Image transfer apparatus

In an apparatus for transferring image information, including a first medium and a separate second medium, each for carrying image information and from one of which image information can be transferred to the other,

• respective drive systems for advancing said media each at a constant or substantially constant speed, and
• means for pressing one of said media into frictional contact with the other and holding the media in such contact during a time interval suited for transfer of image information from one advancing medium to the other, and for separating the media after each said interval, so that during each said interval said first medium will be advanced at exactly the speed of said second medium under the frictional force of such contact,
• means for generating a reference signal at a value representing a required speed of said media,
• said drive system of said first medium including:
• measuring circuit means for generating a measuring signal at a value which is a measure of the speed of said first medium,
• speed control means operative while said media are being advanced separate from one another for controlling the speed of said first medium to a value governed by relative values of said reference and measuring signals,
• means rendering said speed control means inactive during each interval of said media being advanced in frictional contact with one another,
• and adjusting means operable within a time interval of said media being advanced at the same speed by frictional contact with one another to produce an adjusting signal whereby, when said media are advanced separate from one another, the relation of said measuring signal to said reference signal is adjusted so as to keep the measuring and reference signals substantially equal to one another.

In an apparatus for transferring image information, including a first medium and a separate second medium, each for carrying image information and from one of which image information can be transferred to the other,

• respective drive systems for advancing said media each at a constant or substantially constant speed, and
• means for pressing one of said media into frictional contact with the other and holding the media in such contact during a time interval suited for transfer of image information from one advancing medium to the other, and for separating the media after each said interval, so that during each said interval said first medium will be advanced at exactly the speed of said second medium under the frictional force of such contact,
• means for generating a reference signal at a value representing a required speed of said media,
• said drive system of said first medium including:
• measuring circuit means for generating a measuring signal at a value which is a measure of the speed of said first medium,
• speed control means operative while said media are being advanced separate from one another for controlling the speed of said first medium to a value governed by relative values of said reference and measuring signals,
• means rendering said speed control means inactive during each interval of said media being advanced in frictional contact with one another,
• means operable within a said time interval of said media being advanced in frictional contact with one another to produce and retain an adjusting signal representing the relation of the speed of said media to said reference signal,
• and means operable thereafter when said media are being advanced separate from one another to produce an adjusted measuring signal representing the relation of said measuring signal to said adjusting signal so that the controlled speed of said first medium when it is being advanced separate from said second medium will be substantially the same as its speed when it is being advanced in contact with said second medium.