The invention relates to an ear fitting piece for creating an ear impression, as well as a method for creating an ear impression.
Such an ear fitting piece is used to map the contour of an ear and, in the case of hearing devices in particular the contour of an auditory canal of a patient, so that the ear fitting piece represents a negative mold of an ear section to be mapped. This negative mold can now be used to create a personalized hearing device. The hearing device here is tailored to the shape of the auditory canal of a patient, to ensure that it is comfortable to wear and the transmission quality is optimal. The ear fitting piece serves as a reference for this. With the ear fitting piece it is possible to personalize and therefore improve both in-the-ear hearing devices and behind-the-ear hearing devices.
The personalized ear fitting piece is generally created using a soft plastic material, which is introduced into an auditory canal of an ear of a patient. When the plastic material has hardened in the ear, the plastic mass is removed from the ear. The plastic mass now has an outer contour, which corresponds to the inner contour of the corresponding auditory canal of the patient. This negative mold can now be used to produce a personalized hearing device with the aid of known means.
An ear insert for hearing devices is known from DE 88 16 266 U1, featuring a mold element to be tailored to the auditory canal of the user, which is made of an initially viscous, then hardenable material, enclosed in a protective sleeve.
Vehicle upholstery is described in DE 102 27 131 A1, the shape of which can be changed by changing the aggregate state of a liquid.
DE 10 2005 009 348 A1 relates to a solidifiable material, for example a thermoplastic, a duroplastic, a synthetic foam or a crystallizable liquid, serving as a filler mass for molding.
The object of the present invention is to allow the creation of an ear impression in an economical manner.
According to the invention this object is achieved by the apparatus as claimed in claim 1, i.e. by an ear fitting piece for creating an ear impression, comprising:
wherein a further change of state can be brought about from the second state to the first state of the liquid by heating.
The object is also achieved by a method for creating an ear impression, consisting of the following steps:
Advantageous developments of the invention are defined in the respective dependent claims.
In the first state the ear fitting piece should have the property that it can be inserted easily into an auditory canal of an ear of a patient. This can be controlled by the selection of the soft rubber sleeve and the liquid. The soft rubber sleeve here should have the property that the liquid is securely enclosed and should have mechanical stability such that the soft rubber sleeve is not damaged by insertion into the auditory canal and the change of state that takes place. As soon as the ear fitting piece fills the necessary region of the auditory canal of the patient, the activating means can be used to bring about a change of state of the liquid. The state of the liquid here changes so that a solidified state of the liquid results from the moldable state. The ear fitting piece now has a negative shape of the filled region, thus forming the ear impression. Once the liquid is in the second state, the ear fitting piece can be removed from the auditory canal of the patient. The solidified state of the liquid here should have such rigidity that the ear fitting piece can be removed from the auditory canal of the patient and still have the negative shape assumed after the change of state. This provides the personalized ear impression of the patient.
This ear impression can be used for example to create a patient-specific hearing device. The personalized ear impression is “read in”, for example using an optical measuring system, in which the geometric shape of the ear impression is read into a system. This data can then be used for further processing as desired.
The disadvantage of a conventional ear fitting piece is that the finished ear fitting piece cannot be reused to create a new ear impression, as its shaping and solidification are irreversible.
Because heating the liquid in the inventive ear fitting piece brings about a further change of state of the liquid, specifically a “return” to the first state, it is possible to reuse the inventive ear fitting piece to create a new ear impression. Therefore the same ear fitting piece can be used to create a number of ear impressions. This has the advantage that a single-use item is replaced by a reusable item and the user only has a one-off purchase cost. A further advantage is that if a first attempt to create the ear impression fails, the process can be repeated as often as necessary with the same ear fitting piece. Since the ear fitting piece can be reused, the patient for whom an ear impression is being created incurs fewer costs. Also less waste is created.
In one advantageous embodiment of the invention the activating means makes contact with the liquid.
Since the activating means is in direct contact with the liquid, a fast pulse emission can take place, to bring about the change of state.
In a further advantageous embodiment of the invention the change of state of the liquid is a phase transition from liquid to solid and the further change of state of the liquid is a phase transition from solid to liquid.
Because the change of state is a phase transition from liquid to solid, it can be ensured that the ear fitting piece has the necessary mechanical stability required during subsequent further processing. The further change of state of the liquid, in which the phase transition from solid to liquid takes place, ensures that the ear fitting piece has the necessary moldability and elasticity required to create a new ear impression.
In a further advantageous embodiment of the invention the liquid is formed by a latent heat storage material, in particular with a salt or paraffin base.
This has the advantage that the further change of state of such liquids is in a range outside normal ambient temperature. This allows the ear fitting piece to be brought easily to the second state and to harden in this state. Conversion to the first state only takes place when the further change of state is brought about by heating. Since with such materials the further change of state can be set so that it is outside normal ambient temperature, the process can be controlled specifically. An inadvertent change in the liquid from the second state to the first state can thus be avoided. Also it means that there is no urgency to measure the ear fitting piece once the second state has been brought about.
In a further advantageous embodiment of the invention the activating means is configured to generate a pressure wave in the liquid.
It is possible to bring about the change of state from the first state to the second state, in particular by means of a pressure wave in the liquid, such as for example a latent heat storage material. A pressure wave can be brought about for example by a small metal sheet located in the liquid.
In a further advantageous embodiment of the invention the activating means comprises a piezo element.
The piezo effect can be utilized in that an electric voltage applied to the activating means causes the activating means to perform a mechanical movement. The mechanical movement here is intended to generate a pressure wave in the liquid. A crystallization process is hereby initiated, bringing about the change of state, particularly if the liquid is formed by a latent heat storage material. An electric voltage can likewise initiate the crystallization process so that the activating means utilizes the piezo effect in that when the user generates a mechanical movement at the activating means, an electric voltage is produced at the liquid, which ultimately brings about the change of state.
In a further embodiment of the invention, after being brought about by the activating means, the second state of the liquid is permanent until the further change of state.
This ensures that the ear fitting piece can be removed from the auditory canal of a patient without mechanical damage and has the necessary stability for subsequent measuring.
In a further advantageous embodiment of the invention the liquid is configured so that the change of state takes place within 15 seconds.
This has the advantage that the process of activating the ear fitting piece introduced into the auditory canal of the patient until the second state of the liquid is reached is within a manageable time frame for patient and user.
In a further advantageous embodiment of the invention the activating means is configured and dimensioned so that it can be gripped and activated using the fingers when the ear fitting piece is introduced into an auditory canal of a person.
This makes it easy for the user to activate the change of state and remove the ear fitting piece once the liquid has solidified. Also the ear fitting piece can be held or fastened for example for further processing at this point, without the risk of the negative mold of the auditory canal, formed by the soft rubber sleeve and the solidified liquid contained therein, being mechanically destroyed.
In a further advantageous embodiment of the invention the ear fitting piece is configured so that it essentially maintains its volume during the change of state.
This ensures that an ear impression is created which is true to the original so there is no distortion of the ear to be measured.
The invention and embodiments of the invention are described and explained in more detail below with reference to the exemplary embodiments illustrated in the figures, in which:
Number | Date | Country | Kind |
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10 2009 023 302.4 | May 2009 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP2010/057168 | 5/25/2010 | WO | 00 | 11/29/2011 |