MEDICAL DEVICE HAVING AN IMPULSE FORCE-RESISTANT COMPONENT
A vibrator including a housing, a transducer mounted in the housing such that there is a gap between the housing and transducer; and an impulse force damper that substantially fills the gap. Such a damper includes: a first layer in contact with the housing; and a second layer in contact with the transducer and the first layer; wherein substantially no adhesion is exhibited between the first and second layers or between at least one of the first and second layers and at least one of the housing and the transducer.
1 . A vibrator comprising:
a housing;
a transducer positioned within the housing such that there is a gap between the transducer and housing; and
an impulse force damper, disposed in the gap between the housing and at least a portion of the transducer, configured to mechanically isolate at least a portion of the transducer and the housing, and to minimize impulse forces applied to the transducer relative to that which would be the case in the absence of the impulse force damper.
2 . The vibrator of claim 1 ,
wherein for at least one of a plurality of regions of the gap between the housing and the at least a portion of the transducer, the impulse force damper fills the gap in that at least one region, and
wherein said impulse force damper is configured to minimize adhesion between abutting surfaces of at least one of the damper/housing interface and the damper/transducer interface.
3 . The vibrator of claim 1 , wherein said damper is formed of an elastic damping material.
4 . The vibrator of claim 3 , wherein, in response to a decrease in distance between the housing and transducer in the at least one region, the elastic damping material deforms by laterally expanding thereby increasing dimensions of the at least one region.
5 . The vibrator of claim 2 , wherein the damper is configured to provide at least an effectively negligible load on the transducer relative to that which would be the case in the absence of the damper.
6 . The vibrator of claim 1 , wherein the damper has a mass that is effectively insubstantial relative to the mass of the transducer so as to minimize an effect on an output response of the vibrator relative to that which would be the case in the absence of the presence of the damper.
7 . The vibrator of claim 1 , wherein the damper comprises:
a first layer of a first material in contact with one of either the housing and the transducer; and
a second layer of a second material in contact with the other of either the housing and the transducer,
wherein the first and second layers have abutting surfaces defining a first layer/second layer interface.
8 . The vibrator of claim 7 , wherein the first and second materials are antifriction materials with respect to each other.
9 . The vibrator of claim 8 , wherein one of the first and second materials is an elastic damping material.
10 . The vibrator of claim 9 , wherein the one of the first and second layers formed by the elastic damping material is a substantial volume of the damper, and the other of the first and second layers has a negligible thickness.
11 . The vibrator of claim 10 , wherein the other of the first and second layers substantially conforms to manufacturing and assembly tolerances in the surface of the abutting surface of one of the housing and transducer.
12 . A bone conduction device, comprising:
a mass;
an actuator configured to move the mass to generate vibrations to evoke a hearing percept; and
a housing encompassing the mass and the actuator, wherein
a damper is located in a space between a housing wall of the housing and the mass.
13 . The bone conduction device of claim 12 , further including:
an arm, wherein the mass is located at a first end of the arm, and the arm is connected to the actuator at a location away from the first end of the arm, wherein
the actuator moves the arm, thereby moving the mass.
14 . The bone conduction device of claim 12 , wherein:
the damper extends from the mass to the wall of the housing.
15 . The bone conduction device of claim 12 , wherein:
the damper includes a damper material and an isolation layer that separates the damper material from one of the mass and the housing wall.
16 . The bone conduction device of claim 12 , wherein:
the damper is a first damper;
the bone conduction device includes a second damper located in a second space between another portion of the housing and another side of the mass on an opposite side of the mass from the first damper.
17 . The bone conduction device of claim 12 , wherein:
the bone conduction device is configured such that output of the bone conduction device to evoke a hearing percept is at least effectively the same as that which would be the case in the absence of the damper being present between the mass and the housing wall.
18 . A method of damping an impulse force to which a vibrator for an auditory prosthesis is susceptible, the vibrator including a housing, a transducer mounted in the housing and a multilayer damper disposed between the housing and the transducer, the method comprising:
compressing the damper in response to the impulse force, the compressing including:
deforming at least one layer of the damper so as to dissipate energy of the impulse force; and
slipping, due to there being substantially no adhesion between one or more of:
two layers of the damper with respect to each other;
at least one layer of the damper with respect to the housing; and
at least one layer of the damper with respect to the transducer.
19 . The method of claim 18 , further comprising:
imposing, in a quiescent state, substantially no static preload on the transducer by the damper.
20 . The method of claim 18 , wherein the damper is configured to cause a substantially insignificant effect on the frequency response of the vibrator.