Illinois Tool Works Inc.

Boston Digital Corporation

John George Klauser

Dennis G Doyle

Patsy Anthony Mattero

James J Lynch

Kenneth J King

Joseph A Perault

Ronald J Forget

A stencil printer for printing viscous material on an electronic substrate includes a stencil having apertures formed therein, and a print head positioned over the stencil and configured to deposit viscous material within the apertures of the stencil. The print head includes a housing defining an elongate chamber, a source port defining a passage having an inlet positioned to allow viscous material to flow into the elongate chamber, a pair of blades defining a slot that provides an outlet from which viscous material can flow out of the elongate chamber, an elongate plunger movable in the elongate chamber to reduce a volume of viscous material within the elongate chamber, and at least one sensor to detect pressure of the viscous material within the elongate chamber.

Print head for stencil printer

A control apparatus for multiplexing a single distributed control amplifier to control multiple axes of motion in a multi-axis machine. In one example, the control apparatus comprises a distributed control motor amplifier, a first motor constructed and arranged to provide movement along a first axis of motion, a second motor constructed and arranged to provide movement along a second axis of motion, a first relay having a switch coupled to the distributed control motor amplifier, a first contact coupled to the first motor, a second contact coupled to the second motor, and an input for receiving an actuation signal, wherein the relay is configured to be manipulated between a first state in which the switch is electrically connected to the first contact a second state in which the switch is electrically connected to the second contact, in response to the actuation signal.

Multiplexed control of multi-axis machine with distributed control amplifier

A stencil printer for printing viscous material on a substrate includes a frame, a stencil, and a print head to deposit and print viscous material over the stencil. A substrate support supports a substrate in a print position. A substrate support movement assembly includes a first movement mechanism configured to move the substrate support in a first direction, a second movement mechanism configured to move the substrate support in a second direction, the second direction being generally perpendicular to the first direction, and a third movement mechanism, spaced from a first movement mechanism, configured to move the substrate in the first direction. The stencil printer further includes a controller coupled to the substrate support movement assembly to move the substrate support by the first, second and third movement mechanisms in an x-direction, a y-direction and a rotational direction to align the substrate.

Method and apparatus for adjusting a substrate support

Stencil printer with multiplexed control of multi-axis machine having distributed control motor amplifier

A digital control system is provided for regulating the position and velocity of a load. Within the control system, both commanded and actual motion of the load are represented by a bi-directional pulse train in which each pulse represents an increment of movement, so that the pulse repetition rate represents the speed of the load. A bi-directional pulse generator is provided in which the polarity and repetition rate of the output signal are dependent respectively on the sign and magnitude of the differential pulse accumulation between the commanded and actual motion signals. In one embodiment, a pulse-actuated incremental stepping motor is used to move the load, so that the bi-directional pulse train from the pulse generator can be applied directly to the stepping motor through a pulse conditioner, and is also fed back through a single feedback connection as the actual motion signal. In a second embodiment of the system, a motor requiring an analog drive signal is used and the system has two feedback paths for a bi-directional pulse signal produced by a transducer in response to the actual movement of the load. In the first path, there is accumulated the difference between the number of pulses in the transducer signal and the number of pulses in an externally applied command signal to produce a positional error signal. The positional error signal is applied to a pulse generator to control the polarity and repetition rate of bi-directional output pulses produced by the pulse generator. The output pulses from the pulse generator are used as the command signal for the second feedback path in which there is accumulated the difference between the number of pulses in the pulse generator signal and the transducer signal to produce a second error signal. The second error signal is applied to a digital-to-analog converter which provides an analog signal for controlling the speed of the motor that moves the load. In a third embodiment, a plurality of subsystems, each of the type described above, are combined to form a system for controlling the position and motion of the load along a plurality of coordinates.

Growing community of inventors

Holliston, MA, United States of America

John George Klauser