88242361-04-01 Vol 1 DEK TQ TECHNICAL REFERENCE (1).pdfPDFA.pdf - 第168页

10 STENCIL ALIGNMENT MODULE 10.1 OVERVIEW 168 TECHNICAL REFERENCE MANUAL DEK TQ 04/2021 Positioning of the stencil actuators is calculated in the machine software and referenced from the home position. The stencil actuat…

10 STENCIL ALIGNMENT MODULE

10.1 OVERVIEW

TECHNICAL REFERENCE MANUAL DEK TQ 04/2021 167

The chase width is adjustable and can be set to accommodate stencil sizes from 29” (736.6mm) to

550mm. The following most common sized stencils used are engraved on the front and rear of the

chase frame:

●

29” (736.6mm)

●

650mm

●

600mm

●

23” (584.2mm)

●

550mm

NOTE

To prevent a collision with the drip tray a short drip tray (360mm) should be used in conjunction

with a stencil size of 620mm (24.409") or less.

The stencil frame thickness is 25 to 40mm without the stencil clamp adapter.

10.1.2 Alignment Actuators

1 Alignment Actuator Motor 4 Electrical Connection

2 Alignment Actuator Plunger 5 Contact Roller

3 Home Sensor

The actuators are configured in a three-point contact arrangement and are controlled and driven in-

dependently to give maximum flexibility in stencil movement in the X, Y and Theta.

A spring fitted between the machine frame and the chase ensures that the chase is pulled against

the actuator rollers at all times.

10 STENCIL ALIGNMENT MODULE

10.1 OVERVIEW

168 TECHNICAL REFERENCE MANUAL DEK TQ 04/2021

Positioning of the stencil actuators is calculated in the machine software and referenced from the

home position. The stencil actuators only home during initialization, which can be from power-up or

exiting diagnostics. When homing, the stepper motor retracts the actuator plunger until the plunger

reaches the home sensor mounted on the rear of the motor.

10.1.3 Stencil Loading Mechanism

1 Paddle Home Sensor 4 Home Vane

2 Paddle 5 Stencil Presence Sensor

3 Paddle Cylinder 6 Print Carriage

10 STENCIL ALIGNMENT MODULE

10.1 OVERVIEW

TECHNICAL REFERENCE MANUAL DEK TQ 04/2021 169

A stencil is manually loaded into the machine by the operator and the stencil loading mechanism

accurately positions the stencil in the chase. It is incorporated into the print carriage, using a re-

tractable paddle to manoeuvre the stencil backwards and forwards to its correct position.

When Load Stencil is selected, the print carriage drives forward until the rear edge of the stencil is

located by the stencil presence sensor. The print carriage is then driven forwards until it clears the

inner face of the stencil frame. The stencil paddle is lowered, and the print carriage is reversed,

driving the stencil to the rear of the chase. Once in position, the paddle retracts and the print car-

riage drives back by the set ‘hop over distance’, passing over the stencil frame again, the paddle is

lowered and pushes the stencil forwards into the correct position. The paddle is retracted and the

stencil clamps are activated.

The stencil presence sensor, located on the inside of the print carriage, is a photoelectric diffuse

sensor, and has dual functionality. It is used to both confirm the presence of a stencil in the chase,

and to locate the edge of the stencil during the loading procedure.

10.1.4 Stencil Clamps

1 Adjustable Stencil Holder 4 Pneumatic Quick Release Fitting

2 Pneumatic Stencil Clamp 5 Pneumatic Tube

3 Stencil Guide Strip

Once the stencil is in position, it is clamped using a pair of pneumatically operated stencil clamps.

The clamps are hollow rubber bladders and when pneumatic pressure is applied they expand

providing a downward force onto the stencil frame.