US3689761A

US3689761A - Dental operating light

Info

Publication number: US3689761A
Application number: US78681A
Authority: US
Inventors: Cyril Rosen; Stan Patok
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-10-07
Filing date: 1970-10-07
Publication date: 1972-09-05
Anticipated expiration: 1989-09-05

Abstract

A lamp primarily for use as a dental operating lamp which comprises an annular frame which is connected to an arm for mounting the lamp on a support, a light source and lens system mounted on the annular frame with the optical axis of the lens system generally aligned with the axis of the frame and a plurality of annular convection fins removably mounted on both sides of the frame in spaced relationship to one another so as to surround the light source and lens system while allowing an uninterrupted passage for convection currents in substantially all radial directions around the light source. The convection fins are preferably dished so as to form a shade for the light source without impeding the air flow and the lamp is preferably mounted on a support comprising a tubular arm which is adapted to form a continuous conduit for a flexible cable and which includes two joints along the lamp to be rotated through at least 330* about each of two mutually perpendicular axes which axes are preferably both perpendicular to and pass through the optical axis of the lamp.

Description

United States Patent Rosen et al.

[451 Sept. 5, 1972 DENTAL OPERATING LIGHT Filed: Oct. 7,'l970 Appl. No.: 78,681

US. Cl ..240/4l.l5, 240/413 Int. Cl. ..A6lb l/06 Field of Search ..240/41 .15, 46.41 47, 41.3

References Cited UNITED STATES PATENTS 1,884,265 10/1932 Rush ..240/47 X Primary Examiner-Jerry W. Myracle Attomey-Hopgood & Calimafde Sandoe [57] ABSTRACT which comprises an annular frame which is connected to an arm for mounting the lamp on a support, a light source and lens system mounted on the annular frame with the optical axis of the lens system generally aligned with the axis of the frame and a plurality of annular convection fins removably mounted on both sides of the frame inspaced relationship to one 1 another so as to surround the light source and lens system while allowing an uninterrupted passage for convection currents in substantially all radial directions around the light source. The convection fins are preferably dished so asto form a shade for the light source without impeding the air flow and the lamp is preferably mounted on a support comprising a tubular arm which is adapted to form a continuous conduit for a flexible cable and which includes two 1 joints along the lamp to be rotated through at least 330 about each of two mutually perpendicular axes which axes are preferably both perpendicular to and pass through the optical axis of the lamp.

13 Claims, 3 Drawing Figures 6O Mun. if 9 62 um 61 i 72 71 Z llllll l 0' M 70 e9 74 66 43a A 63 z N\ i 56 52d PATENTEDSEP 5|97Z 3,689,761

SHEET 2 [IF 2 Inventors Cyril Rosen and Stan Patok Attornovs Sandoe, Hopgood 5; Calima ma DENTAL OPERATING LIGHT BACKGROUND TO THE INVENTION Known dental operating lamps have the disadvantage that they generate a considerable amount of heat which is not effectively dissipated in all of the angular positions in which the lamp is used and cannot, therefore, always be positioned close to the patients mouthJhey are also relatively bulky because they incorporate a separate bulb and reflector and in many cases they are not fully adjustablein both horizontal and vertical' STATEMENT OF THE INVENTION According to the present invention there is provided a lamp, for use as an operating lamp, comprising an annular frame, means for mounting the lamp, a light source and lens system mounted on the annular frame with the optical axis of the lens system generally aligned with the axis of the frame a plurality of longitudinal members projecting from each side of the frame in parallel with the axis of the frame and a plurality of annular convection fins removably mounted on the said longitudinal members in spaced relationship so as to surround the light source and allow an uninterrupted passage for convection currents in substantially all radial directions from the light source.

According to a further aspect of the invention there is provided a lamp as defined in the preceding paragraph, wherein the said means for mounting the lamp comprises a tubular arm forming a continuous conduit for a flexible cable and including two joints allowing the lamp to be rotated through at least 330about each of two mutually perpendicular axes.

Preferably, the said mutually perpendicular axes are both perpendicular to and pass through the optical axis of the lamp.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal section through a lamp according to the present invention,

FIG. 2 is an end elevation of the lamp of FIG. 1, showing the supporting arm in vertical section, and

FIG. 3 is a section, taken on the line III-III in FIG. 1 of a detail of the lamp.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the drawings, a dental operating lamp is indicated generally at supported on a freely adjustable arm, which is indicated generally at 11.

The arm 11 comprises a ball 12 which is mounted in a fixed tubular support 13 so as to be rotatable in a vertical plane within limits imposed by the abutment of a stem 14 against an end 15 of the tubular support 13. The stem 14 joins the ball 12 to a tubular bush 16 in which a tubular member 17 is rotatably mounted. The tubular member 17 is attached in the bush 16 by a spacer 18 and friction adjusting nuts 19, 20 which are threaded on the the end of the tubular member 17. Located between the bottom end of the spacer l8 and the bush 16 are a flat washer 21, spring washer 22 and friction washer 23. By adjusting the nuts 19, 20, the frictional resistance to rotation of the tubular member 17 within the bush 16 can be varied. The adjusting nuts 19 and20 are hidden by a cap 24 which is threaded on to the upper end of the bush 16. A friction washer 25 is located between the bottom surface of the bush l6 and a co-operating surface of the member 17 and a channel 26 is formed in the upper surface of the tubular member 17. The channel 26 houses two pins, not

shown, one fixed to the bush 16 and the other fixed to the tubular member 17 which allow rotation of the member 17 relative to the bush 16 through at least 330and not more than 360.

A tubular rod 27 is attached integrally to the tubular member 17 and projects at an angle to the axis of rotation of the member 17 and downwardly therefrom. The rod 27 is cranked intermediate its length and a bush 28, which is provided with a tubular switch housing 29 for an electrical switch is mounted on the bottom end of the rod 27. A tubular spigot 30 is mounted for rotation in the lower bush 28 in the same manner as the tubular member 17 is mounted in the bush 16. A pair

offriction adjusting nuts

31, 32, spacer 33, flat washer 34, spring washer 35 and friction washer 36 control the frictional resistance to rotation of the tubular spigot 30 within the bush 28 and a cap 37 is provided to hide the

nuts

31, 32 and prevent the entry of dust and dirt. A friction washer 38 is provided between the tubular spigot 30 and lower bush 28 and

pins

39 and 40 mounted respectively on the lower bush 28 and spigot 30 so as to project into a groove 41 in the tubular member 30, allow for rotation of the spigot 30 through at least 330 and not more than 360 relative to the lower bush and about the axis of the spigot 30.

It will be seen from the above description of the arm 11 that the lamp 10 can be rotated about the two mutually perpendicular axes of the tubular member 17 and the tubular spigot 30 and that the tubular member 17 is perpendicular to and passes through the optical axis of the lamp 10 because of the crankin the rod 27.

It will furthermore be seen that a continuous conduit is formed from the tubular support 13 through the ball 12, tubular member 17, rod 27, tubular switch housing A tubular extension 42 of the spigot 30 is a forced fit into any one of a plurality of tubular radial bores 43a provided in an annular frame 43, which is shown in sec-, tion in FIG. 1. The frame 43 is provided with a central aperture 44 and three equi-angularly arranged axial holes 45, only one of which is shown, and each of which is adapted to receive a rod 47 which forms a part of a convection fin mounting assembly.

There are three

similar fin assemblies

48, 48a and 48b and only the assembly 48 will be described in detail. The assembly 48 comprises the rod 47 which extends through the hole 46 in the ring 43 and which is fixed in position by a transverse grub screw 49. Mounted on each end of the rod 47 are

sleeves

50 and 29 and tubular spigot 30 for a cable leading to the lamp 51. The sleeve 50 carries six convection fins 52a, 52b, 52c, 52d, 52e, 52f and the sleeve 51 carries three

convection fins

53a, 53b and 53c. The fins 52 and the fins 53 are separated from one another by tubular spacers 54 which are slidably mounted on the sleeves 50 and 51.

The fins 52 and 53 are substantially similar and each comprises a flat annular base portion 55 which is formed with three circular holes to receive the rods and sleeves and a dished outer wall or flange 56.

Nuts

57 and 58 are threaded on to the outer ends of the two sleeves 50 and 51 respectively and retaining

dome nuts

59 and 60 are threaded on to the threaded

ends

61, 62 respectively of the rod 47 to complete the assembly.

A light retaining ring 63 is mounted in the e base of the fin 52and supports a tungsten-halogen light 64. The light 64 carries a built-in dichroic reflector and a suitable light of this type carrying a built-in reflector is that sold by Philips Electrical Company under SCIYNO. 6,834. The light 64 is held in position on the ring 63 by a light retaining spring 65.

Mounted on the rear end of the light 64 is a light connector 66 which is electrically connected to a terminal block 67. The terminal block 67 is mounted on the base portion 55 of the fin 53a by a screw 68 and nut 69. The fin 53a has a central aperture of diameter sufficient to receive the screw 68 and is also provided with a plurality of small apertures 55a for the passage of air. A terminal block cover 70 is mounted over the terminal block with the aid of a domed nut 71 which is engaged on the end of the screw 68. As can be seen from FIG. 1, a cable 72 emerges from the spigot 30 and is connected to the terminal block 67 Mounted forwardly of the light 64 is a mask 73 having a variable aperture 74. The mask 73 is mounted in a mask-retaining ring 75 which is itself a push fit into the base portion of the fin 52c.

Mounted forwardly of the mask 73 is a lens 76 which is fixedly mounted in a tubular lens support 77. The lens support 77 is threadedlyengaged in a lens bush 78 which is itself a push fit mounting in the base of the leading fin 52a. The position of the lens 76 on the axis of the lamp is adjustable by threading the lens support inwardly or outwardly and is fixed in position by a transverse grub screw 79.

On the opposite side of the light 64 to the tubular spigot 30, a handle 80 is provided which is mounted on a spigot 81 which is a push fit in a radially positioned hole in the light assembly retaining ring 43. It will be appreciated that the dished outer wall of the fin 53c is provided with cut-outs to accommodate the spigot 30 on one side and the spigot 81 on the other side of the lamp.

In order to connect the lamp to a source of current, a cable (not shown) is fed through the arm 11 to an electrical switch unit (not shown) which is housed in the switch housing 29. From the switch unit, cable 72 leads to the terminal block 67 which is electrically connected to the light 64.

When the lamp is in use, the heat generated by the bulb in the light.64 creates convection currents of air which pass upwardly in the direction of the arrows through the fins past the bulb and upwardly and outwardly from the upper side of the lamp. The convection currents which are generated by the bulb carry the heat of the bulb away and enable the lamp to be used in close proximity to the patients mouth and at any angle without impeding the flow of air around the bulb. The dished shaped of the fins also has the advantage that side-dazzle by the light emitted by the bulb is eliminated or at least reduced while leaving a clear passage for the convection currents of air which are not impeded inany way regardless of the angle of the lamp.

The adjustments which can be made in horizontal and vertical planes to the lamp give exceptional flexibility in the positioning of the lamp and enable any area of the patients mouth to be illuminated with the patients head in any position. If the lamp is positioned with the optical axis directed vertically downwardly then the convection currents escape through the holes 550 in the rear fin 53a.

The light 64, with its own built-in reflector enables the lamp to be made relatively small while the lens system gives an optimum illuminated area of approximately 3 X 5 A inches with a sharp outline.

in order to replace the light 64 all that is necessary is to remove the fin assembly nuts 59 of the three

convection fin assemblies

48, 48a, 48b. The complete front fin assembly comprising the fins 52a 52f, the associated spacers 54 and the sleeves 51 of the three fin assemblies, isthen drawn away from the rods 47 carrying the light 64 with it. The bulb of the light 64 can then be replaced and reassembled. Alternatively the rear fin assembly can be removed to give access to the back of the light 64 by removing the three rear fin assembly units 60 and withdrawing the fins 53a 53c and the associated spacers 54 and sleeves 51.

It will be seen from the above that the structure of the dental operating lamp of the present invention provides quick and easy access to the light 64 for servicing and replacement, that side dazzle from the light emitted is eliminated or at least substantially reduced and that the heat generated by the bulb is efficiently dissipated by the convection currents which flow freely through the lamp in the region of the bulb regardless of the position in which the lamp is placed.

Further minor modifications can be made to the above described embodiment without departing from the spirit and scope of the invention which is best described in the following claims.

What we claim is:

l. A lamp for use as an operating lamp, comprising an annular frame, a support, means for mounting the frame of the lamp on said support, a light source and lens system mounted on the annular frame with the op tical axis of the lens system generally aligned with the axis of the frame, a plurality of annular convection fins removably mounted on the frame in spaced relationship so as to surround the light source and allow an uninterrupted passage for convection currents in substantially all radial directions from the light source, wherein the convection fins are dished so as to form a shade for the light source without impeding the air flow around the light source, wherein a plurality of longitudinal members project from each side of the frame in parallel with the axis-of the frame and a plurality of the said convection fins are removably mounted on the members on each side of the frame.

2. A lamp as claimed in claim 1, wherein the convection fins on each side of the annular frame are mounted on the longitudinal members so as to be removable as a single unit to give easy access to the front or rear of the lamp respectively.

3. A lamp as claimed in claim 2, wherein the longitudinal members comprise rods extending through the annular frame so as to project from each side thereof, a sleeve is slidably mounted on each end of each rod and the convection fins are mounted on the sleeves so as to be removable with the sleeves.

4. A lamp as claimed in claim 3, wherein each convection fin comprises a substantially flat annular base and a dished annular flange projecting outwardly therefrom.

5. A lamp as claimed in claim 4, wherein the base of each convection fin is formed with a plurality of first apertures to receive the sleeves on which each fin is mounted.

6. A lamp as claimed in claim 5, wherein the rear cone has a base formed with a plurality of second apertures for the passages of convection currents therethrough.

7. A lamp as claimed in claim 6 wherein the convection fins are separated by tubular spacers slidably mounted on the sleeves.

8. A lamp as claimed in claim 7, wherein three angularly spaced longitudinal members project from each side of the annular frame.

9. A lamp as claimed in claim 1, wherein said means for mounting the lamp on said support comprises a tubular arrn forming a continuous conduit and includes two joints allowing the lamp to be rotated through at least 330 about each of the two mutually perpendicular axes.

10. A lamp as claimed in claim 9, wherein thesaid mutually perpendicular axes are both perpendicular to and pass through the optical axis of the lamp,-

1 1. A lamp as claimed in claim 10, wherein the tubular arm includes a tubular spigot which projects radially from the annular frame and is mounted on the outer end of an intermediate arm portion so as to be rotatable, relative thereto, about its own axis through at least 330.

12. A lamp as claimed in claim 11, wherein the intermediate arm portion is mounted on a bush so as-to be rotatable, through at least 330 about an axis perpendicular to the axis of the spigot and to the axis of the lamp.

13. A lamp as claimed in claim 12, wherein the inter- I mediate arm portion is cranked, whereby the axis about which the intermediate arm portion is rotatable is offset from the point at which the spigot is joined to the intermediate arm portion.

Claims

1. A lamp for use as an operating lamp, comprising an annular frame, a support, means for mounting the frame of the lamp on said support, a light source and lens system mounted on the annular frame with the optical axis of the lens system generally aligned with the axis of the frame, a plurality of annular convection fins removably mounted on the frame in spaced relationship so as to surround the light source and allow an uninterrupted passage for convection currents in substantially all radial directions from the light source, wherein the convection fins are dished so as to form a shade for the light source without impeding the air flow around the light source, wherein a plurality of longitudinal members project from each side of the frame in parallel with the axis of the frame and a plurality of the said convection fins are removably mounted on the members on each side of the frame.

9. A lamp as claimed in claim 1, wherein said means for mounting the lamp on said support comprises a tubular arm forming a continuous conduit and includes two joints allowing the lamp to be rotated through at least 330* about each of the two mutually perpendicular axes.

10. A lamp as claimed in claim 9, wherein the said mutually perpendicular axes are both perpendicular to and pass through the optical axis of the lamp.

11. A lamp as claimed in claim 10, wherein the tubular arm includes a tubular spigot which projects radially from the annular frame and is mounted on the outer end of an intermediate arm portion so as to be rotatable, relative thereto, about its own axis through at least 330*.

12. A lamp as claimed in claim 11, wherein the intermediate arm portion is mounted on a bush so as to be rotatable, through at least 330* about an axis perpendicular to the axis of the spigot and to the axis of the lamp.

13. A lamp as claimed in claim 12, wherein the intermediate arm portion is cranked, whereby the axis about which the intermediate arm portion is rotatable is offset from the point at which the spigot is joined to the intermediate arm portion.