HRP20220352T1 - Handheld aesthesiometer - Google Patents

Claims (15)

1. Hand-held aesthesiometer (1), which contains - a gas tank (4), connected by an interface of the first valve means (5) to a source (2) of gas, which contains an expandable cavity (6) intended to receive a volume of gas (3) in the filling phase (A) of the aesthesiometer, an expandable cavity (6) has a movable wall (6a); - an output nozzle (12), connected to the gas tank (4) by an interface of another valve means (13), suitable for directing the exhaust (14) of the volume of gas (3) located in the gas tank (4) in the discharge phase (C) of the aesthesiometer towards the target , for example the patient's corneas; and - the mechanism (7) which ensures, in the previously mentioned discharge phase (C) of the aesthesiometer, the release of the exhaust (14) of the volume of gas (3) contained in the gas tank (4) in the direction of the exit nozzle (12) by means of the controlled contraction of the expandable cavity (6) of the gas tank in order to ensure a mostly constant output pressure, the mentioned mechanism (7) contains - means for accumulating elastic potential energy (8), which accumulates potential energy from the effects of the expansion of the expandable cavity (6) during the filling phase (A) of the aesthesiometer and which can release said potential energy during the discharge phase (C) of the aesthesiometer, - and a transmission means (9) that mechanically connects the movable wall (6a) and a means for accumulating elastic potential energy (8), the previously mentioned transmission means (9) includes transmission by a rack and pinion, whereby part of the rack (10) is connected on the movable wall (6a) of the expandable cavity (6) and part of the gear (11) is connected to the means for storing the accumulation of elastic energy (8), all in such a way that - in the filling phase (A) of the aesthesiometer, during which the gas (3) enters the expandable cavity (6), the expansion of the said expandable cavity (6) is obtained by moving its movable wall (6a), in turn moving part of the toothed rack (10) in the first in the direction that ensures the rotation of the gear part (11) around the rotary shaft (11a) and in the direction of filling the elastic potential energy accumulation means (8); and - in the discharge phase (C) of the aesthesiometer, when connecting the expandable chamber (6) to the output nozzle (12), the means for accumulating elastic energy (8) releases the accumulated potential energy by applying a moment of force (M) to the part of the gear (11) that ensures movement part of the toothed rack (10) in the direction opposite to the first, which results in the movement of the movable wall (6a) of the expandable cavity (6) in this case in the direction of its contraction, ejecting the exhaust (14) of gas from the volume of gas (3) accumulated inside it during the phase filling (A). 2. Esthesiometer (1) according to claim 1, characterized in that the means for accumulating elastic potential energy (8) contains at least one spring of constant force (18, 18') which stretches during the filling phase (A) of the aesthesiometer and which suddenly releases a constant return force (F) during the discharge phase (C). 3. Esthesiometer (1) according to claim 2, characterized in that the mechanism (7) contains - a support body (15) for a constant force spring (18), equipped with a winding reel (15b) on which said spring is wound/unwound and a straight guide (15a) for controlling the displacement of the spring's driving end (18a) by which it is connected to the gear part (11); and thus yes - the connection between the above-mentioned driving end (18a) of the spring (18) and the part of the gear (11), which determines the point of application (P) of the return force (F) acting on this part of the gear (11) in the discharge phase (C) of the aesthesiometer, is a joint which is movable in a guided manner to maintain a distance (p) with respect to the fixed rotary shaft (11a) of said gear part (11), thereby ensuring that the return force (F) applies a moment of force (M) to part of the gear (11) with a mostly constant value. 4. Esthesiometer (1) according to the previous claim, characterized in that at least one of the support body (15) or the gas tank (4) is placed in the aesthesiometer with the possibility of taking different stable positions, each offering a) or a different distance (p) of the application point (P) of the return force (F) in relation to the rotary shaft (11a) of the gear part (11) at the beginning of the discharge phase (C); b) or a different magnitude of spring stretching (18) at the beginning of the discharge phase (C); or c) a different combination of both effects a) and b) for each position. 5. Esthesiometer (1) according to any of the preceding claims, characterized in that the first valve means (5) enables at least two working positions, - closing position (5a) in which communication between the gas source (2) and the gas tank (4) is disabled; and - filling position (5b) in which communication is enabled between the pressurized gas source (2) and the gas tank (4), the aesthesiometer further contains means for detecting (19) the expansion of the expandable cavity (6) of the gas container (4) which are able to generate a control signal of the first valve means (5) and in which case they move from filling position (5b) to closing position (5a) ) when the previously mentioned expandable cavity (6) reaches the expansion measure corresponding to the predetermined volume (V1) of the gas (3) associated with the emptying of the aesthesiometer and the end of the filling phase (A). 6. Esthesiometer (1) according to the previous claim, characterized in that the detection means (19) contain an optical sensor. 7. Esthesiometer (1) according to any of the preceding claims, characterized in that the expandable cavity (6) is selected from a group of pistons (6a); bag (6b) or axial bellows (6c). 8. Esthesiometer (1) according to any of the preceding claims, characterized in that it has a discharge counter (20). 9. Esthesiometer (1) according to claims 5 and 8, characterized in that the discharge counter (20) counts how many times the detection means (19) detect that the expandable cavity (6) reaches an expansion measure corresponding to a predetermined volume of gas (3) sufficient for one exhaust (14) or by emptying the aesthesiometer. 10. Esthesiometer (1) according to any one of claims 8 or 9, characterized in that it is equipped with a visual and/or sound indicator (21) indicating that the number of discharges has reached a predetermined value. 11. Esthesiometer (1) according to any of the preceding claims, characterized in that the mechanism (7) can ensure, in the previously mentioned emptying phase (C) of the aesthesiometer, the release of the exhaust (14) of the gas (3) contained in the gas tank (4) in direction of the exit nozzle (12) within a time between 0.3 s and 0.7 s, preferably between 0.4 s and 0.6 s. 12. Esthesiometer (1) according to any of the preceding claims, characterized in that the mechanism (7) ensures, in the previously mentioned discharge phase (C) of the aesthesiometer, the output pressure, measured at 4 mm from the opening of the output nozzle (12), according to the rectangular impulse of the nominal values between 0.0003 bar and 0.01 bar. 13. Esthesiometer (1) according to any of the preceding claims, characterized in that the source (2) of gas (3) is made of a variable cartridge of compressed medical gas. 14. Esthesiometer (1) according to any one of claims 1 to 12, characterized in that it is equipped with an actuator for the controlled expansion of the expandable cavity (6), which enables suction of the surrounding gas, in the form of air, via the first valve means (5). 15. Esthesiometer (1) according to the previous claim, characterized in that the actuator for controlled expansion of the expandable cavity (6) moves the movable wall (6a) of said expandable cavity (6), said actuator can be capable of maneuvering or motorization.