US 5,188,028 A · Printing machine damage control system, and damage control method

Abstract

To permit triggering a torn web capturing roller system (9, 10, 11) or a web deflection unit (28) for rapid capture of a torn or damaged web (7) in a printing machine system having a printing station (2) and thus prevent wrap-around of torn webs about elements of the printing station, the web is guided about a cooling roller or cylinder (14) downstream of a web dryer and strain between and cooling roller and the side wall of the printing machine is measured. This strain is measured for example, by a piezoelectric tranducer or a strain gauge (23) coupled to a bearing (21) in a side wall (19) in the printing machine. The signal from the transducer (18), for example the strain gauge (23), is evaluated in a computer and control unit (26), for example with respect to a reference. The reference can be modified, if desired, by entering in the computer or control unit data representative of acceleration and deceleration of the machine, per square weight of the web, weight of the cooling roller or cylinder (14) and the like.

Claims20

Dependent claims

Printing machine damage control system for a web-type printing machine,

wherein said printing machine includes, sequentially in the running direction of the web, a printing station (2), a dryer unit (12) and a cooling unit (13), and said cooling unit has a cooling roller or cylinder (14), the web being at least partly looped about the cooling roller or cylinder, and
means (9, 10, 11;
28) located upstream of the printing station for separating a torn web from the printing station (2),
said system comprising, in accordance with the invention,
web tension sensing means (18, 23) operatively coupled to the cooling roller or cylinder (14) of the cooling unit (13) and generating a web tension signal representative of the tension of the web as it passes around the cooling roller;
control means (26) responsive to the web tension signal and determining whether the web tension signal is below a predetermined web tension level and hence indicative of a web tear, or damage, or incipient web tear;
and
connection means (27, 29) connected to and controlled by said control means to control said torn web separating means to separate the web from said printing station (2) upon determination by said control means that the web tension signal is below said predetermined level.

5 more elements

Dependencies are inferred from the claim text.

Printing machine damage control system, and damage control method

Life of this patent

Printing machine damage control system, and damage control method

Life of this patent

Abstract

Claims20