OA11889A

OA11889A - Toothbrush.

Info

Publication number: OA11889A
Application number: OA1200200027A
Authority: OA
Inventors: Udo Gotz; Martin Niebergall
Original assignee: Moser Elektrogerate Gmbh
Priority date: 1999-07-28
Filing date: 2000-07-27
Publication date: 2006-03-28
Also published as: EP1200008A1; BR0012803A; MXPA02000968A; TR200200580T2; DE50009595D1; OA11888A; EA200200083A1; AR027180A1; IS6214A; AU6438400A; JP2004500157A; EA003107B1; AU6829800A; HUP0201921A2; EA200200140A1; JP2003505142A; CN1364067A; EA003018B1; EP1200007A1; PL352038A1

Abstract

The invention relates to a toothbrush with a brush head (1) that is supported by a brush body (10) and that is provided with a bristle support (20) that receives the bristles (22). Said bristle support is rotatably mounted about an axis of rotation on a housing section (30) of a housing and is reversibly driven by an eccentric drive (50, 52). The brush body (10) is additionally mounted on the housing section (30) in such a manner that it can be pivoted within said section.

Description

118 8 9

Description

Toothbrush 5 The invention relates to a toothbrush with a toothbrush head supported by a toothbrushbody according to the preamble of claim 1.

Many types of eccentrically driven toothbrushes with different designs are commerciallyavailable. 10

Such toothbrushes typically hâve a toothbrush head that is supported by a toothbrushbody and interchangeably attached to an electrical hand tool. The toothbrush head has abristle carrier which receives the bristles and is pivotally supported for pivoting about apivot axis. The toothbrush head can be reversibly pivotally driven by an eccentric drive 15 and pivots alternatingly in two pivot directions with a specified pivot angle of, forexample, 130degrees.

In a commercially available and widely used toothbrush, the eccentric motion is producedby an eccentric gear arranged after the drive motor. The eccentric gear produces a 20 reversing stroke motion which is transferred to a drive pin. The drive pin pénétrâtes thetoothbrush body, wherein the angled end of the drive pin which extends in the axialdirection with respect to the pivot axis of the bristle carrier, engages in a correspondingbore located on the bristle carrier. The drive-pin bore is here radially offset ffom thepivot axis. In this way, the reversing stroke action of the lifting rod is transformed into a 25 reversing pivot motion of the bristle body. Such eccentric drives for toothbrushes aredescribed, for example, in the publications U.S. 5,617,601 or U.S. 5,524,312.

Another variation of an eccentric drive for toothbrushes is described in W0 96/37 164. Inthis variation, the circular rotary motion of the drive motor is transmitted directly to a 30 drive shaft which pénétrâtes the toothbrush body and has an angled end. The angled endengages with a corresponding guide channel located on the bristle carrier, thereby 2 1188 9 inducing a reversing pivot motion in the bristle carrier. This arrangement produces amechanically very simple and wear-resistant drive. This type of drive also requires verylittle space, so that the housing can hâve a slim and compact form.

Although a reversibly driven toothbrush of this type opérâtes reliably, it does hâveseveral disadvantages. In particular, the tooth cleaning ability of such a toothbrush stillneeds to be improved.

It is also known to improve the tooth cleaning ability by superimposing an additionalmotion on the rotation motion. For example, W0 96/31171 or DE 44 33 914 Al describetoothbrushes of this type with an eccentric drive, wherein the bristle carrier executes asort of pivoting motion.

It has been demonstrated, however, that such toothbrush is still unable to clean teethoptimally. Moreover, the toothbrush is mechanically complex.

Accordingly, the invention addresses the problem of improving a toothbrush of theaforedescribed type in such a way that it has an improved cleaning ability as well as asimple construction.

The stated problem is solved with a toothbrush of the aforedescribed type by thecharacterizing features of claim 1.

Advantageous embodiments of the invention are described in the characterizing featuresof the dépendent daims.

The invention relies on the concept of supporting the bristle carrier for axial displacementon the toothbrush head and to drive the bristle carrier with the eccentric drive reversiblybackward and forward along a linear path. This impresses on the bristle carrier anoscillating axial displacement motion which results in an excellent tooth cleaning ability. 3 1188 9

According to a first embodiment, the toothbrush head has at least one bearing channeladapted to engage with at least one corresponding bearing projection. This embodimentemploys limit stops that limit the linear travel path of the backward and forward motion(stroke) of the bristle carrier. 5

According to a second embodiment, the axial linear travel can be directly impressed onthe bristle carrier. For this purpose, a sliding block can be affixed in the axial direction inthe guide channel of the bristle carrier; alternatively, the sliding block can be moveable inthe axial direction between limit stops. The sliding block also has a drive-pin bore or a 10 guide channel, with the eccentric pin engaging in the guide channel. The bristle carrier issupported on the toothbrush head for axial displacement so as to positively follow thecorresponding motion of the eccentric pin in the axial direction between the tworeversing points. Accordingly, as described above, an axial displacement motion issuperimposed on the rotation motion. 15

According to additional embodiments, the superimposed axial displacement motion canalso be produced by providing the bristle carrier with at least one drive-pin channel whichis disposed along a circumferential segment of the bristle carrier and inclined in the axialdirection. The toothbrush head has a corresponding drive pin adapted to engage with the 20 drive-pin channel. A rotary motion is thereby positively transmitted to the bristle body toproduce an axial displacement motion, since the drive-pin channel has an axialcomponent. This arrangement provides an additional simple mechanical link guideproximate to the circumference of the bristle carrier. It is sufficient to provide a singledrive pin and correspondingly a single drive-pin channel, wherein the arrangement of 25 drive pin and drive-pin channel can be interchanged.

Alternatively, two diametrically opposed drive pins can be arranged on the toothbrushhead. This arrangement reduces the stress on the drive pins and on the channel, sincenow two link guides produce the axial force.

According to a fifth embodiment, the guide channel can be formed directly in the bristle 118 8 9 4 carrier. The eccentric pin directly engages the guide channel and thereby movesbackwards and forwards between a front and a rear reversing point. A force can therebybe transmitted via the sides of the guide channel extending in the axial direction, therebyreversibly driving the bristle carrier.

This embodiment opérâtes very quiet due to the small number of moveable parts and issuited in particular for high-frequency applications, i.e., so-called fast-runningtoothbrushes which are commonly referred to as "ultrasonic" toothbrushes. The eccentricshaft of such toothbrushes rotâtes with the rotation speed in the range between 15,000and 25,000 révolutions per minute. At such high rotation speeds, the components aresubjected to particularly high stress which is amplified by the continuous reversai of therotation direction of the toothbrush body. It is therefore important to construct thetoothbrush in the simplest possible fashion, as implemented to a great extent by theaforedescribed measures.

The proposed construction does not require additional constructive measures to impresson the bristle carrier the axial displacement motion in addition to the oscillatory pivotingmotion. This combination results in the excellent tooth cleaning ability mentioned above.For this purpose, the length of the guide channel in the axial direction is smaller than thetravel path between the front and the rear reversing points of the eccentric pin.

The travel of the eccentric pin is bounded by the limited length of the guide channel inthe axial direction. The bristle carrier is supported for axial displacement on thetoothbrush head so as to positively execute in the axial direction the correspondingmotion of the eccentric pin between the two reversing points. This causes an axialdisplacement motion to be superimposed on the rotation motion.

According to a sixth embodiment, a sliding block is afïïxed in the axial direction on thebristle carrier. The sliding block has a guide channel adapted to engage with the eccentricpin which can move backward and forward in the axial direction between a front and arear reversing point. 5 118 8 9

According to a seventh embodiment, the sliding block is supported in the guide channelfor axial displacement. The sliding block has a drive-pin bore adapted to engage with theeccentric pin. The eccentric pin thereby guides the sliding block backward and forwardbetween a front and a rear reversing points inside the guide channel integrated in thebristle carrier.

Ail embodiments with a sliding block hâve in common that the sliding block and thecorresponding recess or guide channel, respectively, disposed on the bristle carrier areformed so as to enable a rotation or pivoting motion of the sliding block which opposesthe pivot motion of the bristle body, so that the eccentric pin engaging with the recess orguide channel is not subjected to bending stress.

The sliding blocks typically hâve a cylindrical shape, thereby providing a reliable supportin the recess and guide channel, respectively. According to a preferred embodiment, thesliding block can also hâve a spherical shape. This embodiment advantageouslyminimizes the friction forces produced between the sliding block and the recess or theguide channel, respectively.

The invention will now be described in more detail with reference to the embodimentsillustrated in the drawings. It is shown in:

Fig. 1 a cross-sectional view of a drive according to a first embodiment;

Fig. 2 an enlarged cross-sectional view (detail) of a drive according to Fig. 1;

Fig. 3 an enlarged cross-sectional view of a drive according to a second embodiment;

Fig. 4 an enlarged cross-sectional view of a drive according to a third embodiment;

Fig. 5 an enlarged cross-sectional view of a drive according to a fourth embodiment; and 6 1188 9

Fig. 6 an enlarged cross-sectional view of a drive according to a fifth embodiment.

The first embodiment of a toothbrush 1 is depicted in Fig. 1. A toothbrush head 12 forms a component of a toothbrush body 10 which can beinterchangeably connected to a handle portion 60. A bearing journal 16 which engageswith a corresponding bearing bore 26 of a bristle carrier 20 is disposed on the toothbrushhead 12. The bearing journal 16 therefore represents the rotary/pivot bearing for thebristle carrier 20.

The toothbrush head 12 also includes a circumferential bearing channel 14 adapted toengage with a corresponding bearing projection 24 of the bristle carrier 20. As a resuit,the axial travel path of the bristle carrier 20 with respect to the toothbrush head 12 islimited, which prevents the bristle carrier 20 from becoming detached. The bristle carrier20 includes a recess 28 extending in the axial direction, with a sliding block 30 having aguide channel 32 being inserted in the recess 28. The axial position of the sliding block30 is defined with respect to the recess 28 and the bristle carrier 20, respectively.

An eccentric pin 52 of a drive shaft 50 engages in the guide channel 32, which in thegiven example is in form of a bore. However, the guide channel 32 can also extend in theaxial direction. The drive shaft 50 is rotatably driven by a motor 40.

Accordingly, the bristle carrier 20 moves in the following fashion:

As seen more particularly from the enlarged diagram X of Fig. 1, the eccentric pin 52 inthe exemplary cross-sectional view is located at the left reversing point. When therotation starts, the position of the eccentric pin 52 moves to the right, until the eccentricpin 52 reaches a right reversing point.

The toothbrush head 20 thereby executes the pivoting motion indicated in the top rightcorner of the partial view, namely starting from the left end position indicated by thesolid line to the right end position indicated by the dashed line. When the pivoting 7 118 8 9 motion continues, the eccentric pin 52 returns to its initial position, with the toothbrushbody 20 executing a pivoting motion in the opposite direction.

The motion can only be performed reliably if the eccentric pin 52 is laterally guided witha relatively small clearance, so that the pivotai motion can be transformed substantiallywithout play. In addition, the sliding block 30 has to be supported in the recess 28 so asto be able to pivot about its longitudinal axis in the opposite direction of the rotation ofthe bristle carrier 20 to compensate for the motion of the bristle carrier 20, in order toprevent bending stress on the engaging eccentric pin 52. The sliding block 30 and therecess 28 hâve a matching circular cross-section to enable an essentially play-freecompensating motion without noticeable friction. It should also be noted that the lengthof the eccentric pin 52 is selected so that it always engages the sliding block 30 regardlessof the actual position of the sliding block 30.

With this simple mechanical arrangement, the continuous rotary motion of the drive shaft50 can be transformed into a reversing rotary motion (pivoting motion).

Fig. 2 is an enlarged view of the toothbrush according to Fig. 1. The following detailedfeatures can be seen in Fig. 2:

An upper end of a toothbrush body 210 has a toothbrush head 212 with a bearing journal216. The bearing journal 216 receives a bristle carrier 220 on a bearing bore 226.

The bristle carrier 220 is supported for axial displacement relative to the toothbrush head212. A circumferential bearing projection 224 engages with a bearing channel 214 on thetoothbrush head 212, wherein the bearing channel 214 is constructed so that the bristlecarrier 220 can travel between a forward axial position, shown in Fig. 2 on the left, and arearward axial position, shown in Fig. 2 on the right. The maximum travel path isreferred to as "stroke."

The bristle carrier 220 includes an axial guide channel 228 in which a sliding block 230 is 8 1188 9 inserted. The sliding block 230 is fixed in the axial direction relative to the bristle carrier220. In addition, the sliding block 230 has a drive-pin bore 232 adapted to engage withan eccentric pin 52 of a drive shaft 50. 5 Since the eccentric pin 52 is positively coupled with the bristle carrier 220 in the axialdirection via the sliding block 230, the bristle carrier 220 executes an axial linear motionwhich is superimposed on the rotation motion. This high-frequency pulsating motion inthe axial direction significantly improves the cleaning resuit. This observation cantherefore be implemented by simple mechanical means, as discussed with reference to the 10 aforedescribed embodiment.

Fig. 3 shows a toothbrush 300 in which an axial linear motion of a bristle carrier 320 isalso implemented by a positive coupling. , 15 Again, a toothbrush body 310 with a toothbrush head 312 and a bearing journal 316 isprovided. The bearing journal 316 receives the bristle carrier 320 for axial displacementin a bearing bore 326.

The bristle carrier 320 includes an axial guide channel 328 in which an axially moveable 20 sliding block 330 is inserted. The sliding block 330 has a drive-pin bore 332 adapted toengage with an eccentric pin 52 of a drive shaft 50.

In addition, two diametrically opposed, radially inwardly-facing drive pins 314 areinserted on the toothbrush head 312. The drive pins 314 engage with two corresponding 25 drive channels 324 disposed along a circumferential segment of the bristle carrier 320.The drive pins 314 are slightly inclined in the axial direction, so that a rotation motion ofthe bristle carrier 320 causes a positively coupled axial displacement motion.

The toothbrush 400 depicted in Fig. 4 is implemented essentially identical to the 30 aforedescribed embodiments. 9 1188 9

Again, a toothbrush body 410 has a toothbrush head 412 with a bearing journal 416. Thebristle carrier 420 is supported for longitudinal displacement on the bearing journal 416by a bearing bore 426. 5 The bristle carrier 420 has an axial guide channel 428 in which a sliding block 430 issupported for axial displacement. The sliding block 430 has a drive-pin bore 432 adaptedto engage with an eccentric pin 52 of a drive shaft 50.

So far, this embodiment is identical to the embodiment described with reference to Fig. 3, 10 except for the fact that only one drive pin 414 is provided which coopérâtes with a drivechannel 424. The axial linear motion is produced by having a drive channel 424 which isslightly inclined in the axial direction, thereby defming the axial stroke of the bristlecarrier 420. 15 The only différence between the embodiment of a toothbrush 500 depicted in Fig. 5 andthe previously described embodiments is that a sliding block 530 has a spherical shape.The sliding block 53 has a drive-pin bore 532 adapted to engage with an eccentric pin 52of a drive shaft 50. 20 The sliding block is guided for axial displacement in an axial guide channel 528 of a bristle carrier 520. The bristle carrier 520 has a bearing bore 526 which guides the bristlecarrier 520 on a bearing journal 516 for longitudinal displacement. The bearing journal516 is attached to a toothbrush head 512 of a toothbrush body 510. 25 A drive pin 514 is disposed on the toothbrush head 512, wherein the drive pin 514 coopérâtes with a corresponding drive channel 524 in such a way that a pivoting motionof the bristle body 520 causes a positively-coupled axial stroke of the bristle body 520.

The embodiment of the toothbrush 600 illustrated in Fig. 6 is essentially identical to the 30 embodiments depicted in Figs. 4 and 5. 10 1188 9

Again, a toothbrush body 610 with a toothbrush head 612 is illustrated, wherein thetoothbrush head 612 has a bearing journal 616. The bristle carrier 620 is supported forlongitudinal displacement on the bearing journal 616 via a bearing bore 626. 5 As shown in detail in Figs. 4 and 5, a drive pin 614 coopérâtes with a drive channel 624which is slightly inclined in the axial direction. This produces the axial stroke of thebristle carrier 620.

So far, the basic construction of the illustrated embodiment of the toothbrush is identical 10 to that described with reference to the embodiments of Figs. 4 and 5, except for the factthat in the embodiment of a toothbrush 600 depicted in Fig. 6 the guide channel 628 isformed directly in the bristle carrier 620.

The eccentric pin 52 which can be set in rotation by the drive shaft 50 which is in turn 15 driven by a motor, engages directly with the guide channel 628. The motor drive operating on the drive shaft 50 causes the eccentric pin 52 to move freely backward andforward in the guide channel 628 between a front and a rear reversing point. Theeccentric pin 52 transmits a force to the bristle carrier 620 via the sides of the guidechannel 628 which extend in the axial direction. To eliminate bending stress in the 20 eccentric pin 52 which engages in the guide channel 628, the guide channel 628 has acavity 634 extending inwardly in the radial direction, with the cavity 634 receiving thefree end of the eccentric pin 52, with a space being formed between the free end and theinner wall of the cavity 634. 11 1188 9

List of référencé numerals 1 toothbrush 10 toothbrush body 5 12 toothbrush head 14 bearing channel 16 bearing journal 20 bristle carrier 24 bearing projection 10 26 bearing bore 28 recess 30 sliding block 32 guide channel 40 motor 15 50 drive shaft 52 eccentric pin 60 handle 200 toothbrush 20 210 toothbrush body 212 toothbrush head 214 bearing channel 216 bearing journal 220 bristle carrier 25 224 bearing projection 226 bearing bore 228 guide channel 230 sliding block 232 drive-pin bore 300 toothbrush 30 12 118 8 9 310 toothbrush body 312 toothbrush head 314 drive pin 316 bearing journal 320 bristle carrier 324 drive-pin channel326 bearing bore 328 guide channel 330 sliding block 332 drive-pin bore 400 toothbrush 410 toothbrush body 412 toothbrush head 414 drive pin 416 bearing journal 420 bristle carrier 424 drive-pin channel426 bearing bore 428 guide channel 430 sliding block 432 drive-pin bore 500 toothbrush 510 toothbrush body 512 toothbrush head 514 drive pin 516 bearing journal 520 bristle carrier 524 drive-pin channel526 bearing bore 13 118 8 9 guide channelsliding blockdrive-pin bore toothbrushtoothbrush bodytoothbrush headdrive pinbearing journalbristle carrierdrive-pin channelbearing boreguide channelcavity

Claims

14 - 1188 9 Amended Claims

1. Toothbrush with a toothbrush head (312; 412; 512; 612) supported by atoothbrush body (310; 410; 510; 610), the toothbrush head (312; 412; 512; 612)comprising: a bristle carrying bristle carrier (320; 420; 520; 620), the bristle carrier (20; 220; 320; 420; 520; 620) rotatably supported for rotating about a rotation axis andadapted to be reversibly rotatably driven by an eccentric drive (50, 52), wherein the eccentric drive has a drive shaft (50) rotating in one direction and arrangedperpendicular to the rotation axis (R) of the bristle carrier (320; 420; 520; 620) andcentrally extending through the toothbrush body (310; 410; 510; 610), with an endface of the drive shaft (50) having an eccentric pin (52), wherein the bristle carrier (320; 420; 520; 620) has a guide bore or a guide channel(328; 428; 528; 628) extending in the axial direction, with the eccentric pin (52)guided in the guide bore or guide channel, characterized in that the bristle carrier (320; 420; 520; 620) is supported on the toothbrush head(312; 412; 512; 612) for movement in the axial direction and adapted to be reversiblydriven by the eccentric drive (40, 50, 52) so as to move backward and forward along alinear path, that the bristle carrier (320; 420; 520; 620) has at least one drive pin channel(324; 424; 524; 624) which is disposed along a circumferential segment of the bristlecarrier (320; 420; 520; 620) and inclined in the axial direction, and that the at least one drive pin (314; 414; 514; 614) which is guided in the drivepin channel (324; 424; 524; 624) , is disposed on the toothbrush head (312; 412; 512;614).

2. The toothbrush according to claim 1, characterized in that the two diametrically opposed guide pins (314) are disposed on thetoothbrush head (310). - 15 - 118 8 9

3. The toothbrush according to claim 1 or 2, characterized in that the guide channel (628) is formed directly on the bristle carrier(620).

4. The toothbrush according to claim 1 or 2, characterized in that the guide channel is part of a sliding block which is axiallyaffixed to the bristle carrier.

5. The toothbrush according to claim 1 or 2, characterized in that a sliding block (330; 430; 530) is supported for axial displacement in theguide channel (328; 428; 528), and that sliding block (330; 430; 530) has a drive-pin bore (332; 432; 532) adaptedto engage with the eccentric pin (52).

6. The toothbrush according to claim 4 or 5, characterized in that the sliding block (330; 430) has a cylindrical shape.

7. The toothbrush according to claim 4 or 5, characterized in that the sliding block (530) has a spherical shape.

8. Toothbrush with a toothbrush head (12; 212) supported by a toothbrush body(10; 210), the toothbrush head (12; 212) comprising: a bristle carrying bristle carrier (20; 220), the bristle carrier (20; 220) rotatablysupported for rotating about a rotation axis (R) and adapted to be reversibly rotatablydriven by an eccentric drive (40, 50, 52), wherein the eccentric drive has a drive shaft (50) rotating in one direction and arrangedperpendicular to the rotation axis (R) of the bristle carrier (20; 220) and centrallyextending through the toothbrush body (10; 210), with an end face of the drive shaft(50) having an eccentric pin (52), wherein the bristle carrier (20; 220) has a guide bore or a guide channel (28; 228)extending in the axial direction, with the eccentric pin (52) guided in the guide bore orguide channel, - 16 - 1188 9 characterized in that the bristle carrier (20; 220) is supported on the toothbrush head (12; 212) formovement in the axial direction and adapted to be reversibly driven by the eccentricdrive (40, 50, 52) so as to move backward and forward along a linear path, 5 - that the eccentric pin (52) engages in a drive-pin bore (32; 232) or a guide channel (28; 228), and is mounted axially fixed in the drive-pin bore (32; 232) or isaxially moveable in the guide channel (28; 228) between limit stops.

9. The toothbrush according to claim 8, thereby characterized, that the toothbrush head (12; 212) has at least one bearing 10 channel (14; 214) adapted to engage with at least one corresponding bearing projection (24; 224) which limits the backward and forward linear motion (stroke) ofthe bristle carrier (20; 220).

10. The toothbrush according to claim 8 or 9,characterized in 15 that a sliding block (30; 230) is provided which includes a drive-pin bore (32; 232) or a guide channel adapted to engage with the eccentric pin (52), and that the sliding block (30; 230) is axially affixed in the guide channel (28; 228)or axially moveable therein between limit stops.

11. The toothbrush according to claim 10, 20 characterized in that the sliding block (130; 230; 330; 430) has a cylindrical shape.

12. The toothbrush according to claim 10, characterized in that the sliding block (530) has a spherical shape.