MXPA98010570A - Device of dental hygiene with part of dental hygiene replacement - Google Patents

Abstract

The present invention relates to a dental hygiene device with a part of dental hygiene with replaceable dental hygiene. In the case of a dental hygiene device, for example, a toothbrush, having a handle, a head and a part of dental hygiene insertable as a fixation in a depression thereof, the part of dental hygiene can be expelled by means of a piece of resilient pressure located at the back of the head and which acts when pressure is exerted on the back part of the dental hygiene part. In order to provide a sealed finish on the back and for example a manipulation, the head has, at the rear, an opening closed by the pressure piece and in which the dental hygiene part and the pressure piece are coupled. It is constructed as a resilient plastic disc and is fixed in a sealing manner with its circumferential edge on the wall of the opening.

Description

DENTAL HYGIENE DEVICE WITH REPLACEABLE DENTAL HYGIENE PART Description of the invention The invention is concerned with a dental hygiene device or oral hygiene with a handle, a head and a part of dental hygiene insertable as a fastening in a depression of the head and which by means of a resilient pressure piece on the back of the head acting by pressing on the back part of the dental hygiene part can be expelled. Dental hygiene devices of the aforementioned type are used in particular as brushes for the teeth, so that the latter will only be referred to hereinafter. However, they also cover devices which are used exclusively for the massage of the gums or for the care of interdental spaces. Brushes for teeth are required much more frequently than other types of brushes. The reason is frequent use, necessary for proper oral hygiene (up to three times a day) and the rapid wear resulting from this. In addition, even in the case of relatively limited wear which would be acceptable with other brushes, a toothbrush has to be replaced to always ensure optimum effectiveness. REF: 29011 Due to the high consumption of brushes for teeth, approximately 150 million per year in Germany, there is an increased problem of waste and protection of resources, because the fraction of material that becomes unusable due to wear is extremely small compared to the total material and the total material discarded, even in the case of a 100% recycling, can not be processed to the same product, because the recycled material no longer meets the high quality requirements that are vital, for example, for the material of the bristles of a toothbrush. Even if the known brushes with a replaceable brush part made it fundamentally possible to only replace the part of the brush after the wear, this problem has not been until now in the front and also the case of the standard brushes, such as cleaning brushes, brushes for the body, cosmetic brushes, etc., is relatively unimportant, because the period of use is much longer and the ratio of unusable and still usable material are not in the same disproportion as with toothbrushes. Finally, in relation to toothbrushes, the special characteristic must be taken into account that they must be correctly usable by humans of all age classes and all levels of education, in such a way that replacement of the Brush part should be possible in a very simple way and with a limited force expense, while at the same time the parts are joined properly safely. In the present there are essentially two systems in the market. In the case of the so-called replacement head brushes (or replaceable head) (EP 0,199,849 Bl, DE 94 20 405 Ul) the entire head with bristles is detachably fixed to the handle. The fixing means are located on the handle substantially transversely to its longitudinal axis and on a flange of the head and are brought into engagement by the assembly or assembly of the head and the handle in the axial longitudinal direction. Conversely, the two parts can be separated by pulling them in the longitudinal axial direction. These replaceable head brushes are satisfactory from the point of view of use and hygiene. In addition, the plastic fraction of the head, which becomes waste when the bristles wear out, is still considerable. The additional disadvantages arise that the fixing means are located in the transition area between the head and the handle, that is, in an area where the greatest bending forces act during use. Nevertheless, it is precisely in this area that the toothbrush is weakened by the construction measures for the fixing means. This is particularly serious because, for reasons of use, between the handle and the head it is desirable to have a slender and optionally resilient neck, which can not be implemented with such replaceable head brushes. Therefore, either replaceable head brushes have been proposed, in which the head is fixed with the slender neck on the thicker handle. Thus, although the advantage of use is substantially maintained, this is obtained at the cost of a greater amount of plastic waste. In addition, the risk also arises with all replaceable head brushes which, in the case of incorrect fixation or a failure of the fixation system during use, can cause serious injuries in the oral cavity. With other known systems, to which the toothbrush belongs according to the preamble of claim 1, the bristles are fixed to a support in the form of a thin plate and the part of the brush is fixed in a replaceable manner in the frame or frame-like head (DE 30 38 895, 37 24 640). The support is provided on its circumferential surface with flange-like seals and the frame has corresponding channel-like depressions. At its rear part, the support also has a needle or pin, which engages in a hole in the bottom of the frame and forms an exposed pressure surface on the back of the head. The support is fixed on the head and can be expelled by pressing on the needle. The fraction of plastic to be replaced in the case of wear of the bristle is reduced to a minimum and the replaceable brush parts can be manufactured in a non-expensive manner due to the small amount of material used. However, problems of hygiene and construction arise compared to replaceable head brushes. In the space necessarily present between the support and the jaw of the frame, which dries only inadequately, there is a deposition of garbage and accumulation of bacteria. This applies to a greater or lesser extent for the entire space between the head and the support. Thus, on its side of the bristles, the support is provided with an elastic circumferential boundary (DE 37 24 640 C2), the rear part of which is sealingly engaged against the front face of the jaw of the frame. This presupposes corresponding tensile forces which pull the support to the frame and consequently high corresponding clamping forces. In turn, this makes insertion and ejection of the brush part more difficult. As the fixing is carried out by the self-closing, the fixing means must be of a correspondingly large me nature, which requires a considerable wall thickness on the head. Even more complicated is a construction (DE 296 00 398 Ul), in which elastic flat seals are provided on all the sealing faces between the support and the frame, which by means of a correspondingly high pre-tension simultaneously retains the part of the brush . The pre-tension must be completely absorbed by the jaw of the frame, which necessarily widens after a short time and reliable retention of the brush part is no longer ensured. Other proposals (DE 91 09 625 Ul, DE 44 34 617 Al), which provide attachment ridges in portion on the circumference of the support, lead to a corresponding reduction in the sealing of the space, because the fixing and hollow edges they are located on the sealing surfaces and very close tolerances must be observed in order, on the one hand, to ensure a press fit of the sealing surfaces and, on the other hand, a reliable fixing. It is hardly possible to obtain such tolerances with injection molded parts and the inexpensive plastics required for the head and the handle. further, the jaw of the frame is constantly under elastic prestress due to the fixing forces. Since the plastics are not resistant to under-tensioning (cold flow), there is a very rapid decrease in the tensile force of the frame jaw, so that the space between the jaw and the support is widened and increased the infiltration of dirt and bacteria. Since the fatigue of the plastic and the resulting increase in tolerances can be noticed only by the user, he can only notice the failure of the fixing means when cleaning or brushing the teeth. If the part of the brush is separated during use, it can once again lead to injury to the oral cavity and the gums. A very stable and durable connection of the part of the brush and the head takes place in a known toothbrush (DE 41 04 314 Al) in which on the back of the support two mutually V-shaped flanges are formed, which pass over the entire length of the support. They fit into a slit in the opening of the head outward, in a V-shaped manner and which also passes over the entire length on its longitudinal axis. During insertion the ridges must be deformed inwardly and towards each other to such an extent that they can pass through the narrower cross-section of the V-shaped groove or groove and then expand into the groove. Thus, the elastically deformed portions of the fixing connection are located in the replacement part, where the fatigue of the material is less important. The forces of deformation on the edges required to produce and separate the fixing joint are so high that the part of the brush can only be pressed or leveled with the help of specially adapted tools. The need for such special tools not only leads to correspondingly high system costs for the consumer, but is detrimental to a practical acceptance of the system by the market. This also applies because it is not possible to satisfy a requirement to avoid injury, ie, a smooth shape of the back of the brush. In addition, this toothbrush is also completely unacceptable for reasons of hygiene, because the slit or groove and ridges form severe cracks, in which dirt, toothpaste residues and bacteria can deposit. The same applies to another known construction (US Pat. No. 4,543,679) with a needle or expansion pin on the support, which engages in a V-shaped hole on the back of the head. In all constructions with a needle exposed on the back as the pressure piece, the already described problem of dirt penetration and the accumulation of bacteria re-emerge. In addition, the back of the head is not smooth and the spaces and depressions can become larger as the time of use increases. Irregularities on the surface of the back can lead to injuries to the mouth. The aforementioned disadvantages are eliminated extensively in the aforementioned embodiment (DE 37 24 640 C2), in which the frame on the rear part is closed and the wall thickness of the bottom of the frame along a closed line is weakened by a very similar to a so-called film articulation, in such a way that the bottom area within the weakening line is joined by means of a resilient connection to the remaining background area. The resulting pressure piece can be displaced when the pressure is applied with the finger and can act directly on the support in order to expel the dental hygiene part. This construction has the additional advantage that the manufacturing tolerances for the fixing means can be chosen closely without taking into account the ejection function of the pressure piece. Nevertheless, it is disadvantageous that this construction necessarily only allows a small stroke or travel on the pressure piece. In addition, the head must be made of a relatively high grade plastic, in order to ensure the spring characteristics for the pressure piece. In addition, fatigue fractures can easily occur in the area of the spring-like connection of the pressure piece and the bottom. Since the spring joint also necessarily requires spaces on the back of the head that reduce the wall thickness, the hygiene requirements are also only met in an inappropriate manner and here again injuries to the oral cavity can occur. The problem of the invention is to build a dental hygiene device of the aforementioned construction, which meet the special hygiene requirements and improve the characteristics of use. According to the invention this problem is solved since on the back of the head a closed opening is provided by the pressure piece and in which the dental hygiene part is coupled and because the pressure of pressure is constructed as a disc of flexible plastic and sealingly engages the wall opening with its circumferential edge. The construction according to the invention essentially comprises three parts, i.e. the head, which is optionally equipped with a handle, the dental hygiene part inserted in a depression of the head and which is at least partially engaged in the head. opening (or hole) of the head and the separate pressure piece constructed as a flexible plastic disc and sealingly sealant marginally to the wall of the opening. In this construction, the manufacturing tolerances for the attachment connection of the dental hygiene part and the head are independent of the ejection function of the pressure piece. Accordingly, the design of the fixing connection can be directed exclusively to the use function, i.e. fixing and releasing. The nature of the adjustment of the pressure piece to the wall of the opening (or hole) and the material of the pressure piece can be chosen exclusively with a view to the proposed use. Since the elasticity necessary for the ejection is only effected by means of the design of the disc, the frame forming the head is not subjected to weakening and the travel of the pressure piece can be optimized functionally. The opening (or hole) in the head is hermetically sealed, in such a way that a smooth surface is obtained. In addition, open spaces are avoided with the resulting hygiene problems. The travel of the pressure piece and its spring behavior during ejection can be optimized from the point of view of use, in such a way that the user senses the function in a sensitive or acoustic manner and these effects can be optionally aided by a design corresponding to the fixing connection separated from the function of the pressure piece. Preferably, the dental hygiene part has a needle located in the head depression located in the opening to the disc, the needle is preferably guided in the opening. This leads to a free arrangement of separations of the dental hygiene part in the head and in particular facilitates the insertion of the dental hygiene part to the head by means of the guide of the needle. The needle in the dental hygiene part and the hole above the head can be provided in an optimal position for insertion and expulsion. Advantageously, the disc ends marginally level with the surface of the back of the head and is curved outwards toward its center. As a result of the convexity it is possible to produce a "click effect" during the ejection process, which appropriately indicates the desired objective, ie the release of the dental hygiene part of the head. The pressure piece can also become sensitive for the blind. The disc can be manufactured from a plastic material different from the head, in such a way that there is also an optimization of the function of the pressure piece from the point of view of the material. Additionally, the disc can be optically differentiated from the head, in order to make the function of the pressure piece visible. Preferably, the disc is made from an elastomer, which permanently ensures the function of the pressure piece and also offers a clamping effect during ejection, while finally preventing injuries in the oral cavity. The disc can be inserted positively or not positively into the opening of the head or can be molded by using a molding process during injection molding of the head. The invention is described in greater detail hereinafter in connection with non-limiting embodiments and the accompanying drawings in which: Figure 1 is a longitudinal cross-sectional view through the head of a toothbrush reproduced in section. Fig. 2 is a section II-III of Fig. 1. Fig. 3 is a section III-III of Fig. 1. Fig. 4 is a section of another embodiment of the brush head for the teeth corresponding to Fig. 3. The embodiments shown in the drawings are concerned with a dental hygiene device or oral hygiene in the form of a toothbrush, wherein only the head 1 is shown. The latter can be attached on the right side of Figure 1 of a conventional handle, which is injection molded in one piece together with the head 1. The dental hygiene device has a replaceable dental hygiene part 12, which in the embodiment represented comprises a plate-like plastic support 3 and a front 4 of bristles of a plurality of bundles 5, connected in a known manner to the support 3. On its underside, the head 1 has a depression 6 similar to a conduit, whose contour corresponds to that of the support 3. The part 2 of replaceable dental hygiene or its support 3 is resiliently coupled in the depression 6 of the head 1 and can be replaced when releasing the fixation connection. In the embodiment shown, the fixing connection is formed since the support has, on at least two front sides (FIG. 3), individual projections 7 or rib-like ribs, corresponding to the corresponding depressions 8 on the side plates 9. of the head. The internal contour of the depression 6 in the head 1 and the external contour of the carrier 3 are made to coincide with each other with close tolerances, in such a way that a pressure settlement of the dental hygiene part in the head 1 is ensured. The head 1 has a through opening (or hole) 11 in its rear part 10, into which a needle 12 formed on the support 3 is coupled and which is guided in the opening 11. A part 13 is provided in the area of the opening 11. of pressure in the form of an elastic disk 14, for example of elastomer, which closes the opening 11 on the rear part 10 of the head 1 and passes in a level manner to the surface of the rear part 10. The disk 14 is somewhat convex compared to the contour of the surface of the rear part 10 and has at its center a duct 15 for the fingers. The disc 14 engages on the needle 12 which is on the support 3, such that when pressure is exerted on the disc 4, the compressive force is transferred to the needle 12 and the part 4 of dental hygiene can be expelled , accompanied by the release of the fixing connections 7, 8. In the embodiment shown in figures 1 to 3, the disk 14 is, during the injection molding of the head 1, sealingly attached and not positively to the same or also united in the use of the molding process. In the embodiment according to figure 4, the depression 6 on the head 1 and the support 3 of the part 2 of replaceable dental hygiene have a different construction. As in the embodiment according to figures 1 to 3, the head 1 has an opening 1, but whose wall is stretched to the depression 6 and has, on its free ends, thickened portions 16, which cooperate with spring retainers 17 on the back of the support 3. To this end, the spring retainers 17 have, inside, recesses or recesses 18 adapted to the thickened portions 16. Conversely, it is naturally possible to build resiliently the wall projecting inwardly. in the form of individual vertical wall portions.

In this embodiment, the support 3 also has a needle 9 which, unlike that of figures 1 to 3, is not guided in the opening 11. The pressure piece 13 is again in the form of a disk 14, which covers the opening 11, but in this case is marginally fixed to the projections 20 on the internal wall of the opening 11. The disk 14 can be mechanically inserted or once again joined in the molding process to the head 1. Welding or adhesion (gluing) are also possible to fix the disc 14. The expulsion of the part 2 of worn dental hygiene is carried out in the same way by exerting pressure on the disc 14, which is transferred to the needle 19 and leads to the release of the fixing connections 16, 17, 18. It is noted that, in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects to which it refers . Having described the invention as above, property is claimed as contained in the following:

Claims (9)

1. Rei indications 1. A dental hygiene device with a handle, a head and a dental hygiene part insertable in a way to fix it in a depression thereof and which can be expelled by means of a resilient pressure piece that is on the back of the head and acting when pressure is exerted on the back part of the dental hygiene part, characterized in that the head on the back part has a hole or opening closed by the pressure piece and in which the part of dental hygiene and because the pressure piece is constructed as a flexible plastic disc and whose circumferential edge is sealably fixed on the wall of the opening. The dental hygiene device according to claim 1, characterized in that, in its rear part, located in the depression of the head, the dental hygiene part has a needle that engages in the opening to the disc. 3. The dental hygiene device according to claim 2, characterized in that the needle is guided in the opening. 4. The dental hygiene device according to any of claims 1 to 3, characterized in that the disc ends marginally level with the surface of the posterior part on the head and is curved out towards its center. The dental hygiene device according to any of claims 1 to 4, characterized in that the disc 14 is manufactured from a plastic material different from the head. 6. The dental hygiene device according to claim 5, characterized in that the disc is made of an elastomer. The dental hygiene device according to claim 5 or claim 6, characterized in that the disc is optically differentiated from the head. The dental hygiene device according to any of claims 1 to 7, characterized in that the disc is inserted into the opening of the head in a substantially positive or non-positive manner or by itself. The dental hygiene device according to any of claims 1 to 8, characterized in that the disc is molded in the molding process in relation to injection molding of the head.