EP2207994B1 - Led light for operating rooms - Google Patents

Description

The invention relates to an operating room (OP) luminaire with a luminaire housing, a plurality of LED illumination modules which can be adjusted for focusing and a focusing unit designed as a linear transmission for focusing the illumination modules.

Preferably, the lighting modules are satellite-like hinged to a central luminaire body. The luminaire base body defines a working plane of the surgical light around which the illumination modules are pivotable. Such a lamp provides in a surgical room of a hospital focusable on different foci light cone with a particularly high luminance in the focal point.

The document EP-1722156 represents such a surgical light according to the preamble of claim 1.

Since different operations have different sizes of surgical field, it is necessary to be able to adjust the operating field size of the operating field lamp's luminaire field diameter and focus it in order to avoid glare from the operator due to reflections of the surrounding tissue.

The pivoting of the illumination modules for focusing on different luminaire field diameter is usually carried out by an electric motor via servo motors. These electric motors are costly and prone to failure. Other known surgical lights include a central light, which is designed to focus different light field diameter can. This focusing is done either by adjusting the bulb or by adjusting the reflector, which is arranged behind the rear of the lamp.

The luminaire base body with the satellite bodies pivotally attached thereto, which comprise the LEDs with a surrounding luminaire housing, are usually attached to the ceiling or to the developer via a cardan suspension in the case of existing surgical luminaires. Movement of the relatively heavy satellites also alters the center of gravity of the entire luminaire, which may cause undesired rotation of the luminaire on the gimbal.

Based on the above-mentioned prior art, the object is at least partially to avoid the aforementioned disadvantages and to provide an operating light that allows cost-effective and interference-free focusing, in particular without causing an undesirable adjustment to the suspension.

According to the invention this object is achieved in that the lighting modules comprise a pivotally mounted on the lamp housing pivot plate with the LEDs arranged thereon.

As a result of the construction according to the invention, only the pivot plate mounted pivotably in the luminaire housing must now be adjusted by the focusing unit or adjusting unit without moving the heavy luminaire housing itself, which could cause a change in the center of gravity of the luminaire. In contrast to the prior art, the entire luminaire housing is thus rigid and has no pivotable on the central portion star-projecting satellites. Instead, one or more pivot plates are preferably mounted in radially projecting from the center of the light arms.

Usually, the pivot plates are mounted on pivot axes. The pivot axes preferably extend transversely to an axis running through the center of the surgical light, that is to say an axis extending radially outward from the center to the outside.

Along this radially star-shaped protruding axes preferably also extend one or more pivot rods for transmitting the translational movement of a height-adjustable by the rotary handle central element to which the pivot axes are pivotally mounted. These acting on the principle of operation of a rocker and mounted on a rocking or pivoting pivot rods transmit the lifting and lowering movement of the central element on the pivot plates for focusing the LED assemblies.

At the tilting points for the pivot rods bearing blocks can be provided, which allow the simultaneous execution of a translational and rotational movement. In the preferred embodiment, these bearing blocks comprise a ball joint rotatably received in a receiving element with a central passage opening for the pivot rod. By means of these swivel rods circumferentially receiving ball joints, the pivot rods can simultaneously perform their pivotal movement, and also perform a translational motion in the ball joints acting as plain bearings. Preferably, the balls of the ball joint made of a plastic with good sliding properties to realize a displacement of the rod and an angular adjustment.

According to the invention, a plurality of illumination modules may be provided in a plurality of arms protruding radially from the center of the surgical light, each of which is pivotally mounted on a pivot plate which is adjustable by the linear transmission. In principle, it is possible that the individual pivot plates are independently adjustable; However, the preferred embodiment provides that the pivot plates of the individual LED arrays are uniformly focused by uniform rotation of the focusing. This is done Setting all lighting modules thus synchronous.

Another aspect of the invention relates to the formation of the collimator lens. Collimator lenses are used to focus the light emitted by LEDs, especially for power LEDs. In the case of existing collimator lenses, there is the problem that blue light is generated in the peripheral edge region, which leads to an undesired change of the light and thus of the color rendering index in the surgical area, so that unnatural color impressions can occur at the surgical wound.

Based on this prior art, the invention further has the object to avoid this disadvantage, at least partially, and to provide a collimator lens which has little or no undesirable in the peripheral edge region, which interferes with the color rendering index.

This object is achieved in that the radius of curvature of the outer surface of the collimator lens, the height of the collimator lens, the light entry surface, the size and geometric design of the light exit surface and the geometry of the light exit surface are coordinated so that the blue light in the edge region of the lens by mixing is avoided in a central area. Furthermore, the light exit surface is provided with a specific structured surface for generating a specific refraction of light. The lateral surface is preferably curved convexly slightly outward.

In a further development, the collimator lens is additionally designed to obtain a light distribution curve having a half-power angle in a range of ± 2 to 2.5 degrees, preferably ± 2.0 degrees and the ten-value angle a range of 4.0 to 5.0 degrees, preferably 4.0 degrees.

To avoid stray light, each collimator lens is inserted during installation in a cup-shaped holder arranged above the LED, which light entry through a lower Opening and a light exit through the light exit surface of the collimator lens at the front end allows. Preferably, this pot-shaped holder made of a black plastic and is designed as an injection molded part. According to the invention, each collimator lens is placed in front of an LED in such a holder. It is usual that the holder is glued with a two-sided tape in front of the LED.

A third aspect of the invention is concerned with the problem of achieving the most homogeneous possible illumination with regard to the color distribution in the surgical area. In principle, it is desirable for the light generated by the LEDs to have the highest possible color rendering index, which is as similar as possible to natural light or sunlight, since this does not change the color impression of the wound. However, existing LEDs produce a light that has a relatively high proportion of white light, which can lead to an undesired color impression of the wound.

Another object of the invention is therefore also to at least partially avoid these disadvantages and to provide a luminaire which enables the use of LEDs in a surgical light to achieve the highest possible color rendering index.

This object is essentially achieved in that different LED arrangements of individual LEDs are provided which have different arrangements of colored LEDs. To achieve the most homogeneous possible illumination in terms of color distribution, green LEDs and red LEDs are preferably used in addition to white LEDs. It has proven to be particularly useful to combine an embodiment with the colored LEDs more in the edge region of the LED array with a further embodiment with the colored LEDs more in the central inner region so that the colors in focus to achieve a color rendering index greater Overlay 90, preferably to achieve a Color rendering index greater than 95 in the entire focus area. The different arrangements ensure a thorough mixing of the individual colors to improve the color rendering index. In addition, the arrangement according to the invention avoids colored shadows.

A preferred further development provides that the differently colored LEDs are also energized differently. To comply with the low voltage directive, it is advantageous that the connected value of several LEDs arranged in series has a voltage of max. Does not exceed 50 volts. Particularly advantageous is the operation of two circuits for white LEDs, a circuit for red LEDs and a circuit for green LEDs. The best results were obtained when the red circuit is operated with about 40-50% of the current of the white and green circuits.

In the development, it has also been shown that by using a current dimming instead of the known in the prior art pulse width modulation electromagnetic interference can be largely avoided, which can lead to image interference in image recording systems. As a result of the current dimming according to the invention, the recording power of image recording systems can thus be considerably improved.

Fig. 1

eine Draufsicht der OP-Leuchte mit vier Armen;

Fig. 2

einen Längsschnitt entlang einer der Arme der OP-Leuchte gemäß Figur 1;

Fig. 3

eine Seitenansicht einer erfindungsgemäßen Collimatorlinse;

Fig. 4

eine Draufsicht im Teilschnitt auf das Lichteintrittsende der Collimatorlinse gemäß Figur 3;

Fig. 5

eine Draufsicht im Teilschnitt auf das Lichtaustrittsende der Collimatorlinse gemäß Fig. 3;

Fig. 6

eine erste Ausführungsform einer LED-Anordnung in einem zweiten und vierten Arm der OP-Leuchte und

Fig. 7

eine zweite Ausführungsform einer LED-Anordnung in einem ersten und dritten Arm der OP-Leuchte;

Further details, advantages and features of the invention can be taken from the following part of the description in which a preferred embodiment of the surgical light according to the invention is explained in more detail. Show it:

Fig. 1

a top view of the operating light with four arms;

Fig. 2

a longitudinal section along one of the arms of the surgical light according to FIG. 1 ;

Fig. 3

a side view of a collimator lens according to the invention;

Fig. 4

a plan view in partial section on the light entry end according to the collimator lens FIG. 3 ;

Fig. 5

a plan view in partial section on the light exit end of the collimator lens according to Fig. 3 ;

Fig. 6

a first embodiment of an LED assembly in a second and fourth arm of the surgical light and

Fig. 7

a second embodiment of an LED assembly in a first and third arm of the surgical light;

Accordingly, the surgical light of the invention consists of a lamp housing 2 with a central region 4, of which a first arm 6, a second arm 8, a third arm 10 and a fourth arm 12 star-shaped at an angle of approximately 45 ° from the center of the central area 4. On the undersides of the outer ends of these arms 6,8,10,12 circular pivot plates 32 for LED assemblies 34 are pivotally mounted on pivot axes 42 for focusing.

The in the cut in Figures 2 Focusing unit of the surgical light shown enlarged consists of a rotary handle 14 which is rotatably arranged at the bottom in the center of the central region 4. By rotation of this rotary handle 14 a recorded in the rotary handle 14 in a locking sleeve 16, internal spindle 18 is driven. Depending on the direction of rotation, this spindle 18 raises or lowers an adjustment unit designed as an adjustment cross 20. This Verstellkreuz 20 consists of a cylindrical lower portion 22, at its widened upper end four radially projecting support arms 24 are provided, of which two support arms 24 are arranged in pairs collinear with each other and with the other pair of collinear support arms including an angle of 90 Cross degrees. Each support arm 24 flattened on both sides has a circular passage opening 26 at its radially outer end. At this passage opening 26 in the present case four clevises 28 are pivotally mounted via a respective pin. The clevis 28 are at their outer, free Ends provided with receiving sockets of swivel rods 30. The receiving bushes comprise internal threads into which correspondingly formed threads of the inner ends of the pivot rods 30 are screwed. These swivel rods 30 form the swiveling lever construction according to the invention for swiveling pivoting elements formed as swivel plates 32 with LED arrangements 34 arranged thereon, which in the present case each comprise 37 LEDs of different colors.

Each pivot rod 30 is pivotally connected at its inner end with a clevis 28 to a support arm 24 of the Verstellkreuzes 20 and at its outer end pivotally connected to a pivot plate 32. Approximately in the middle of the pivot rods 30 are each guided by a ball joint 36. These ball joints 36 each consist of an annular, outer retaining element 38 with fastening tabs mounted on the upper side and mounted on the lamp housing and a spherical sliding bearing 40 inserted into the annular retaining element whose outer diameter corresponds to the inner diameter of the retaining element 38 and which has a central passage opening in the size of the outer diameter the pivot rod 30 has. The pivot rod 30 penetrates this central passage opening. When height adjustment of the Verstellkreuzes 20 by turning the rotary handle 14, a pivoting of the pivot rods 30 is effected about the radially projecting support arms 24. By the bearing of the pivot rods 30 in the plain bearings 40 a Kipphebelkonstruktion is realized, which thus causes a pivoting of the pivot plates 32 about the arranged below this pivot axes 42. In this way, the LED arrays 34 positioned on the pivot plates 32 are all focusable simultaneously to the desired focus by performing a rotational movement on the rotary handle 14. The invention thus represents a particularly simple, inexpensive and robust adjusting means in comparison to the prior art.

Like from the Figures 2 and 6 and 7 it can be seen are present four satellite arranged around the central region 4 LED assemblies 34 are provided, each of which comprises a total of 37 LEDs each having a collimator lens 50 associated with each LED.

Two pairs of diametrically opposite arms in the arms 6, 8, 10, 12 opposite LED assemblies 34 have the same arrangements of color-coded LEDs. In the present case, green LEDs 52 and red LEDs 54 are used in various positions in addition to white LEDs 56 to achieve the most homogeneous possible illumination with respect to the color distribution, namely in one embodiment according to FIG Fig. 6 with the colored LEDs more in the outer area of the LED array 34 and in another embodiment according to FIG Fig. 7 with the colored LEDs more in the central region of the LED assembly 34. The respective same LED arrays 34 are arranged mirror-symmetrically diametrically opposite to the arms 6, 8, 10 and 12 of the surgical light. At a distance of about 1 meter from the luminaire in focus, the superimposition of the colors red, green and white results in a homogeneous luminous field with a color rendering index greater than 95 in the entire focus range. The presently selected arrangement of six green LEDs 52 and six red LEDs 54 in addition to 25 white LEDs 56 produces the most homogeneous possible illumination with regard to the color distribution in the luminaire field. Furthermore, this arrangement almost completely avoids colored shadows, which is essential for a clear representation of the wound in the surgical area.

This color rendering index is also achieved by the different energization of different colored LEDs. The low-voltage directive is observed in the operation of the lamp according to the invention characterized in that each circle of several LEDs receives a maximum of 50 volts of voltage. Two white circles, one red circle and one green circle are operated by one ECG each. The energization is carried out so that the red circle is operated with about 40 to 50% of the current of the white and green circles.

By using this current dimming instead of the usual in the prior art pulse width modulation caused by electromagnetic interference image interference in modern imaging systems are avoided. According to the invention, the recording power of image recording systems is thus significantly improved.

The FIGS. 3 to 5 show a collimator lens 50, which is also called rectifying lens and is placed in the beam direction on the individual LEDs to focus the light emitted by the LEDs light. These collimator lenses 50 assume the function of the primary lens in the surgical light. These working with the principle of total reflection collimator lenses 50 are preferably formed as PMMA - injection molded body with the geometry of a circular truncated cone, an outer and circumferentially extending outer surface 58, a lower mounting position in the light entrance surface 60 with a recess 62 for the LED with attached collimator lens 50 and a in the installed position upper light exit surface 64, whose diameter in the ratio 3.7: 1 is greater than the light entrance surface 62. According to the invention, the lateral surface 58 is slightly convex. The interplay of the radii of curvature of the outer lateral surface 58, the size of the light entry surface 60, the size of the light exit surface 64, the height of the collimator lens 50 and the design of the surface of the light exit surface 64, a light distribution curve is achieved, which has a half-value angle of in the range of +/- 2.0 to 2.5 degrees, preferably +/- 2.0 degrees and the ten-value angle has a range of 4.0 to 5.0 degrees, preferably 4.0 degrees.

• Durchmesser der Lichteintrittsfläche / Durchmesser der Lichtaustrittsfläche: 1 : 1,7.
• Höhe der Linse / Durchmesser der Lichtaustrittsfläche: 1 : 1,7

The light exit surface 64 is initially convexly curved from the outside to the inside and then merges into a planar center 66, which in the present case is about 1: 1.6 times the total diameter of the light exit surface 64. By a corrugation on the light exit surface 64 is made of The prior art avoids and criticizes blue light in the edge region of each collimator lens 50 by mixing it centrally. To achieve the effects of the invention the dimensions are as follows:

• Diameter of the light entry surface / diameter of the light exit surface: 1: 1.7.
• Height of the lens / diameter of the light exit surface: 1: 1.7

The dimensions in a preferred embodiment are as follows: Diameter of the light entry surface: 7.10 mm Diameter of the light exit surface: 26.50 mm Diameter of the planar center of the light exit surface: 16.21 mm Height of the lens: 15.85 mm Height of the recess at the light entry surface: 5.12 mm Radius of curvature of the lateral surface: 5.96 mm

Each of the collimator lenses 50 in the LED array 34 is mounted in an upwardly open, cup-shaped holder 68 on the pivot plate 32 above the LEDs. This holder 68 surrounds the collimator lens 50 circumferentially except for the light exit surface 64. The light irradiated on the underside in an opening of the holder 68 of the respective LED is collimated by the collimator lens 50 and reducing the scattered light emitted by the consisting of a black plastic holder 68 at the light exit surface 64.

The in the FIGS. 6 and 7 illustrated various embodiments of LED assemblies 34 with different arrangements of color LEDs, of which in the present case two identical arrangements 34 diametrically opposite in the arms 6, 8, 10, 12 are arranged, complement each other by overlaying the colors in focus to achieve a Homogeneous luminous field with a high color rendering index greater than 90, preferably greater than 95. Of course, this result can also be achieved by several arms with corresponding LED arrays 34 by superimposing the colors emitted by the LEDs.

The pivot plates each have on one side radially projecting connector 70 with which the LED assemblies 34 are connected to the ECGs of the lamp and to utilities in the central region 4 of the lamp.

After placing all the function of primary lenses satisfying collimator lenses 50 on the LEDs in addition, a housing cover 72 with an opening and a housing lens 74 used in this opening. This housing lens 74 takes over the function of the secondary lens and focuses the individual emitted via the LEDs light beams to a total beam , The secondary lens is designed as a Fresnel lens and focuses the light of the individual primary lenses on the approximately one meter away focusing point. The housing lens 74 consists of a lens base body for maintaining a minimum material thickness and disposed thereon, concentric with the center running steps, which are closer to each other in the outer region and are further away in the inner region, so have broader stages, because the overall height of the hypothetical lens with the corresponding curvature is projected to focus on the desired material thickness.

In a further development, a further LED arrangement may be arranged concentrically around the rotary handle 14 on the central area 4. This LED arrangement preferably comprises only white LEDs.

The invention is by nature not limited to the use of four satellite lights, but also includes solutions with more or less satellites.

LIST OF REFERENCE NUMBERS

2 luminaire housing 4 Central area 6 first arm 8th second arm 10 third arm 12 fourth arm 14 rotary handle 16 locking sleeve 18 spindle 20 Verstellkreuz 22 lower section 24 holding arm 26 Through opening 28 clevis 30 pivot bar 32 swivel plate 34 LED array 36 ball joint 38 retaining element 40 bearings 42 swivel axis 50 collimator lens 52 green LED 54 red LED 56 white LED 58 lateral surface 60 Light entry surface 62 recess 64 Light-emitting surface 66 center 68 holder 70 connector 72 housing cover 74 housing lens

Claims (15)

1. An operating room light with a light casing (2) comprising a light base body (page 2, para 2) forming a central region (4) (page 7, para 2), and several arms (6, 8, 10, 12) protruding from said central region and including LED illumination modules, and a focusing unit for focusing said illumination modules, characterized in that said arms (6, 8, 10, 12) together with said central region form the rigidly connected light casing (2), that the illumination modules comprise pivot plates (32) with a LED arrangement (34) disposed thereon which are fixed pivotably to said arms (6, 8, 10, 12), and that the focusing unit includes a displacement element which is displaceable in respect of height by way of a rotary handle (14) and to which there is pivotably mounted at least one pivot bar (30) mounted pivotably in a rocker point for displacement of the pivot plates (30).
2. An operating room light as set forth in claim 1, characterized in that the pivot plates (32) are mounted on pivot shafts (42).
3. An operating room light as set forth in claim 2, characterized in that the pivot shafts (42) extend transversely to an axis extending through the center point of the operating room light.
4. An operating room light as set forth in claim 3, characterized in that the pivot shafts (42) include a right angle with the axis passing through the center point of the operating room light.
5. An operating room light as set forth in claim 1, characterized in that provided at the rocking point is a mounting block which permits the simultaneous execution of a translatory and a rotational movement.
6. An operating room light as set forth in claim 5, characterized in that the mounting block includes a ball joint (36) rotatably accommodated in a holding element (38).
7. An operating room light as set forth in claim 1, characterized in that the displacement element is in the form of a displacement cross member (20).
8. An operating room light as set forth in one of the preceding claims having a collimator lens, which has the geometry of a circular truncated cone which has a peripherally extending peripheral surface (58), a light entry surface (60) which is downward in the position of installation and has a recess (62) and a light exit surface (64) which is upward in the position of installation, characterized in that the radius of curvature of the outer peripheral surface (58), the height of the collimator lens (50), the light entry surface (60), the size and geometrical configuration of the light exit surface (64) and the surface of the light exit surface (64) are matched to each other to avoid blue light in the edge region of the lens by mixing into a central region.
9. An operating room light as set forth in claim 8, characterized in that the collimator lens is adapted to achieve a light distribution curve which has a halve-value angle in the range of between ± 2 and ± 2.5 degrees, preferably ± 2 degrees, and the tenth-value angle has a range of between ± 4.0 and ± 5.0 degrees, preferably ± 4.0 degrees.
10. An operating room light as set forth in one of the preceding claims having a plurality of LEDs arranged in a group for producing a LED arrangement (34), characterized in that there are provided at least two different configurations of LED arrangements (34) which have different arrangements of colored LEDs.
11. An operating room light as set forth in claim 10, characterized in that the first configuration of the LED arrangement has the colored LEDs more in the outer region and a second configuration has the colored LEDs more in the central region.
12. An operating room light as set forth in claim 10 or claim 11, characterized in that the colored LEDs include red and green LEDs.
13. An operating room light as set forth in claims 10 through 12, characterized in that the differently colored LEDs are differently supplied with current.
14. An operating room light as set forth in claim 13, characterized in that a circuit of red LEDs is supplied with between about 40 and 50% of the current of white and green LEDs.
15. An operating room light as set forth in one of the preceding claims, characterized in that the same is adapted to comply with the low voltage directive.

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