SUBMERGIBLE LARYNGOSCOPE BATTERY HOUSING

Abstract: A laryngoscope (10), has a blade (12) and a hollow body including a handle (11) and a cap (30) (see Fig. 2). The handle receives dry cells through an open end, closed by the cap (30). A sealed window (60) (Fig. 8) carried by the cap passes light from a light source (25) within the body to a predetermined zone at the cap exterior, whereby such light may be transmitted along the blade (12) removably attached to the cap. A flexible barrier (29) is carried by the cap (30) to be deflected by the blade (12) upon its attachment to the cap (30), the barrier (29) sealing off between the cap interior and exterior. Circuitry including a motion transmitting element (33) to be deflected within the hollow body in response to barrier (29) deflection to establish an ON condition of the circuitry for transmitting current from the dry cells (37) to the light source.

Description: This invention generally relates to examining devices such as laryngoscopes and particularly to an improved submersible device of this type. Laryngoscopes generally comprise a blade and a cooperating handle which are connected together in an L-shaped configuration. The hollow handle normally serves as an enclosure for a power supply such as one or more dry cells which are adapted to energize a light bulb. The light from the bulb passes to the distal end of the blade to illuminate the patient's mouth and larynx during the examination thereof by medical personnel. A surface on the blade is used to press against the tongue and mandible of a patient in a supine position in order to prevent the patient's tongue from obstructing the visual examination of the larynx by medical personnel. A laryngoscope of this kind is disclosed in EP-A-0 169 497 While the instrument is useful for examining the larynx, the primary function of the laryngoscope is to expose the larynx in order to facilitate the insertion of an endotracheal tube. The surface of the laryngoscope blade adjacent the handle is urged against the tongue and mandible to expose the larynx in such procedures and the opposite blade surface is positioned opposing the upper front teeth of the patient. It becomes desirable to provide a re-usable blade and handle which then must be cleaned thoroughly after use since fluid from the patient's mouth area can contaminate the handle. However, washing of the handle presents the problem of fluid gaining access to the power supply, i.e. dry cells, within the handle hollow, as via one or both ends of the handle. This is a particular problem when the light bulb is carried at the end of the handle to which the blade attaches, as cleaning fluid can leak past the bulb into the handle to cause bulb circuit malfunction. DE-A-1,566,116 discloses a bronchoscope having a blade, a hollow body means comprising a handle and a cap. The handle is adapted to receive dry cells and has an open end. The cap removably interfits the handle to close its open end and means is provided sealing off between the cap and the handle. Also, means is carried by the cap to pass light from a light source within the body means to a predetermined zone at the cap exterior whereby the light may be transmitted along the blade which is removably attached to the cap. Circuit means including a motion transmitting element to establish an ON condition of the circuit means transmits current from the dry cell means to the light source in use of the device. DE-A-2,358,042 discloses a flashlamp having a fluid tight handle enclosure for dry cells containing also fluid tight switching means comprising a motion transmitting element movable in response to the manual deflection of a flexible barrier to establish an ON condition of a circuit means for lighting the lamp. SUMMARY OF THE INVENTION Proceeding from the disclosure of DE-A-1,566,116, the present invention provides a laryngoscope having a blade and hollow body means including a handle and a cap, the handle being adapted to receive dry cell means, the handle having an open end, the cap removably interfitting the handle to close said open end, means sealing off between the cap and handle, means carried by the cap to pass light from a light source within said body means to a predetermined zone at the cap exterior, whereby said light may be transmitted along the blade removably attached to the cap, and circuit means including a motion transmitting element to establish an ON condition of the circuit means for transmitting current from said dry cell means to said light source, characterised in that the cap fits the handle telescopically, in that a flexible barrier is carried by the cap to be deflected by the blade upon its attachment to the cap, the barrier (29) sealing off between the cap interior and exterior, in that said motion transmitting element extends proximate said flexible barrier to be deflected thereby, in that said open end of the handle is the sole open end thereof, and in that the handle is formed in one piece. As will appear, the handle, cap or blade, or combination thereof may consist of light-weight molded plastics material interfitting in such manner as to preserve laryngoscope functions while preventing fluid access to the cap and handle interior during washing. Furthermore, the receptacle may comprise a molded plastics unit having electrically conductive plating thereon, the plating having at least two sections which are not electrically connected, one section being electrically connectible to a dry cell plus terminal, and the other section being electrically connectible to a dry cell negative terminal. Also, said cap may define two substantially rectangular sub-chambers one receiving said barrier and motion transmitting element, and the other receiving said light source, a light reflector, and a window sealingly engaging an end wall defined by the cap. One way of carrying out the present invention will not be described in detail by way of example with reference to drawings which show one specific embodiment. In the drawings:- Fig. 1 is a side elevational view of a laryngoscope at the time of use on a patient, and which embodies features of the invention; Fig. 2 is a perspective view of the laryngoscope blade and handle end, prior to their assembly; Fig. 3 is a side elevational view, partially in section, of a laryngoscope, with the blade in ready position; Fig. 4 is a partial side elevational view, partially in section, of the laryngoscope, with blade in operative position; Fig. 4 a is a cross sectional view taken along lines 4a-4a shown in Fig. 4; Fig. 5 is a section taken in elevation showing details of the handle portion of the laryngoscope; Fig. 6 is an end view taken in elevation on lines 6-6 of Fig. 5; Fig. 7 is a section taken in elevation on lines 7-7 of Fig. 5; Fig. 8 is an enlarged plan view section taken on lines 8-8 of Fig. 5; Fig. 9 is an end view taken in elevation on lines 9-9 of Fig. 8; Fig. 10 is a section on lines 10-10 of Fig. 8; Fig. 11 is a section on lines 11-11 of Fig. 10; Fig. 12 is a fragmentary section taken on lines 12-12 of Fig. 8; and Fig. 13 is a schematic view of circuitry. DETAILED DESCRIPTION The laryngoscope 10, which comprises a handle 11 and blade 12, is utilized to depress the patient's tongue and mandible 13. Frequently, the patient's front teeth 14 are used as a fulcrum for the blade 12, in order to more completely expose the larynx during examination, and to insert an endotracheal tube. In order to couple the blade 11 to the handle 12, and as shown in Figs. 2 to 4, the upper end of the handle 11 has an open channel 15 provided with a pivot rod 16 extending between flanges 17. The inner side of one flange has a groove or dimple 19 adapted to seat detent 20 projecting at one side surface 18 of a boot shaped appendage on the blade. The boot shaped appendage 22 interfits into the open channel 15 and is mounted therein in a pivotal fashion. The front end 23 of the boot shaped appendage 22 is hooked under the pivot rod 16 during the pivotal mounting thereof, in a conventional fashion. To mount the blade onto the handle 11, the appendage 22 of the blade 12 is inserted into the open top channel 15 with a pivotal motion so that the front end 23 rotates under the pivot rod 16 i.e., from Fig. 3 to Fig. 4 condition. The detent 20 moves into engagement with the groove 19 provided in the surface 18, to thereby snap-retain the appendage 22 in firm interfit with the channel and pivot rod 16, as the blade moves from ready position, as shown in Fig. 3, to fixed position seen in Fig. 4. A light such as an incandescent bulb 25 is provided at the end of the handle proximate the blade to be activated when a light switch 24 is closed by a motion transmitting element 33, as when pushed by bottom surface 26 of appendage or boss 22, via a flexible sealing barrier 29. As shown in Fig. 3, when the blade 12 is initially mounted on the handle 11, the blade 12 is in a ready position on the handle 11 but the bottom surface 26 of the appendage 22 does not activate, i.e. depress, the light switch. Further rotation of the blade 12 causes the detent 20 to engage the groove 19, and to thereby lock the blade 12 in an operating position and simultaneously therewith to cause metallic bottom surface 26 to depress, i.e. activate the light switch 24, which in turn energizes the light source 25. As best shown in Figs. 2 to 4, light is directed from the light source 25 to ensure the proper illumination of a patient's mouth and larynx when the laryngoscope is being used. The light source or bulb 25 is located near the bottom wall 15 a of channel 15 so that, when the blade 12 is rotated into its final operating position, not only is switch 24 engaged, but also the energized bulb directs light into the end 28 a of the light pipe or duct 28 carried by the blade and conducting light to the light emitting end 28 b directing light forwardly from a channel in blade web 32. Duct 28 may be of optical fiber. The switch 24 and bulb 25 are both contained in a lightweight plastics cap 30 which fits telescopically into the lightweight plastics handle body 31, as better seen in Figs. 5 and 8. As there shown, the cap 30 has a skirt 30 a received into the body bore 31 a , to shoulder at 32 and 32 a . O-ring seal 34, typically of rubber and carried by skirt 30 a , seals off between that skirt and bore 31 a . A boss 35 integral with the skirt removably fits or snaps into an opening 36 in the body wall 31 b , as shown, to lock the cap in position. Accordingly, the open end of body 31 is closed by the cap. Body 31 receives dry cells 37 that supply electrical energy to the incandescent bulb when switch 24 is closed. Reference is now made to Fig. 13, showing partially schematically, the integration of circuit means, dry cells, element 33, switch 24, barrier 29, pusher 22 on the blade, and bulb 25. The element 33 may with unusual advantage comprise a nose-shaped part projecting into a corresponding recess 29 a formed by the elastomeric barrier 29 which is peripherally retained in position by the cap, as shown at 40 in Fig. 8. In that view, and in Fig. 12 the barrier 29 and part 33 are shown to extend within a sub-chamber 41 formed by cap walls 42 to 45, and the barrier seals off access to the interior 46, via sub-chamber 41. The latter has a substantially rectangular cross section to interfit part 47 to be described. Returning to Fig. 13, the part 33 may with unusual advantage be integrally molded with an elongated holder or bracket 47 having components 47 a to 47 h , these being identified further as follows: --47 a - arm supporting part 33 and adapted to bend as blade part 22 pushes against barrier 29 to deflect part 33 leftwardly and close the switch, --47 b - support for arm 47 a and fitting cap wall 43 a , --47 c - switch terminal to be engaged by part 33, to close the switch, --47 d - projection that supports terminal 48 engaged by battery contact 49, --47 e - support arm that supports 47 b , 47 c and 47 d , and connects them to holder base stretch 47 f , --47 f - base stretch that may support batteries 37 to form a sub-assembly insertible into the body 31 and into cap 30, --47 g - connects base stretch 47 f to terminal 47 h , --47 h - terminal that engages the left battery contact end face 49 a . The said bracket 47 and part 33 thereof may be molded of lightweight strong plastics material and coated with a thin conductive metallic layer, such as silver, except for regions 50 and 51. As a result, when part 33 closes against switch terminal 47 c , electrical current flows along the following path: from battery contact 49 through coatings on 47 d , 47 c 33, and 47 b to conductor 52 to bulb 25, then through conductor 53 to coatings on parts 47 f , 47 g and 47 h to the battery contact face 49 a . Batteries 37 are of course themselves in end-to-end conductive contact at 54. Referring now to Figs. 5, 8 and 9, the cap 30 also defines a second sub-chamber 55 which may be rectangular in outline, as defined by walls 43 a , 55 a , 55 b and 55 c . End wall 56 of sub-chamber 55 contains an aperture 57 to pass light from bulb 25 to optical fiber light pipe 28, via the end thereof 28 a , as previously described. A light passing means in the form of window 60 serves to transmit light from the bulb and reflector 60 a toward and onto the end 28 a of optical light pipe 28, as also shown in Fig. 13. Window 60 may consist of plastics material and be bonded to the inner surface of end wall 56 at 63, to seal-off the rectangular outline sub-chamber 55 from the exterior, whereby the interior 46 of the handle is kept free from exterior moisture of liquid. As also shown in Fig. 8, the bulb base 25 a is received in bore 64 of a bulb holder 65, which in turn is received in a bracket 155 that fits closely to walls 55 a to 55 c , and also to part 47 b of the receptacle 47. Conductor 53 indicated schematically in Fig. 13 may take the form of conductive holder 155 in Figs. 8 and 9, and conductor 52 in Fig. 13 may take the form in Figs. 8 and 10 of a tab integrally molded with the receptacle 47, and projecting to engage an insert terminal 68 which in turn engages the bulb contact 70. In the views shown in Figs. 10 and 11 the bracket 155 is shown as U-shaped to receive holder 65. Its exterior is rectangular to fit in the cap rectangular sub-chamber 55.

Claims: A laryngoscope (10) having a blade (12) and hollow body means including a handle (11) and a cap (30), the handle (11) being adapted to receive dry cell means (37), the handle having an open end, the cap (30) removably interfitting the handle to close said open end, means (34) sealing off between the cap (30) and handle (11), means (60) carried by the cap (30) to pass light from a light source (25) within said body means (11, 30) to a predetermined zone at the cap exterior, whereby said light may be transmitted along the blade (12) removably attached to the cap (30), and circuit means (48, 47, 52, 53, 24) including a motion transmitting element (33) to establish an ON condition of the circuit means (48, 47, 52, 53 24) for transmitting current from said dry cell means (37) to said light source (25), characterised in that the cap (30) fits the handle (11) telescopically, in that a flexible barrier (29) is carried by the cap (30) to be deflected by the blade (12) upon its attachment to the cap (30), the barrier (29) sealing off between the cap interior and exterior, in that said motion transmitting element (33) extends proximate said flexible barrier (29) to be deflected thereby, in that said open end of the handle is the sole open end thereof, and in that the handle is formed in one piece. A laryngoscope as claimed in claim 1, wherein the cap (30) has a first zone (55) to receive a light bulb (25), and a second zone (41) receiving a switch (24) which, when closed, completes a circuit between the power supply (37) and the light bulb (25), a window (26) carried by the cap (30) and closing a first opening (57) in the cap to pass light from the light bulb (25), the first and second zones (55, 41) being located in side-by-side relation, only said flexible barrier separating said second zone from the exterior of the cap. A laryngoscope as claimed in claim 2, wherein said cap (30) has a wall (15a) defining a second opening (40) across which said flexible barrier (29) extends, to block fluid access from the cap exterior via said second opening (40) to the interior of the cap. A laryngoscope as claimed in claim 3, wherein each of said openings (57, 40) is substantially rectangular in cross section. A laryngoscope as claimed in any preceding claim, wherein said circuit means includes a battery receptacle (47) received endwise into said hollow handle (11) and into said cap (30) to interfit same and said motion transmitting element (33) is integral with said receptacle and positioned to extend proximate said flexible barrier to be deflected thereby, and switch terminals (47a, 47c) are carried by said receptacle (47) to be closed together in response to said deflection of the motion transmitting element (33). A laryngoscope as claimed in any preceding claim, wherein said cap (30) defines two substantially rectangular sub-chambers (41, 55) one receiving said barrier (29) and motion transmitting element (33), and the other receiving said light source (25), a light reflector (60a), and a window (60) sealingly engaging an end wall (15a) defined by the cap (30). A laryngoscope as claimed in any preceding claim, wherein each of said handle (11) cap (30) and blade (12) consist of molded plastics material.

Inventors: BAUMAN, JACK
Applicants: BAUMAN, JACK
Application year: 1987
Main classification: A61B1
IPC codes: F21V31, A61B1