Apparatus and methods for dispensing small beads of viscous material

Patent metadata

Field	Value
Publication number	US-10124303-B2
Application number	US-201514826534-A
Country	US
Kind code	B2
Filing date	Aug 14, 2015
Priority date	Sep 5, 2014
Publication date	Nov 13, 2018
Grant date	Nov 13, 2018

Abstract

Apparatus and methods for dispensing small beads of a viscous, mixed fluid material formed by first and second viscous fluids. The apparatus includes first and second metering rods for moving in a reciprocating manner, such that the first metering rod extends into a first fluid passageway, and the second metering rod extends into a second fluid passageway. A mixing passage communicates with the first and second fluid passageways to receive the first and second viscous fluids from the first and second fluid passageways. A dispensing passageway is in fluid communication with the mixing passage, and dispenses a small bead of viscous, mixed fluid material formed by the mixed first and second viscous fluids. A control retracts the first and second metering rods to prevent drooling of the viscous, mixed fluid material from the dispensing passageway after a dispensing cycle.

First claim

What is claimed is:

1. An apparatus for dispensing small beads of a viscous, mixed fluid material formed by first and second viscous fluids, the apparatus comprising:
a fluid dispensing body including a first fluid passageway and a second fluid passageway;
first and second metering rods, the first metering rod extending into the first fluid passageway, and the second metering rod extending into the second fluid passageway, the first and second metering rods extending into the first and second fluid passageways, respectively, in a dispense direction;
a mixing passage including a mixer, the mixing passage communicating with the first and second fluid passageways to receive the first and second viscous fluids from the first and second fluid passageways when the first and second metering rods are moved into the first and second fluid passageways;
a rotary valve positioned between the first and second metering rods and the mixing passage, the rotary valve having a single valve body that defines a first rotary passage and a second rotary passage, both the first rotary passage and the second rotary passage including a dispense portion that extends through the rotary valve and a recharge portion that extends from an exterior of the rotary valve to the dispense portion, the rotary valve configured to rotate between a first position, allowing fluid communication between the first fluid passageway and the mixing passage via the dispense portion of the first rotary passage in the dispense direction and allowing fluid communication between the second fluid passageway and the mixing passage via the dispense portion of the second rotary passage in the dispense direction, and a second position, preventing fluid communication between the first and second fluid passageways and the mixing passage;
a dispensing passageway in fluid communication with the mixing passage, and configured to dispense a small bead of viscous, mixed fluid material formed by the mixed first and second viscous fluids; and
a control configured to extend and retract the first and second metering rods, and further configured to rotate the rotary valve between the first position and the second position.

2. The apparatus of claim 1 , further comprising:
a carriage support;
a carriage mounted for moving in a reciprocating manner relative to the carriage support; and
an actuator coupled to the carriage for moving the carriage in the reciprocating manner,
wherein the first and second metering rods are coupled to the carriage for simultaneously moving in the reciprocating manner, the mixing passage communicates with the first and second fluid passageways to receive the first and second viscous fluids from the first and second fluid passageways when the first and second metering rods are simultaneously moved into the first and second fluid passageways by actuation of the carriage with the actuator, and the control is coupled to the actuator.

3. The apparatus of claim 1 , wherein the control is further configured to simultaneously retract the first and second metering rods before rotating the rotary valve between the first position and the second position.

4. The apparatus of claim 1 , wherein the first and second metering rods and the first and second fluid passageways are sized to dispense the first and second viscous fluids in a ratio exceeding 1:1.

5. The apparatus of claim 4 , wherein the ratio is between 1:1 and 10:1.

6. The apparatus of claim 1 , wherein the dispensing passageway is sized to dispense a minute bead of the viscous, mixed fluid material with a diameter of 0.2 to 0.4 mm.

7. The apparatus of claim 1 , wherein the ratio of the total passageway volume upstream of the mixing passage to the dispensed volume is 200:1 or less.

8. The apparatus of claim 1 , wherein the first metering rod has a diameter that is different from a diameter of the second metering rod.

9. The apparatus of claim 1 , wherein the first fluid passageway is parallel to the second fluid passageway.

10. The apparatus of claim 1 , further comprising:
a first downstream passageway being positioned between the first fluid passageway and the mixing passage, the first downstream passageway being angled relative to the first fluid passageway; and
a second downstream passageway being positioned between the second fluid passageway and the mixing passage, the second downstream passageway being angled relative to the second fluid passageway.

11. The apparatus of claim 10 , wherein the angle between the first downstream passageway and the first fluid passageway is obtuse, and wherein the angle between the second downstream passageway and the second fluid passageway is obtuse.

12. The apparatus of claim 11 , wherein the angle between the first downstream passageway and the first fluid passageway is equal to the angle between the second downstream passageway and the second fluid passageway.

13. The apparatus of claim 1 , wherein the recharge portion of the first rotary passage is perpendicular to the dispense portion of the first rotary passage, and wherein the recharge portion of the second rotary passage is perpendicular to the dispense portion of the second rotary passage.

14. A method for dispensing small beads of a viscous, mixed fluid material formed by first and second viscous fluids, the method comprising:
moving first and second metering rods respectively into first and second fluid passageways to direct the first and second viscous fluids from the first and second fluid passageways into a mixing passage, the first and second metering rods directing the first and second viscous fluids in a dispense direction;
mixing the first and second viscous fluids with a mixer in the mixing passage;
dispensing a small bead of viscous, mixed fluid material formed by the mixed first and second viscous fluids;
retracting the first and second metering rods by a distance sufficient to cut off the dispensing of the small bead and prevent drooling of the viscous, mixed fluid material; and
after retracting the first and second metering rods, rotating a valve positioned between the first and second metering rods and the mixing passage from a first position to a second position, the valve having a single valve body that defines a first rotary passage and a second rotary passage, both of the first rotary passages and the second rotary passages including a dispense portion that extends through the valve and a recharge portion that extends from an exterior of the valve to the dispense portion, wherein in the first position, fluid communication is allowed between the first fluid passageway and the mixing passage via the dispense portion of the first rotary passage in the dispense direction and fluid communication is allowed between the second fluid passageway and the mixing passage via the dispense portion of the second rotary passage in the dispense direction, and wherein in the second position, fluid communication is prevented between the first and second fluid passageways and the mixing passage.

15. The method of claim 14 , wherein moving first and second metering rods includes simultaneously moving first and second metering rods and retracting the first and second metering rods includes simultaneously retracting the first and second metering rods.

16. The method of claim 14 , wherein the first and second viscous fluids are directed from the first and second fluid passageways in a ratio exceeding 1:1.

17. The method of claim 16 , wherein the ratio is between 1:1 and 10:1.

18. The method of claim 14 , wherein the small bead of the viscous, mixed flui

Assignees

• Nordson Corp

Inventors

• Britcher James
• Groat David W
• Tudor Thomas R
• Turner Jr Herman E

Classifications

• B05B7/12

  designed to control volume of flow, e.g. with adjustable passages · CPC title

• B05C5/0237

  Fluid actuated valves · CPC title

• B05C5/0225

  characterised by flow controlling means, e.g. valves, located proximate the outlet (B05C5/0258, B05C5/0275 take precedence; supply valves upstream the coating head B05C11/1036) · CPC title

• G01F11/021

  of the piston type (G01F11/04 takes precedence) · CPC title

• B05C11/1036

  Means for supplying a selected one of a plurality of liquids or other fluent materials, or several in selected proportions, to the applying apparatus · CPC title