive pin (90) rotatably driven about a drive axis (96), and a crank shaft (94) semi-freely rotatable about the drive axis, wherein the crank shaft (94) couples to the spring loadable plunger (85) and is partially driven about the drive axis (96) via (i) the drive pin (90) in a first operational mode, (ii) the spring loadable plunger (85) in a second operational mode, and (iii) the drive pin (90) in a third operational mode that comprises at least completing an incomplete actuation of the plunger (84) from an undesired end position to the desired end position in response to the crank shaft (94) pushing the plunger (84) from the undesired end position to the desired end position.

A tracking attachment for an oral care implement that includes a housing and a tracking unit configured to track position, orientation, or movement of the oral care implement. The housing may define a receiving cavity that is configured to receive a portion of the oral care implement. The housing may include a first housing portion having an inner surface that defines a first portion of the receiving cavity that is open at both of the first and second ends of the first housing portion and a second housing portion that mates with the first housing portion to detachably couple the second housing portion to the first housing portion. The second housing portion may have an inner surface that defines a second portion of the receiving cavity that is open at the second end of the second housing portion.

A brush head is provided on the front surface at a distal-end-side part of a neck of a replaceable brush. A fitting shaft portion is provided on a planting base of the brush head so as to protrude rearward and penetrate through a support wall portion of the neck. A shaft hole is formed at a rotation center of a brush head body of the brush head so as to extend frontward from a rear surface of the brush head body. The neck has ahead support shaft mounted to the shaft hole so as to rotatably support the brush head. A front end of the head support shaft is located frontward of a rear surface of the planting base, and power from the driving portion is transmitted to a rear part of the fitting shaft portion.

A powered brush has two different brushes for different purposes that are selectively vibrated for powered cleaning. The brushes may be a tooth brush and an interdental brush that are separately operated at different frequencies. One or more buttons or switches provide control signals to the powered brush to selectively actuate the different brushes. A controller connects a motor to a power source such as a battery based on the control signals. The controller may include a timer for actuating the selected brush for a given time period.

A linear motor includes an armature mounted for driven linear oscillation substantially along a longitudinal direction; a secondary mass mounted for linear oscillation substantially along the longitudinal direction; and a coupling unit for coupling the armature and the secondary mass. The coupling unit includes at least two coupling spring assemblies and at least a coupling element, the coupling spring assemblies being arranged in planes perpendicular to the longitudinal direction and being spaced apart from each other, and the coupling element being fixedly connected with the coupling spring assemblies.

A head module capable of reciprocal rotation for an electric cleaning apparatus comprises cleaning elements, a housing and a driven rod disposed in a hollow inner cavity of the housing, wherein the rod is provided with a hollow cavity body for accommodating a drive shaft; at least one gap is provided in a region surrounding the hollow cavity body; at least one inner side notch is distributed on a side wall of the inner cavity, for accommodating a protrusion; the rod further comprises a partially cylindrical or conical cavity body region. When the drive shaft is not yet inserted into the rod, there is a gap between the notch and the protrusion in a direction perpendicular to the rotation axis (L1) of the drive shaft. The length of the gap is greater than or equal to the amount of single-side interference between the rod and the drive shaft.

A plurality of mass-produced multi-component housings having a length and comprising at least a first component comprising a first plastic material, a second component comprising a second plastic material, and a third component comprising a third plastic material. Each of the housings includes at least one tolerance-elimination element made of the second plastic material and longitudinally attached to the first component along the housing's longitudinal axis. The tolerance-elimination element has an average length extending parallel to the housing's longitudinal axis, which average length is at least ten times less than the length of the housing. The third component at least partially forms an outer surface of the housing, so that the tolerance-elimination element is at least partially overmolded by the third plastic material. The tolerance-elimination elements of the plurality of multi-component housings are structured to cause lengthwise maximal dimension variations of the length L among the individual multi-component housings to be not greater than 0.1 mm.

A personal care cleaning device (10) including a housing (12), a resonant drive actuator (20), which includes a rotor (24) having a first moment of inertia (J.sub.r) and a stator (22) having a second moment of inertia (J.sub.s); a first plurality of leaf spring elements (60) having a first spring constant (k.sub.rh), each leaf spring element of the first plurality of leaf spring elements (60) being connected the housing (12) and to the rotor (24) such that each leaf spring element of the first plurality of leaf springs elements (60) extends radially from the rotor (24) to the housing (12), each leaf spring element of the second plurality of leaf spring elements (62) being connected to the housing (12) and engaging with the stator (22), wherein the ratio of the first (k.sub.rh) and second (k.sub.sh) spring constants is sufficiently similar to the ratio of the first (J.sub.r) and second moments (J.sub.s) of inertia such that there is substantially no resulting torque transmitted to the housing (12) during operation.

A tooth brush device having bristle touch-points composed of a polymer material (e.g., silicone) provides improved biofilm removal from teeth. The tooth brush device comprises a head with an apex, a base opposite the apex, a front surface, and a back surface opposite the front surface. The front surface of the head includes bristle touch-points arranged along rows. The rows are arranged orthogonal to the longitudinal axis of the head extending from the apex of the head to the base of the head. Each of a plurality of the bristle touch-points is a single solid elongate structure extending from the head and is composed of a polymer material. The device further includes a neck coupled to the base of the head and a handle coupled to the head via the neck.

A battery chassis with stroke limiter (70) for a power toothbrush (10) configured to improve the durability of a power toothbrush (10) and to simplify the assembly process. The battery chassis stroke limiter (70) provides a secure housing for the battery (80), while tolerance compensation leaves (71, 72), and battery hardstops (75, 76, 77) provide for drop mitigation protection and shock protection, as well as vibration mitigation.