Patent Publication Number: US-2005127276-A1

Title: Sensorblock

Description:
The placement in a housing of several synthetic resin boards on which sensors are placed in order to provide a very wide optical sensor is known. It is customary to push the boards into guide grooves of an aluminum profile and to set the distance between boards in such manner by means of a spacing device so that the sensors on the boards and the sensor at the edges of the boards are at approximately the same distance from each other. In this embodiment it is however difficult to set the position of the board in the housing exactly and to correct the position of the boards relative to each other after the introduction of several boards.  
      It is the object of the invention to create an easily operated system for the production of the extra long optical sensors.  
      According to the invention this is achieved by screwing and aligning the individual boards with the light-sensitive silicon elements which essentially constitute the long sensor on at least one common support.  
      The boards are aligned on the support, e.g. an aluminum profile, in such manner that the photosensitive elements within a board and between two boards are at approximately the same distance from each other and are aligned approximately in one line.  
      Following their alignment, the boards are fixed in place, e.g. by screwing or gluing. The boards on the strip can then easily be tested electrically and optically before they are screwed to the supporting holder for the lens system and, if applicable, for illumination.  
      The support with the boards is then placed into an overall housing or is added to a housing. 
    
    
       FIG. 1  shows a cross-section through a sensor housing. The batch of material to be examined slides along the glass pane  1 . An LED illumination cell  3  mounted on a holder  4  in the housing illuminates the batch through a lens  5  and the glass  1 . The reflected light is projected through a lens  2  upon the photosensitive elements  6 . These elements are installed on a board  7 . The board is fixed by means of screws  8  in a support  9 . The support is part of the housing.