Spine Nipping Press VFN 700
Reduction of the spine built up caused by folding and thread sewing
 

In the production of hardcover products, the spine build-up of the book blocks caused by folding and resulting from thread sewing is a well-known problem. This does not only lead to problems in downstream processes but can also have a negative effect on the quality of the product – such as glue penetration into the book block or uneven glue application. To counteract this problem, book producers often use simple manual or semi-automatic presses. However, this is not efficient and generates an additional step in the manufacturing process. With the 35 cycles per minute inline-capable spine nipping press VFN 700, Muller Martini has the right answer to this challenge.

Optimum book block shape

With the VFN 700, each book block is pressed in the spine area which significantly reduces the spine build up. This ensures the best possible book block shape with all common paper types and their different characteristics. The pressing force is generated by a pneumatic cylinder according to the toggle lever principle, resulting in a pressing force of up to 60 kN. The spring-loaded pretensioning clamps hold the book block in place and by that prevent the deformation of the book spine.


 

Diverse Versions

The VFN 700 has been designed for all conventional thread sewing applications and is therefore available in three versions. It can be configured for the inline production using a Ventura Connect system or a Ventura MC 160/200, including a stacker with belt delivery. This version can be configured individually. The VFN 700 can also be configured offline, i.e. as a standalone machine, and loaded manually with book blocks from various thread sewing machines.
 

Several operating modes for every case of application

Four operating modes complete the machine and make it possible to cover every case of application. If the VFN 700 is not required, it can pass through the book blocks unpressed in "bypass mode". In "automatic mode" the book blocks are pressed after an automatically calculated pressing time, while in "press & hold mode" each book block is pressed until the next one arrives. Finally the mode "pressing time: fix" allows each book block to be pressed according to a manual presetting.