Lift tool assembly for stencil printer

Patent metadata

Field	Value
Publication number	US-9868278-B2
Application number	US-201615182215-A
Country	US
Kind code	B2
Filing date	Jun 14, 2016
Priority date	Apr 7, 2015
Publication date	Jan 16, 2018
Grant date	Jan 16, 2018

Abstract

A stencil printer includes a frame, a stencil coupled to the frame, and a print head coupled to the frame to deposit and print viscous material over the stencil. The stencil printer further includes a lift table assembly configured to support the substrate in a transport position and a print position, and a conveyor system. The conveyor system includes a pair of rail members coupled to the frame. The pair of rail members extends through the frame and is configured to transport the substrate through the stencil printer. The conveyor system further includes, for each rail member, a lift tool assembly coupled to the rail member. The lift tool assembly is configured to cooperate with the lift table assembly and to engage and support the substrate at a transport height and a print height.

First claim

What is claimed is:

1. A method for supporting and clamping a substrate in a print position during a print operation of a stencil printer, the method comprising:
moving the substrate on a conveyor system having a pair of rails at a transport height over a lift table assembly;
clamping opposite edges of the substrate; and
moving the substrate in a z-axis direction with a lift tool assembly coupled to each rail member,
wherein for each rail member, the lift tool assembly is movable with respect to the rail member, the lift tool assembly being configured to cooperate with the lift table assembly and to engage and support the substrate at a transport height and a print height, the lift tool assembly including a lifter portion configured to be engaged by a support of the lift table assembly and a modular clamping subassembly coupled to the lifter portion, the modular clamping subassembly including a backplane mounted on a top of the lifter portion, the backplane having a linear bearing mounted on a back of the backplane to provide a degree of freedom for clamping.

2. The method of claim 1 , wherein the substrate is configured to move between a transport height position, a vision system clearance height position and a print height position.

3. The method of claim 2 , further comprising locating a pin associated with the lift tool assembly into a locator associated with the rail member when moving the substrate to the transport height position.

4. The method of claim 1 , wherein the lifter portion includes a foot that extends under the rail member, the foot being configured to be engaged by the support of the lift table assembly.

5. The method of claim 4 , wherein the foot of the lifter portion contains permanent magnets to couple to the support of the lift table assembly.

6. The method of claim 1 , wherein the modular clamping subassembly further includes an L-shaped plate mounted on the linear bearing.

7. The method of claim 6 , wherein the L-shaped plate is configured with a clamping assembly on which flexible steel foils clamp substrate.

8. The method of claim 7 , wherein a clamping force on the substrate is provided by several pneumatic cylinders.

9. The method of claim 1 , wherein the backplane of the modular clamping subassembly includes a pin configured to be positioned within a locator associated with the rail member.

Assignees

• Illinois Tool Works

Inventors

• Mariano Daniel

Classifications

• B41P2215/50

  Screen printing machines for particular purposes · CPC title

• H05K3/1233

  Methods or means for supplying the conductive material and for forcing it through the screen or stencil · CPC title

• B41F15/18 Primary

  Supports for workpieces · CPC title

• H05K3/1216

  by screen printing or stencil printing · CPC title

• B41F15/0881 Primary

  for printing on polyhedral articles · CPC title