US3819115A - Electrostatic spray gun - Google Patents

Electrostatic spray gun Download PDF

Info

Publication number
US3819115A
US3819115A US00340549A US34054973A US3819115A US 3819115 A US3819115 A US 3819115A US 00340549 A US00340549 A US 00340549A US 34054973 A US34054973 A US 34054973A US 3819115 A US3819115 A US 3819115A
Authority
US
United States
Prior art keywords
duct
powder
electrode
spray gun
annular
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00340549A
Other languages
English (en)
Inventor
C Soderman
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Atlas Copco AB
Original Assignee
Atlas Copco AB
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Atlas Copco AB filed Critical Atlas Copco AB
Application granted granted Critical
Publication of US3819115A publication Critical patent/US3819115A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
    • B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
    • B05B5/00—Electrostatic spraying apparatus; Spraying apparatus with means for charging the spray electrically; Apparatus for spraying liquids or other fluent materials by other electric means
    • B05B5/025—Discharge apparatus, e.g. electrostatic spray guns
    • B05B5/03—Discharge apparatus, e.g. electrostatic spray guns characterised by the use of gas, e.g. electrostatically assisted pneumatic spraying
    • B05B5/032—Discharge apparatus, e.g. electrostatic spray guns characterised by the use of gas, e.g. electrostatically assisted pneumatic spraying for spraying particulate materials

Definitions

  • the duct is annular and the electrode has an annular forward-directed edge that has a clearance to UNITED STATES PATENTS the walls of the duct and is located at a touch protectgrastznin.i i i distance from the mouth of the duct Oll'l e a 3,688,990 9/1972 Liedberg 239/15 X 17 Claims, 9 Drawing Figures PAliNlEnJuuzslsn SHEEI 1 OF 2 OM m W W4 WM RMWWOW .UWM4 1 1 v PATENTEDJUNZSIHH 1819.115
  • This invention relates to a powder spray gun having a powder emitting duct, formed of an electrically insulating material, to which the powder is carried as a gas suspension, and an electrode for electrostatically charging.
  • the electrods is usually situated at the end of the mouth of the duct or outside the mouth.
  • an external electrode By reason of safety, it is not desirable to have an external electrode and attempts have been made to utilize needle electrodes inside the duct. However, such electrodes have proved not to give as good an electrostatic charge to the powder as external electrodes do.
  • FIG. 1 is a longitudinal section through a handheld powder spray gun according to the invention
  • FIGS. 2 and 3 are cross sections along lines 22 and 33, respectively, in FIG. 1;
  • FIGS. 4, 6 and 8 are fragmentary longitudinal sections through modified forms of the forward nozzleforming portion of the powder spray gun
  • FIGS. 5, 7 and 9 are front views seen as indicated by the arrows 5, 7-7 and 9-9 in FIGS. 4, 6 and 8, respectively.
  • the spray gun shownin FIGS. 1-3 comprises a rear metal member 11 mainly comprising a handle, a barrel 12 and a forwardmember 13.
  • the two members 12, 13 are made of an electrically insulating material, for instance a plastic, and they form an axial duct 14 to which a hose 15 is connected.
  • the duct 14 is supplied with a suspension of paint powder in air or another gas from a non-illustrated suitable source, for instance from an apparatus which provides a fluidized bed of powder.
  • a deflector device 16 comprises a central and axial tube-like member 17 which by means of two spokes 18 is connected to a ring 19 that abuts a shoulder 20 in the duct 14.
  • the deflector device 16 is also shown in FIG. 4.
  • the ring 19 is held in place by means of an annular metallic electrode 21 which in turn is held in place by means of the forward plastic member 13 which is threaded onto the barrel 12.
  • the rear end of the tubelike member 17 is guided by means of a number of vane-like spokes 22 and the tube-like member 17 forms an inner wall of the duct 14, i.e., it makes the duct annular.
  • a deflector head 23 has a spindle 24 which is screwed into the rear end of the tube-like member 17,
  • an annular passage 25 is formed between the spindle 24 and the tube-like member 17.
  • Passages 26,27 in the spokes 18 end in this passage 25.
  • the entire deflector device 16, i.e., also the deflector head 23 and its spindle 24, should be electrically insulating, for instance by being made of a plastic material.
  • the passages 26,27 in the spokes 18 are connected to a passage 28 in the housing and this passage 28 leads via a control 6 valve 29 in the rear member 11 of the housing to an air valve 30 operated by a trigger 31.
  • the air valve 30 is supplied with compressed air from a non-illustrated hose connected to a fitting 32.
  • a control passage 33 leads from the passage 28 through a control hose 34 to the powder supplying apparatus previously mentioned but not illustrated.
  • the electrode 21 has a forward-directed annular portion 35 ending in an edge 35a, and it is connected to an insulated electric cable 36 through a protecting impedance 37.
  • the cable 36 is connected to one of the poles of a high voltage source 38 which has its other pole grounded.
  • the handle portion 11 is electrically conducting and grounded through a braided metallic shield of the cable 36.
  • the air valve 30 When the trigger 31 is actuated, the air valve 30 is opened so that there will be an air stream through the passage 28 and the passages 26,27,25 to the deflector head 23.Simultaneously the control passage 33 is pressurized which on the one hand actuates a nonillustrated switch to start the high voltage source 38 and on the other hand initiates the supply of the powder-air mixture through the hose 15.
  • FIGS. 4-5, 6-7 and 8-9 Three modified electrodes are shown in the FIGS. 4-5, 6-7 and 8-9, respectively.
  • the deflector device 16 shown in FIG. 1 is shown in FIGS. 4 and 5 but it is not shown in FIGS. 6-9.
  • it should be used also in connection with the modified electrodes in FIGS. 6-9 because it improves the touch protection of the electrodes. It has also a positive influence on the charging of the powder and it forms the jet into a powder cloud in response to the adjustment of the control valve 29.
  • the ring 35 is attached to an outer ring 41 by means of four spokes 40, and the outer ring 41 is secured in the duct 14.
  • the electrode shown in FIGS. 8 and 9 has not a continuous edge butit has a great number of forwardly directed needles 42 which form an annular edge portion 43 with their tips.
  • a powder spray gun having: an annular powder emitting duct having a mouth at the forward end thereof for emitting said powder, the outer and inner walls of which are formed of an electrically insulating material, to which duct the powder is to be carried suspended in a gas, and
  • an electrode connectable to a source of high voltage said electrode comprising an annular base secured to the outer wall of the duct and means extending from said annular base and forming an annular forwardly directed edge portion which has a radial clearance to the walls of the duct and is recessed in said duct at a touch-protecting distance from the mouth of the duct, said forwardly directed edge portion being the foremost extending portion of the electrode in the duct.
  • a powder spray gun as defined in claim 1 including means located rearwardly of said electrode for imparting a twisting motion to the powder suspension transmitted through the duct.
  • a powder spray gun as defined in claim 1 in which said electrode is axially clamped between a rear body and a forward body which form together the outer wall of said duct.
  • a powder spray gun as defined in claim 5 in which said forward and rear bodies are screwed together.
  • a powder spray gun as defined in claim 5 in which an elongated central body, forming the inner wall of the duct, has a mount which is axially clamped, together with said annular base of the electrode, between said rear and forward bodies forming the outer wall of the duct.
  • a powder spray gun as defined in claim 7 in which said elongated body at its rear end has radial fins for imparting a twisting motion to the powder suspension transmitted through the duct.
  • a powder spray gun as defined in claim 7 in which said elongated body carries a deflector disposed outside of the mouth of the duct.
  • a powder spray gun as defined in claim 5 in which a lead connected to high voltage is located in an axial passage in said rear body and abuts axially against the electrode to apply high voltage thereto.
  • a powder spray gun comprising:
  • a front and a rear member made of an electrically insulating material and forming a wall of a powder emitting duct, the rear end of said duct being adapted to receive a flow of powder entrained in air
  • said electrode having a forwardly directed extension comprised of a plurality of forwardly directed needle-shaped elements in said duct, said forwardly directed extension having a clearance to the wall of the duct, and
  • a lead for high voltage located in an axial passage in said rear member and abutting axially against the electrode to apply high voltage thereto.
  • a powder spray gun comprising:
  • a cap of electrically insulating material removably attached to said barrel, said cap having a duct forming an extension of said axial duct in the barrel and forming a powder emitting mouth,
  • annular electrode connectable to a source of high voltage and having a forwardly directed edge portion which has a radial clearance to the duct of said cap and is recessed in said duct at a touch protecting distance from said mouth, said forwardly directed edge portion being the foremost extending portion of the electrode in the duct, and r a device upstream of said electrode to impart a twisting motion to the powder-gas suspension transmitted through the duct, said device and said electrode being fastened in the duct by being axially clamped between said barrel and said cap.
  • a powder spray gun as defined in claim 12 in which said device is formed of electrically insulating material and comprises a body coaxially located in the d tan l carried by spokes, said body extendirg for wardly through said electroieandsafi riouth, a gas passage leading through one of said spokes and through said central body to provide for a deflecting gas flow substantially transverse to the flow of powder and gas emitted from said mouth, said gas passage being connected to a gas supply passage in said barrel.
  • a powder spray gun having:
  • annular duct defined by an outer and an inner wall of electrically insulating material, said duct forming a powder emitting mouth and being adapted to be supplied with a flow of powder suspended in a carrier gas

Landscapes

  • Electrostatic Spraying Apparatus (AREA)
US00340549A 1972-03-13 1973-03-12 Electrostatic spray gun Expired - Lifetime US3819115A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
SE7203197A SE371942B (enrdf_load_stackoverflow) 1972-03-13 1972-03-13

Publications (1)

Publication Number Publication Date
US3819115A true US3819115A (en) 1974-06-25

Family

ID=20261589

Family Applications (1)

Application Number Title Priority Date Filing Date
US00340549A Expired - Lifetime US3819115A (en) 1972-03-13 1973-03-12 Electrostatic spray gun

Country Status (5)

Country Link
US (1) US3819115A (enrdf_load_stackoverflow)
BE (1) BE812038A (enrdf_load_stackoverflow)
DE (1) DE2312363A1 (enrdf_load_stackoverflow)
GB (1) GB1388787A (enrdf_load_stackoverflow)
SE (1) SE371942B (enrdf_load_stackoverflow)

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3892357A (en) * 1974-04-30 1975-07-01 Nordson Corp Electrostatic spray apparatus and method
US4380320A (en) * 1981-02-25 1983-04-19 Nordson Corporation Electrostatic powder spray gun nozzle
US4659019A (en) * 1984-05-30 1987-04-21 Ransburg-Gema Ag Spray device for coating articles with powder
US4660772A (en) * 1984-09-26 1987-04-28 A. O. Smith Corporation Electrostatic powder spray gun nozzle
US4735360A (en) * 1983-04-07 1988-04-05 Kopperschmidt-Mueller Gmbh & Co. Kg Method and apparatus for electrostatic spray powder coating
US4784331A (en) * 1987-05-27 1988-11-15 Nordson Corporation Electrostatic spray gun device and cable assembly
US4798338A (en) * 1984-02-08 1989-01-17 Veb Infrarot-Anlagen Oranienburg Apparatus for the electro-kinetic charging of powdered materials
US4798340A (en) * 1986-01-14 1989-01-17 Esb Elektrostatische Spruh- Und Beschichtungsanlagen G.F. Vohringer Gmbh Electrostatic device for powder spraying with triboelectric powder charging
US4811898A (en) * 1987-09-21 1989-03-14 Nordson Corporation Electrostatic powder spray gun with adjustable deflector and electrostatic shield
US5351903A (en) * 1993-04-06 1994-10-04 Russell Mazakas Electrostatic powder paint gun with trigger control variable voltage
USD397421S (en) 1995-10-31 1998-08-25 Wagner International Ag Powder spray gun
USD441833S1 (en) 1998-11-26 2001-05-08 Itw Gema Ag Spray coating device
US20110095054A1 (en) * 2009-10-22 2011-04-28 Graham Hughes Plunger
USD673020S1 (en) * 2010-12-23 2012-12-25 P.C. Cox Limited Single Trigger dispensers for cartridges
US8528793B2 (en) 2010-12-23 2013-09-10 P. C. Cox Limited Actuator
US8607824B2 (en) 2010-12-23 2013-12-17 P.C. Cox Limited Valve and dispenser using the valve
US8616415B2 (en) 2010-12-23 2013-12-31 P.C. Cox Limited Dispenser
US8870093B2 (en) 2010-12-23 2014-10-28 P.C. Cox Limited Dispenser
US20180369878A1 (en) * 2017-06-26 2018-12-27 Citic Dicastal Co., Ltd Automatic powder cleaning system for mixed-line hub bolt holes and combined powder cleaning gun

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1544697A (en) 1976-10-08 1979-04-25 Coal Ind Spray head
DE3608426C3 (de) * 1986-03-13 1994-11-24 Gema Volstatic Ag Elektrostatische Sprüheinrichtung für Beschichtungspulver
DE3608415A1 (de) * 1986-03-13 1987-09-24 Gema Ransburg Ag Elektrostatische sprueheinrichtung fuer beschichtungspulver
GB8721481D0 (en) * 1987-09-11 1987-10-21 Volstatic Ltd Powder delivery apparatus
KR0184124B1 (ko) * 1996-04-16 1999-03-20 손욱 다중대전 현상건

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3248606A (en) * 1961-12-08 1966-04-26 Sames Mach Electrostat Apparatus for dispersing and electrically charging substances in discrete particulate form
US3263127A (en) * 1961-04-14 1966-07-26 Sames Mach Electrostat Means for electrostatic coating
US3688990A (en) * 1971-08-04 1972-09-05 Atlas Copco Ab Spray gun
US3698636A (en) * 1970-05-06 1972-10-17 Graco Inc Device for the electrostatic application of protective coatings with synthetic powders by the use of spray guns
US3711022A (en) * 1969-10-20 1973-01-16 Glick L Electrostatic coating apparatus
US3731145A (en) * 1970-11-23 1973-05-01 Nordson Corp Electrostatic spray gun with self-contained miniaturized power pack integral therewith
US3740612A (en) * 1971-05-28 1973-06-19 Champion Spark Plug Co Apparatus for coating with electrostatically charged particulate materials

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3263127A (en) * 1961-04-14 1966-07-26 Sames Mach Electrostat Means for electrostatic coating
US3248606A (en) * 1961-12-08 1966-04-26 Sames Mach Electrostat Apparatus for dispersing and electrically charging substances in discrete particulate form
US3711022A (en) * 1969-10-20 1973-01-16 Glick L Electrostatic coating apparatus
US3698636A (en) * 1970-05-06 1972-10-17 Graco Inc Device for the electrostatic application of protective coatings with synthetic powders by the use of spray guns
US3731145A (en) * 1970-11-23 1973-05-01 Nordson Corp Electrostatic spray gun with self-contained miniaturized power pack integral therewith
US3740612A (en) * 1971-05-28 1973-06-19 Champion Spark Plug Co Apparatus for coating with electrostatically charged particulate materials
US3688990A (en) * 1971-08-04 1972-09-05 Atlas Copco Ab Spray gun

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3892357A (en) * 1974-04-30 1975-07-01 Nordson Corp Electrostatic spray apparatus and method
US4380320A (en) * 1981-02-25 1983-04-19 Nordson Corporation Electrostatic powder spray gun nozzle
US4735360A (en) * 1983-04-07 1988-04-05 Kopperschmidt-Mueller Gmbh & Co. Kg Method and apparatus for electrostatic spray powder coating
US4798338A (en) * 1984-02-08 1989-01-17 Veb Infrarot-Anlagen Oranienburg Apparatus for the electro-kinetic charging of powdered materials
US4659019A (en) * 1984-05-30 1987-04-21 Ransburg-Gema Ag Spray device for coating articles with powder
US4660772A (en) * 1984-09-26 1987-04-28 A. O. Smith Corporation Electrostatic powder spray gun nozzle
US4798340A (en) * 1986-01-14 1989-01-17 Esb Elektrostatische Spruh- Und Beschichtungsanlagen G.F. Vohringer Gmbh Electrostatic device for powder spraying with triboelectric powder charging
US4784331A (en) * 1987-05-27 1988-11-15 Nordson Corporation Electrostatic spray gun device and cable assembly
US4811898A (en) * 1987-09-21 1989-03-14 Nordson Corporation Electrostatic powder spray gun with adjustable deflector and electrostatic shield
US5351903A (en) * 1993-04-06 1994-10-04 Russell Mazakas Electrostatic powder paint gun with trigger control variable voltage
USD397421S (en) 1995-10-31 1998-08-25 Wagner International Ag Powder spray gun
USD441833S1 (en) 1998-11-26 2001-05-08 Itw Gema Ag Spray coating device
US20110095054A1 (en) * 2009-10-22 2011-04-28 Graham Hughes Plunger
US8499977B2 (en) 2009-10-22 2013-08-06 P. C. Cox Limited Plunger
USD673020S1 (en) * 2010-12-23 2012-12-25 P.C. Cox Limited Single Trigger dispensers for cartridges
US8528793B2 (en) 2010-12-23 2013-09-10 P. C. Cox Limited Actuator
US8607824B2 (en) 2010-12-23 2013-12-17 P.C. Cox Limited Valve and dispenser using the valve
US8616415B2 (en) 2010-12-23 2013-12-31 P.C. Cox Limited Dispenser
US8870093B2 (en) 2010-12-23 2014-10-28 P.C. Cox Limited Dispenser
US20180369878A1 (en) * 2017-06-26 2018-12-27 Citic Dicastal Co., Ltd Automatic powder cleaning system for mixed-line hub bolt holes and combined powder cleaning gun
US10639681B2 (en) * 2017-06-26 2020-05-05 Citic Dicastal Co., Ltd. Automatic powder cleaning system for mixed-line hub bolt holes and combined powder cleaning gun

Also Published As

Publication number Publication date
GB1388787A (en) 1975-03-26
BE812038A (fr) 1974-07-01
SE371942B (enrdf_load_stackoverflow) 1974-12-09
DE2312363A1 (de) 1973-09-27

Similar Documents

Publication Publication Date Title
US3819115A (en) Electrostatic spray gun
US4380320A (en) Electrostatic powder spray gun nozzle
US3169882A (en) Electrostatic coating methods and apparatus
EP1614479B1 (en) Electrostatic coating spray gun
CA1264015A (en) Flat spray nozzle for a spray gun
ATE118375T1 (de) Spritzpistole für elektrostatisches pulver mit einstellbarem deflektor und elektrostatischem schirm.
US5636798A (en) Electrostatic spray device
AU603315B2 (en) Electrostatic spray gun device and cable assembly
US6874712B2 (en) Swirl gun for powder particles
JPH0510983B2 (enrdf_load_stackoverflow)
US3645447A (en) Electrostatic paint spray system
GB1310284A (en) Spray guns
US2960273A (en) Electrostatic spray painting apparatus
AU2004201870B2 (en) Spray coating device for spraying coating material, in particular coating powder
US3667675A (en) Electrostatic powder coating apparatus
US2966310A (en) Electrostatic deposition spray means
US3587967A (en) Spray coating apparatus
US6758424B2 (en) Low voltage electrostatic charging
US20150231652A1 (en) Grounding rods for electrostatic spray
US3210008A (en) Electrostatic spray coating apparatus
GB1038865A (en) Improvements in electrostatic spraying apparatus
US20050098659A1 (en) Swirl gun for powder particles
US3630442A (en) Electrostatic coating method and apparatus
GB1301304A (enrdf_load_stackoverflow)
JP2004330192A (ja) 塗布材料の放出装置