Patent Application
20180202714
The invention relates to modular LED emitter units including at least two LED emitter modules and with one connector for the supply of electrical power to the LED emitter modules, and methods of using the same.
Certain conventional LED emitter units are self-contained units having their own electrical connector and connecting means for establishment of a force-locked or form-fitting connection to a mounting frame. Depending on the design and number of integrated LED lamps, one or more cables are needed to establish the data and electrical power connection.
The LED emitter unit for UV curing of printing inks known from EP 2 851 637 A1 has multiple LED emitter modules each equipped with a multitude of LEDs for the emission of UV light arranged adjacent to each other and grouped into multiple LED zones. Each LED zone can be switched on and off independent of the others and can be controlled with regard to the UV power, intensity, wavelength or emission time of the LED emitter modules combined in them.
However, it would be desirable to provide improved LED emitter units, and methods of using the same, overcoming one or more of the deficiencies of conventional LED emitter units.
According to an exemplary embodiment of the invention, an LED emitter unit is provided. The LED emitter unit includes at least two LED emitter modules and one connector for supply of electrical power to the LED emitter modules. Each of the LED emitter modules includes at least one LED for emission of UV radiation of a wavelength below 430 nm or of IR radiation of a wavelength above 780 nm. Each LED emitter module includes a housing equipped with a radiation exit window and is configured as an insertion assembly for a docking station. The docking station includes at least one connecting means for establishing a form-fitting mechanical connection to the housing and one plug element of an electrical plug connection. The housing includes a rear side including a mechanical counterpart that corresponds to the connecting means and a counter element that corresponds to the plug element of the electrical plug connection. The connecting means of the docking station and the corresponding mechanical counterpart of the rear side of the housing are arranged such that establishing the form-fitting mechanical connection is associated with establishing an electrical connection between the plug element and the counter element.
According to another exemplary embodiment of the invention, methods of using the LED emitter units described above are provided. For example, such LED emitter units may be used for curing at least one of an ink or a coating in a printing machine.
The invention is best understood from the following detailed description when read in connection with the accompanying drawings. It is emphasized that, according to common practice, the various features of the drawings are not to scale. On the contrary, the dimensions of the various features are arbitrarily expanded or reduced for clarity. Included in the drawings are the following figures:
In connection with multi-beam LED emitter units, the number of the electrical and mechanical connections tends to increases with the number of lamps included in the multi-beam LED emitter unit. The assembly and disassembly of the lamps for cleaning, maintenance or replacement purposes is associated with a major cabling effort and time expenditure. Connection errors or loose contacts may occur easily.
Emitter units with fixed lamps are usually replaced completely even if only individual components are defective. This is often the case, because replacing defective components is time-consuming such that it is common to insert a new complete emitter unit to avoid extensive downtimes.
Aspects of the invention are therefore based on the object to provide an LED emitter unit that is easy to maintain and mount, and that reduces or eliminates the above-mentioned cabling effort, and makes optimal use of the available installation space.
According to exemplary aspects of the invention, each LED emitter module includes a housing equipped with a radiation exit window and is designed as an insertion assembly for a docking station. The docking station includes at least one connecting means for establishing a form-fitting mechanical connection to the housing and one plug element of an electrical plug connection. The housing includes a rear side of the housing that includes a mechanical counterpart that corresponds to the connecting means and a counter element that corresponds to the plug element of the electrical plug connection. The connecting means of the docking station and the corresponding mechanical counter-part of the rear side of the housing are arranged appropriately such that establishing the form-fitting mechanical connection is associated with establishing an electrical connection between plug element and counter element.
Exemplary embodiments of the invention relate to LED emitter units including multiple modular insertion assemblies. These assemblies shall also be referred to as “LED emitter modules” or “single modules” hereinafter. Each of the modules includes its own housing that accommodates at least one light-emitting diode (LED), but preferably a multitude of LEDs. The housings of the LED emitter modules are arranged, for example, adjacent to each other. The housing-mounted modular design of the LED emitter units according to the invention is advantageous in that any format width for irradiation can be provided based on an LED emitter module housing of a small standard size by joining multiple of the single modules.
Each LED emitter module may include multiple LEDs that can be subdivided into one or more segments. In an embodiment of the invention, not only the LED emitter modules, but the segments also, can be controlled separate of each other, in particular can be switched on and off and can have their emission power be set, for example, be dimmed. Due to said adaptability, a failed LED emitter module having a given nominal power can be replaced by a different LED emitter module having a different nominal power without having to replace the control electronics.
Exemplary docking stations are another important foundation of the modular design of the LED emitter unit (can also be called “backplane” referring to similar components in computer and electrical engineering) by means of which the distribution of the electrical supply, and preferably the data transmission to a control also, is being implemented. Exemplary docking stations include a design adapted to the specific application of the emitter unit; for example, it comprises a lateral extension that is at least as large as the format width of the substrate to be irradiated and it is provided with a number of docking sites that corresponds to the number of single modules required to cover the format width. The single modules are designed as insertion assemblies for the docking station.
In a simple embodiment, passively cooled LED emitter modules are used. The passive cooling of the emitters is effected without forced cooling and does not require any electrical components. But the modular concept is particularly well-suited for the use of liquid-cooled or air-cooled LED emitter modules. Since the supply of the gaseous or liquid coolant can be guided centrally via the docking station. Accordingly, for example, in the case of air cooling, the aspiration or discharge of the cooling air can also be effected via the docking station.
The docking station is a passive component, which essentially provides a mounting wall facing the LED emitter modules. The mounting wall is provided with connecting and connector elements for mechanical and electrical connection of the LED emitter modules. The LED emitter modules occupy slots on the inside of the docking station. The cabling may only need to be done once and is essentially done on or within the mounting wall. The internal power distribution of the emitter unit takes place, for example, via a current distribution rail along the mounting wall. The current distribution rail is firmly integrated into the design of the emitter unit and therefore necessitates no additional component. Preferably, the data distribution also takes place via a data line running along or within the mounting wall. A lateral covering cap can be provided on one side or both sides of the mounting wall.
Due to the presence of the docking station, the individual LED emitter modules may not require connecting cables for power supply and data transmission. The modular design of the emitter unit makes it feasible, at least, to strongly reduce the number of cables required. The mounting, maintenance and replacement of single modules proceed even more easily than the replacement of a complete emitter unit. Errors in the establishment of cable connections may be excluded. If an individual LED emitter module fails, it can be replaced without much effort in a short period of time. There is no need to return the entire emitter unit to the manufacturer for repair or to call in a service technician. Consequently, there are reduced maintenance costs and downtimes.
Exemplary embodiments of the emitter units according to the invention are specified in the sub-claims. In detail:
According to an exemplary embodiment of the invention, the docking station is designed to accommodate at least three insertion assemblies of identical design and includes a number of electrical plug elements and connecting means that is equivalent to the number of LED emitter modules.
According to another exemplary embodiment of the invention, the plug elements are mounted on a common rail and are electrically connected to each other. The rail, for example, a current distribution rail, may extend on the side of the mounting wall of the docking station that faces the insertion assemblies.
According to another exemplary embodiment of the invention, the rear side of the housing and the docking station are provided with mutually corresponding guiding means that engage each other in gliding manner when the LED emitter module is being inserted into the docking station to finally effect a mechanical joined connection.
The fastening variant simplifies the implementation of a mounting of the LED emitter modules without tools.
According to another exemplary embodiment of the invention, the mechanical counterpart of the rear side of the housing includes a conically tapering guiding pin.
Inserting the LED emitter module into the docking station, the at least one guiding pin reaches a corresponding receptacle provided therein. The conical tapering simplifies the insertion; whereby it is sufficient if the outward-facing tip of the guiding pin is designed to be conical.
According to another exemplary embodiment of the invention, the housing includes a rear side of the housing, adjacent side walls, a front of the housing situated opposite from the rear side of the housing as well as a top of the housing and an underside of the housing, whereby the exit opening for the emitted light is arranged on the underside of the housing.
In another advantageous exemplary embodiment, the housing is provided with ventilation slits and the docking station is provided with ventilation openings, whereby the ventilation slits and the ventilation openings are connected such as to be in fluid communication with each other.
A gaseous coolant for cooling the single modules can be aspirated or discharged through the ventilation slits and the ventilation openings. Due to the ventilation slits and ventilation openings being in fluid communication, the coolant aspirated in one case is guided to the other site and cools the single module on this ventilation duct, for example, the LEDs contained therein.
Advantageously, the ventilation slits may extend on the top of the housing in the direction of the rear side of the housing towards the front of the housing and extend beyond the top of the housing along an upper section of the front of the housing, whereby the front of the housing arches outwards.
The rear side of the housing and the adjacent side walls may be substantially level and extend perpendicular to the underside of the housing.
The top of the housing is may be arched outwards and is provided with the ventilation slits.
In an alternative exemplary embodiment, the front of the housing is designed to be essentially planar, whereby it extends perpendicular to the underside of the housing.
Another exemplary embodiment of the LED emitter unit relates to the plug element of the electrical plug connection being designed for the transmission of data and energy.
The plug connection for mechanical connection between the LED emitter module and the docking station is includes a plug element and a counter element or of multiple plug elements and counter elements. Plug elements and counter elements are appropriately arranged on the rear side of the housing and on the docking station in a mutually corresponding manner such that establishing the form-fitting mechanical connection is associated with concurrently establishing an electric connection. In this context, concurrently shall be understood to not necessarily mean simultaneously, but automatically; without further ado. Spatially separated plug connections for the electrical connection and for the data connection can be provided. Or a single plug connection can create both the electrical connection and the data connection; in this case, this would concern a multi-function element. The plug element actually provided for the electrical connection can also establish, or contribute to, the mechanical connection between the LED emitter module and the docking station.
With regard to an optimally homogeneous intensity distribution of the UV and/or IR radiation across the row of LED emitter modules of the LED emitter unit, there may be a distance of 4 mm or less provided between the radiation exit windows of neighbouring LED emitter modules.
Due to the dense positioning of the emission exit windows of the single modules along the LED emitter unit, the intensity distribution of the radiation is particularly homogeneous. The homogeneous intensity distribution is evident in that the radiation intensity, measured at a distance of 20 mm from the plane of the emission exit windows, does not deviate by more than 15% from an average value in any location.
Another exemplary embodiment of the LED emitter unit relates to the connecting means for establishing the form-fitting mechanical connection, and the plug element of the electrical plug connection, being provided at an inside of the docking station that faces the rear side of the housing of the LED emitter module and has a lateral extension that is at least as large as the format width of the substrate to be irradiated.
The irradiation intensity of the emitter unit according to certain exemplary embodiments of the invention (measured at the exit window) is in the range of 1 to 500 Watt/cm2, preferably at least 10 Watt/cm2. It may be designed for industrial applications. For example, for the curing of ink or coating in a printing machine, sintering of metallic, electrically-conductive pastes (printed conductors) or for forming processes for thermoplastic materials. However, configuring it with ultraviolet LEDs makes it well-suited also for surface treatments; activation of cross-linking processes, surface activation, surface cleaning, surface modification; air treatment; odour removal, and for medical UV applications. Alternatively, the LED emitter unit according to the invention may be configured with at least one infrared LED lamp and can be used for drying processes or other heating, heat or tempering processes. Alternatively, the LED emitter unit according to the invention may be configured with at least one infrared LED lamp and at least one ultraviolet LED lamp and can be used for applications, in which both heat and UV light are needed, such as during the drying of paints, for curing of adhesives or for artificial culturing of plants.
The emitter unit according to aspects of the invention may be used not only in continuous processes and batch processes, but also as a radiation source for use with processing units with several motion axes (e.g., robots).
A rear-side cladding 6 is evident in the view of the rear of the LED emitter unit 1 shown in
The view of the LED emitter unit 1 shown in
Cooling air for cooling the LEDs 55 (see
When the LED emitter module 2 is being inserted, lateral guide rails 10 on one side of the emitter module 2 engaged corresponding guide elements of the neighbouring unit. The neighbouring unit is either another LED emitter module 2 or the closing covering cap 4 of the docking station 7. Electrical plug connections (adapter 8) are generated automatically during the inserting process and are capable of transmitting both electrical current and data. The power supply lines of all emitter modules 2 extend to a common current distribution rail 9 that extends in a through-going hollow space of the docking station 7 from a side cap 4 to the other side cap 4. Likewise, the data communication lines of the LED emitter module are combined in a common data line that extends inside the docking station. Current distribution rail and data line leads to a central lamp supply and control unit. The electrical plug connection serves for establishing the power supply for the electronics of the LED module, for the LEDs and for any cooling mechanism, for example, a fan. The electronics incorporated into the insertion assemblies serve, for example, for controlling a fan and for recording error protocols.
The current distribution rail can be fabricated from a single part or multiple parts.
The lateral extension of the docking station 7 corresponds to the format width of the substrate to be irradiated. In the exemplary embodiment of
The LED emitter unit 50 of
Alternatively or in addition to the guide rail 10 described above based on
Each of the LED emitter modules 2 is equipped with a multitude of light emitting diodes 55 (LEDs). The light exit opening is provided on the rear side 12d of the housing of the LED modules 2, as is schematically shown in
In the present exemplary embodiment, all LEDs 55 emit light from the ultraviolet wavelength range (UV) below 430 nm.
In an alternative embodiment, at least one of the LED emitter modules 2 is equipped with LEDs that emit light from the infrared wavelength range (IR). The infrared spectral range is the wavelength range between 780 nm and 1 mm. In this case, it is preferred that all LEDs 55 of the LED emitter unit 1 are IR LEDs.
In another alternative embodiment, at least one of the LED emitter modules 2 is equipped with LEDs that emit light from the visible wavelength range. The visible spectral range is the wavelength range between 380 nm and 780 nm.
In another alternative embodiment, at least one of the LED emitter modules 2 is equipped with LEDs that emit light from the ultraviolet wavelength range and with LEDs that emit light from the infrared wavelength range.
Although the invention is illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2015 111 507.7 | Jul 2015 | DE | national |
| 10 2016 102 279.9 | Feb 2016 | DE | national |
This application is a U.S. National Phase filing of international patent application number PCT/EP2016/065777 filed Jul. 5, 2016 that claims the priority of German patent application number 102015111507.7 filed Jul. 15, 2015 and German patent application number 102016102279.9 filed Feb. 10, 2016. The disclosures of these applications are hereby incorporated by reference in their entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2016/065777 | 7/5/2016 | WO | 00 |
