US 5,611,396 A · Method and apparatus for throttle valve control of a calender roll actuator

Abstract

A throttle valve is provided in each actuator of a calender roll controller with the throttle valve controlling an internal air orifice within each actuator to provide a substantially uniform air mass flow of either hot or cold air. Each throttle valve is controlled in response to the temperature of the air being delivered by the actuator such that a smaller orifice is provided for hot air than for cold air to provide substantially uniform air mass flow from each of the actuators and therefore substantially uniform air velocity to better control the temperatures of the longitudinal zones of a calender roll and better maintain boundaries between the zones. In addition to throttle valve control of the actuators, an air scoop concentric with a calender roll being controlled and spaced from the calender roll is provided to channel air from the actuators over the calender roll. The scoop comprises heat insulating material to prevent heat loss out the back of the scoop. In addition, a plurality of arcuate zone strips are provided on the concave inner surface of the scoop and in substantial alignment with the plurality of actuators for channeling air from the actuators. The arcuate zone strips are spaced apart from one another for thermal separation such that thermal diffusion among longitudinal zones of a calender roll within the scoop are substantially eliminated.

Claims23

Dependent claims

An actuator for controlling one longitudinal zone of a calender roll, said actuator being connected between a pressurized air plenum and said one longitudinal zone which is to be controlled by said actuator which comprises:

an air conducting housing having a proximal end connected to and in communication with said plenum for receiving air from said plenum and a distal end for discharging air from an air outlet of said housing at said one longitudinal zone;
a heater connected within said housing for passing air from said proximal end of said housing toward said distal end of said housing;
and
a valve connected within said housing for controlling the volume of air discharged at said one longitudinal zone in response to air temperature being discharged.

1 more element

A controller for a calender roll with a plurality of longitudinal zones therealong, said controller comprising:

a plurality of actuators corresponding to said plurality of longitudinal zones and being connected between a pressurized plenum and said calender roll, each of said actuators comprising:
an air conducting housing having a proximal end connected to and in communication with said plenum for receiving air from said plenum and a distal end for discharging air from an air outlet of said housing;
a heater connected within said housing for passing air from said proximal end of said housing toward said distal end of said housing;
and
a valve connected within said housing for controlling the volume of air discharged at said air outlet in response to air temperature being discharged;
and
an arcuate scoop extending from the distal ends of said plurality of actuators, said scoop being positioned adjacent and spaced from said calender roll and being substantially concentric therewith for defining an arcuate channel for receiving air from the air outlets of said plurality of actuators, said arcuate scoop having an inner face adjacent said calender roll and an outer face.

4 more elements

Dependencies are inferred from the claim text.

Method and apparatus for throttle valve control of a calender roll actuator

Life of this patent

Method and apparatus for throttle valve control of a calender roll actuator

Life of this patent

Abstract

Claims23