The invention relates to a task light and more particularly to an operating room light that incorporates LEDs.
Surgical treatment lights employed in rapidly deployable temporary field hospitals typically comprise a single incandescent or halogen light source. These medical treatment tights are typically required to withstand hot ambient temperatures of up to 130 degrees Fahrenheit and other harsh conditions. Preferred design criteria for such lights include light weight, simple operation, reduced heat emission to avoid drying living tissue or burning the user, sterile replaceable handling levers, longevity particularly reduced need for spare parts including replacement bulbs and rapid assembly and deployment into a compact easily supportable structure from a portable kit.
Typical non-portable operating room lighting comprises large multiple strong light sources which have heavy structural support systems that make them capable of adjustable positioning to avoid and fill shadows and are typically capable of wide lateral positioning to minimize shadowing attributable to the surgeons head. This type of heavy structure is impractical in rapidly deployable temporary field hospitals which provide first line care in a Forward Resuscitative Surgery System (FRSS) described herein.
In one aspect, the invention is directed to a treatment light that is adapted for portable use by way of its relatively low weight and/or relatively small size, and wherein the light incorporates LEDs into multiple light sources which are spaced from each other.
In another aspect, the invention is directed to a treatment light that is adapted for portable use by way of its relatively low weight and/or relatively small size, and wherein the light incorporates at least two light sources which are separated by a space which can accommodate a user's head and which remains at a temperature which is less than 130 degrees Fahrenheit under steady state conditions with ambient temperature at 72 degrees Fahrenheit.
In another aspect, the invention is directed to a light with a handle mount that is changeable so that the light can accommodate a plurality of handles which have different mounting means (eg. one handle may have a particular type of thread, while another may have a different type of thread or may have a non-thread type of mounting means, such as, for example, a bayonet fitting [is this shown in the drawing?].
In another aspect, the invention is directed to a portable treatment light kit comprising a support structure having at least two light source support portions, each support portion adapted to be connected to a light source comprising a plurality of LEDs; at least two light sources each comprising a plurality of LEDs; the at least two of the light sources adapted to be readily adjusted to a position which defines at least one space between them for placement of a user's head in substantial lateral alignment therebetween when in use; each light source operatively associated with a heat elimination system capable of drawing heat away from potential contact surfaces with the user's head when positioned in the space.
In another aspect, the invention is directed to a portable treatment light that has a support structure having at least two (and in some embodiments three or more), support portions (points of attachment for light sources to be described) that are spaced apart (and in some embodiments extending or radiating from a junction in spaced apart fashion), each support portion being operatively attached to a light source having a plurality of LEDs, the light sources capable of being fixedly positioned or already pre-positioned (in virtue the spatial arrangement of the support portions to which they are attached) to define at least one space between them for placement of a user's head in lateral alignment (though not necessarily in vertical alignment) between them, when in use, each light source operatively associated with a heat transfer system for drawing heat away from the points of potential contact with the user's head when positioned in the space. By being positioned in proximity to the user's head, in approximate lateral alignment with the middle of the space and in relative close proximity to the user's head (also more closely aligned in a vertical position relative to the placement in a typical permanent operating room), the support structure itself provides a reference point to position the LED light sources so that shadowing is well reduced and the available output is well used. Using the light in this fashion is made possible by a heat reduction system that prevents burning to the touch. Importantly this combination of features has been found to be compatible with a portable lighting system, that employs LED lights which are generally longer-lasting than conventional incandescent bulbs, and is compact, rapidly assembled, easily used and rapidly adjusted.
Accordingly, in one embodiment, the invention is directed to a support structure that defines a position for the light sources relative to the head that is both adapted to avoid shadowing while also according well with a selected light focusing material and a selected distance at which the light is most needed. Optionally, this distance being somewhat longer that the distance between the user's eyes and the task surface, is within 30 to 48 inch range, optionally within the 33 to 45 inch distance range, optionally within the 36 to 42 inch range, optionally approximately one meter. The handle is optionally closely available at the center of the light sources to reposition the light to easily maintain the positioning demarcated by the positioning of the light next to the head and that accords with the heat reduction capability and the characteristics of the LED light focusing material and the watt output of the LEDs. The portable treatment light is optionally used with a flexible arm that is designed to support 15 pounds and optionally the light is therefore less than 15 pounds, optionally less than 10 pounds, optionally less than 5 pounds, optionally less than 3 pounds. The heat reduction capability is optionally selected to accord with a contact surface temperature of optionally less than 124 degrees Fahrenheit, optionally less than 120 degrees Fahrenheit, optionally less than 110 degrees Fahrenheit, optionally no greater than 100 degrees Fahrenheit. Accordingly, in a general aspect the portable treatment light of the invention has spaced LED light sources that demarcate a space for the user's head that accords with pre-selected heat dissipating and focal distance characteristics.
Accordingly, in one embodiment, the invention is directed to a portable treatment light comprising:
at least three support members radiating from a hub;
each support member supporting a light source positioned distally from the hub comprising a plurality of LED units;
each of the three support members defining at least one space between it and a respective adjacent support member for placement of a user's head between two light sources supported by two adjacent support members, when in use;
each light source operatively associated to a heat dissipater for drawing heat away from the user's head when the user's head is positioned in the space.
In another aspect, the invention is directed to a vast improvement in compact portable surgical light technology by employing long-lasting light emitting diodes as a light source.
Accordingly, in one aspect, the invention is directed to a treatment light comprising a support member having at least two light source support portions; each support portion adapted to be operatively connected a light source; each light source comprising one or more LEDs, particularly a plurality of LEDs associated with a focusing material which focuses the LED emitted lights into cones, the at least two light sources adapted to be fixed at spaced apart positions proximate to either side of the head of a user, the support members defining a space for positioning the head of the user next to and potentially in between the at least two light sources, and wherein those positions focus the respective beams of light generated by the light sources on a task surface at a distance typical of the distance between the user's head and the treatment area (approximately one meter for surgical applications in field hospitals) each light source operatively associated with a heat dissipation system capable of drawing heat away from potential contact surfaces with the head of the user when positioned in the space next to the user. Preferably, the potential contact surfaces have a steady state temperature of no greater than 120 degrees Fahrenheit when tested at an ambient temperature of 72 degrees Fahrenheit. According to one embodiment of the invention, the potential contact surfaces are no hotter than 100 degrees Fahrenheit despite generating a cumulative output of 60 to 65 watts of power. We have also found that a support member that fixes the positions of the at least two and optionally three LED-based light sources into a compact spherical area (obviating the need for a weight-adding variable positioning structure for adjusting the positions of light sources relative to one another) is able to eliminate shadows in a fashion akin to more powerful widely spaced and distantly positioned light sources without diminishing necessary illumination or generating contact surfaces that could burn the user or adversely affects the patient tissues. Accordingly we have found that focused LED light technology (including attendant advantages of the light colour variations that enhance this technology (combinations of 3500 and 5500 degree Kelvin diodes)) can be employed outside optimal permanent hospital settings (air conditioned, roomy, spacious, weight supporting, power abundant) and is compatible with the daunting rigorous demands of rapidly deployable field hospitals and other settings with comparable power, space, ambient temperature, weight supporting or portability constraints. Weight and size constraints may vary and may be set so that the task light (with support arm and base) not weigh more than 8.2 Kg (18 lbs) without its shipping case or optionally not weigh more than 16 Kg (35 lbs) in its shipping case or that the task light fit into a packing case 1220×432×87 mm (48″×17″×7″) or that any combination of these requirement be applicable. Optionally, the support arm of the task light has a range of adjustability that may include 1 m height adjustment, and/or 0.75 m radial adjustment and/or 30 degrees head angle adjustment.
Other aspects and features of the present invention will become apparent, to those ordinarily skilled in the art, upon review of the following description of the specific embodiments of the invention.
For a better understanding of the present invention, and to show more clearly how it may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, which illustrate aspects of embodiments of the present invention and in which:
a is a magnified exploded perspective view of a heat dissipation device from the task light shown in
Reference is made to
The task light 10 includes a plurality of light sources 12, including in the exemplary embodiment shown in
In one aspect, the task light 10 is advantageous in that it permits a user 16 to position it substantially at head level in a position such that a light source 12 is on one side of the head (shown at 18) of the user 16 and another light source 12 is on the other side of the head 18 of the user 16, while releasing a reduced amount of heat to the user 16 relative to some prior art lights. This position may be advantageous to the user 16 in that it permits the light 10 to be positioned dose to the work surface, shown at 19, which provides increased brightness at the work surface 19.
The light sources 12 may each be made up of one or more light elements 20 which may be, for example, light emitting diodes (LEDs) 20. For example, each light source 12 may contain seven LEDs 20. The LEDs 20 may be arranged in an offset pattern, which permits relatively tighter clustering, as shown in
The LEDs 20 may include one or more first LEDs 20a and one or more second LEDs 20b. The first LEDs 20a are adapted to emit light at a first colour temperature eg. 5500 degrees Kelvin, and the second LEDs 20b are adapted to emit light at a second colour temperature, eg. 3500 degrees Kelvin. For example, in the embodiment shown in
Each light source 12 may be controlled in any suitable way. For example, the light 10 may have a main power switch 62 which controls power to the light 10 from a power source (not shown). The light 10 may further include a second LED power switch 64 which may be positionable in a first position and a second position. In the first position, the second LED power switch 64 operates the second LEDs 20b at a selected low level of power. In the second position, the second LED power switch 64 operates the second LEDs 20b at a selected low level of power. Regardless of the position of the second LED power switch 64 the one or more first LEDs 10a may operate at high power. For example, the first LEDs 20a may have a colour temperature of 5500 degrees Kelvin and the second LEDs 20b may have a colour temperature of 3500 degrees Kelvin.
The light made up of the first LEDs 20a in combination with the second LEDs 20b may have a colour temperature of approximately 5000 when the second LED power switch 64 is in the first position and a colour temperature of approximately 4300 degrees Kelvin when the second LED power switch 64 is in the second position. Other control logic may alternatively be used however instead of the aforementioned. Generally speaking the color temperature is adjusted by means of varying the pulse frequency of white and amber LEDs. Optionally, the whites may be at full power consistently and the ambers may have two settings one at full power (frequency) another which slow their pulse down (by lowering current) so that there is less amber light in the mix.
For the light 10 shown in
The output power of the light sources 12 may be expressed also in terms of wattage. Each of the LEDs 20 that make up the light sources 12 may be a 3 W LED.
Referring to
The heat transfer member 34 transfers heat away from the LEDs 20 and towards a plurality of a plurality of heat dissipation devices 36 that are in thermal connection therewith. The thermal dissipation devices 36 transfer heat from the heat transfer member 34 into the environment. The heat transfer member 34 may be made from any suitably thermally conductive material such as a metallic material, such as, for example, Aluminum, which may be anodized.
The heat transfer member 34 includes a first surface 38a and an opposing second surface 38b. The first surface 38a is the surface that contacts the heat conduction surfaces 30 of the LEDs 20.
As shown in
The heat dissipation device 36b may contact the heat transfer member 34 at a point that is spaced from the light source 12. For example, the heat dissipation device 36b may contact the heat transfer member 34 proximate a second end, shown at 34b. Thus, at least in part, heat is transferred away from the LEDs 20 along the length of the heat transfer member 34, ie. along the plane of the heat transfer member 34.
Referring to
The fan 42 may be configured to draw air from the environment and to blow the air through the extensions 46 and back out to the environment. Alternatively, the fan 42 may be configured to draw air in from the environment through the extensions 46 and then through the fan itself 42 and then back out to the environment.
The heat dissipation devices 36b may be similar to the heat dissipation devices 36a, and may also each include a heat sink 48 and a fan 50. The heat sinks 48 and fans 50 may be similar in structure to the heat sinks 40 and the fans 42, however the heat sinks 48 and fans 50 may be sized to deal with the quantity of heat that reaches them via the heat transfer member 34, which may be different than the amount of heat that reaches the heat dissipations devices 36a from the light sources 12.
The heat transfer members 34 may all be integrally connected to each other. For example, they may extend outwardly from a common hub 52. As a result, the heat transfer members 34 and hub 52 are thermally connected together as part of a single integral member 54 and are therefore able to balance out to some degree any heat generation differences that might exist between the light sources 12. For example, if one of the light sources, for example 12a, generates more heat than the other heat sources, 12b and 12c in this example, or if the light source (12a in this example) is unable to dissipate heat as effectively as the others, then excess heat will be transferred through the integral member 54 towards the heat dissipation devices 36 associated with the other light sources 12. In this way, an increase in the temperature of one of the light sources 12 is at least partially dampened out by increasing the amount of heat that is dissipated by at least several of the heat dissipation devices 36.
As a result of the thermal connection between all of the heat transfer members 34, the heat dissipation devices 36b may be replaced by a single heat dissipation device, which is sized to dissipate heat transferred thereto from all of the heat transfer members 34.
To reduce the risk of damage to the LEDs 20 as a result of temperature, a thermistor may be included to sense a temperatures associated with each light source, so that the thermistor switches off its associated light source if the sensed temperature exceeds a selected limit. The thermistor may be in contact with the heat transfer member 34 proximate its first end 34a to provide temperature information regarding the light source 12 positioned at the first end 34a.
The integral heat balancing member 54 may act as the structural support 14 that supports the light sources and heat dissipation devices 36. The configuration of the integral heat balancing member 54 may be as shown in
By acting as a structural support and a heat transfer member, the member 54 provides two functions simultaneously and thus serves to reduce the overall weight of the device. Additionally, the shape of the member 54 is such that it provides sufficient thermal conductivity for removing heat from the light sources 12, but omits portions that would otherwise fill the spaces between the arms 34 since they do not transfer heat directly from one of the light sources 12 to one of the heat dissipation devices 36b. This further reduces the overall weight of the light 10. As a result of these and possibly other measures, the light 10 may weigh less than 3 lbs and may possibly weigh less than 2.5 lbs. As a result, the light 10 is adapted for use in portable medical care facilities, such as those facilities which are erectable in battle by the military to quickly provide care for an injured person. Such a facility is sometimes referred to as a Forward Resuscitative Surgery System (FRSS). Typically prior art lights which are used in such facilities have a single light source, which is not an LED.
As shown in
As a result, the user 16 can position the light 10 at head level above the work surface 19 (
By using LEDs 20 instead of other lighting elements such as halogen lighting elements, less heat is generated at each light source 12 relative to the amount of light provided. This permits a relatively greater amount of illumination to be provided while keeping the temperature at an acceptable level for the user 16. Where ambient temperature is about 72 degrees Fahrenheit, the temperature of the housing elements 68, 70 and 72 that are shown around the light sources 12 and the first heat dissipation devices 36a can be kept below 130 degrees Fahrenheit. Optionally, the temperature of the contact surfaces of the housing elements 68, 70 and 72 can be kept below 100 degrees Fahrenheit. These temperatures apply in steady state conditions, which may occur within approximately 20 minutes of turning the light 10 on.
In addition to the relatively cool temperatures of the contact surfaces of the housings 68, 70 and 72, the light emitted by the LEDs has a relatively low component in the infra-red range and as a result, the LEDs do not emit significant quantities of heat. As a result, the tissues of the patient being illuminated are not subject to damage from drying out as a result of being illuminated by the light 10.
In addition to the heat transfer element 34 being configured to transfer heat from the light sources 12 to the heat dissipation units 36a and 36b, the heat transfer element 34 releases heat by itself into the environment. This release of heat is further assisted by having significant fraction of the surface area of the heat transfer member 34 exposed directly to the environment.
The light sources 12 may each be positioned at a selected angle with respect to the general plane of the light 10 so that their emitted light converges at a selected distance from the plane of the light 10. The plane of the light 10 is, in the exemplary embodiment shown in
A light-directing element 66 may be provided which receives emitted light from the LEDs 20 and provides a selected cone angle to the emitted light. The cone angle may be, for example, 6 degrees. With this cone angle, the emitted light from the light sources 12 forms a generally circular relatively uniformly bright area on the work surface of about 8 inches in diameter, optionally about 5 inches.
The light sources 12 may be positioned at a selected radius from the centre of the light 10 so that the light coming from the three light sources 12 converges at a distance of approximately 1 m from the plane of the hub 52. For example, the light sources 12 may be positioned within a radius (or distance in embodiments wherein the light sources 12 are not positioned on a circular arc) of approximately 6.2 inches from the center of the light 10. Generally, the light sources 12 may be positioned within a radius that is within a range of about 5.2 to about 7.2 inches from the center of the light 10, while still producing a generally circular disc having a diameter of about 8 inches.
The selected distance from the plane of the light 10 at which the emitted light converges from the light sources 12 may be selected so that it corresponds generally to the distance between the level of the head 18 of a typical user 16 and the typical level of the work surface 19.
Reference is made to
A housing 80 may be provided over the heat dissipation devices 36b, the main circuit board 76 and the switches 62 and 64. The housing 80, and the housings 68, 70 and 72 may all be made from a suitable polymeric material which is relatively thermally non-conductive.
Variations in cone angle and converging distance are contemplated.
Referring to
Reference is made to
A light in accordance with an embodiment of the invention may have as few as two light sources. Alternatively it may have five or more light sources.
The term “opposite sides of the head” is used to define positions of the lights sources relative to the head of the user and is understood to mean that the support structure together with the light sources define a notch-like space for head placement that is large and deep enough for the user to position his/her head between the light sources to an extent that the light sources are proximate to the respective coronal sutures on either side of the head.
While the above description provides example embodiments, it will be appreciated that the present invention is susceptible to modification and change without departing from the fair meaning and scope of the accompanying claims. Accordingly, what has been described is merely illustrative of the application of aspects of embodiments of the invention. Numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/CA2007/001480 | 8/23/2007 | WO | 00 | 4/28/2010 |
Number | Date | Country | |
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60823504 | Aug 2006 | US |