DE9309142U1 - Hand-held device for treating human skin, especially the scalp - Google Patents

Description

D&P Cosmetics ■ M:DP2103B

Adliswil / Switzerland

Hand-held device for treating human skin, especially the scalp

The invention relates to a hand-held device for treating human skin, in particular the scalp, according to the preamble of claim 1.

From DE-GM 71 39 371, a device for treating the scalp has become known, which is designed in the form of a bellows for vertical kneading or massaging of the scalp. The bellows is attached to a treatment cap for hyperemia of the scalp, whereby the treatment cap supports itself on struts that sit on the shoulders of a person undergoing scalp or scalp treatment. The bellows has a number of knobs on its lower part facing the scalp, which are intended to activate the scalp. By applying excess pressure, the bellows are unfolded and lowered towards the scalp and pressed onto it together with the knobs, and by pumping out the bellows, it contracts again so that the knobs are lifted off the scalp again. By rhythmically applying overpressure and underpressure, the knobs on the lower part of the bellows on the head side produce a massage or kneading effect in the area of the scalp or head. If necessary, medical and/or cosmetic preparations can be applied to the scalp or head skin while the bellows is folded up, i.e. lifted, and are then worked into the scalp or head skin by the kneading or massage effect.

The well-known device according to DE-GM 71 39 371 is neither practical nor up-to-date due to its bulky and cumbersome design.

Furthermore, this well-known device is cumbersome to operate and short-term, spontaneous "intermediate use" is practically impossible due to the cumbersome operation and also the complicated and bulky structure.

A hand-held device for treating human skin according to the preamble of claim 1 has become known from DE-PS 856 788. This known suction-pressure alternating massage device comprises a manually or electromechanically operated suction-pressure alternating pump with a housing to be held in the hand and a treatment head, the treatment head having an air-filled cavity which is delimited by a closed wall with the exception of a support side for resting on the skin. The support side to be placed on the skin has a sealing lip on the edge which closes off the cavity from the environment and the closed wall surrounding the air-filled cavity has an area which can be driven back and forth for the purpose of cyclically changing the volume of the cavity, with either manually or electromechanically operated drive elements being provided for the back and forth movement of the wall area.

The hand-held device known from DE-PS 856 788 for treating human skin is only suitable to a very limited extent for treatment or therapy purposes of the scalp or the head, since the sealing lip that closes off the cavity from the surroundings and runs around the edge when placed on the hair encloses it between itself and the scalp and presses it down, so that an airtight closure of the air-filled cavity placed on the skin to the outside due to the sealing lip between

and scalp is no longer guaranteed. However, it is precisely this largely airtight layer that is of crucial importance, since otherwise no pulsating overpressure and negative pressure conditions can be created inside the cavity, which would have the desired therapeutic effect on the scalp.

In contrast, the object of the present invention is to create a hand-held device for treating human skin, in particular the scalp, which is ergonomically handled and has an effective therapeutic and/or cosmetic effect on the scalp.

This object is achieved according to the invention by the features specified in claim 1.

According to the invention, the support side of the hand-held device intended for resting on the skin is covered by a treatment tool which has a cover wall for the support side and a plurality of prong-like projections protruding from the cover wall, at least one of which has an opening in its contact surface on the skin, which is in flow connection with the air-filled cavity.

Because the plurality of prong-like projections protrude from the cover wall, at least one of which has an opening in its contact surface on the scalp, which is in flow connection with the air-filled cavity, when the hand-held device according to the invention is used in such a way that it is guided through the hair like a comb or brush, with the projections resting on the skin with their contact surfaces, the hair is brushed aside or divided in a comb- or brush-like manner, so that the openings in the contact surfaces of the prong-like projections are in direct contact with the scalp.

skin and due to the flow connection between the respective openings and the air-filled cavity, the pulsating pressure oscillations, which are generated in the air-filled cavity, are transmitted to the scalp via the flow connection to the at least one contact surface resting on the scalp or the opening formed there. Since the hair on the head is divided like a comb or brush due to the prong-like design of the projections, the largely dense contact of the contact surfaces of the prong-like projections on the scalp is not obstructed or interrupted by entire strands of hair. At most a few individual hairs may remain between the contact surfaces of the prong-like projections and the scalp, but these few individual hairs are practically unable to impair the effective transmission of the pressure pulsations to the surface of the skin.

Due to the transmission of pressure pulsations via the flow connection between the air-filled cavity and the at least one opening, an effective suction/pressure massage of the scalp takes place. Since practically the entire scalp area is not treated in one go, as is the case with the subject matter of DE-GM 71 39 371, for example, since the hand-held device according to the invention is guided through the hair like a comb or brush, the hand-held device according to the invention can also be designed to be handy and small and thus ergonomically easy to handle.

Advantageous further developments of the invention emerge from the subclaims.

Preferably, the prong-like projections on the cover wall are arranged on at least two concentric circles. Due to the resulting uniform distribution of the prong-like projections on the surface of the

Cover wall results in both an even comb or brush effect and an even effect on the scalp or scalp.

Preferably, the projections on the outer circle have a closed contact surface and the projections on the inner circle have openings in their contact surfaces that are in flow connection with the air-filled cavity. If, furthermore, the projections on the outer circle preferably have a smaller diameter than the projections on the inner circle, more of the prong-like projections can be provided on the outer circle in a comb- or brush-like arrangement, so that the combing or brushing effect of the projections on the outer circle, i.e. the division of the head hair into individual strands, so that the projections on the inner circle or their openings can reach the scalp better, is optimized.

Furthermore, the projections located on the outer circle preferably have a slightly greater height extension relative to the cover wall than the projections located on the inner circle. The contact surfaces of the projections are therefore not in a flat plane, but on a slightly concave plane, which results in a better adaptation of the projections to the scalp, which lies in a convex plane.

Preferably, an air-permeable protective component for the cavity is located between the air-filled cavity and the cover wall. This ensures that no foreign bodies enter the cavity and that no one can reach into the cavity when the treatment tool is removed, which is also a preferred embodiment of the present invention. The air-permeable

The protective component is preferably a perforated sheet, i.e. a material that is easy to obtain, sufficiently permeable to air and yet sufficiently stable, which can easily be made into any desired shape.
5

The tine-like projections have a Shore hardness of about 30 to 70, preferably about 50. Shore hardnesses of less than 30 would make the tines too flexible/yielding, so that the desired combing effect would not occur and Shore hardnesses of more than 70 would make the tines unpleasantly hard.

The housing has a handle on the side opposite the support side. This allows the hand-held device according to the invention to be handled particularly ergonomically, since the hand holding the hand-held device does not have to be angled or turned unnaturally, so when the hand-held device is moved over the scalp, this movement corresponds to stroking the hair with the bare hand or a normal combing movement.

If this handle is essentially hemispherical, the hand-held device according to the invention can be gripped particularly easily and with little effort, since the hemispherical contour adapts to the palm of the hand.

The number of back and forth change cycles per second, which are applied to the wall area by the drive elements, is preferably more than three and less than 1000, preferably more than 10 and less than 100 and in particular more than 20 and less than 70. The cyclical change in the volume of the cavity and thus the frequency with which positive and negative pressure are alternately applied to the scalp to be treated is therefore, according to the invention, in particular in a range of 20 to 70 Hz.

Similar medical and cosmetic tests and examinations, as well as purely sensitive experience values from test subjects, have shown that in change cycles with frequencies below 3 Hz and above 1000 Hz, the mechanical effect on the scalp, i.e. the vibration massage that can be achieved with the hand-held device according to the invention, is perceived as unpleasant and pumping on the one hand, or no longer perceptible at all on the other. In the range from 10 Hz to 100 Hz, both sensory sensations and cosmetic and therapeutic effects can be detected, whereby the massage sensation on the one hand and the cosmetic or therapeutic effects on the other hand have been found to be particularly pleasant and effective in the range from 20 Hz to 70 Hz.

To adapt to specific types of treatment and locations, the frequency of the back and forth change cycles can be adjusted.

The frequency can be manually adjustable so that a person who uses the hand-held device according to the invention on their own body can set the frequency that they find most comfortable, or the frequency is program-controlled in such a way that, for example, starting at relatively low frequencies after a certain period of time, the frequencies slowly increase or vice versa.

If the treatment head with the air-filled cavity is detachably mounted on the housing, this ensures that the hygiene requirements to be observed when using one and the same device by several people are taken into account and, on the other hand, treatment heads that differ in shape and function can be exchanged with one another.

Preferably, the air-filled cavity is delimited by a rubber-elastic component with a closed wall. Due to the rubber-elastic design of the component defining the air-filled cavity, the at least one region that can be driven to move back and forth can be formed integrally on the component without complex bellows and/or valve parts.

If the rubber-elastic component is designed like a membrane that can be deflected on both sides, with the drive elements acting on the center of the membrane, the negative and positive pressures can be applied with a minimum of design effort.

The drive elements can have an electric motor, the output shaft of which generates the back and forth movement of the wall area via an eccentric device. Commercially available and robust, inexpensive components can therefore be used to provide a cost-effective and long-lasting drive.

Alternatively, the drive elements can have a piezoelectric actuator, which generates the back and forth movement of the wall area. This development of the present invention has the advantage that the piezoelectric actuator provides a silent and vibration-free drive.

If the drive elements are powered by batteries or accumulators arranged in the housing, the hand-held device according to the invention can also be used safely in wet rooms and on wet or damp hair.

Further details, aspects and advantages of the present invention will become apparent from the following description with reference to the drawing.

It shows:

Fig. 1 is a front view of a possible design of the hand-held device according to the invention;

Fig. 2 is a top view of the handheld device according to the invention from Fig. 1;

Fig. 3 is a side view of the hand-held device according to the invention from Fig. 1;

Fig. 4 is a cross-sectional view of the inventive

handheld device;
15

Fig. 5 is a perspective exploded view of the hand-held device according to the invention, the drive device in the housing not being shown; and
20

Fig. 6 shows schematically the circuit structure for supplying energy to the drive motor in the hand-held device according to the invention.

A hand-held device according to the invention, designated as a whole by 2 in the drawing, essentially has a housing 4 and a treatment head 6 arranged on it in the exemplary embodiment shown. As can best be seen from the sectional view in Fig. 4, the treatment head 6 has an air-filled cavity 8 which, with the exception of a support side 10, is delimited by a closed wall. The closed wall has an area which can be driven to move back and forth for the purpose of cyclically changing the volume of the cavity.

In the embodiment shown, this area is formed by a membrane 12 that can be deflected on both sides, whereby

IG

the deflection movements of the membrane 12 are generated by a drive device 14 to be explained below.

The membrane 12 is fixed to the lower open end of the housing 4 in the manner shown in Fig. 4: On the circumference, the membrane 12 merges into a sealing lip 16, which engages behind a step-shaped shoulder 18 at the lower open end of the housing 4. As a result, the cavity 8, with the exception of its support side 10, is formed with a closed wall by the membrane 12 and the sealing lip 16 formed on the membrane 12.

The treatment head 6 is attached to the housing 4 by an upper free peripheral edge 20 of the treatment head 6 being placed on the lower free end of the housing 4 in the area of the support side 10 there, as shown in the figures. The upper edge 20 of the treatment head 6 overlaps the sealing lip 16 in the area shown in Fig. 4, and the soft or rubber-elastic material of the membrane 12 and the sealing lip 16 formed in one piece thereon ensures that the edge 20 and thus the treatment head 6 are held securely on the housing 4 in the area of the support side 10 there, with elastic deformation of the sealing lip 16.

The treatment head 6 is designed as a treatment tool 22. The treatment tool 22 has a cover wall 24 which closes off the support side 10. For this purpose, the cover wall 24 extends into the upwardly projecting, circumferential edge 20. A plurality of prong-like projections 26 protrude from the cover wall 24. At least one of the projections 26 has an opening 28 at the end which is in flow connection with the air-filled cavity 8 via a channel 30.

The opening 28 opens into a support surface 32 of the respective prong-like projection 26.

The prong-like projections 26 have a Shore hardness of about 30 to 70, preferably about 50. The projections 26 are preferably formed in one piece on the treatment tool 22, which accordingly also has a Shore hardness of about 30 to 70, preferably about 50. The elasticity inherent in the treatment tool 22, also in the area of the edge 20 there, improves the plug connection between the sealing lip 16 and this edge 20, since the latter is slightly stretched and thus sits firmly on the sealing lip 16. As mentioned, the hardness of the projections 26 is in the range of about 30 to 70, preferably about 50. A Shore hardness of less than 30 would make the prongs too flexible/yielding, so that the desired combing effect would not occur, and Shore hardnesses of more than 70 would make the prongs unpleasantly hard.

The projections 26 are preferably arranged on at least two concentric circles on the cover wall 24.

As can best be seen from Fig. 4 and 5, the projections 36 located on the outer circle are provided with a closed support surface, i.e. they have no opening 28 and no channel 30 in their interior. The projections 38 located on the inner circle, on the other hand, have the open support surface 32, i.e. the end opening 28 and the channel 30 for the flow connection with the cavity 8.

Furthermore, the projections 36 located on the outer circle are smaller in diameter than the projections 38 located on the inner circle. This makes it possible to arrange a plurality of relatively close-together projections 36 on the outer circle. These close-together projections 36 then have a comb or brush effect, as will be explained in more detail below.

As can also be seen best in Fig. 4, the projections 36 located on the outer circle have a slightly greater height extension relative to the cover wall 24 than the projections 38 located on the inner circle. The individual support surfaces 32 of the projections 36 and 38 are therefore not located in a flat plane, but in a concavely curved plane, whereby the projections 36 and 38 adapt better to the curvature of the head and thus the scalp.

As can best be seen from Fig. 4 and 5, a protective component 40 is arranged between the cover wall 24 of the treatment tool 22 and the membrane 12 or the cavity 8. The protective component 40 is attached in such a way that it remains on the housing 4 even when the treatment tool 22 is removed, so that the membrane 12 cannot be accidentally or intentionally touched even when the treatment tool 22 is removed and is thus protected from damage. The protective component 40 is preferably a perforated sheet, which ensures sufficient protection against contact for the membrane 12 on the one hand and sufficient air permeability on the other.

The housing 4 itself has a handle 42 on the side opposite the support side 10. In the embodiment shown, the handle 42 is approximately hemispherical with grip recesses 44 and 46 on both sides. Due to the approximately hemispherical design of the handle 42 and the two grip recesses 44 and 46, the handle 42 lies ergonomically in the hand of a person using the handheld device. Furthermore, when using the handheld device 2 according to the invention, the hand guiding the handheld device 2 does not need to be unnaturally bent or twisted, since the movement when guiding the handheld device 2 over the scalp essentially corresponds to the movement

which a hand performs when stroking the hair or when brushing or combing.

The interior of the housing 4 is divided by a partition plate 48 into an upper space 50 and a lower space 52. The partition plate 48 represents the bottom surface of the hemisphere forming the handle 42. The lower space 52 is open at the end with the stepped shoulder 18 to which the sealing lip 16 of the membrane 12 is attached. The upper space 50 serves to accommodate the drive device 14, which essentially consists of an electric motor 54, an eccentric device 56 and an energy source 58. In the embodiment shown, the energy source 58 is formed by three 1.5 V batteries or accumulators 60, preferably those of size AA. The eccentric device 56 converts the uniform rotation of the output shaft of the motor 54 into a reciprocating movement, which is transmitted to the membrane 12 via a connecting rod 62. The connecting rod 62 passes through an opening 64 in the separating plate 48 and is fastened in the center of the membrane 12 with a suitable holding device 66. The rotary movement of the motor 54 is thus converted into an up and down movement of the connecting rod 62 and thus into an oscillating or up and down pumping movement of the membrane 12.

Due to this up and down pumping movement of the membrane 12, the volume of the cavity 8 is alternately increased or reduced and this cyclical increase and decrease in volume is transferred by means of the sealing lip 16 into the channels 30 of the projections 38 and thus to the openings 28 there due to the airtight design of the cavity 8.

Cyclic pressure pulsations are thus created in the area of the openings 28, which can have a direct effect on the underlying scalp. This effect is particularly improved by the fact that the contact surfaces of the projections 38 and

the openings 28 there are in a practically airtight relationship with the underlying scalp. This is achieved by the fact that when the hand-held device 2 or the treatment tool 22 is guided like a comb or brush, the prong-like projections 36 on the outer circle, which have a comparatively small diameter and are positioned close together like a brush, divide the hair into individual strands and thus the projections 38 that follow the projections 36 in the direction of movement of the hand-held device 2 can rest on the scalp with their contact surfaces 32 in a largely airtight manner. Since the hair is divided and pushed to the side by the projections 36 that run in the direction of movement, no strands of hair can get between the contact surfaces 32 of the projections 38 and the scalp and impair the largely airtight contact of these contact surfaces 32 on the scalp. At most, a few individual hairs can get between the contact surfaces 32 of the projections 38 and the scalp, but these few individual hairs cannot impair the largely airtight system.

The pulsating pressure oscillations generated by the membrane 12 cause alternating pressure and tension on the scalp in the area of the projections 38 or their contact surfaces 32, which leads to an intensive massage effect. The hand-held device 2 according to the invention can improve the blood flow to the scalp, which leads to better care for the entire scalp. Furthermore, cosmetic and/or therapeutic preparations, for example against hair loss, dandruff formation or the like, can be massaged into the scalp using the hand-held device 2 according to the invention. Due to the improved blood flow to the scalp that comes with the massage and due to the tapping massage that occurs due to the pulsating pressure fluctuations, such preparations are quickly worked into the scalp or absorbed by it.

here also the drive device 14, which causes the entire hand-held device 2 to vibrate at a low amplitude, depending on the speed of the motor 54, so that the treatment tool 22 or the projections 36 and 38 formed therein also vibrate at a low amplitude but relatively high frequency, which supports the massage effect, the removal of dead skin particles, etc.

The frequency of the back and forth movement cycles of the membrane 12 is preferably more than 3 and less than 1000, preferably more than 10 and less than 100 and in particular more than 20 and less than 70 Hz. It has been found that frequencies below 3 Hz and above 1000 Hz have no noticeable cosmetic or therapeutic effect and are sometimes even perceived as unpleasant. Cosmetic and therapeutic effects can already be detected in the range from 10 Hz to 100 Hz, but in the range from 20 Hz to 70 Hz the massage feeling on the one hand and the cosmetic/therapeutic effect on the other hand are particularly pleasant and effective.

The frequency with which the membrane 12 is driven by the motor 54 or the eccentric device 56 can be variable according to a preferred embodiment of the invention.

This frequency can either be set manually or it can be changed according to a specific program. Fig. 6 shows how the drive frequency for the membrane 12 can be set manually to two different values. Fig. 6 shows schematically the circuit structure for supplying energy to the motor 54 using the batteries 60, as well as the possibility of setting the speed of the motor 54 and thus the drive frequency of the membrane 12 to two different values using the eccentric device 56. According to Fig. 6, the motor 54 is connected to a negative connection 68 and a positive connection 70 of the energy source 58 via two lines 72 and 74. Here-

IS

in the line 72, the negative connection of a charging socket 76 is inserted and a two-stage switch 78 is inserted into the line 74. The energy source 58 consists of three individual batteries _60a, 60b and 60c, which are connected in series in a known manner. The connection between the batteries 60b and 60c is led via a line 80 to one pole 82a of the switch 78 and the other pole 82b of the switch 78 is led via a line 84 to the positive connection 70 of the energy source 58. Also connected to the positive connection 70 is the positive connection of the charging socket 76 via a line 86.

In one embodiment of the present invention, the three batteries 60a, 60b and 60c are 1.5 V batteries of size AA. The series connection of three such batteries shown in Fig. 6 thus gives a voltage of 4.5 V between the terminals 68 and 70. In the position of the switch 78 shown in Fig. 6, the motor 54 receives the full voltage of the energy source 58, since all three batteries 60a, 60b and 60c are in the energy supply circuit of the motor 54. If the switch 78 is switched so that contact is made with the pole 82a, the battery 60c is switched out of the energy supply circuit to the motor 54, so that the motor is only supplied with 3 V from the batteries 60a and 60b. Due to the lower operating voltage, the motor runs at a correspondingly lower speed and the membrane 12 is moved up and down via the eccentric device 56 at a correspondingly lower frequency.

If rechargeable batteries are used instead of the batteries 60a to 60c, they can be recharged via the charging socket 76, whereby the switch 78 is then in a zero position 82c, which is simultaneously the OFF position for the motor 54 and thus the handset 2.

Fig. 5 shows a perspective exploded view of the handheld device 2 according to the invention, whereby the batteries 60 of the energy source 58, the motor 54 and the eccentric device 56, as well as the associated holders and connecting lines have been omitted. The hemispherical handle 42 of the housing 4 can be seen with one of the grip recesses 46, as well as a cover 88 through which the batteries 60 of the energy source 58 are accessible for replacement purposes. Also shown is an opening 90 in the handle 42 through which the plug of a charger can be inserted into the charging socket 76. The opening 64 through which the connecting rod 62 runs from the eccentric device 56 to the membrane 12 is visible in the separating plate 48. At the lower free end of the housing 4, the circumferential sealing lip 16 is visible, which in the assembled state according to Fig. 4 is surrounded by the upper free edge 20 of the cover wall 24 of the treatment tool 22. Also clearly visible in Fig. 5 is the arrangement of the projections 36 and 38 on two concentric circles, with the projections 38 provided with the openings 28 lying on the inner circle and the projections 36 without openings 28 with a smaller diameter than the openings 38 lying on the outer circle.

The treatment tool 22 is - as already explained - detachably attached to the housing 4. This allows the treatment tool 22 to be easily cleaned after each use and/or a treatment tool 22 can be exchanged for another treatment tool, for example one with harder or softer projections 36 and 38 and/or a different arrangement of the projections 36 and 38.

The description of the present invention was based on a possible embodiment example. It is understood that within the scope of the present invention a large number of

Variations and modifications are conceivable without deviating from the essential core of the present invention. For example, a different shape of the housing 4 than that shown and described can be provided. It would also be conceivable to use a piezoelectric actuator to generate the up and down movements of the membrane 12 instead of the electric motor 54 and the eccentric device 56. The use of such a piezoelectric actuator would have the advantage that a noise- and vibration-free drive is available. The arrangement of the motor 54 and the batteries 60 in the illustration in Fig. 4 is also not mandatory; depending on the size and/or number of the components in question, other arrangements or installation positions are also possible or even necessary, e.g. an arrangement of the batteries 60 in a corresponding battery holder above the motor 54.

Claims (23)

D&P COSMETICS AG M:DP2103A Adliswil Switzerland Protection claims 1. Handheld device for treating human skin, in particular the scalp, with a hand-held housing (4) and a treatment head (6), wherein: the treatment head (6) has an air-filled cavity (8) which is delimited by a closed wall with the exception of a support side (10) for resting on the skin; the support side (10) has an edge-side sealing lip (16) which closes off the cavity (8) from the environment; the closed wall has at least one region (12) which can be driven to move back and forth for the purpose of cyclically changing the volume of the cavity (8); and Drive elements (14) are provided for the back and forth movement of the wall area (12), characterized in that the support side (10) is covered by a treatment tool (22) which has a cover wall (24) for the support side and a plurality of prong-like projections (26) protruding from the cover wall (24), at least one of which has an opening (28) in its support surface (32) on the skin, which is in flow connection with the air-filled cavity (8). 2. Hand tool according to claim 1, characterized in that the prong-like projections (26) on the cover wall (24) are arranged on at least two concentric circles. 3. Hand tool according to claim 2, characterized in that the prong-like projections (36) located on the outer circle have a closed support surface (32) and the projections (38) located on the inner circle have the openings (28) in their support surfaces (32) which are connected to the air-filled cavity (8) are in flow connection. 4. Hand tool according to claim 2 or 3, characterized in that the prong-like projections (36) located on the outer circle have a smaller diameter than the projections (38) located on the inner circle. 5. Hand tool according to one of claims 2 to 4, characterized in that the prong-like projections (36) located on the outer circle have a slightly greater height relative to the cover wall (24) than the projections (38) located on the inner circle. 6. Hand-held device according to one of claims 1 to 5, characterized in that an air-permeable protective component (40) for the cavity is arranged between the air-filled cavity (8) and the cover wall (24). 7. Hand tool according to claim 6, characterized in that the protective component (40) is a perforated plate. 8. Hand tool according to one of claims 1 to 7, characterized in that the prong-like projections (26) have a Shore hardness of about 30 to 70, preferably about 50. 9. Hand-held device according to one of claims 1 to 8, characterized in that the housing (4) has a handle (42) on the side opposite the support side (10). 10. Hand tool according to claim 9, characterized in that the handle (42) is substantially hemispherical. 11. Hand-held device according to one of claims 1 to 10, characterized in that the frequency of the reciprocating change cycles is greater than 3 Hz, preferably greater than 10 Hz and in particular greater than 20 Hz. 12. Hand-held device according to one of claims 1 to 10, characterized in that the frequency of the reciprocating change cycles is less than 1000 Hz, preferably less than 100 Hz and in particular less than 70 Hz. 13. Hand-held device according to one of claims 1 to 12, characterized characterized in that the frequency of the back and forth change cycles is variable. 14. Hand-held device according to claim 13, characterized in that the frequency of the reciprocating change cycles can be adjusted manually. 15. Hand-held device according to claim 13, characterized in that the frequency of the reciprocating change cycles can be changed under program control. 16. Hand-held device according to one of claims 1 to 15, characterized in that the treatment tool (22) is detachably arranged on the housing (4). 17. Hand-held device according to claim 16, characterized in that different treatment tools (22) can be arranged on the housing (4). 18. Hand-held device according to one of claims 1 to 17, characterized in that the air-filled cavity (8) is delimited by a rubber-elastic component with a closed wall. 19. Hand-held device according to claim 18, characterized in that the rubber-elastic component is designed as a membrane (12) that can be deflected on both sides. 20. Hand-held device according to claim 19, characterized in that the drive elements (14) are arranged at the center of the membrane (12) attack. 21. Hand tool according to one of claims 1 to 20, characterized in that the drive elements (14) have an electric motor (54), the output shaft of which generates the back and forth movement of the wall area via an eccentric device (56). 22. Hand-held device according to one of claims 1 to 20, characterized in that the drive elements (14) have a piezoelectric actuator which generates the back and forth movement of the wall region. 23. Hand-held device according to one of claims 1 to 22, characterized in that the power supply of the drive elements is via batteries and/or accumulators (60) which are arranged in the housing (4).