FIELD OF THE INVENTION

The present invention relates generally to the technical field of electrical toothbrushes, and more particularly to an electrical toothbrush head that is in secure contact engagement with a vibration core.

DESCRIPTION IF THE RELATED ART

With the continuous heightening of living standard, electrical toothbrushes have been gaining popularity in the market. An electrical toothbrush uses fast rotation or vibration of a vibration core to induce high frequency vibration in the brushing head of the toothbrush head by which tooth paste is instantaneously decomposed into fine foaming that goes deeply into gaps between teeth for cleaning. On the other hand, the vibration of the bristles helps enhance oral cavity blood circulation and also provide an effect of massaging to the gingival tissues.

An electrical toothbrush is made up of a toothbrush handle and a toothbrush head. The toothbrush handle includes a vibration core arranged at a top thereof. The toothbrush head is formed, in an interior thereof, with a core channel having a bottom opening. The toothbrush head is provided with bristles. The vibration core of the toothbrush handle is inserted, from bottom to top, into the core channel of the toothbrush head, and the vibration core is set in contact engagement with the core channel. In this way, high frequency vibration of the vibration core can drive the bristles of the toothbrush head to vibrate in order to achieve an effect of brushing teeth with the bristles.

In the known art, when the toothbrush handle is brought into mating engagement with the toothbrush head, the vibration core of the toothbrush handle is inserted into the core channel and direct contact engagement between the vibration core and an inside surface of the core channel help realize transmission of vibration. However, since the contact engagement between the vibration core and the inside surface of the core channel is in firm contact and the engagement may not be stable and secure so as to affect the transmission of vibration between the vibration core and the toothbrush head.

SUMMARY OF THE INVENTION

An objective of the present invention is to provide an electrical toothbrush head that is in firm contact engagement with a vibration core in order to overcome the problem that the contact engagement between the electrical toothbrush head and the vibration core is unsecure.

The present invention is implemented as follows. An electrical toothbrush head for being in secure contact engagement with a vibration core comprises a toothbrush body, the toothbrush body being provided, in a lower part thereof, with an insertion compartment that has a bottom opening, an insertion piece being inserted through the bottom opening and disposed in the insertion compartment, the insertion piece being provided, in a lower part thereof, with a core channel into which the vibration core in a flat form is insertable, the insertion piece being formed, in a bottom thereof, with an insertion opening in communication with the core channel;

the insertion piece being provided in a sidewall thereof with a sideway slot, the sideway slot penetrating to outside of the insertion piece and the core channel, an elastic bar that is integrally formed as one piece and elastically swingable being arranged in the sideway slot, the elastic bar being arranged to extend in an axial direction of the core channel, an upper end of the elastic bar being fixedly connected to the sidewall of the insertion piece, a lower end of the elastic bar being arranged in a movable manner;

the core channel having an inner surface that forms a contact engagement surface arranged to face the elastic bar, the contact engagement surface extending regularly and smoothly in an axial direction of the core channel, the elastic bar having a middle portion that bugles and curves toward the core channel to form a curved section, a contact engagement spacing being present between the curved section and the contact engagement surface, the contact engagement spacing being formed in a middle of the core channel, the contact engagement spacing being smaller than a thickness of the vibration core;

the vibration core including two core side surfaces that are opposite to each other, such that when the vibration core is inserted into the core channel through the insertion opening of the insertion piece, the vibration core extends through the contact engagement spacing to set the contact engagement surface in contact and pressing engagement with one of the core side surfaces of the vibration core, through surface engagement therebetween, another one of the core side surfaces of the vibration core being in contact and pressing engagement with the curved section and pushing the elastic bar to elastically deform away from the contact engagement surface; and

an outside surface of the curved section surrounding and defining a curved trough, the curved trough being completely filled with a single-piece elastic filler block, the elastic filler block contacting and pressing an inside surface of the insertion compartment and being in a compressed state.

Further, the curved trough is provided therein with a constraint plate that is arranged horizontal, an inner end of the constraint plate being fixedly connected to a middle of the outside surface of the curved section, an outer end of the constraint plate extending toward an inside surface of the insertion compartment and forming a constraint spacing with respect to the inside surface of the insertion compartment, the elastic filler block covering and enclosing entirety of the constraint plate.

Further, the constraint plate divides the curved trough into two separation troughs that are respectively arranged at upper and lower sides, the elastic filler block filling up both of the two separation troughs, the constraint plate being formed with multiple penetration holes that extend longitudinally through the constraint plate, the elastic filler block filling up the multiple penetration holes.

Further, the separation troughs are provided therein with multiple horizontal pillars that are set horizontal, the multiple horizontal pillars being sequentially arranged at intervals in an axial direction of the core channel; the horizontal pillars have an inner end fixedly connected to the outside surface of the curved section, the horizontal pillars having an outer end extending toward the inside surface of the insertion compartment and being arranged to be spaced from the inside surface of the insertion compartment, the elastic filler block covering and enclosing the multiple horizontal pillars.

Further, the curved section has a curved side surface facing toward the contact engagement surface, a middle of the curved side surface being recessed in a direction away from the contact engagement surface to form a recessed groove, an interior of the recessed groove being filled up with a silicone rubber body; the curved side surface includes two planar pressing surfaces, the two planar pressing surfaces being respectively located on upper and lower sides of the recessed groove, the two planar pressing surfaces being each arranged in a manner of being flush with an outside surface of the silicone rubber body; when the vibration core is inserted into the core channel, the two planar pressing surfaces and the outside surface of the silicone rubber body are each contacting and pressing against the core side surface of the vibration core.

Further, the insertion piece includes a projection plate, the projection plate being arranged to extend in an axial direction of the core channel, the contact engagement surface of the core channel being formed on an inner side of the projection plate, the projection plate being formed with a hollow cavity that includes a bottom opening, the hollow cavity being arranged to extend in the axial direction of the core channel, the hollow cavity and the contact engagement surface being arranged to separate from each other.

Further, the elastic bar includes, in an upper part, a deformable section, an upper end of the deformable section being fixedly connected to a side wall of the insertion piece, a lower end of the deformable section being joined to the curved section; the deformable section includes an inside surface facing the core channel, the inside surface of the deformable section being a regular and smooth longitudinal surface, the deformable section including an outside surface facing the inside surface of the insertion compartment, the outside surface of the deformable section being of a curved recess facing toward the core channel.

Further, the insertion piece is provided, on an outside surface, with a planar section119in the form of a regular and smooth longitudinal surface, the planar section and the contact engagement surface being arranged opposite to each other, the planar section being arranged to extend in the axial direction of the core channel, a rib being formed on and raised from a middle portion of the planar section, the rib being arranged to extend in the axial direction of the core channel and spanning over entirety of the planar section.

Further, the insertion piece is provided, in an outside surface of an upper part thereof, with two retaining notches, the two retaining notches being arranged opposite to each other, the retaining notches having two ends horizontally extending through the insertion piece, the insertion compartment being provided with two retaining blocks raised from an inside surface thereof, the two retaining blocks being respectively insertable into the retaining notches.

Further, the insertion piece is provided, in an outside surface of a lower part thereof, with a circumferential groove, the circumferential groove being of a circumferential arrangement circling about the axial direction of the insertion piece, the insertion compartment being provided with multiple engagement projections raised from an inside surface thereof, the multiple engagement projections being sequentially and circumferentially arranged at intervals, the multiple engagement projections being insertable into the circumferential groove.

Compared to the known techniques, the present invention provides an electrical toothbrush head that can be set in secure contact engagement with a vibration core, wherein in combination with the toothbrush handle, the vibration core is inserted into the core channel, and the vibration core is clamped between the contact engagement surface and the curved section. Due to the elastic bar being deformed to swing outward, the elastic filler block is compressed. As such, the restoring forces of the elastic filler block and the elastic bar drive the curved section to elastically contact and press the vibration core, where the contacting and pressing is achieved in a secured and firm manner and allowing for elastic connection in cooperation with high frequency vibration of the vibration coreg.

