EP0406679A1

EP0406679A1 - Mixer for dye solutions and other mixtures for cosmetic use

Info

Publication number: EP0406679A1
Application number: EP90112206A
Authority: EP
Inventors: Vittorio Falchetti
Original assignee: Individual
Current assignee: Individual
Priority date: 1989-07-07
Filing date: 1990-06-27
Publication date: 1991-01-09
Also published as: IT8902935A0; IT1234310B

Abstract

This mixer for dye solutions and other mixtures for cosmetic use, including paste-like mixtures, consists of a removable cup (23) which has a semi-toroidal base and is fitted with a motorised unit (17) comprising gears defining an epicyclic motion, which provides a bristle-edged mixing beater (14), operating in the cup, with a combined movement of rotation (R) about its own axis and planetary revolution (P) about a vertical drive shaft (11), the axis of which coincides with that of the main roundness of the cup (23).

Description

This invention relates to a mixer for dye solutions and other mixtures for cosmetic use. In the cosmetics field, it is known to use many solutions, emulsions and mixtures in general, which can be in the liquid, creamy or pasty state. These substances require mechanical mixing to intimately and homogenously blend their components, or to form an overall complete solution. With regard to hair dyeing, generally done with a hydrogen peroxide-based solvent, rapid mixing is required because of the colour change which the dye undergoes with time. In beauty or hairdresser salons this is usually done in the small quantities required for a single client. The mixing is therefore done manually by an operator by mixing the substances in a common cup, using a brush or other equivalent means. In this respect, there are currently no machines for effecting this mixing. This is due to the difficulty of effecting mixing which is both complete and rapid, and which depends on the skill and professionality of the operator. This necessarily manual approach however involves the choice of either allowing the mixing to be done only by highly qualified persons or entrusting it to non-expert persons who are unable to obtain the optimum result. An object of the present invention is to provide a mixer for dye solutions and other mixtures for cosmetic use which gives both optimum and rapid results. A further object is to provide a mixer of ready use. A further object is to provide a versatile mixer. A further object is to provide a mixer which can be accompanied by a plurality of mixing containers able to be associated with a single drive unit.
A further object is to provide a mixer able to perfectly scrape the cup and prevent any concentrated residues remaining which might then be used in a damaging manner by forming colour streaks in the hair.
These and further objects will be apparent from the detailed description given hereinafter of a mixer for dye solutions and other mixtures for cosmetic use, including paste-like mixtures, as defined by the accompanying claims. The invention is illustrated by way of non-limiting example on the accompanying drawings in which:

Figure 1 is a plan view from above of an embodiment of a mixer with the cover of its mixing cup removed and showing a planetary gear unit which is independent of said cover;
Figure 2 is a section through the mixer on a longitudinal plane showing the planetary gears which in this case are not independent of the mixing cup cover;
Figures 3, 4 and 5 show a bristle-edged mixing beater from three mutually perpendicular directions.

With reference to said figures, a base 1 carries a structure 2 containing an electric motor 3 arranged with its axis 4 vertical and fixed by usual methods. The shaft 5 of said motor carries a first toothed pulley 6, which is connected to a second toothed pulley 7 by a usual toothed belt. The second pulley 7 is much larger than the first pulley 6, to obtain a considerable step-down ratio with the angular speed of the drive shaft 5. This second pulley is integral with a small gear wheel 8 which rotates together with the pulley 7 about a turning axis 9. The small gear wheel 8 engages with a much larger gear wheel 10 fixed onto a main exit shaft 11. This shaft is supported by two bushes 12 and 13 forming part of structures 2a and 2b respectively, which are fixed together by usual methods. The same method is used for supporting the pulley and gear wheel 7, 8. The function of the main exit shaft 11 is to rotate a mixing beater 14 in the direction R about its axis 15 while simultaneously causing it to orbit in the direction P about a further axis 16 coinciding with that of the main exit shaft 11. To achieve this, the main exit shaft 11 operates an epicyclic gear unit 17 (Figure 1) structured indicatively in the manner illustrated in Figure 2. A pinion 18 fixed onto the shaft 11 is relatively supported by an integral bush 19A at the base of a casing 19, and by a bush 20 provided axially on the hub of an internal gear 21 fixed into a fixed cover 22 which covers a fixed mixing cup 23. The cup can be provided with one or more handles 23A. The pinion 18 is therefore free to rotate relative to the gear 21 fixed to the cover 22 and provided with internal toothing. Said pinion however engages with a large gear wheel 24 rotating about a projecting pin 43, eccentric to the axis 16 and integral with the base of the casing 19. The large gear wheel 24 is coaxially integral with a further smaller gear wheel 25 engaged with the internal toothing of the fixed gear wheel 21. By this means, when the main exit shaft 11 rotates, it also rotates the casing 19 in accordance with the angular speed step-down ratio resulting from the engagement of the considered gear wheels. The large gear wheel 24 engages not only with the pinion 18 but also with a further gear wheel 26 having its axis parallel but eccentric to the axis 16. The gear wheel 26 is supported by two bushes 27 and 28 provided respectively on the base and on the cover 29 of the casing 19. This gear wheel is provided internally with an axial bore 30 of polygonal cross-section to receive the shaft 31 of the mixing beater 14. For this reason it acts as a secondary exit "shaft" driving the beater shaft 31, which is of the usual shape for its axial retention. As the shaft 31 is indirectly supported by the casing 19 rotating about the axis 16, it is subjected to orbiting motion about said axis in the direction P, while at the same time rotating about its own axis 15 in the direction R. A requirement for this operation is that the cover 22 must be fixed, ie is rigid with the structure 2, which itself is rigid with the base 1. To obtain this, two requirements must be satisfied, the first being that the cup 23 must be radially secured with respect to the axis 16; and the second being that the cup must not be able to rotate about the axis 16. The first requirement is satisfied by a centering edge 32, which forms the support base for the cup 23 and is removably inserted into a cylindrical projection 33 on the fixed structure 2. The second requirement is satisfied by torsionally locking the fixed cover 22 to the body of the cup 23 and, at the same time, by torsionally locking said cup to the fixed structure 2. For this purpose the fixed cover 22 is shaped with projections 22A to engage with conjugate projections 34 on the cup 23, and in addition the fixed cover 22 comprises a projection 35 to be retained tangentially by a stop 36 after that angular movement required for it to engage the structure 2. Viewing the illustrated mixer from above, this angular movement required for engagement is in the clockwise direction, and requires an aperture to be provided in the structure 2 to allow the projection 35 to be inserted through it. The aforegoing description defines the basic aspects of the invention. There are however certain other aspects which are important in terms of its operational optimization and its practical handling. These aspects can be expressed in a plurality of versions, which depend essentially on subjective design choices but which all fall within the defined scope of the invention. One of these aspects concerns the manner in which the casing 19 is fixed to the fixed cover 22. This fixing can be done by using conjugate polygonal sections, which can either allow the two parts to be axially separated or not, this latter by using for example a screw 36. In the first case, access to the interior of the cup 23 (required both when adding the components and when using them after mixing) requires firstly the removal of the cover 22, then the withdrawal of the pinion 18 via the end 37 by which it is fixed to the main shaft 11 to allow removal of the casing 19 carrying the mixing beater 14. In the second case, the removal of the casing 19 is effected by a single operation. At this point it is important to note that the casing cover 29, the fixed cup cover 22 and the internal gear 21 could be formed integrally in one piece, and consequently giving the other part of the casing 19 a circular shape rotating about the axis 16, with a single projecting support for the orbiting gear wheel 26, and with means for hindering any axial sliding so as to prevent removal from the fixed part 21, 22, 29. In this version, a topping-up hole 44 for correcting the mixed solution would have to be provided in a position which allows the added liquid to gain access to the interior of the cup 23. For safety reasons, the mixing beater 14 must operate only when the cup 23 is closed by the cover. Various means can be used to achieve this, for example activating the electric motor via a microswitch operated by the tangential movement of the projection 35 while the cup 23 is being closed by the cover 22, or by activating the electric motor 3 via an axial compressive movement of the cover 22 if restrained only rotatably. A further possible operating method is to operate a microswitch 38, connected to the electric motor 3, by a rod 41 moved by the stem of a specific pushbutton 39, the depressing movement of which is enabled by a plate 40 having a hole 42 which allows this depressing movement only when retained in a specific position by the presence of the radial projection 35, confirming the presence of the cover 22. If the electric motor is operated by simply depressing the fixed cover 22 under elastic return, the cover is retained for safety directly by the hand. If however the motor 3 is started by microswitches operated or operable as a consequence of turning the fixed cover 22, this angular movement is used to retain the fixed cover 22 on the cup 23 by the engagement of undercuts 34 by the conjugate projections 22A on the cover 22. This is achieved by usual bayonet-insertion by means of an axial movement followed by turning.
With reference to Figures 3, 4 and 5, the illustrated beater is in the form of a blade 14A with a slightly helical surface and edges provided with a plurality of short bristles 5 fixed by known methods. This blade has a semi-circular profile to be able to perfectly graze the entire toroidal surface of the cup 23. This perfection is achieved by the flexibility of the bristles, although a similar result could be obtained by a mixing blade with thin or laminar edges of soft material which could slide with conjugate contact against the annular profile of the cup.

Claims

1. A mixer for dye solutions and other mixtures for cosmetic use, including paste-like mixtures, characterised by a removable cup (23) which has a semi-toroidal base and is fitted with a unit (17) comprising gears (18, 24, 26, 21) defining an epicyclic motion, which provides a bristle-edged mixing beater (14), operating in the cup, with a combined movement of rotation (R) about its own axis (15) and planetary revolution (P) about a vertical drive shaft (11) the axis of which coincides with that of the main roundness of the cup (23).

2. A mixer as claimed in the preceding claim, characterised by a main vertical drive shaft (11) operated via a train of angular speed step-down ratios (6, 7; 8, 10) from an electric motor (3), the first stage (6, 7) of said train being preferably effected by using a toothed belt.

3. A mixer as claimed in the preceding claims, characterised by a releasable fixing between the parts involved in the epicyclic gear, such as to allow the connection between the hub of the internal gear (21) and the cover of the cup (23) to be broken and to also allow the connection between a central pinion (18) and the main drive shaft (11) to be broken, for the purpose of removing the casing (19) containing the epicyclic gear unit (17).

4. A mixer as claimed in the preceding claims, characterised by a mixing beater (14) fixed into a polygonal hole (30) in a planetary gear (26) by being inserted into it under the action of usual elastic axial retention means.

5. A mixer as claimed in the preceding claims, characterised by an electric motor (3) which can be activated only when the cup (23) has been correctly closed by its cover (22).

6. A mixer as claimed in the preceding claim, characterised by an electric motor (3) which is activated by a pushbutton (39) engagable with a rod (41) for operating a microswitch (38) only when a hole (42) in a plate (40) subjected to elastic return coincides with a stem of said pushbutton, said coincidence arising as a result of shifting by a radial projection (35) on the cover (22).

7. A mixer as claimed in the preceding claims, characterised in that the cover (22) and gear casing (19) are locked together axially by a screw (36) to allow the cup (23) to be uncovered and the mixing means (17, 14) to be extracted from it by a single operation.

8. A mixer as claimed in the preceding claims, characterised by an internal gear (21) integral with the casing cover (29) and with the cover (22) of the cup (23), such that a circular casing (19) of central axis (16) and containing an input pinion (18) which can be withdrawably fixed onto the main shaft (11) is unable to move axially but can rotate.

9. A mixer as claimed in the preceding claims, characterised by a mixing beater (14) of spatula shape with edges which can flexibly adapt to the toroidal profile of the cup (23) to continuous ly scrape the mixture contained therein.

10. A mixer as claimed in claim 9, characterised in that the edges of the spatula-shaped mixing beater (14A) are made flexible by a plurality of short bristles (S).