Copying machine of the diazo type

A copying machine of the diazo type, said machine comprising:

• a light exposure zone for exposing to light a diazo type photosensitive sheet superposed with an original;
• a development zone for developing a light exposed photosensitive sheet;
• a delivery mechanism operatively positioned for feeding the original and diazo type photosensitive sheet to said light exposure zone and for forwarding the light exposed photosensitive sheet to said development zone;
• a transparent cylinder positioned in said light exposure zone and capable of rotating with a superposed assembly of the original and photosensitive sheet contacting the outer surface thereof;
• a heat-generating light source mounted in the interior of said transparent cylinder;
• fan means operatively mounted for feeding cold air into said transparent cylinder from a first end thereof and for cooling the outer surface of said transparent cylinder substantially uniformly along the entire length thereof;
• a temperature-detecting means thermoconductively contacted with the outer surface of said transparent cylinder to detect the temperature of said outer surface;
• a temperature controlling means coupled to said temperature-detecting means and said fan means for controlling the air feed rate of said fan means in response to signals from said temperature-detecting means, to control the temperature of the outer surface of said transparent cylinder within a predetermined temperature range;
• said temperature-detecting means including a first temperature-detecting mechanism adapted to detect a predetermined temperature which approximates the predetermined temperature range of the outer surface of said transparent cylinder and a second temperature-detecting mechanism adapted to detect a predetermined temperature which is higher than said predetermined temperature range of said transparent cylinder;
• and
• said temperature-controlling means including a change-over switch mechanism means for rotating said fan means at a fixed speed to maintain the temperature of the outer surface of said transparent cylinder when said temperature reaches the predetermined temperature of said first temperature-detecting mechanism, for rotating said fan means at a speed lower than said fixed speed to raise the temperature of the outer surface of said transparent cylinder when said temperature is lower than the predetermined temperature of said first temperature-detecting mechanism, and for rotating said fan means at a speed higher than said fixed speed to lower the temperature of the outer surface of said transparent cylinder when said temperature is higher than the predetermined temperature of said first temperature-detecting mechanism and reaches the predetermined temperature of said second temperature-detecting mechanism.

A copying machine of the diazo type to be applied to both monochromatic reproduction and multicolor reproduction, said machine comprising:

• a light exposure zone for exposing to light a superposed assembly of a diazo type photosensitive sheet and an original having thereon a layer of a heat-transferable coupler at preselected areas of the surface thereof confronting a photosensitive layer of said photosensitive sheet and for heat-transferring the coupler onto the diazo type photosensitive sheet;
• a development zone for developing a light-exposed and coupler-transferred photosensitive sheet;
• a delivery mechanism operatively positioned for feeding the original and diazo type photosensitive sheet to said light exposure zone and for forwarding the light-exposed and coupler-transferred photosensitive sheet to said development zone;
• a transparent cylinder positioned in said light exposure zone and adapted for rotating with a superposed assembly of the original and photosensitive sheet contacting the outer surface thereof;
• a heat-generating light source mounted in the interior of said transparent cylinder;
• fan means operatively positioned for feeding cold air into said transparent cylinder from a first end thereof and for cooling the outer surface of said transparent cylinder substantially uniformly along the entire length thereof;
• a temperature-detecting means thermoconductively contacted with the outer surface of said transparent cylinder to detect the temperature of said outer surface;
• a temperature controlling means coupled to said temperature detecting means and said fan means for controlling the air feed rate of said fan means in response to signals from said temperature-detecting means, to control the temperature of the outer surface of said transparent cylinder within a predetermined temperature range;
• said temperature-detecting means including a first temperature-detecting mechanism for monochromatic reproduction which causes said temperature controlling means to control the temperature of the outer surface of said transparent cylinder to within a first predetermined temperature range suitable for light exposure for monochromatic reproduction, and a second temperature-detecting mechanism for multi-color reproduction which causes said temperature controlling means to control the temperature of the outer surface of said transparent cylinder to within a second predetermined temperature range suitable for light exposure and heat transfer of the coupler for multi-color reproduction, said second predetermined temperature range being higher than said first predetermined temperature range;
• and
• a change-over switch means, having first and second contacts respectively connected to said first and second temperature-detecting mechanisms, for selectively actuating said first temperature-detecting mechanism for monochromatic reproduction and said second temperature-detecting mechanism for multi-color reproduction.