Dispensing gun with valving rod and bellows-type seal

• US 5,887,756 A
• Filed: 03/31/1997
• Issued: 03/30/1999
• Est. Priority Date: 06/23/1994
• Status: Expired due to Term

• Current Assignee: Insta-Foam Products Incorporated
• Original Assignee: Insta-Foam Products Incorporated
• Inventors: Brown, Daniel P.
• Primary Examiner(s): Kaufman, Joseph A.
• Application Number:
  US08/828,667
• Time in Patent Office: 729 Days
• Field of Search: 222/135, 222/136, 222/137, 222/145.1, 222/145.5, 222/145.7, 222/287, 222/394, 222/509, 222/510, 222/518
• US Class Current: 222/136
• CPC Class Codes: B05B 1/3046 the valve element, e.g. a needle, co-operating with a valve seat located downstream of the valve element and its actuating means, generally in the proximity of the outlet orifice B05B1/308 takes precedence
• CPC Class Codes: B05B 12/002 Manually-actuated controlling means, e.g. push buttons, levers or triggers for single units B05B11/00
• CPC Class Codes: B05B 12/0022 associated with means for restricting their movement
• CPC Class Codes: B05B 9/0894 Gun with a container which, in normal use, is located above the gun
• CPC Class Codes: B29B 7/7409 with supply of gas
• CPC Class Codes: B65D 83/202 combined with a hand grip hand-held or body-worn self-defense devices using aerosol containers F41H9/10
• CPC Class Codes: B65D 83/207 Actuators comprising a manually operated valve and being attachable to the aerosol container, e.g. downstream a valve fitted to the container; Actuators associated to container valves with valve seats located outside the aerosol container portable spraying apparatus comprising pressurised supply containers B05B7/2402, B05B9/0805; manually actuated controlling means for spraying apparatus B05B12/002; actuators connected to the aerosol container by a flexible tube B65D83/756
• CPC Class Codes: B65D 83/303 using extension tubes located in or at the outlet duct of the nozzle assembly

Abstract

A dispensing gun for fluent products such as viscous adhesives and sealants. The gun includes a removably mounted nozzle and fittings for attachment to a product source such as a can or a hose. A valve body has product inlet and outlet passages with flow being controlled therethrough by a valve that includes a nose portion seated in the valve body, and a rod that extends through the nose portion of the valve and seats on tapered surfaces inside the end of the nozzle. The valve contains a shrouded internal spring biasing the valve to a closed position. A trigger engages the yoke carrying the valve and the valving rod and moves the yoke so that the rod and valve move between open, closed and intermediate positions. In one preferred form, the valving rod may be adjusted between positions wherein more or less product is dispensed in response to full trigger movement.

Claims

1. An improved dispensing gun for fluent products, said dispensing gun comprising, in combination, a gun body portion, a handle, a trigger unit and a dispensing nozzle having an inlet, an outlet and an elongated center passage, said gun body having a product inlet passage, a product outlet passage, and a formation for liquid-tight attachment to a source of said fluent products, said product outlet passage communicating with said nozzle inlet, a reciprocable metering assembly including a valving rod passing through at least a portion of said gun body, a seal assembly having a portion secured to a part of said gun body and a portion secured to and reciprocable with said valving rod, a portion of said reciprocable metering assembly having surfaces dimensioned and shaped for fluidtight contact with annular surfaces forming a valve seat in at least one of said outlet passage and said dispensing nozzle, a resilient, force-applying element urging said metering assembly to a liquid-tight, closed position, said valving rod having a rear end portion, a center portion and a forward end portion, an operative connection between a portion of said metering assembly and said trigger, said seal assembly including a hollow body in the form of a bellows, said bellows being disposed between said portions of said seal secured respectively to said part of said gun body and said valving rod, said bellows being substantially radially incompressible under forces created by aid fluent product but axially expansible and contractible throughout a free but limited range of rod movement when said rod is reciprocated by said trigger.

2. A dispensing gun as defined in claim 1 wherein said valve seat is formed on an inner surface of said dispensing nozzle adjacent said outlet thereof.

3. A dispensing gun as defined in claim 1 wherein said bellows is made from a metal material.

4. A dispensing gun as defined in claim 3 wherein said metal material is stainless steel.

5. A dispensing gun as defined in claim 1 wherein said valve seat is formed adjacent said inlet on said dispensing nozzle.

6. A dispensing gun as defined in claim 1 wherein said reciprocable metering assembly includes a valve head carried by said center portion of said valving rod.

7. A dispensing gun as defined in claim 1 wherein said gun body includes a separately formed metal center body portion, said product inlet passage, said product outlet passage and said formation for liquid-tight attachment in said gun body comprising tapped openings formed in said center body portion.

8. A dispensing gun as defined in claim 1 wherein said force-applying element comprises a coil spring.

9. A dispensing gun as defined in claim 1 wherein said gun body further includes a spring and a combination spring carrier and guide element, wherein said metering assembly includes a rod actuator affixed to one end of said valving rod, said rod actuator having an elongated cylindrical guide body, wherein said trigger includes claws engaging a portion of said actuator and wherein said actuator further includes an enlarged head portion engaged by said spring, said spring being disposed within said carrier and guide, said carrier and guide having a cylindrical opening therein separated from said actuator guide body by only a working clearance.

10. A dispensing gun as defined in claim 9 which further includes a spring compressor axially adjustably positionable in relation to said spring carrier and guide element.

11. A dispensing gun as defined in claim 1 wherein said formation comprises an attachment for a product supply hose.

12. A dispensing gun as defined in claim 1 wherein said formation comprises a fitting for attachment of a pressurized can.

13. A dispensing gun as defined in claim 1 wherein said product inlet passage includes a anti-backflow check valve disposed therein.

14. In a dispensing gun for fluent products having a gun body, a dispensing nozzle, a trigger and a valving rod having a portion engaging a valve seat portion of said nozzle to form a product dispensing valve, the improvement comprising a seal assembly including an elongated hollow center body portion formed into a bellows configuration, from a plurality of dished elements, a nose portion affixed to one end of said bellows in fluid-tight relation, said nose portion having interior threads formed therein, and a mounting flange affixed to the other end of said bellows in liquid-tight relation, said mounting flange being positionable in snug, fluid-tight relation within a portion of said gun body by a locking element, said bellows, said flange and said nose portion all having openings extending therethrough for reception of said valving rod.