HK1000337B - Case for an electric toothbrush and its method of manufacture - Google Patents

Description

The invention relates to a housing for an electrical personal care device, in particular a dental cleaning device, containing electrical components surrounded by a casting mass by filling the casting mass into the housing, connected by an electrical cable through a cable opening in the housing, and a method for manufacturing the housing.

The applicant's commercial electrical tooth cleaners show that such a housing has a cable compartment separated from the area containing the electrical components by an interlayer. The interlayer contains two openings through which the electrical cable connected to the electrical components is passed. The other opening is used in the manufacture of the housing to fill the casing into the area containing the electrical components. To this end, a filling device is inserted into this opening so that the liquid casing can flow back into the interior of the housing and surround the electrical components. A pre-filling device is placed in the middle of the casing to fill the casing without further displacement of the oil.

The purpose of the invention is to create a housing, in particular for an electric tooth cleaning device, and a method for its manufacture, which is improved in terms of the required material requirements and the required manufacturing steps.

The problem is solved by the fact that, in the case of a housing of the type mentioned at the outset, the cable opening is located in an outer wall of the housing and is the only opening of the housing to the electrical components.

According to the invention, the cable opening is no longer provided in an intermediate wall, but directly in the outer wall of the housing. An intermediate wall or similar is no longer present. The function of the intermediate wall, i.e. the separation of the electrical components from the cable compartment, is taken over by the filled casting mass. The resulting material saving and reduction of the required manufacturing steps is obvious.

Another advantage is that the casting mass not only surrounds the electrical components but also at least partly the electrical cable, thus providing a relief of tension to the electrical cable, so that no further arrangements need be made in this respect.

Furthermore, the invention provides for only one opening to the electrical components, the cable opening, which also clearly represents an improvement, particularly as regards the manufacture of the enclosure according to the invention.

This cable opening allows the electrical cable to be inserted or removed into the cable compartment behind it as required, the cable compartment having the advantage of being closed on all sides except the cable opening and being formed by essentially smooth surfaces inside, thus protecting and protecting the electrical cable.

In the case of a further development of the invention, the casting surface of the standing housing has a surface which is either horizontal or inclined to the horizontal. In particular, the latter alternative, i.e. a sloping surface of the casting, enables the electrical components to be completely surrounded by the casting surface and thus insulated, but also to allow a smaller amount of casting to be filled into the interior of the housing than before.

The advantage of the invention is that the electrical cable cannot be damaged by the supporting strips.

In the case of an electric tooth-cleaning device, a user may use a hand-held device with a rotating brush part separated from the mains voltage. To charge the battery contained in the hand-held device, the hand-held device must be connected to the charging device. This may be done, for example, by means of electrical contacts or similar, the required charging device being housed in the housing of the invention.

In a process of the type described at the outset, the above problem is solved by introducing the casting mass into the housing by means of a filling device through the cable opening.

The cable opening has a dual function: on the one hand, it serves as an opening for the electrical cable, but on the other hand, the casting mass is also compacted into the inside of the housing through the cable opening. For this purpose, the filling device is introduced into the cable opening when the electrical cable is plugged in and the liquid casting mass is introduced into the inside of the housing. Once the required amount of casting mass has been filled, the filling device is retracted and the casting mass can be hardened. The surface of the first-stayed casting mass can then form one of the surfaces of the cable housing. If this is the case, the surface can be connected through the opening and the electrical cable can be inserted into the cabling.

In the case of a design of the invention, the casing for filling the casting mass is moved by means of a conveyor into a filling position which has a filling angle to the horizontal, thus making it much easier to fill the casting mass into the interior of the casing.

In a more advantageous development of the invention, the casing for curing the casting mass is moved by means of the conveyor into a position which is either approximately horizontal or has an angle of inclination to the horizontal, thus producing either the horizontal surface of the casting mass or the surface which is arranged below the angle of inclination.

It is useful to place the housing on a corresponding inclined plane, which allows the desired inclination angle for filling or curing the casting to be achieved in a particularly simple way, by moving the conveyor with the housing up or down the said inclined plane only and by placing the housing on the inclined plane for filling or curing the casting.

The following illustration shows the following examples of the advantages and applications of the invention.

It shows: Fig. 1a schematic representation of a housing of an electric tooth cleaner in a cut side view, where a straight casting has been filled into the interior of the housing by means of a filling device,Fig. 2a schematic representation of the housing of Fig. 1 in a cut side view, which has been placed in a horizontal position in a first embodiment for curing the casting in a horizontal position,Fig. 3a schematic representation of the housing of Fig. 1 in a cut side view, which has been placed in an inclined position in a second embodiment for curing the casting in a horizontal position,Fig. 4a schematic representation of the housing of Fig. 1 in a cut side view, which has been placed in a horizontal position in a second embodiment for curing the casting in a horizontal position,Fig. 4a schematic representation of the housing of Fig. 1 in a cut side view, which has been cut in a horizontal position in a plane of Fig. 1A.

Figure 1 shows a case 1 for an electric tooth cleaner.

The housing 1 consists essentially of a cup-shaped top 2 and a flat bottom 3 approximately corresponding to the opening of the top 2. On one side, the top 2 is provided with a protruding cover 4 starting from a rim of its cup-shaped top. The bottom 3 extends into the area of the cover 4 and completely closes the opening of the cup-shaped top 2 and the cover 4. From the cover 4 a round support 5 with a cross section points out in approximately the same direction as the cover 2 is shown.

If the housing 1 is on the floor 3 or otherwise fixed in this position, the support 5 is pointed upwards approximately vertically and the floor 3 extends approximately horizontally, allowing a handheld device belonging to the electric tooth cleaner to be mounted on the support 5 with an associated recess.

The handheld device contains an electric motor that is driven by a battery. The electric motor can rotate the bristles of a bristle part. A user can thus clean their teeth with the rotating bristles of the handheld device when the handheld device is removed.

To recharge the battery, the user must plug the handheld device into the 5 supports of housing 1 and then transmit electrical energy to the handheld device by means of an inductive transmission. To this end, the handheld device and housing 1 have corresponding devices, including a coil 6 in housing 1. A circuit board 7 is placed in housing 1 approximately parallel to the floor 3 and extends approximately over the entire opening of the cup-shaped top 2. On the circuit board 7 there are a number of electrical components 8 which are welded to the circuit board 7. These electrical components 8 are, for example, electrical resistors, capacitors, transistors, etc.

In total, the electrical components 8 constitute an electrical charging device for recharging the battery in the handheld device mentioned above.

The circuit board 7 with the electrical components 8 is fixed by means of support strips 9 inside the housing 1.

The height of the upper part 2 is chosen so that there is a free space above the electrical components 8 which will be described in more detail.

An electrical cable 10 is firmly connected to the circuit board 7 and is used to supply the charger with electrical energy, for example in the form of a mains voltage, so that the circuit board 7 and the electrical components 8 are conductive when on.

The electrical cable 10 is drawn out of the housing 1 through a cable opening 11 and the cable opening 11 is located in a cup-shaped outer wall 12 of the upper part 2 in the area of the free space of the upper part 2 which is to be explained.

In the manufacture of housing 1, the circuit board 7 with the electrical components 8 including the coil 6 and other means of inductive transmission is first inserted into the upper part 2, the electrical cable 10 is inserted through the cable opening 11 and the upper part 2 is then securely closed with the help of the ground 3.

The housing 1 is now placed in a filling position as shown in Figure 1. In this filling position the housing 1 has a filling angle a to the horizontal, which in the example described is approximately 70 to 80 degrees. This filling angle a is selected so that the cable opening 11 is in a nearly horizontal position.

In the lower part of Fig. 1 the horizontal is drawn as a line, so that the fill angle a is, for example, between this line and floor 3.

In the technical sense, the filling angle a is achieved by holding the housing 1 on a conveyor device which transports the housing 1 from one station to the next station of the production line and by moving this conveyor together with the housing 1 up or down a corresponding inclined plane.

In the filling position, a filling device 13 is attached to housing 1, which may be a tubular filling nozzle, for example. The filling device 13 is then inserted into cable opening 11 and a liquid casting mass 14 is then filled into the housing 1 by means of the filling device 13. The amount of casting mass 14 to be filled is chosen in the present example so that the housing 1 is filled about halfway with casting mass 14. The filling device 13 is then withdrawn again.

The horizontal surface of the filled casting mass 14 in the filling position, i.e. with inclined housing 1, is marked in Figure 1 by the reference figure 15.

In a first embodiment, the housing 1 is placed in a roughly horizontal position after filling with the still liquid casting medium 14 as shown in Figure 2. The horizontal is indicated by a line at the bottom of Figure 2. The surface of the filled casting medium 14 is marked in Figure 2 by the reference number 16. This surface 16 is arranged approximately parallel to the floor 3 and the electrical components 8 including the circuit board 7 are located in the area of the housing 1 filled with the casting medium 14.

In the second embodiment, shown in Fig. 3, the housing 1 is placed in an inclined position after filling with the still liquid casting medium 14. In this hardened position, the housing 1 has an angle of inclination b to the horizontal, which is approximately 40 to 50 degrees in the example described. In the lower part of Fig. 1 the horizontal is drawn as a line, so that the angle of inclination is bound, for example, between this line and the floor 3. The surface of the filled casting medium 14 is marked with the reference number 17 in Fig. 3. The upper electrical conductors 8 are arranged above the height of the type of conductor 7 so that they do not exceed the height of the outer plates. In the lower part of the right hand side of the figure 7 and 7 of this example, the lower part of the electrical conductor 7 is arranged in such a way that it is not completely above the height of the outer plates. In the lower part of the figure 7 and 7 of the example, the lower part of the electrical conductor 7 may be placed in the lower left hand side of the outer plates.

In both embodiments, the housing 1 is placed in the positions shown in Figures 2 and 3. The liquid casting material 14 can now cool and thus solidify and harden. This ultimately results in a hard casting material 14 with the surfaces 16 and 17 shown in Figures 2 and 3. The casting material 14 is used to insulate the PCB 7 and the electrical components 8.

In the two versions described, the desired extrusion position is obtained by moving the housing 1 with the conveyor to a corresponding plane and then placing it in the position specified in Figure 2.

In both embodiments described in Figures 2 and 3, the above-mentioned free space is found inside the upper part 2 as a cable storage space 18 into which the electrical cable 10 can be inserted or removed through the cable opening 11.

The support strips 9 are shown in Figures 4 and 5. As shown in Figure 1, when the liquid casting material 14 is filled, the support strips 9 are completely surrounded by the casting material 14. This means that even after the casing 1 is tilted back from the filling position to the extrusion position, the support strips 9 remain covered with a thin layer of the casting material 14. Due to the surface tension of the liquid casting material 14, this results in an uneven thickness of the support strips 9 on the casting material 14 This in turn results in the height of the support strips 9 being lower and the radii of the support strips 9 being greater than or equal to the thickness of the support strips 9 on the casting material 14.

Claims (10)

1. A housing (1) for an electric body-care apparatus, in particular for a dental cleansing apparatus, wherein electric components (8) are accommodated in the housing interior and surrounded by a casting compound (14) that is filled into the housing, said components being connected to an electric cable (10) inserted through a cable opening (11) provided in the housing (1), characterized in that the cable opening (11) is positioned in an outer wall (12) of the housing (1) and is the only opening of the housing (1) to the electric components (8).
2. The housing (1) as claimed in claim 1, characterized in that, with the housing (1) in an upright position, the surface (16) of the casting compound (14) is approximately horizontal.
3. The housing (1) as claimed in claim 1, characterized in that, with the housing (1) in an upright position, the surface (17) of the casting compound (14) extends at an angle of inclination (b) to the horizontal.
4. The housing (1) as claimed in any one of the claims 1 to 3, characterized in that the interior of the housing (1) is provided with support ribs (9) which are coated at least partly with casting compound (14).
5. The housing (1) as claimed in any one of the claims 1 to 4, characterized in that the electric body-care apparatus contains a rechargeable storage battery, and that the electric components (8) form part of an electric charging device.
6. A method of manufacturing the housing (1) as claimed in any one of the claims 1 to 5, characterized in that the casting compound (14) is filled into the housing (1) through the cable opening (11) by means of a filling device (13).
7. The method as claimed in claim 6, characterized in that the housing (1) is positioned for filling with the casting compound (14) by means of a handling device which moves the housing into a filling position set at a filling angle (a) relative to the horizontal (FIG. 1).
8. The method as claimed in claim 6 or 7, characterized in that, to allow the casting compound (14) to harden, the housing (1) is moved by means of the handling device into an approximately horizontal position (FIG. 2).
9. The method as claimed in claim 6 or 7, characterized in that, to allow the casting compound (14) to harden, the housing (1) is moved by means of the handling device into a position set at an angle of inclination (b) relative to the horizontal (FIG. 3).
10. The method as claimed in any one of the claims 7 to 9, characterized in that the housing (1) is parked on a suitably sloping plane.