Device for measuring thickness of sheet article with magnet and probe carriers provided with rollers

An arrangement for measuring a thickness of an X-ray sheet film in an X-ray cassette loading and unloading device, the arrangement comprising a magnet carrier arranged at one side of the sheet article transportation path and spring-biased in a direction perpendicularly to the transportation path so as to be displaceable in said direction;

• a permanent magnet fixedly mounted on said magnet carrier near said first side of said magnet transportation path;
• at least one roller body arranged on said magnet carrier rotatably in a transportation direction of the sheet article and so as to be displaceable in said direction together with said magnet carrier;
• a probe carrier fixedly arranged parallel to a second side of the transportation path opposite to said magnet carrier;
• a Hall probe arranged on said probe carrier opposite to said permanent magnet at another side of the transportation path so that said magnet is displaceable perpendicularly to the transportation path and relative to said Hall probe, depending on a thickness of a transported sheet article;
• at least one roller body arranged on said probe carrier, said probe carrier having a number of said roller bodies which corresponds to a number of said roller bodies on a said magnet carrier, said roller bodies of said magnet carrier and said probe carrier being roller-shaped and rolling over one another in the transportation direction and in a plane of the transportation path which extends through the arrangement in one plane, said roller bodies of said magnet carrier including two roller bodies and said roller bodies of said probe carrier also including two roller bodies so as to form two paris of said roller bodies and control means for evaluating an output signal of said Hall probe so as to determine whether a single sheet film or a double sheet film is transported and to control the transportation correspondingly.

An arrangement for loading and unloading X-ray sheet film cassettes, comprising means for transporting an X-ray sheet film to and from a cassette along a transportation path;

• and means for preventing a double sheet film transportation, said preventing means including a magnet carrier arranged at one side of the sheet article transportation path and spring-biased in a direction perpendicularly to the transportation path so as to be displaceable in said direction, a permanent magnet fixedly mounted on said magnet carrier near said first side of said magnet transportation path, at least one roller body arranged on said magnet carrier rotatably in a transportation direction of the sheet article and so as to be displaceable in said direction together with said magnet carrier, a probe carrier fixedly arranged parallel to a second side of the transportation path opposite to said magnet carrier, a Hall probe arranged on said probe carrier opposite to said permanent magnet at another side of the transportation path so that said magnet is displaceable perpendicularly to the transportation path and relative to said Hall probe, depending on a thickness of a transported sheet article, at least one roller body arranged on said probe carrier, said probe carrier having a number of said roller bodies which corresponds to a number of said roller bodies on said magnet carrier, said roller bodies of said magnet carrier and said probe carrier being roller-shaped and rolling over one another in the transportation direction and in a plane of the transportation path which extends through the arrangement in one plane, and control means for evaluating an output signal of said Hall probe so as to determine whether a single sheet film or a double sheet film is transported by said transporting means and to control said transporting means correspondingly in accordance with said determination.