DE202011000608U1 - Mounting profile for a light curtain housing and light grid - Google Patents

Abstract

Light grid with at least one light transmitter and / or at least one light receiver, at least one control unit for the light emitter and / or light receiver, and at least one evaluation unit (9) for signals received by the light receiver, the light grille (13) having a first sub-housing (1) comprising at least the light emitter and / or the light receiver and having a second part housing (2) mechanically detachably connected thereto, which contains at least the evaluation unit (9) and / or the control unit, characterized in that the first sub housing (1) and the second sub-housing (2) is connected to at least one short-side end with a common end cap (3).

Description

Opto-electronic sensors, such as light barriers, light sensors, light curtains and light grids are usually designed and developed for use and operation on machine tools, assembly lines or other applications.

Such optoelectronic sensors are used, for example, for automation tasks. Furthermore, optoelectronic sensors, for example light barriers, light grids or light curtains, are used as safety sensors in order to protect persons, for example from machine tools or automated production lines, from dangerous movements by moving machine parts or robots. If a person enters a protected area or a protective field of such a safety sensor, such interventions are detected by a light beam interruption and then outputs of the safety sensor are switched in order to stop a movement of a machine.

Known opto-electronic sensor arrangements, such as light barriers, light scanners, light curtains and light grids have a housing in which at least one light emitter and / or a light receiver is arranged, wherein the housing has in a side wall at least one windscreen, which for the emitted light from the light emitter or the light detected by the light receiver is transparent. In this case, the term "light" refers not only to visible light, but electromagnetic waves of different frequencies, which are suitable for the construction of an optoelectronic sensor device. Depending on the configuration of the optoelectronic sensor arrangement, either only one or more light transmitters or only one or more light receivers may be located in the housing, for example in the case of one-way light barriers or one-way light gratings. However, it is also possible to arrange in a housing of the optoelectronic sensor arrangement both at least one light transmitter and at least one light receiver, which are each activated in pairs with an opposite light emitter / light receiver or are arranged as a light sensor or reflection light barrier.

Lichtgittergehäuse for light grids are almost exclusively produced in one piece as an extruded profile, which are provided for example with end caps and a windscreen.

If such a light grid according to the prior art is defective, usually the complete light grid must be replaced. This is because the light curtain housing must be opened to replace corresponding subcomponents. As a result, further components can either be damaged or in particular the optical components can be misaligned. Elaborate here are precautions to avoid electrostatic discharges against sensitive electronic components. Especially in the field of safety technology, the opening of a sensor by non-manufacturer personnel is problematic, since thereby the proper sensor function can not be guaranteed.

A previously unpublished application of the applicant with the application number 09 009 016.8 relates to a light grid with an optical housing and a gondola housing which is docked to the optical housing. The nacelle housing has an evaluation unit and is smaller than the optical housing formed.

Although the nacelle housing can be replaced independently of the optical housing in the event of a defect, but for the connection of the nacelle housing to the optical housing alongside an opening must be provided, which is expensive to manufacture.

From the DE 20 2007 010 493 U1 a housing for a light grid is known, comprising at least one light emitter and / or a light receiver, which is formed as a substantially cylindrical hollow profile with a front side, a bottom side, a first side wall and a second side wall and composed of exactly one first element and one second element is, wherein the first element comprises at least the first side wall and the second element comprises at least the second side wall.

From the DE 10 2007 014 170 A1 a light grid is known, wherein the housing of the light grid is arranged on a frame profile. The housing is attached via at least one fastener on or in the frame profile. Furthermore, at least one first contact element for producing an electrical contact between the housing and the frame profile is provided. On the frame profile itself, a second contact element is provided for electrical contacting. For this purpose, the frame profile can be dimensioned such that conventional connectors for producing the electrical contact can be arranged on it.

The object of the invention is to provide a mounting and maintenance-friendly light grid, which may have an outer contour of conventional light grid housing. Another task is to easily define the functional scope of a light grid during production and / or after production.

The object is achieved with a light grid having at least one light transmitter and / or at least one light receiver, at least one control unit for the light emitter and / or light receiver and at least one evaluation unit for signals received by the light receiver, wherein the light grating has a first sub-housing which at least the Includes light transmitter and / or the light receiver and having a releasably mechanically connected thereto second sub-housing containing at least the evaluation unit and / or control unit, wherein the first sub-housing and the second sub-housing are connected at least one short-side end with an end cap.

By the first sub-housing and the second sub-housing, the light grid is modular, whereby both sub-housing can be replaced independently. In particular, only at least a single end cap to remove the respective sub-housing to remove and insert a new sub-housing. The new inserted sub-housing can be provided with protective caps until replacement in order to protect the interior of the light grid.

Due to the two sub-housings, the final profile housing of the assembled profile is formed from the two sub-housings. The final profile housing can have the profile shape of a conventional one-piece profile housing.

The first sub-housing contains in addition to the light emitters and / or light receivers also corresponding associated optics and alongside a windscreen for the light input and / or light output. The windscreen is tightly connected to the first part housing. The first part housing thereby forms an optically active module. The first sub-housing has for receiving the light emitter and / or light receiver and / or the optics small tolerances to ensure accurate alignment of the components.

The second sub-housing has no light emitter and / or light receiver, which are provided for an object detection. The second sub-housing is provided only for other electronic components such as the evaluation unit. Therefore, the second sub-housing has greater tolerances than the first sub-housing and is therefore cheaper to produce than the first sub-housing.

Since the second sub-housing comprises the further electronic components and the evaluation unit and / or control unit, by selecting the second sub-housing, for example, the functional scope of the light grid can be determined. By combining a first sub-housing with different second sub-housings, which have a different range of functions, so certain light grid functions can be provided. As a result, a modular range of functions of the light grid can be realized. The functions of the light grid can be determined in the final assembly or directly on site by selecting the second sub-housing. The first partial housing substantially determines the optical resolution of the light grid.

Advantageously, the sub-housings have an identical length. As a result, the connection surface for the end caps of both sub-housings in one plane is possible. This allows the end cap to be made easier. For example, the surface for a seal for both sub-housings is in a common plane, whereby the housing can be sealed more easily by the end caps.

In a further development of the invention, a light entry side and / or light exit side of the first sub-housing is provided on one of the side surfaces, which does not face the second sub-housing in the mounted state. The light entrance side and / or light exit side is closed with the front screen. The windscreen is provided on one of the side surfaces. As a result, different variants of the light grid can be provided, which provide an optimal side for the light entry or light exit for different mounting options.

In a further development of the invention, the first sub-housing and the second sub-housing are rotated by 180 ° to each other mountable. In the case of the first sub-housing, which has the front screen on a side wall which connects to the side wall which is connected to the second sub-housing, the light entrance or the light exit can be rotated by 180 °, so that this on the opposite side of the light grid housing lies. As a result, the light grid can be adapted to mechanical conditions before final assembly.

In a development of the invention, the first sub-housing has at least one additional evaluation unit and / or control unit for the at least one light transmitter and / or light receiver. Due to the additional control unit, in the case of several light transmitters, these can already be activated in a specific sequence. Also, the first sub-housing may have an evaluation unit for a pre-evaluation of the received signals.

In a preferred embodiment, the sub-housings are electrically connected at least one short-side end via the end cap. The electrical connections of the end caps are when placing the end caps each with the Contacts of the sub-housing connected. It may be commercially available connectors. Preferably, the electrical connections are arranged symmetrically and / or double, so that an orientation to the sub-housings plays no role. The end caps can be arranged rotated by 180 ° and even in case of rotation of the first part housing by 180 °, the identical end cap can be used. This also makes it possible to use only one type of end cap connection for both sides.

In a further development of the invention, at least one end cap has an electrical connection for electrical connection to the outside. As a result, the light grid can be connected to an external control and evaluation unit or directly to a programmable logic controller or, for example, directly with a machine control in order to influence and possibly stop a dangerous movement or dangerous condition of a machine, if an unauthorized object in the protective field is detected. The electrical connection makes it possible to transmit control and diagnostic information.

Preferably, the electrical connection is formed to the outside by a connector, a connector, a cable or a cable tail. A connection socket or a connection plug have the advantage that different connecting cables can be connected to the light grid. A cable or cable tail has the advantage that it requires little space and can be used even with very small light curtain housings.

In a further development of the invention, the first sub-housing or the second sub-housing has a longitudinal groove and the second sub-housing or the first sub-housing has a corresponding longitudinal projection or latching projection to the groove of the other sub-housing to connect the first and second sub-housing together. Through the groove, the two sub-housings can be stably connected together. Through the groove, the two sub-housings are locked in at least one direction or fixed to each other. The sub-housing are then z. B. by screws or snaps or the end caps firmly connected.

In a further development of the invention, the first sub-housing and the second sub-housing by means of a dovetail groove and the corresponding dovetail are designed to be displaceable. As a result, the sub-housings are locked in at least two mutually orthogonal spatial directions. In the third orthogonal spatial direction, the sub-housings can be moved against each other to assemble or disassemble them. For final fixation now only the end caps must be mounted on both sides. Instead of the dovetail may also be provided a C-shaped groove or a T-shaped groove and a C-shaped projection or a T-shaped projection.

At least one partial housing preferably has a mounting bracket. This mounting bracket can be designed as a C-groove, a T-slot or, for example, as a dovetail groove. With this mounting bracket, the light grid can be mounted on a machine or a designated mounting frame. If the mounting bracket is provided only on the second sub-housing, the first sub-housing can be replaced without removing the first sub-housing from the mounting bracket. This of course also applies to the opposite case, when the mounting bracket is arranged only on the first part of the housing.

Preferably, the mounting bracket is formed by two sub-housings together. This leads to a higher stability, since both partial housings are fastened by the jointly formed mounting bracket. As a result, slipping of the two sub-housing is difficult.

In a further development of the invention, the mounting bracket is identical in cross-section to the mechanical connection between the first and second part of the housing. For example, the dovetail support between the first and second sub-housings is identical to the dovetail support as a mounting support.

However, it can also be provided that the first part housing and the second part housing are mounted spatially separated from each other. Then the part housings are each closed with their own end caps.

1 shows a light grid according to the prior art;

2 shows a light grid with a first and second sub-housing according to the present invention;

3 shows a light grid according to the invention with an electrical connection;

3a and 3b show light curtains according to the invention with end caps;

4 and 5 each show a light grid according to the invention with a respective lateral front screen;

1 shows a perspective view of a light grid 12 According to the state of the art. This has a housing which consists essentially of an elongated hollow profile, in the interior of optics 4 and electronic components such as at least one light emitter and / or at least one light receiver, in the present example a plurality of light emitters are arranged. The housing therefore has on one side a for the light emitted by the light emitters or the light receivers to receive light transmitted front screen 10 through which the light can escape from the housing or enter the housing. The housing is at its respective short-side ends with end caps 3 locked.

2 shows a two-part light grid housing 13 according to the present invention, consisting of a first part housing 1 and a second sub-housing 2 , The outer contour of the light grid according to the invention 13 corresponds to the light grid 12 according to 1 , This is the mechanical interface of the light grid 12 and 13 according to 1 and 2 identical. The first part housing 1 contains the optics 4 and a plurality of light emitters and / or light receivers. The number of light transmitters and / or light receivers may be, for example, the number of 1 to about 240. Other numbers of light emitters and / or light receivers are conceivable. The light emitter and / or light receiver are accommodated on a printed circuit board. The second part housing 2 contains an evaluation unit 9 to evaluate the signals of the light receivers and to form logic signals and output signals. Next is in the second part housing 2 a control unit provided to the light emitter in the first part housing 1 head for. However, it can also be provided that an additional evaluation unit and / or control unit is provided in the first sub-housing in order to carry out a preliminary evaluation of the received signals or to carry out a pre-control of the light emitter.

The first part housing 1 consists of an extruded profile, which has an opening for a windshield 10 having. The light emitter and / or light receiver are in the sub-housing behind the windscreen 10 arranged so that the light of the light emitter and / or the light for the light receiver through the windscreen 10 can occur. The light may be visible or invisible light. Preferably, light in the infrared range is used.

The first part housing 1 consists of the side wall with the opening for the windscreen of three other side walls, which are interconnected. The first part housing 1 is produced in one piece by extrusion. The side walls attached to the side panel with the windscreen 10 connect, are provided with a projection, with a further projection of a second sub-housing a mounting bracket 8th forms.

The mounting bracket 8th has, for example, the shape of a dovetail. The mounting bracket 8th is in this embodiment together by a respective side wall of the first part housing 1 and the second sub-housing 2 educated. But the mounting bracket can also only on one or more sides of one or both sub-housing 1 . 2 be arranged.

The second part housing 2 is substantially symmetrical to the first sub-housing except for one connection side 1 educated. The two sub-housings 1 . 2 are about a lead 7 connected together in length. The lead 7 of the first part housing 1 engages in a groove 11 of the second sub-housing 2 one. This allows the two sub-housings 1 . 2 simply be pushed together lengthwise for assembly. In the embodiment shown according to 2 has the lead 7 the shape of a swallowtail. However, other forms of protrusions may be used 7 be provided. By the projection 7 and the groove 11 are the part housings 1 . 2 fixed in two orthogonal directions to each other. About the third orthogonal direction to the sub-housing 1 . 2 moved and separated or put together.

The connection between the part housings 1 . 2 can also be solved via another mounting option. For example, a lead 7 and a corresponding groove may be provided, which can be plugged directly into each other, for example. The projection is preferred 7 and the groove 11 each part of the respective sub-housing 1 . 2 and designed so that they can be produced by the extrusion process.

An electrical connection of the sub-housing 1 . 2 is about the end caps 3 produced. To have the sub-housing 1 . 2 on at least one end face electrical connections, such as male or pin headers, by placing the respective end cap 3 be contacted. In this way, the sub-housing 1 . 2 electrically contacted or connected without costly openings in the sub-housing longitudinal sides for connections between the sub-housings 1 . 2 would be necessary. About the end caps 3 become the part housings 1 . 2 Also sealed, so no dirt or moisture in the sub-housing 1 . 2 can get.

Preferably, these end-side connections are designed in such a double that an orientation of the sub-housing 1 . 2 , or the end cap 3 does not matter. Ie. the end cap 3 can also be rotated 180 ° on the sub-housing 1 . 2 to be assembled. But it can also be like that 4 and 5 executed, one of the sub-housing 1 . 2 turned lengthwise by 180 ° to the other part housing 1 2 to be assembled.

3 shows the light grid according to the invention 13 in a side view. The light grid 13 shows the first part housing 1 and the second sub-housing 2 in a mounted state. The connected part housings 1 . 2 are each at the ends with end caps 3 connected. One of the end caps 3 has an electrical connection with a plug in order to provide the light grid with energy and to forward or receive switching and possibly information signals. As in the example shown, the connection may be a cable tail or a plug or socket directly in the end cap 3 integrated.

3a shows a light grid 13 , according to 3 in which the second part housing 2 shorter at one end than the first part housing 1 , The end cap 3 without the electrical connector is angularly formed to compensate for the length of the shorter second sub-profile 2 ,

3b shows a light grid 13 according to 3 in which the second part housing 2 shorter at both ends than the first part housing 1 , Both end caps 3 are angularly formed to compensate for the length of the shorter second part of the housing 2 , It is of course also provided, the first part housing 1 shorter than the second part housing 2 train.

4 and 5 each show a light grid according to the invention in a preferred embodiment 13 with a respective lateral windscreen 10 for the entrance of light or light. The windscreen 10 is located on one side of the light grid 13 passing through the two sub-housings 1 . 2 formed together. By turning the first part housing 1 according to 4 180 ° can now be the side with the windscreen 10 turn 180 ° so that the windscreen 10 , as in 5 shown on the opposite side of the light grid 13 located.

On the side of the first part housing 1 the mounting side to the other sub-housing 2 opposite, controls and display elements can be provided in addition, which are easily accessible on this page for an operator. These controls can then be operated for an operator without interrupting the protective field.

For storage of the housing part 1 . 2 can the end faces of the sub-housing 1 . 2 Protected against damage or contamination with simple, inexpensive protective caps.

The two sub-housings 1 . 2 do not necessarily have to be arranged next to each other for operation. For example, it would also be possible for each sub-housing 1 . 2 a separate Teilendkappe provided with a line to a common end cap 3 are connected, so that the first part of the housing may be arranged spatially separated from the second part of the housing.

LIST OF REFERENCE NUMBERS

1

first part housing

2

second sub-housing

3

endcap

4

optics

5

circuit board

7

head Start

8th

mounting bracket

9

evaluation

10

windscreen

11

groove

12, 13

light Curtain

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 202007010493 U1 [0008]
• DE 102007014170 A1 [0009]

Claims (13)

Light grid with at least one light transmitter and / or at least one light receiver, at least one control unit for the light emitter and / or light receiver, and at least one evaluation unit ( 9 ) for signals received by the light receiver, wherein the light grid ( 13 ) a first sub-housing ( 1 ), which includes at least the light emitter and / or the light receiver and a releasably mechanically connected thereto second partial housing ( 2 ), which at least the evaluation unit ( 9 ) and / or the control unit, characterized in that the first part housing ( 1 ) and the second sub-housing ( 2 ) at at least one short-side end with a common end cap ( 3 ) are connected. Light grid according to claim 1, characterized in that the partial housings ( 1 . 2 ) have an identical length. Light grid according to one of the preceding claims, characterized in that a light entry side and / or light exit side of the first part housing ( 1 ) is provided on one of the side surfaces, not the second sub-housing ( 2 ) facing in the assembled state. Light grid according to one of the preceding claims, characterized in that the first partial housing ( 1 ) and the second sub-housing ( 2 ) are rotated by 180 ° to each other mountable. Light grid according to one of the preceding claims, characterized in that the first partial housing ( 1 ) includes at least one additional evaluation and / or control unit for the at least one light emitter and / or light receiver. Light grid according to one of the preceding claims, characterized in that the partial housings ( 1 . 2 ) electrically at least one short-side end over the end cap ( 3 ) are connected. Light grid according to one of the preceding claims, characterized in that at least one end cap ( 3 ) has an electrical connection for electrical connection to the outside. Light grid according to claim 7, characterized in that the electrical connection is realized to the outside by a connector, a connector socket, a cable or a cable tail. Light grid according to one of the preceding claims, characterized in that the first partial housing ( 1 ) or the second sub-housing ( 2 ) has a longitudinal groove and the second sub-housing ( 2 ) or the first part housing ( 1 ) has a corresponding longitudinal projection to the groove of the other sub-housing to connect the first and second sub-housing together. Light grid according to claim 9, characterized in that the first partial housing ( 1 ) and the second sub-housing ( 2 ) are formed by means of a dovetail groove and the corresponding dovetail to each other displaced. Light grid according to one of the preceding claims, characterized in that at least one partial housing ( 1 . 2 ) a mounting bracket ( 8th ) having. Light grid according to one of the preceding claims, characterized in that the mounting bracket ( 8th ) of both sub-housings ( 1 . 2 ) is formed. Light grid according to claim 11, characterized in that the mounting bracket ( 8th ) in cross-section is identical to the mechanical connection of the sub-housing ( 1 . 2 ).

Images