US20080099515A1 - Thin line conformal coating apparatus and method - Google Patents
Thin line conformal coating apparatus and method Download PDFInfo
- Publication number
- US20080099515A1 US20080099515A1 US11/558,022 US55802206A US2008099515A1 US 20080099515 A1 US20080099515 A1 US 20080099515A1 US 55802206 A US55802206 A US 55802206A US 2008099515 A1 US2008099515 A1 US 2008099515A1
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Images
Classifications
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/0091—Apparatus for coating printed circuits using liquid non-metallic coating compositions
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
- B05B12/00—Arrangements for controlling delivery; Arrangements for controlling the spray area
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
- B05B12/00—Arrangements for controlling delivery; Arrangements for controlling the spray area
- B05B12/02—Arrangements for controlling delivery; Arrangements for controlling the spray area for controlling time, or sequence, of delivery
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
- B05B12/00—Arrangements for controlling delivery; Arrangements for controlling the spray area
- B05B12/02—Arrangements for controlling delivery; Arrangements for controlling the spray area for controlling time, or sequence, of delivery
- B05B12/06—Arrangements for controlling delivery; Arrangements for controlling the spray area for controlling time, or sequence, of delivery for effecting pulsating flow
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05C—APPARATUS FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05C11/00—Component parts, details or accessories not specifically provided for in groups B05C1/00 - B05C9/00
- B05C11/10—Storage, supply or control of liquid or other fluent material; Recovery of excess liquid or other fluent material
- B05C11/1002—Means for controlling supply, i.e. flow or pressure, of liquid or other fluent material to the applying apparatus, e.g. valves
- B05C11/1015—Means for controlling supply, i.e. flow or pressure, of liquid or other fluent material to the applying apparatus, e.g. valves responsive to a conditions of ambient medium or target, e.g. humidity, temperature ; responsive to position or movement of the coating head relative to the target
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K2201/00—Indexing scheme relating to printed circuits covered by H05K1/00
- H05K2201/09—Shape and layout
- H05K2201/09818—Shape or layout details not covered by a single group of H05K2201/09009 - H05K2201/09809
- H05K2201/09872—Insulating conformal coating
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K2203/00—Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
- H05K2203/01—Tools for processing; Objects used during processing
- H05K2203/0104—Tools for processing; Objects used during processing for patterning or coating
- H05K2203/0126—Dispenser, e.g. for solder paste, for supplying conductive paste for screen printing or for filling holes
Definitions
- the present invention generally relates to applying conformal coating materials and more particularly, to an applicator for applying conformal coatings to electrical components.
- Conformal coating is the process of applying a dielectric material onto an electrical component, for example, a printed circuit (“PC”) board or a device mounted thereon, to protect it from moisture, fungus, dust, corrosion, abrasion, vibration, chemicals, tin whiskers and other environmental stresses.
- Conformal coating materials range from solvent based materials that cure by evaporation of the solvent, to “100% solids” conformal coating materials.
- Common conformal coating materials include silicones, acrylics, urethanes, epoxy synthetic resins, paralyne and various polymers.
- Automated selective coating systems which have conformal coating dispensers that dispense material in various patterns, with varying deposition accuracies and producing coatings with varying thicknesses.
- a dispenser may dispense material in the form of a straight bead, a bead that is continuously rotated in a curved or circular pattern, and/or a bead that is subsequently atomized. Beads tend to produce coatings that are generally thicker than those for atomized sprays.
- a bead deposited on a board may spread to locations where no coating is desired.
- injecting a supply of material with pressurized air to achieve atomization often creates significant overspray, thus depositing atomized droplets outside a target area.
- Known needle valve dispensers control dispensing of a conformal coating material by controlling a time that a needle valve is open as well as an applied pressure of the conformal coating material being supplied to the needle valve.
- Such known needle valve dispensers also have some short comings, for example, first, it is difficult to control a flow of lower viscosity conformal coating materials. While there is no standard measure that distinguishes lower viscosity materials from higher viscosity materials, as an example, lower viscosity materials include but are not limited to materials that have viscosities that are less than one thousand centipoise.
- the dispensing tip In order to reduce splash of lower viscosity materials through known needle valve dispensers, the dispensing tip must be maintained as close to the surface of the substrate as possible, for example, within several millimeters (“mm”). On PC boards that are densely populated, the requirement that the dispensing tip be maintained so close to the substrate surface may severely limit the application of known needle valve dispensers.
- the inability of known needle valve dispensers to sharply cutoff a flow of conformal coating material results in dripping, drooling, poor flow control and generally, a less precise application. For example, the coating material can only be applied to within about 0.060 inch (“in”) or about 1.5 mm of a keep-out area, that is, an area where no conformal coating material is to be applied.
- known needle valve dispensers have an inherent problem of allowing coating materials to cling to, and partially cure on, the dispensing tip, which leads to clogs and may reduce the repeatability and accuracy of the dispensing process.
- the present invention provides a coating system with a needle valve applicator that may apply lower viscosity conformal coating materials to a substrate with greater accuracy, precision and/or speed than known needle valve applicators and/or may have other advantages.
- the coating system of the present invention may improve the ability of a needle valve applicator to apply coating material closer to keep-out areas, and/or apply thinner lines of coating material, and/or operate higher above a substrate while maintaining a desired accuracy in the placement of the conformal coating material on the substrate.
- Such improved coating system performance often eliminates masking and unmasking, thereby substantially reducing handling of the substrate.
- a coating system of the present invention can provides a needle valve applicator that cleanly ejects coating material from a dispensing needle, thereby preventing the coating material from clinging to, and/or curing on, the dispensing needle. This reduces maintenance and minimizes clogs while maintaining accuracy and increasing repeatability.
- the coating system of the present invention may allow for coating material discharge volumes that are predictable and repeatable; and therefore, a total volume of conformal coating material applied over an area may be precisely controlled. Such a capability can substantially reduce waste of the conformal coating material.
- the coating system of the present invention may provide a needle valve applicator that has a slim profile and thus, can be moved through small spaces between components on PC boards at lower dispense heights, which minimizes splashing when coating with lower viscosity materials. All of the features above can make the coating system of the present invention especially useful when applying a conformal coating material to smaller, densely populated PC boards.
- the invention provides a coating system with a applicator that has an air cylinder operated by a solenoid connected to pressurized air.
- a needle valve mounted in the cylinder is opened by the solenoid applying pressurized air to a piston connected to the needle valve.
- a control has a timer that is operable to provide a string of electrical pulses to the solenoid. With each pulse, the solenoid applies the pressurized air to the piston, thereby opening the needle valve and permitting coating material to flow past the needle valve.
- the needle valve is closed for durations of time between pulses, and the coating material is ejected from a dispensing needle in response to closings of the needle valve.
- the timer is a pulse width modulator; and the needle valve is repeatedly opened for durations about equal to an On time stored in the control.
- the needle valve is closed by a return spring and held closed for durations of time between the pulses.
- the invention provides a method of automatically dispensing a coating material onto a substrate with an applicator being movable by a programmable control operating a positioner supporting the applicator.
- the applicator has a flow channel conducting a coating material from a needle valve to a dispensing needle.
- the needle valve is movable to an open position by an air cylinder piston in response to a pressurized fluid received from a solenoid, and the needle valve is then movable to a closed position.
- the method includes applying a string of electrical pulses to the solenoid.
- the coating material is moved past the needle valve by repeatedly opening the needle valve in response to each pulse in the string of electrical pulses being applied to the solenoid.
- the coating material is ejected from the dispensing needle by repeatedly closing the needle valve in response to periods of time between pulses in the string of electrical pulses.
- FIG. 1 is a schematic block diagram of one exemplary embodiment of a computer controlled conformal coating system.
- FIG. 2 is a disassembled view of an exemplary embodiment of a conformal coating applicator used in the conformal coating system of FIG. 1 .
- one exemplary example of a conformal coating system 20 includes a conformal coating applicator or dispenser 22 mechanically suspended from an X-Y-Z positioner 24 .
- the X-Y-Z electro-mechanical positioner 24 includes a drive coupled to independently controllable motors (not shown) in a known manner.
- the X-Y-Z positioner 24 is capable of rapidly moving the conformal coating applicator 22 with respect to a substrate 26 .
- a computer 28 may be a programmable logic controller (“PLC”), a microprocessor based controller, a hardened personal computer or other conventional programmable control device capable of carrying out the functions described herein as will be understood by those of ordinary skill.
- a user I/O 30 for example, a visual display device such as an LCD screen (not shown) and a user input device such as a keyboard (not shown) are connected to the computer 28 in a known manner.
- the computer provides outputs to a timer 49 , for example, a pulse width modulator (“PWM”) 50 , that, in turn, is electrically connected to, and drives, an air solenoid 140 .
- PWM 50 creates a series or string of electrical control pulses that are used to operate the solenoid 140 and hence, the conformal coating applicator 22 .
- the computer 28 has a memory 52 for storing operating programs and programmed instructions in a known manner.
- the memory further includes On time storage 54 and Cycle time storage 56 .
- the On time storage stores at least one desired value of an On time of a pulse in a pulse string created by the PWM 50 .
- the Cycle time storage stores at least one desired value of a respective total Cycle time associated with the On time of the pulse.
- a pulse Off time is determined by subtracting a stored On time from a stored respective Cycle time.
- the coating system 20 is provided with one or more standard RS-232 busses 32 and one or more SMEMA communications busses 34 , which are compatible with most types of other automated equipment utilized in substrate production assembly lines.
- the motion controller 40 and a conveyor controller 42 are in electrical communications with the computer 28 and with each other.
- a system control includes the computer 28 , the PWM 50 , the motion controller 40 , the applicator control 38 and the conveyor controller 42 , if used.
- the substrate 26 for example, a PC board, onto which a conformal coating is to be applied, is supported in an operative relationship with the conformal coating applicator 22 in a known manner.
- one or more substrates 26 may be coated in a batch mode; or optionally, the substrates 26 may be moved continuously past the applicator 22 by a conveyor 36 .
- the conveyor 36 is of a conventional design and has a width which may be adjustable to accept PC boards of different dimensions.
- the conveyor 36 may also include pneumatically operated stop and locate mechanisms, and the conveyor 36 is operated by a conveyor controller 42 in a known manner.
- the exemplary embodiment may further include a nozzle dressing station 44 that includes one or several soak cups 46 , a purge cup 48 and/or other nozzle dressing tools that can be used to clean an applicator tip in a known manner depending on the specific properties of the conformal coating used.
- the conformal coating applicator 22 has a packing cartridge 66 that supports a piston rod 70 , which is inserted into a bore 68 of an air cylinder body 62 .
- An air cylinder piston 72 , thrust bearing 74 , O-ring 76 and lock nut seal 78 are then mounted on the piston rod 70 .
- a lock nut 80 is then threaded onto a piston rod end 82 to secure the air cylinder piston 72 , thrust bearing 74 , O-ring 76 and lock nut seal 78 onto the piston rod 70 to form a unitary piston assembly 73 with respect to the air cylinder 62 .
- O-ring 76 seals the packing cartridge 66 within the air cylinder 62 .
- O-ring 85 seals the pressurized coating material within the cylinder bore 68
- O-ring 84 seals the pressurized air within the cylinder bore 68
- An air cylinder cap 60 is threadedly mounted on the air cylinder 62 with an O-ring 64 providing a seal resistance to rotation of the cap 60 .
- a mounting bracket 126 is attached to the air cylinder 62 by fasteners 128 , and the mounting bracket 126 may be used to mount the applicator 22 to the positioner 24 of FIG. 1 .
- the piston assembly 73 is moveable lengthwise with respect to the packing cartridge 66 .
- the piston assembly 73 moves to the right as viewed in FIG. 2 , which motion compresses a return spring 88 that is secured over the piston rod 70 by a nut 94 .
- the return spring 88 Upon the pressurized air being removed from the pneumatic piston 72 , the return spring 88 returns the piston assembly 73 to its original longitudinal position with respect to the air cylinder 62 .
- a needle valve 91 has a needle 92 and a mating seat 96 .
- the needle 92 is threaded onto an opposite piston rod end 94 and thus, is movable by the piston assembly 73 .
- a seat 96 is mounted to one end of the air cylinder 62 by a mounting plate or cap 98 that is secured by a fasteners 100 .
- An O-ring 102 provides a fluid seal between the seat 96 and the air cylinder 62 .
- the bore 68 is fluidly coupled via connector 144 to pressurized air that fills the bore 68 between the O-ring 84 and the piston 72 .
- the bore 68 is also fluidly coupled via connector 138 to a pressurized source of conformal coating material that fills the bore 68 between the O-ring 85 and seat 96 .
- the seat 96 has a flow channel 97 throughwhich the conformal coating material passes when the needle valve 91 is open.
- the air cylinder cap 60 has a scale marked on its circumference, and rotating the cap 60 provides a microadjustment of a positive stop that limits a displacement of the piston assembly 73 and hence, the needle 92 when the needle valve 91 is opened.
- the air cylinder cap 60 provides a control of conformal coating material through the needle valve 91 .
- a nozzle adaptor 104 extends through a bore 106 of the mounting cap or plate 98 and is threaded onto one end 107 of the seat 96 .
- a holder 108 has one end 109 threaded into the nozzle adaptor 104 .
- a capillary tube 110 has one end 112 threaded into the holder 108 .
- a dispensing needle 116 is inserted into an end 122 of a retaining nut 120 , which has a larger bore that accepts a hub 117 of the dispensing needle 116 . Thus, only a tip 119 of the dispensing needle 116 extends through a smaller bore at an opposite end 118 of the retaining nut 120 .
- An opposite end 114 of the capillary tube 110 slides into a bore of a dispensing needle 116 , and the retaining nut end 122 is threaded to an end 124 of the holder 108 , thereby securing the dispensing needle 116 to the applicator 22 .
- a pressurized air supply 130 provides an air pressure VP, for example, a shop air pressure, to a pressure regulator 132 that may be mounted on the conformal coating applicator 22 .
- a gage 133 monitors the regulated air pressure applied to a solenoid 140 , and an air line 142 conducts the regulated pressurized air from the solenoid 140 to an air fitting 144 connected to the air cylinder body 62 .
- the pressurized air supply 130 further provides an air pressure FP to a pressure regulator 146 that may be mounted on the positioner 24 and thus, does not move with the applicator 22 .
- a gage 147 monitors the regulated air pressure that is applied to a liquid reservoir 148 .
- the liquid reservoir 148 may be a syringe of conformal coating material that is commercially available from a supplier, the regulated air pressure from the pressure regulator 146 may be applied to a plunger located in one end of the syringe. Thus, the liquid reservoir 148 supplies a pressurized conformal coating material to the air cylinder 62 .
- the pressure regulator may be adjusted to change the pressure of the conformal coating material supplied from the reservoir 148 to the air cylinder 62 .
- a user In operation, prior to initiating a conformal coating application cycle, a user must set up the coating system 20 for a particular application. In that process, desired values for system variables are determined; and those desired values are often application dependent. For example, desired values for system variables may depend on the conformal coating material being used, its viscosity, the specifications of the conformal coating as applied to the substrate, current environmental conditions, desired applicator velocity and similar factors.
- One variable value that the user may select is a general size of droplet to be applied by the dispensing needle 116 .
- Dispensing needles may be selected that have respective internal flow paths of different diameters; and hence, larger dispensing needles may be chosen to provide larger droplets and smaller dispensing needles may be chosen when smaller droplets are desired.
- the user may also determine a PWM On time, a PWM Cycle time and a desired material flow through the needle valve 91 . Again, the desired values for those variables are application dependent.
- the material flow through the needle valve 91 may be adjusted by turning or microadjusting the air cylinder cap 60 shown in FIG. 2 , which is effective to adjust the open position or stroke of the needle 92 .
- Material flow through the needle valve 91 may also be varied by changing the pressure on the conformal coating material by adjusting regulated air pressure from the pressure regulator 146 . Often, a number of test substrates are coated, and the variables adjusted until a desired coating application is obtained.
- the positioning program provided by the motion controller 40 may also be changed depending on various setup factors, for example, how high the dispensing tip 119 can be raised from the substrate 26 and still provide a conformal coating within specifications.
- a table of starting default values of regulated air pressures from pressure regulator 146 , air cylinder cap adjustments and On time and Cycle time values may be stored in memory 50 of the computer 28 .
- the user I/O 30 may be used to set and adjust the values in the On time storage 54 and the Cycles time storage 56 .
- the gages 133 , 147 may have visual displays and the pressure regulators 132 , 146 may be manually adjustable.
- the gages 133 , 147 may provide respective pressure feedback signals to the computer 28 ; and the pressure regulators 132 , 146 may have inputs permitting the computer 28 to change and set the respective regulated pressures.
- the memory 52 may provide On time storage 54 , Cycle time storage 56 , regulated coating material pressure storage 57 and regulated valve pressure storage; and the values stored in the memory 52 may be set and/or changed by the user operating the user I/O 30 .
- the user I/O may be used to initiate an automatic cycle of operation.
- Data representing a desired dispensing cycle is stored in the memory 50 of the computer 28 that, in turn, communicates control signals to the motion controller 40 .
- the motion controller 40 commands the X-Y-Z positioner 24 to move the applicator 22 to desired locations with respect to the substrate 26 .
- the motion controller 40 provides a command signal to the computer 28 that, in turn, operates the PWM 50 with the desired On times and Cycle times.
- the PWM 50 provides a pulse to the solenoid 140 causing it to change state and apply a regulated valve air pressure to piston surface 86 ( FIG. 2 ).
- the valve air pressure causes the piston assembly 73 and needle 92 to overcome the biasing force of the piston return spring 88 and move to the right as viewed in FIG. 2 . That motion displaces the needle 92 away from the seat 96 , thereby opening the needle valve 91 for a duration of the On time.
- conformal coating material may flow through a downstream flow path, that is, a flow path through the seat flow channel 97 , the holder 108 , the capillary tube 110 and the dispensing needle 116 .
- the coating material pressure and needle open position are set, so that when the needle valve 91 is open, a volume of conformal coating material flows past the needle valve 91 , which is about equal to the volume of conformal coating material most recently ejected from the dispensing needle 116 .
- the solenoid 140 switches back to its original state; and the valve air pressure is removed from the air cylinder piston 72 .
- the time between two pulse On times is defined as a pulse Off time; and during the pulse Off time, the piston return spring 88 rapidly moves the piston 72 and needle 92 to the left, as viewed in FIG. 2 , until the needle 92 again engages the seat 96 , thereby closing the needle valve 91 and terminating the flow of conformal coating material past the needle valve 91 .
- the rapid return action of the needle 92 creates a pressure spike in the downstream flow path, which causes a droplet of conformal coating material to be sharply discharged from the dispensing needle 116 .
- the pressure spike is effective to cleanly eject the droplet of conformal coating material from the dispensing needle tip 119 , thereby substantially preventing conformal coating material from clinging to the dispensing needle 116 .
- the computer 28 again operates the PWM 50 to produce a pulse to the solenoid 140 with the desired On time.
- the PWM 50 provides a stream or string of pulses rapidly opens and closes the needle valve 91 over very short time periods to eject droplets of conformal coating material from the dispensing tip 119 .
- the droplets may be dispensed close to each other so that they stitch together to form a line of conformal coating material, and the lines can be dispensed close to each other to apply the conformal coating material over an area.
- the net result is a conformal coating system that applies lower viscosity conformal coating materials to a substrate with greater accuracy, precision and speed than known needle valve applicators.
- using the PWM 50 permits the applicator 22 to apply a conformal coating material to within about 0.040 in (1 mm) of a keep-out area and apply a coating material in line widths that are about 0.050 in (1.2 mm) wide with highly distinctive edges.
- the dispensing tip 119 may be elevated up to about 0.480 in (12 mm) above the substrate 26 while maintaining a desired accuracy in the placement of the conformal coating material on the substrate.
- Such improved performance often eliminates masking and unmasking, thereby substantially reducing handling of the substrate 26 .
- such improved performance often permit the applicator 22 to be moved at higher velocities and through conformal coating cycles that take less time and are more efficient than coating cycles executed with known needle valve applicators.
- the rapid pulsing of the needle valve in the conformal coating system causes the droplets of conformal coating material to be ejected cleanly from the dispensing needle tip, thereby preventing conformal coating material from clinging to, and/or curing on, the dispensing needle tip 119 .
- the dispensing of droplets by the needle valve 91 provides a droplet volume that is predictable and repeatable; and therefore, the volume of conformal coating material applied over an area can be precisely controlled by the computer 28 and motion controller 40 .
- the motion controller 40 may be used to control the velocity of the applicator 22 .
- the computer 28 may be used to control material flow by appropriate selection of an On time and/or selecting a number of times that the PWM 50 cycles the needle valve 91 while the applicator 22 is moving over an area of the substrate 26 . Such a capability substantially reduce waste of the conformal coating material.
- the conformal coating system provides a slim profile for the holder 108 , the retaining nut 120 and the dispensing needle tip 119 , which permits the applicator 22 to moved through small spaces between components on PC boards at lower dispense heights.
- This design optimizes dispensing selectivity when coating with lower viscosity materials. All of the features above make the conformal coating system 10 shown and described herein especially useful when applying a conformal coating material to smaller and densely populated PC boards.
- the timer 49 is a PWM 50 .
- other timing circuits or devices may be used that are operative to provide a string of pulses to the solenoid 140 , wherein the time the solenoid 140 is operated to hold the needle valve 91 open is adjustable.
- the timer 49 is shown as a separate component. In other embodiments, the timer 49 may located anywhere that is appropriate for the design.
- the timer 49 may be a stand-alone programmable or nonprogrammable device, or be a programmable or nonprogrammable component integrated into the I/O of the computer 28 or the motion controller 40 , or be implemented in software in the computer 28 or the motion controller 40 .
- the On time of the PWM 50 is used to operate the solenoid 140 to hold the needle valve 91 open.
- an Off time of the PWM 50 may be used.
- the PWM On time and Cycle time are adjustable by a user and stored in a memory 52 .
- the Cycle time may be fixed and only the On time may be adjustable and stored.
- only the Off time may be adjustable and stored; or the On time and the Off time may be adjustable and stored; or the Off time and the Cycle time may be adjustable and used.
- a pressurized air supply 130 is used to drive the solenoid 140 and apply a regulated pressure to the reservoir 148 .
- other pressurized fluids or gases may be used instead of air.
- the coating system 10 may be used to apply other coating materials to the substrate 26 .
- the coating system 10 has a control that utilizes motion controller 40 and computer 28 ; however, in other embodiments, the control functions discussed herein may be implemented using fewer or more programmable controllers or devices that may be in different locations. Often, application requirements and the availability of resources at different facilities will require different control configurations.
- a return spring 88 is used to close the needle valve 88 ; however, in an alternative embodiment, the air cylinder 62 may be a double acting cylinder and operable to move the needle 92 to a closed position.
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Priority Applications (6)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US11/558,022 US20080099515A1 (en) | 2006-10-11 | 2006-11-09 | Thin line conformal coating apparatus and method |
JP2007261035A JP2008093659A (ja) | 2006-10-11 | 2007-10-04 | 細線コンフォーマルコーティング装置及び方法 |
DE102007048651A DE102007048651A1 (de) | 2006-10-11 | 2007-10-10 | Beschichtungseinrichtung zur konformen Dünnlinien-Beschichtung sowie Verfahren dazu |
CN2007101807304A CN101161357B (zh) | 2006-10-11 | 2007-10-11 | 细线保形涂敷设备和方法 |
US12/426,572 US8545931B2 (en) | 2006-10-11 | 2009-04-20 | Thin line conformal coating method |
JP2014109329A JP5887689B2 (ja) | 2006-10-11 | 2014-05-27 | 細線コンフォーマルコーティング装置及び方法 |
Applications Claiming Priority (2)
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US82904906P | 2006-10-11 | 2006-10-11 | |
US11/558,022 US20080099515A1 (en) | 2006-10-11 | 2006-11-09 | Thin line conformal coating apparatus and method |
Related Child Applications (1)
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US12/426,572 Division US8545931B2 (en) | 2006-10-11 | 2009-04-20 | Thin line conformal coating method |
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US20080099515A1 true US20080099515A1 (en) | 2008-05-01 |
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US12/426,572 Active 2028-03-26 US8545931B2 (en) | 2006-10-11 | 2009-04-20 | Thin line conformal coating method |
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US12/426,572 Active 2028-03-26 US8545931B2 (en) | 2006-10-11 | 2009-04-20 | Thin line conformal coating method |
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US (2) | US20080099515A1 (ja) |
JP (2) | JP2008093659A (ja) |
CN (1) | CN101161357B (ja) |
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US20100109175A1 (en) * | 2008-10-31 | 2010-05-06 | Pugh Randall B | Processor controlled ophthalmic device |
US20100110372A1 (en) * | 2008-10-31 | 2010-05-06 | Pugh Randall B | Ophthalmic device with embedded microcontroller |
US20100321897A1 (en) * | 2009-06-17 | 2010-12-23 | Laird Technologies, Inc. | Compliant multilayered thermally-conductive interface assemblies |
US20100321895A1 (en) * | 2009-06-17 | 2010-12-23 | Laird Technologies, Inc. | Memory modules including compliant multilayered thermally-conductive interface assemblies |
US20120040088A1 (en) * | 2006-06-28 | 2012-02-16 | Nordson Corporation | Systems and methods for applying a liquid coating material to a substrate |
US20130026198A1 (en) * | 2010-01-27 | 2013-01-31 | Robatech Ag | Electric application head for dispensing a free-flowing medium, and device comprising such an electric application head |
US20190133384A1 (en) * | 2017-11-06 | 2019-05-09 | Gojo Industries, Inc. | Touch-free dispensers |
US10794540B2 (en) | 2016-10-14 | 2020-10-06 | Marco Systemanalyse Und Entwicklung Gmbh | Apparatus and method for applying a fluid to an object surface |
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US20120040088A1 (en) * | 2006-06-28 | 2012-02-16 | Nordson Corporation | Systems and methods for applying a liquid coating material to a substrate |
US8545929B2 (en) * | 2006-06-28 | 2013-10-01 | Nordson Corporation | Method for applying a liquid coating material to a substrate |
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Also Published As
Publication number | Publication date |
---|---|
JP2014193468A (ja) | 2014-10-09 |
CN101161357B (zh) | 2013-06-12 |
US20090202709A1 (en) | 2009-08-13 |
JP2008093659A (ja) | 2008-04-24 |
US8545931B2 (en) | 2013-10-01 |
CN101161357A (zh) | 2008-04-16 |
DE102007048651A1 (de) | 2008-04-17 |
JP5887689B2 (ja) | 2016-03-16 |
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Legal Events
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AS | Assignment |
Owner name: NORDSON CORPORATION, OHIO Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:SZUCH, MICHAEL;REEL/FRAME:018595/0055 Effective date: 20061027 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |