Two-component dispensing gun

• US 6,345,776 B1
• Filed: 12/23/1999
• Issued: 02/12/2002
• Est. Priority Date: 12/23/1999
• Status: Expired due to Term

• Current Assignee: ICP Construction, Inc. (Innovative Chemical Products Group LLC)
• Original Assignee: Fomo Products, Inc. (ICP Group SA)
• Inventors: Hurray, Paul Gregory, Starr, Cris Damon
• Primary Examiner(s): Scherbel, David A.
• Assistant Examiner(s): Nguyen, Dinh Q.
• Application Number:
  US09/471,994
• Time in Patent Office: 782 Days
• Field of Search: 239/413, 239/414, 239/400, 239/416.1, 239/416.3, 239/42.8, 239/430, 239/432, 239/487, 239/526, 239/527, 239/600, 239/415, 239/112, 239/114, 239/113, 239/115, 239/117, 222/137, 222/145.6, 222/145.5, 222/256, 222/509
• US Class Current: 239/413
• CPC Class Codes: B01F 2101/2305 Mixers of the two-component package type, i.e. where at least two components are separately stored, and are mixed in the moment of application
• CPC Class Codes: B01F 33/5011 portable during use, e.g. hand-held
• CPC Class Codes: B05B 1/3402 to avoid or to reduce turbulencies, e.g. comprising fluid flow straightening means
• CPC Class Codes: B05B 12/0024 to a single position
• CPC Class Codes: B05B 12/0026 to inhibit delivery
• CPC Class Codes: B05C 17/00506 Means for connecting the outlet element to, or for disconnecting it from, the hand tool or its container
• CPC Class Codes: B05C 17/00516 Shape or geometry of the outlet orifice or the outlet element
• CPC Class Codes: B29B 7/7438 Mixing guns, i.e. hand-held mixing units having dispensing means B29B7/761, B29B7/7678 take precedence

Abstract

A two-component dispensing gun has two longitudinally-extending dispensing passages receiving metering rods and in fluid communication with two feed passages adjacent to an especially configured metering rod tip and valve seats formed at the exit end of each dispensing passage. Valve seats of the dispensing passage extend as protrusions from the gun nose and are sealingly received within cup shaped recesses formed in a detachable, throwaway nozzle having a static mixing chamber. The nozzle has a truncated cone configuration which, in combination with the geometric configuration of the dispensing and feed passages alleviates turbulent flow of the liquid components until reaching the static mixer within the nozzle. A cammed surface on each metering rod in combination with a yoke crossbar formed as part of the gun'"'"'s trigger provides increased motion of the trigger for fine or slow metering applications of the gun.

Claims

1. An airless two-component polyurethane foam dispensing gun comprising:

a) a body having a longitudinally-extending valve portion containing a pair of laterally displaced, generally parallel and straight longitudinally-extending tubular dispensing passages without significant bends or angles formed therein, each dispensing passage having a conical valve seat at one end opening to a nose portion of said body and an open end at its opposite end forming a metering rod opening in said body;

said body'"'"'s valve portion having a generally straight feed passage without significant bends or angles formed therein extending along a feed passage axis for each dispensing passage, each feed passage having a discharge end in fluid communication with a dispensing passage closely adjacent said dispensing passage'"'"'s valve seat end and an inlet end defining an opening in said body for receiving one of said two-components of said polyurethane foam;

said feed passage axis forming an acute angle less than about 30°

with said dispensing passage;

b) a longitudinally-extending metering rod in each dispensing passage, each metering rod having a conical valve tip section at one end for sealing and opening said valve seat upon longitudinal movement of said metering rod in said passage, a yoke collar section at its opposite end and an intermediate tubular sealing section for sealing and guiding said metering rod within its respective dispensing passage, said intermediate section extending through said metering rod opening and spaced away from said discharge end of said feed passage throughout said metering rod movement;

c) a nozzle detachably connected in a sealing manner to said nose portion having an outlet tip at one end, an inlet chamber at its opposite end and a static mixing chamber containing a static mixer therebetween;

d) a spring in contact with said yoke collar of each metering rod biasing said valve tip of each metering rod into contact with said valve seat of each dispensing passage; and

,

e) a manually operable trigger to move said metering rods against the bias of said spring to discharge polyurethane components through said valve seats.

2. The dispensing gun of claim 1 wherein said nose portion of said body has a generally flat nose face surface with openings therein defined by said conical valve seat of each dispensing passage;

said nose face surface defined by an edge including a pair of generally semi-circular portions, each semi-circular edge portion generally concentric with a valve seat;

said mixing chamber of said nozzle generally cylindrical with a diameter smaller than the diameter of said nozzle face edge'"'"'s semi-circular portions, said inlet chamber of said nozzle having conically shaped guiding wall portions extending adjacent said semi-circular edge portions to said mixing chamber whereby each component of said foam smoothly flows from its feed passage through its dispensing passage, past its valve seat and along the guiding wall portions until meeting said mixing chamber without abrupt directional changes in flow.

3. The dispensing gun of claim 1 wherein said body further having i) a transversely extending handle portion, ii) a longitudinally-extending, open ended spring portion generally aligned with said dispensing passages and generally transversely adjacent said handle portion, and iii) a longitudinally-extending trigger recess portion between said valve portion and said spring portion;

said open end of said dispensing passages opening to said trigger recess at one end thereof and an inner open end of said spring base portion opening to the opposite end of said trigger recess;

a trigger having a trigger yoke crossbar portion received within said trigger recess and a trigger lever portion transversely extending from said crossbar, said crossbar having a pair of laterally spaced metering rod openings through which said intermediate tubular sealing section of each metering rod extends and a trigger pivot portion transversely extending from said crossbar opposite said trigger lever;

said trigger pivot extending into a generally U-shaped portion of said recess transversely spaced from said metering rods;

said metering rods'"'"' yoke collar section generally cylindrical and larger in diameter than said metering rod openings in said crossbar and extending between a generally flat end surface adjacent said spring base and an annular, radially outward collar surface extending from the intersection of said tubular sealing section with said yoke collar section, said collar surface chamfered at a set angle whereby said trigger when pivoted about trigger pivot also pivots about said collar surface to provide precise metering of said foam components through said dispensing passages.

4. The dispensing gun of claim 3 wherein said handle has at least one groove formed therein opening to face said trigger lever and said trigger lever has a transversely extending trigger lever recess opening to said handle portion formed therein, a lock tab pivotably mounted Within said trigger lever recess and operator actuated from a stored position whereat said lock tab is contained within said trigger lever recess and a locked position whereat said lock tab is pivoted out of said trigger level recess into said at least one groove rendering said dispensing gun inoperable for dispensing said foam components.

5. The dispensing gun of claim 3 further including an inner spring retainer at said inner open end of said spring portion in contact with said flat end surfaces of each metering rod'"'"'s yoke collar sections;

an outer spring retainer at the opposite outer open end of said body'"'"'s spring portion closing said outer open end and a single spring between said inner and outer spring retainers whereby equal spring pressure is constantly exerted on both metering rods in combination with said crossbar to assure equal movement of both metering rods and equal flow of said polyurethane foam components upon rotation of said trigger lever.

6. The dispensing gun of claim 5 wherein said yoke collar section of each metering rod has a tubular recess extending therein from said flat end surface of said base section and said inner retainer has a tubular projection extending therefrom aligned with and received within said tubular recess of each metering rod whereby said metering rods and said spring are longitudinally aligned to assure longitudinal movement of each metering rod within said dispensing passage.

7. The dispensing gun of claim 1 wherein said nose portion has a generally flat nose surface;

said nozzle having a back plate at said nozzle'"'"'s opposite end, said back plate having a generally flat outer surface adjacent said body'"'"'s nose face surface and a pair of cup shaped recesses receiving said protrusions when said nozzle is affixed to said body;

each cup shaped recess having a valve seat extension opening extending through said back plate in registry with said valve seat opening in said protrusions;

said back plate having an inner surface facing said static mixing chamber and forming the inlet of said inlet chamber;

a flexible flapper strip affixed approximately at its mid-point to said back plate'"'"'s inner surface and extending across said cup shaped recess to covering each valve seat extension opening when said polyurethane foam components are not being discharged by said gun.

8. The dispensing gun of claim 7 wherein said nose portion'"'"'s generally flat nose surface is defined in configuration by a nose edge including a pair of generally semi-circular portions, each generally concentric with one of said valve seat protrusions;

said nozzle'"'"'s inlet chamber defined by said back plate and a longitudinally-extending mixing chamber wall, said chamber wall generally cylindrical with diameter smaller than that of said nose edge'"'"'s semi-circular portions at said nose face and conically tapering to said static mixing chamber whereby the flexing of said resilient flapper strip directs the foam components discharged from said valve seat extension openings towards said mixing chamber wall away from each other until contact is made at said static mixing chamber.

9. The dispensing gun of claim 8 wherein said inlet chamber further includes a longitudinally-extending divider wall extending from said static mixer to a position spaced from said resilient flapper.

10. An airless two-component polyurethane foam dispensing gun comprising:

a) a body having a longitudinally-extending valve portion containing a pair of laterally displaced, generally parallel and straight longitudinally-extending tubular dispensing passages without significant bends or angles formed therein, each dispensing passage having a conical valve seat at one end opening to a nose portion of said body and an open end at its opposite end forming a metering rod opening in said body;

said body'"'"'s valve portion having a generally straight feed passage extending along a feed passage axis for each dispensing passage, each feed passage having a discharge end in fluid communication with a dispensing passage adjacent said dispensing passage'"'"'s valve seat end and an inlet end defining an opening in said body for receiving one of said two-components of said polyurethane foam;

said feed passage axis forming an acute angle less than about 30°

with said dispensing passage;

b) a longitudinally-extending metering rod in each dispensing passage, said metering rod having a conical valve tip section at one end, a yoke collar section at its opposite end and an intermediate tubular sealing section for sealing and guiding said metering rod within said dispensing passage, said intermediate section extending through said metering rod opening;

c) a nozzle detachably connected in a sealing manner to said nose portion having an outlet tip at one end, an inlet chamber at its opposite end and a static mixing chamber containing a static mixer therebetween;

d) a spring in contact with said yoke collar of each metering rod biasing said valve tip of each metering rod into contact with said valve seat of each dispensing passage;

e) a manually operable trigger to move said metering rods against the bias of said spring;

f) said nose portion of said body has a generally flat nose face surface with openings therein defined by said conical valve seat of each dispensing passage;

said nose face surface defined by an edge including a pair of generally semi-circular portions, each semi-circular edge portion generally concentric with a valve seat;

said mixing chamber of said nozzle generally cylindrical with a diameter smaller than the diameter of said nozzle face edge'"'"'s semi-circular portions, said inlet chamber of said nozzle having conically shaped guiding wall portions extending adjacent said semi-circular edge portions to said mixing chamber whereby each component of said foam smoothly flows from its feed passage through its dispensing passage, past its valve seat and along the guiding wall portions until meeting said mixing chamber without abrupt directional changes in flow; and

,

said valve seat of each dispensing passage is formed in part by a valve seat protrusion extending beyond said nose face surface;

said nozzle having a back plate at said nozzle'"'"'s opposite end, said back plate having a generally flat outer surface adjacent said body'"'"'s nose face surface and a pair of cup shaped recess receiving said protrusions when said nozzle is affixed to said body;

each cup shaped recess having a valve seat extension opening extending through said back plate in registry with said valve seat opening in said protrusions, each protrusion ending in a generally flat protrusion seating surface and each recess having a generally circular sealing lip extending from the base of said cup shaped recess whereby sealing of said nozzle with said gun body occurs by deformation of said sealing lip and/or said protrusion seating surface when said nozzle is attached to said gun body.

11. The dispensing gun of claim 10 wherein said conical valve tip of each metering rod has at its end a generally cylindrical tip portion, a truncated conical portion adjacent said cylindrical tip portion and extending therefrom and a larger cylindrical body portion extending from said conical portion to said intermediate tubular sealing section, said cylindrical tip extending past said sealing lip and into said valve seat extension opening of said back plate when said nozzle is attached to said gun body and said gun is not actuated whereby upon gun actuation fine metering of said two-components is possible as well as adjustable flow metering throughout the full range of trigger actuation.

12. The dispensing gun of claim 11 wherein said conical valve seat has a minor diameter at said valve seat opening in said valve seat protrusion and said valve seat extension opening has a diameter less than the diameter of said minor diameter of said valve seat opening whereby generally constant fine metering occurs until said cylindrical tip portion leaves said valve seal extension opening upon rearward retraction of said metering rod.

13. The dispensing gun of claim 11 wherein said conical valve seat is a frusto-conical surface having a minor diameter at the opening of said dispensing passage, said truncated conical portion of said metering rod within said frusto-conical surface throughout the range of trigger actuation of said gun;

the annulus between said cylindrical tip portion of said metering rod and said valve seat'"'"'s frusto-conical surface having less area than the area of said minor diameter of said frusto-conical surface throughout the travel of said metering rod from its initial to its full opening position whereby variable metering of the components of said dispensing gun occurs.

14. The dispensing gun of claim 11 wherein said nose portion of said gun body has a lip longitudinally-extending from said nose edge, said nozzle within said lip when attached to said gun body;

said nose lip having an upper flat and lower flat between semi-circular ends extending from said semi-circular portions of said nose edge;

said lower flat having a groove formed therein;

said upper flat having a snap ledge longitudinally-extending in a direction opposite said lip;

said nozzle having a seating ledge extending from the bottom thereof to fit within said groove when said nozzle is applied to said gun body and a latch extending from the top thereof adapted to snap over and seat against snap ledge when said nozzle is applied to said gun body whereby sealing by said sealing lip between said nozzle and said body occurs.

15. An airless two-component polyurethane foam dispensing gun comprising:

a) a body having a longitudinally-extending valve portion containing a pair of laterally displaced, generally parallel and straight longitudinally-extending tubular dispensing passages without significant bends or angles formed therein, each dispensing passage having a conical valve seat at one end opening to a nose portion of said body and an open end at its opposite end forming a metering rod opening in said body;

said body'"'"'s valve portion having a generally straight feed passage extending along a feed passage axis for each dispensing passage, each feed passage having a discharge end in fluid communication with a dispensing passage adjacent said dispensing passage'"'"'s valve seat end and an inlet end defining an opening in said body for receiving one of said two-components of said polyurethane foam;

said feed passage axis forming an acute angle less than about 30°

with said dispensing passage;

b) a longitudinally-extending metering rod in each dispensing passage, said metering rod having a conical valve tip section at one end, a yoke collar section at its opposite end and an intermediate tubular sealing section for sealing and guiding said metering rod within said dispensing passage, said intermediate section extending through said metering rod opening;

c) a nozzle detachably connected in a sealing manner to said nose portion having an outlet tip at one end, an inlet chamber at its opposite end and a static mixing chamber containing a static mixer therebetween;

d) a spring in contact with said yoke collar of each metering rod biasing said valve tip of each metering rod into contact with said valve seat of each dispensing passage;

e) a manually operable trigger to move said metering rods against the bias of said spring;

f) said body further having i) a transversely extending handle portion, ii) a longitudinally-extending, open ended spring portion generally aligned with said dispensing passages and generally transversely adjacent said handle portion, and iii) a longitudinally-extending trigger recess portion between said valve portion and said spring portion;

said open end of said dispensing passages opening to said trigger recess at one end thereof and an inner open end of said spring base portion opening to the opposite end of said trigger recess;

g) a trigger having a trigger yoke crossbar portion received within said trigger recess and a trigger lever portion transversely extending from said crossbar, said crossbar having a pair of laterally spaced metering rod openings through which said intermediate tubular sealing section of each metering rod extends and a trigger pivot portion transversely extending from said crossbar opposite said trigger lever;

said trigger pivot extending into a generally U-shaped portion of said recess transversely spaced from said metering rods;

h) said metering rods'"'"' yoke collar section generally cylindrical and larger in diameter than said metering rod openings in said crossbar and extending between a generally flat end surface adjacent said spring base and an annular, radially outward collar surface extending from the intersection of said tubular sealing section with said yoke collar section, said collar surface chamfered at a set angle whereby said trigger when pivoted about trigger pivot also pivots about said collar surface to provide precise metering of said foam components through said dispensing passages;

said handle has at least one groove formed therein opening to face said trigger lever and said trigger lever has a transversely extending trigger lever recess opening to said handle portion formed therein, a lock tab pivotably mounted within said trigger lever recess and operator actuated from a stored position whereat said lock tab is contained within said trigger lever recess and a locked position whereat said lock tab is pivoted out of said trigger level recess into said at least one groove rendering said dispensing gun inoperable for dispensing said foam components; and

,

said handle has a plurality of grooves opening to said trigger lever transversely spaced at set distances on said handle between said at least one groove to a position adjacent to but spaced from said spring base;

said lock tab pivotably movable out of said trigger recess to positions aligned with any one of said handle grooves whereby predetermined metering of said polyurethane components in combination with a positive gun stop occurs.

16. An airless, two-component dispensing gun comprising:

a) a body having a longitudinally-extending valve portion containing a pair of laterally displaced, generally parallel, longitudinally-extending, tubular dispensing passages and a feed passage intersecting each dispensing passage;

each dispensing passage having a conical valve seat adjacent one of its ends formed as a protrusion extending from a generally flat nose surface at one end of said body and the opposite end of each dispensing passage forming a metering rod opening in said body'"'"'s valve portion;

b) a longitudinally-extending metering rod in each dispensing passage, said metering rod at one end having a conical valve tip end section including a generally cylindrical tip portion ending in a frusto-conical portion, in turn, ending in a larger cylindrical portion;

an intermediate tubular sealing section adjacent said larger cylindrical portion extending through said metering opening in said dispensing passage and a yoke collar section at its opposite end adjacent said intermediate tubular section;

c) a nozzle detachably connected to said nose surface and having a pair of cup shaped recesses sealingly receiving said valve seat protrusions, each recess having at its base a valve sat extension opening in registry with said valve seat extension opening in said dispensing passage and opening to an inlet chamber within said nozzle, each metering rod'"'"'s tip portion extending within said extension opening when said gun is not actuated;

d) a trigger i) having a yoke crossbar portion with a pair of metering rod openings through which said intermediate section of said metering rods extend, ii) a trigger lever portion extending transversely from one side of said crossbar and iii) a trigger pivot portion extending from the opposite of said crossbar received within a U-shaped recess within said body; and

,

e) a spring in contact with an end face surface of said collar yoke section of each metering rod;

said yoke collar section having an annular, collar surface extending radially outward at the intersection of said metering rod'"'"'s intermediate section with said yoke collar section, said collar surface bearing against said trigger'"'"'s crossbar and chamfered at a set angle to produce a cam pivot providing increased rotational movement of said trigger lever about said trigger pivot which in combination with said metering rod'"'"'s tip portion and said valve seat extension opening permits fine metering of the components.

17. The dispensing gun of claim 16 wherein said feed passage is in fluid communication with said dispensing passage at a position adjacent said valve seat in said dispensing passage, said feed passage generally straight and intersecting the longitudinal axis of said dispensing passage at an angle of no more than about 30°

whereby turbulent flow of said components through Said dispensing passage is avoided.

18. The dispensing gun of claim 16 wherein said body has a handle portion transversely extending therefrom adjacent said trigger lever and said handle portion has at least one groove formed therein opening to face said trigger lever;

said trigger lever portion has a transversely extending trigger lever recess opening to said handle portion formed therein;

a lock tab pivotably mounted within said trigger lever recess and operator actuated from a stored position whereat said lock tab in contained within said trigger lever recess and a locked position whereat said lock tab is pivoted out of said trigger level recess into said at least one groove rendering said dispensing gun inoperable for dispensing said foam components.

19. The dispensing gun of claim 18 wherein said handle has a plurality of grooves opening to said trigger lever transversely spaced at set distances on said handle between said at least one groove to a position adjacent to but spaced from said spring base;

said lock tab pivotably movable out of said trigger recess to positions aligned with any one of said handle grooves whereby slow metering of said polyurethane components in combination with a positive gun stop occurs.