In one example, a device for unwinding or winding multiple rolls of print substrate includes multiple spindles each to hold a roll of print substrate and a differential operatively connected to one end of each spindle. The spindles are aligned with one another lengthwise along a spindle axis and the differential is to output torque along a differential axis offset from the spindle axis to turn the spindles on the first axis.

In one example, a device for unwinding or winding multiple rolls of print substrate includes multiple spindles each to hold a roll of print substrate and a differential operatively connected to one end of each spindle. The spindles are aligned with one another lengthwise along a spindle axis and the differential is to output torque along a differential axis offset from the spindle axis to turn the spindles on the first axis.

In one example, a device for unwinding or winding multiple rolls of print substrate includes multiple spindles each to hold a roll of print substrate and a differential operatively connected to one end of each spindle. The spindles are aligned with one another lengthwise along a spindle axis and the differential is to output torque along a differential axis offset from the spindle axis to turn the spindles on the first axis.

In one example, a device for unwinding or winding multiple rolls of print substrate includes multiple spindles each to hold a roll of print substrate and a differential operatively connected to one end of each spindle. The spindles are aligned with one another lengthwise along a spindle axis and the differential is to output torque along a differential axis offset from the spindle axis to turn the spindles on the first axis.

Individual fibers of a material layer are pinched within adjacent coils of a spring in the present invention by a spring-like surface carried by a moving object such as a conveyor belt, rotating drum or rotating puck. The spring coils are slightly opened to accept the individual fibers. Next the spring coils are closed to carry and transport the web of fibers. At a deposition point, the coil springs, carried by a moving object such as a conveyor belt, rotating drum or rotating puck, are opened slightly, releasing fibers and depositing the web at a desired location.

A web processing apparatus comprising a web transport station and a web processing station. The web transport station comprises a web tension control assembly, which comprises a first tensioning device and a second tensioning device. Said first tensioning device is movably arranged for controlling tension of a first web. Said second tensioning device is movably arranged for controlling tension of a second web independently of the tension of the first web. Said first tensioning device comprises a first interior space and the first tensioning device is arranged with respect to the second tensioning device such that the first interior space at least partly accommodates the second tensioning device. The web processing apparatus allows for accurately controlling tension of the first and second webs simultaneously and independently of one another in a tandem mode, while maintaining the possibility for controlling tension of a single web in a single mode.

In the present invention a web processing apparatus is provided comprising a web transport station and a web processing station. Said web transport station is arranged to transport, in a single mode of the web processing apparatus, a first web in a process direction towards or away from the web processing station, and to transport, in a tandem mode of the web processing apparatus, the first web and a second web in the process direction towards or away from the web processing station.

The web transport station comprises a web tension control assembly, which comprises a first tensioning device and a second tensioning device. Said first tensioning device is movably arranged for controlling tension of a first web. Said second tensioning device is movably arranged for controlling tension of a second web independently of the tension of the first web. Said first tensioning device comprises a first interior space and the first tensioning device is arranged with respect to the second tensioning device such that the first interior space at least partly accommodates the second tensioning device.