Hand-held appliance with improved coupling structure for a functional attachment of the appliance

Abstract

The invention relates to a coupling structure (8, 9, 10) for coupling a drive shaft (6) of a main body (2) of a hand-held appliance (1) to a driven part (7) of a releasable functional attachment (3) of the hand-held appliance (1). The coupling structure comprises a coupling bush (8), a coupling head (9) and a coupling spring (10). The coupling head (9) is axially fixed within the functional attachment (3), the coupling bush (8) is axially displaceable within the main body (2). The coupling spring (10) is housed in the main body (2) and urges displacement of the coupling bush (8) towards the coupling head (9), when the functional attachment (3) is attached to the main body (2). The coupling structure is compact, especially in the axial direction of the coupling structure, and especially within the functional attachment.

Claims

1. A hand-held appliance comprising a main body and a functional attachment, wherein: the hand-held appliance has an attached condition in which the functional attachment is releasably attached to the main body; the main body houses a motor and a drive shaft and comprises a hand-gripping area for manually holding the hand-held appliance; the functional attachment houses a driven part and a functional structure for performing a functionality of the hand-held appliance; the hand-held appliance comprises a coupling structure for coupling the drive shaft and the driven part for mutual co-rotation; a coupled condition of said coupling structure is defined as a condition, in which the hand-held appliance is in said attached condition, and in which the coupling structure couples the drive shaft and the driven part for mutual co-rotation; an uncoupled condition of said coupling structure is defined as a condition, in which the coupling structure does not couple the drive shaft and the driven part for mutual co-rotation; an operation condition of the hand-held appliance is defined as a condition, in which the coupling structure is in said coupled condition, and in which the motor drives the drive shaft, while at the same time the drive shaft drives the driven part in mutual co-rotation, while at the same time the driven part drives the functional structure of the functional attachment; the coupling structure comprises a coupling bush, a coupling head and a coupling spring, wherein the main body houses the coupling bush, and wherein the functional attachment houses the coupling head; the coupling bush and the drive shaft are coupled for mutual co-rotation, and the coupling head and the driven part are coupled for mutual co-rotation; said mutual co-rotation of the drive shaft and the driven part in said operation condition of the hand-held appliance is realized in that in said coupled condition of the coupling structure the coupling head is at least partly inserted via an axial end of the coupling bush into an interior space of the coupling bush, while in said interior space there is co-rotating coupling between the coupling bush and the coupling head; and in said attached condition of the hand-held appliance, the coupling spring urges relative displacement of one of the coupling head and the coupling bush towards the other of the coupling head and the coupling bush, so as to effectuate said coupled condition from said uncoupled condition when the motor drives the drive shaft, and so as to maintain said coupled condition when the motor drives the drive shaft; characterized in that: within the functional attachment the coupling head has an axially fixed position relative to the driven part, as seen along a rotation axis of the driven part; within the main body the coupling bush is axially displaceable relative to the drive shaft, as seen along a rotation axis of the drive shaft; and the main body houses the coupling spring, wherein the coupling spring urges displacement of the coupling bush relative to the drive shaft for said effectuating and said maintaining said coupled condition of the coupling structure when the motor drives the drive shaft in the attached condition of the hand-held appliance.

2. The hand-held appliance according to claim 1, wherein said axial displaceability of the coupling bush relative to the drive shaft is realized in that the coupling bush and the drive shaft are interconnected in mutual telescoping engagement.

3. The hand-held appliance according to claim 2, wherein, as seen in cross-sections transverse to the rotation axis of the drive shaft: a first circumference of an inner side of the coupling bush has a first non-circular shape, such as for example a first polygonal shape; a second circumference of an outer side of the drive shaft has a second non-circular shape, such as for example a second polygonal shape, wherein said second non-circular shape mates with said first non-circular shape for realizing said co-rotating coupling between the coupling bush and the drive shaft; and a third circumference of an outer side of the coupling head has a third non-circular shape, such as for example a third polygonal shape, wherein said third non-circular shape mates with said first non-circular shape for realizing said co-rotating coupling between the coupling bush and the coupling head.

4. The hand-held appliance according to claim 3, wherein said second non-circular shape is the same as said third non-circular shape.

5. The hand-held appliance according to claim 1, wherein the coupling head is an integrally manufactured part of the driven part.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The above mentioned aspects and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter by way of non-limiting examples only and with reference to the schematic figures in the enclosed drawing.

(2) FIG. 1 shows, in a perspective view, an example of an embodiment of a hand-held appliance according to the invention.

(3) FIG. 2 (Prior Art) shows, in cross-sectional perspective view, a hand-held appliance known from the prior art, in a condition in which the functional attachment of this known hand-held appliance has been released from the main body of this known hand-held appliance.

(4) FIG. 3A (Prior Art) separately shows, in a side view, the coupling structure of the known hand-held appliance of FIG. 2, wherein the coupling structure is in its coupled condition.

(5) FIG. 3B (Prior Art) shows the situation of FIG. 3A again, however this time in a cross-sectional view, which is partly a ghost view.

(6) FIG. 4A (Prior Art) shows the coupling structure of the known hand-held appliance of FIG. 2 again, in a cross-sectional partly-ghost view similar to the view of FIG. 3B, however wherein this time the view is more schematic than in FIG. 3B and wherein the coupling structure is not in coupled condition, but in uncoupled condition.

(7) FIG. 4B (Prior Art) shows the situation of FIG. 4A again, however this time in coupled condition of the coupling structure.

(8) FIG. 5A separately shows, in a side view, the coupling structure of the hand-held appliance according to the invention, shown in FIG. 1, wherein the coupling structure is in its coupled condition.

(9) FIG. 5B shows the situation of FIG. 5A again, however this time in a cross-sectional view, which is partly a ghost view.

(10) FIG. 6A shows the coupling structure of the hand-held appliance of FIG. 1 again, in a cross-sectional partly-ghost view similar to the view of FIG. 5B, however wherein this time the view is more schematic than in FIG. 5B and wherein the coupling structure is not in coupled condition, but in uncoupled condition.

(11) FIG. 6B shows the situation of FIG. 6A again, however this time in coupled condition of the coupling structure.

(12) FIG. 7A is a partly-ghost view onto a cross-sectional plane, which in FIG. 5B is indicated by the viewing-direction arrows VILA.

(13) FIG. 7B is a partly-ghost view onto a cross-sectional plane, which in FIG. 5B is indicated by the viewing-direction arrows VII-B.

DETAILED DESCRIPTION OF EMBODIMENTS

(14) The hand-held appliance as shown in FIGS. 1, 5A-5B, 6A-6B, 7A-7B has all the features of all of the abovementioned main and preferable embodiments of the invention. The reference signs used in FIGS. 1, 5A-5B, 6A-6B, 7A-7B are referring to the abovementioned parts and aspects of the invention, as well as to related parts and aspects, in the following manner. 1 hand-held appliance 2 main body 3 functional attachment 4 hand-gripping area 5 functional structure 6 drive shaft 6A drive-shaft main-body 6B drive-shaft adapter 7 driven part 8 coupling bush 9 coupling head 10 coupling spring 16 rotation axis of drive shaft 6 17 rotation axis of driven part 7 27 pivot pin for driven part 7

(15) Based on the above introductory description, including the brief description of the drawing figures, and based on the above-explained reference signs used in FIGS. 1, 5A-5B, 6A-6B, 7A-7B, the shown examples in FIGS. 1, 5A-5B, 6A-6B, 7A-7B are for the greatest part readily self-explanatory. The following extra explanations are given.

(16) FIG. 1 shows the hand-held appliance 1 in its attached condition, in which the functional attachment 3 is releasably attached to the main body 2. The shown hand-held appliance 1 is a shaving device, wherein the functional structure of the functional attachment 3 comprises two hair-cutting units 5. The coupling structure of the hand-held appliance 1 comprises the coupling bush 8, the coupling head 9 and the coupling spring 10.

(17) Reference is now made to FIGS. 5A-5B, 6A-6B, 7A-7B, while noting that FIGS. 6A-6B show the coupling structure 8, 9, 10 in a comparable, but more schematic cross-sectional view as compared to FIG. 5B.

(18) The driven part 7 is a gear wheel, wherein the coupling head 9 is an integrally manufactured part of the gear wheel. The driven part 7 is rotatable about the rotation axis 17 in that the driven part 7 is rotatable about the pivot pin 27 (shown in FIGS. 6A-6B), whose center line functions as the rotation axis 17.

(19) The drive shaft 6 comprises the drive-shaft main-body 6A and the drive-shaft adapter 6B, which is fixedly attached to the drive-shaft main-body 6A in a co-rotatable manner about the rotation axis 16.

(20) The axial displaceability of the coupling bush 8 relative to the drive shaft 6 is realized in that the coupling bush 8 and the drive shaft 6 are interconnected in mutual telescoping engagement.

(21) The coupling spring 10 is held in-between a flange of the drive-shaft adapter 6B and a flange of the coupling bush 8. Both the coupling bush 8 and the coupling spring 10 are coupled to the drive shaft 6 in a co-rotatable manner about the rotation axis 16. These co-rotatabilities are realized in that the circumference of the outer side of the drive-shaft adapter 6B has a polygonal shape, which mates with the polygonal shape of the circumference of the inner side of the coupling bush 8, as seen in cross-section transverse to the rotation axis 16 (see FIG. 5B in combination with FIG. 7B).

(22) The coupled condition of the coupling structure 8, 9, 10 requires that the functional attachment 2 is attached to the main body 3. The coupled condition of the coupling structure 8, 9, 10 additionally requires that the coupling head 9 is at least partly inserted via an axial end of the coupling bush 8 into an interior space of the coupling bush 8, while in said interior space there is co-rotating coupling between the coupling bush 8 and the coupling head 9. In the coupling structure 8, 9, 10 said co-rotating coupling in said interior space is realized in that the circumference of the outer side of the coupling head 9 has a polygonal shape, which mates with the polygonal shape of the circumference of the inner side of the coupling bush 8, as seen in cross-section transverse to the rotation axis 17 (see FIG. 5B in combination with FIG. 7A).

(23) In FIGS. 5A-5B the coupling structure 8, 9, 10 is in its coupled condition. Both in FIG. 6A and in FIG. 6B the functional attachment 2 is attached to the main body 3. The difference between FIG. 6A and FIG. 6B, however, is that in FIG. 6A the coupling structure 8, 9, 10 is in the uncoupled condition, while in FIG. 6B it is in the coupled condition. That is, in FIG. 6A the coupling head 9 does not yet extend into the interior space of the coupling bush 8 for co-rotating coupling between the coupling bush 8 and the coupling head 9, due to misalignment of the abovementioned mating polygonal shapes of the coupling head 9 and the coupling bush 8. In fact, FIG. 6A relates to a situation immediately after a user has attached the functional attachment 2 to the main body 3, after which the motor has not yet been started to drive the drive shaft 6. As soon as the user starts the motor, said misalignment will automatically be cancelled under influence of the coupling spring 10, which urges displacement of the coupling bush 8 towards the coupling head 9, so that the coupling head 9 will come to at least partly extend into the interior space of the coupling bush 8, whereby the coupled condition shown in FIG. 6B is obtained.

(24) Hence, it has now been made clear that the hand-held appliance 1 according to the invention differs from the known hand-held appliance 101 of FIGS. 2, 3A-3B, 4A-4B in that for the hand-held appliance 1 according to the invention: the coupling head 9 is axially fixed within the functional attachment 3 (instead of being axially displaceable within the functional attachment, as is the case for the coupling head 109 of the known hand-held appliance 101); the coupling bush 8 is axially displaceable within the main body 2 (instead of being axially fixed within the main body, as is the case for the coupling bush 108 of the known hand-held appliance 101); and the coupling spring 10 is housed in the main body 2 (instead of in the functional attachment, as is the case for the coupling spring 110 of the known hand-held appliance 101).

(25) While the invention has been described and illustrated in detail in the foregoing description and in the drawing figures, such description and illustration are to be considered exemplary and/or illustrative and not restrictive; the invention is not limited to the disclosed embodiments.

(26) Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. A single processor or other unit may fulfil the functions of several items recited in the claims. For the purpose of clarity and a concise description, features are disclosed herein as part of the same or separate embodiments, however, it will be appreciated that the scope of the invention may include embodiments having combinations of all or some of the features disclosed. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.