Spray gun for expelling a fluid

• US 20130153684A1
• Filed: 08/25/2011
• Published: 06/20/2013
• Est. Priority Date: 08/25/2010
• Status: Abandoned Application

• Current Assignee: BASF SE
• Original Assignee: BASF SE
• Inventors: Taranta, Claude, Niesar, Gunter, Nolte, Marc, Henkes, Steffen, Huber, Robert, Welter, Peter, Montero, Antonio Zarco, Torres Morato, Jose Antonio
• Application Number:
  US13/818,244
• Publication Number:
  US 20130153684A1
• Time in Patent Office: Days
• US Class Current: 239/337
• CPC Class Codes: B05B 12/008 integrated in or attached to a discharge apparatus, e.g. a spray gun
• CPC Class Codes: B05B 12/08 responsive to condition of liquid or other fluent material to be discharged, of ambient medium or of target ; responsive to condition of spray devices or of supply means, e.g. pipes, pumps or their drive means
• CPC Class Codes: B05B 9/0409 the pumps being driven by a hydraulic or a pneumatic fluid
• CPC Class Codes: F04B 2201/0201 Position of the piston
• CPC Class Codes: F04B 2203/10 of linear elastic fluid motors
• CPC Class Codes: F04B 9/12 the fluid being elastic, e.g. steam or air
• CPC Class Codes: F04B 9/127 rectilinear movement of the pumping member in the working direction being obtained by a single-acting elastic-fluid motor, e.g. actuated in the other direction by gravity or a spring
• CPC Class Codes: F04B 9/14 Pumps characterised by muscle-power operation hand-held spraying or dispensing apparatus using pumps or bulbs B05B11/00

Abstract

The present invention relates to a spray gun for the expulsion of a fluid, with at least one cylinder (1) in which a piston (2) is mounted movably, the cylinder (1) having formed in it a fluid chamber (3), the volume of which can be varied by means of a movement of the piston (2) and in which at least one first cylinder orifice (5) is formed, and a spray orifice which is connected to the first cylinder orifice (5) of the cylinder (1) via a connecting line (20), so that a fluid, which is received by the fluid chamber (3) and is pressed out through the first cylinder orifice (5) by the pressure exerted by the piston (2), arrives via the connecting line (20) at the spray orifice and is expelled there. The spray gun according to the invention is distinguished by the fact that a fluid valve (21) is arranged in the connecting line (20), and, in the cylinder (1) a sensor (29) is provided, by means of which a defined position of the piston (2), in which fluid is still located in the fluid chamber (3) during the expulsion operation, can be detected, and by means of which the fluid valve (21) can be actuated, the fluid valve (21) being closed by means of the sensor (29) when the defined position of the piston (2) has been detected. The invention relates, furthermore, to the use of such a spray gun for the expulsion of plant protectants.

Claims

1-15. -15. (canceled)

16. A spray gun for the expulsion of a fluid, with

at least one cylinder (1) in which a piston (2) is mounted movably, the cylinder (1) having formed in it a fluid chamber (3), the volume of which can be varied by means of a movement of the piston (2) and in which at least one first cylinder orifice (5) is formed, and

a spray orifice which is connected to the first cylinder orifice (5) of the cylinder (1) via a connecting line (20), so that a fluid, which is received by the fluid chamber (3) and is pressed out through the first cylinder orifice (5) by means of the pressure exerted by the piston (2), arrives via the connecting line (20) at the spray orifice and is expelled there,

wherein

a fluid valve (21) is arranged in the connecting line (20), and

in the cylinder (1) a sensor (29) is provided, by means of which a defined position of the piston (2), in which fluid is still located in the fluid chamber (3) during the expulsion operation, can be detected, and by means of which the fluid valve (21) can be actuated, the fluid valve (21) being closed by means of the sensor (29) when the defined position of the piston (2) has been detected.

17. The spray gun according to claim 16,

wherein

the defined position of the piston (2) is detected by the sensor (29) by means of a magnetic field generated or varied by the piston (2).

18. The spray gun according to claim 16,

wherein,

the cylinder (3) forms in it a pressure chamber (4), in which is formed at least one second cylinder orifice (6) which is connected to a first connection (7) for a compressed gas line (8).

19. The spray gun according to claim 16,

wherein

the spray gun has a second connection (32) for a fluid reservoir (24), which connection is connected to the first cylinder orifice (5) and via which fluid can be conveyed into the fluid chamber (3).

20. The spray gun according to claim 16,

wherein

the fluid valve (21) is a first 3/2-way valve, in which, in a first setting, a passage of fluid from the first cylinder orifice (5) to the spray orifice is provided, and, in a second setting, a passage of fluid from the second connection (32) to the first cylinder orifice (5) is provided.

21. The spray gun according to claim 18,

wherein

between the first connection (7) and the second cylinder orifice (6), a compressed gas valve (17) designed as a second 3/2-way valve is arranged, in which, in a first setting, a passage of compressed gas from the first connection (7) to the second cylinder orifice (6) is provided, and, in a second setting, a passage of compressed gas from the second cylinder orifice (6) into the open is provided.

22. The spray gun according to claim 21,

wherein

the sensor (29) is coupled to the first and the second 3/2-way valve, and the sensor (29) switches the first and the second 3/2-way valve into the second setting when the piston (2) is in the defined position, so that the expulsion of fluid through the spray orifice is interrupted and fluid is conveyed by means of the compressed gas from the fluid reservoir (24) into the fluid chamber (3) via the first 3/2-way valve (21).

23. The spray gun according to claim 21,

wherein

the spray gun has a trigger (31) which is coupled to the first and the second 3/2-way valve and which, when actuated, switches the first and the second 3/2-way valve into the first setting, so that the piston (2) is moved by the compressed gas in the pressure chamber (4), such that the volume of the fluid chamber (3) is reduced and fluid is expelled through the spray orifice.

24. The spray gun according to claim 16,

wherein

the spray gun has a regulating device (14, 15), by means of which the movement of the piston (2) in the cylinder (1) and, consequently, the maximum volume of the fluid chamber (3) can be limited.

25. The spray gun according to claim 16

wherein

a first and a second fluid chamber (3, 34) are formed in the cylinder (1), and at least the first cylinder orifice (5) is formed in the first fluid chamber (3) and at least one second cylinder orifice (6) is formed in the second fluid chamber (34),

the fluid received by the first fluid chamber (3) can be pressed out by fluid being pressed under pressure into the second fluid chamber (34), with the result that force is exerted upon the piston (2) in the direction of a reduction in the size of the first fluid chamber (3), and

the fluid received by the second fluid chamber (34) can be pressed out by fluid being pressed under pressure into the first fluid chamber (3), with the result that force is exerted upon the piston (2) in the direction of a reduction in the size of the second fluid chamber (34).

26. The spray gun according to claim 16,

wherein

the spray gun comprises a first and a second cylinder (1-1, 1-2),

in that a first fluid chamber (3-1) with a first cylinder orifice (5-1) is formed in the first cylinder (1-1) and a second fluid chamber (3-2) with a second cylinder orifice (5-2) is formed in the second cylinder (1-2),

in that a first pressure chamber (4-1) is formed in the first cylinder (1-1) and a second pressure chamber (4-2) is formed in the second cylinder (1-2), the first and the second pressure chamber (4-1, 4-2) communicating with one another and comprising a non-compressible working fluid,

the first fluid chamber (3-1) is separated from the first pressure chamber (4-1) by a first piston (2-1), and the second fluid chamber (3-2) is separated from the second pressure chamber (4-2) by a second piston (2-2), the volume of the first fluid chamber (4-1) decreasing when the volume of the second fluid chamber (4-2) increases,

the fluid received by the first fluid chamber (3-1) can be pressed out by fluid being pressed under pressure into the second fluid chamber (3-2), with the result that force is exerted upon the second piston (2-2) and is transmitted to the first piston (2-1) via the working fluid, and

the fluid received by the second fluid chamber (3-2) can be pressed out by fluid being pressed under pressure into the first fluid chamber (3-1), with the result that force is exerted upon the first piston (2-1) and is transmitted to the second piston (2-2) via the working fluid.

27. The spray gun according to claim 16,

wherein

the fluid is a liquid, and the spray orifice is surrounded by a spray nozzle (22) which, when the liquid passes through it, generates a liquid jet (23).