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Publication numberUS1633291 A
Publication typeGrant
Publication dateJun 21, 1927
Filing dateSep 7, 1926
Priority dateSep 7, 1926
Publication numberUS 1633291 A, US 1633291A, US-A-1633291, US1633291 A, US1633291A
InventorsOlsen Einar E, Sausen Bert R
Original AssigneePeerless Pneumatic Systems Inc
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Spray gun
US 1633291 A
Abstract  available in
Images(2)
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Claims  available in
Description  (OCR text may contain errors)

SPRAY GUN Filed Sept. '7, 1926 2 Sheets-Sheet 1 Zr van for; jerk June 21, 1927.

B. R. SAUSEN- ET AL SPRAY GUN Filed Sept. 7., 1926 2 Sheets-Sheet 2 ,TZ/ZZ QJ 20 4/ I :8 M t 0w Sm BIC F M Efqar 5.041!) Patented June 21, 1927.

UNITED "STATES BERT R. SAUSEN AND EINAB E. OLSEN,

LESS PNEUMATIC SYSTEMS INC., OF CHICAGO,

SPRAY GUN.

ILLINOIS,

OF CHICAGO, ILLINOIS, ASSIGNOES T0 REEB- ILLINOIS, A CORPORATION 0] Application filed September 7, 1926. Serial No. 134,114.

Our invention relates to the class of spraying appliances designed for projecting liquids in the form of a finel divided spray of predetermined form. an density, such as the so-called spray for spraying paints, varnishes and the like.

Where such a coating material is to be applied in a uniformly dense distribution to surfaces of large area, it is customary to employ aspray gun in which the paint or other liquid is first projected in a cylindrical stream and is then flattened by jets of airdirected against opposite sides of the projected stream. To keep the projected stream from enlarging in diameter before it is reached by the attening jets of air, this stream is commonly housed by a tubular sheath of air which is projected through an annular spacebetween the paint nozzle and the bore of an air nozzle. In practice, the paint nozzle and the air nozzle are usually supported independent of one another,and unless great accuracy is employed in the construction of the ap liance, these two nozzles are not coaxial. hat is to say, the two nozzles may have'their axes parallel but relatively shifted, or these .axes may be at an angle to each other. In every such instance the tubular air sheath is not uniform in thickness and hence will permit the stream of liquid within it to spread out of a true cylindrical section, so that the flattenin air jets will not produce the desired uniformity in fan of spray.

Moreover, the air ports for the flattening air jets are usually formed in the samevair nozzle which has its bore defining the initial contour of the tubular sheath of air, so that any relative shifting or tilting of the axis of the air nozzle with 'respectto the axis of the paint nozzle spoils the symmetry of the flattening air jets with respect to the stream of paint projected'through the axial bore'of the paint nozzle. This also alters the distribution of the spray inthe resulting sheet or fan of spray.

Our present invention aims to overcome both of these difiiculties by providing a spray-appliance head construction in which g the air nozzle is accurately almed and oen-.

tered b the liquid nozzle, and aims to accomplis this in a construction which will constituent parts.

guns employed the resulting sheet or not require an unusual degree of accuracy in the manufacture or assembling of the Furthermore, our invention aims to provide a spraying appliance of this class in which the air nozzle is clamped upon the liquid nozzle by an attaching collar and in which the ports for the flattening jets of air are formed by rooves out either in the exterior of the liquid nozzle or in the bore of the attaching collar. In the constructions of that type, it is important that the joint between the attachin collar and the paint nozzle be ti htly sea ed except forthe said grooves, an particularly adjacent to these grooves, as any air issuing forwardly at other points of the junctures between these two nozzles will project spray inv undesired directions so as to produce oil spray spottings which mar the uniformity of the resulting coating.

Illustrative of our invention Fig. 1 is a central, vertical and longitudinal section through the forward portion of a spray gun designed for producing aflat spray and embodying our invention.

'Fig. 2 1s an'enlargement of the forward portion 9f Fig. 1, with the liquid nozzle shown in section.

' Fig. 3 is a side elevation of the air nozzle of this spray gun.

Fig. 4 is front elevation of this air nozzle member. I

Fig. 5 is a section similar to the forward portion of Fig. 1, showing another embodiment of my invention, namely one in which an auxiliary sleeve secures the attaching collar to the body of the spray gun, and in which the grooves for the flattening air jets are cut in the bore of the attaching collar. Fig. embodiment in which 6 is a similar section, showing an the ports for the flattoning air jets are formed by bores extending throu h parts of the air nozzle.

"Fig. 7 is a ragmentary section along the line of 5-5 of Fig. 5.

In the embodiment of Figs. 1 to 3 inclusive, the forward or head end of the spray un bod 1 has a longitudinal bore 2 through which e aint is supplied and a separate passage 3 {hr the compressed air. The forward end of the bore 2 is threaded to match the male thread on the rear portion 4 of a liquid nozzle 4 which has an axial bore 5, and the forward end of this paint nozzle 1s contracted in diameter to form a tubular liquid outlet 6. The forward portion of the bore 5 is correspondingly contracted and has a forwardly tapering bore portion affordin a tight seat for the tapering forward end of the usual needle valve stein 7 which controls the discharge of the paint or other li uid.

e exterior of the liquid nozzle 4 has a forwardly tapering frustro-conical portion 4 disposed between the threaded rear portion 4* and the paint outlet 6. Sleeved upon this tapering portion 4: is an air nozzle which is here shown in the form ,of a perforate cap comprising a tubular rear portion 8 bored to fit the taper of the said exterior nozzle surface 4 and a head 9 having a bore 10 somewhat larger in diameter than the exterior of the tubular liquid outlet 6. This liquid outlet extends into, and desirably entirely through the said bore 10 so as to leave an interposed annular port 14 through which the tubular air sheath is projected. To supply air for this sheath, we provide the tubular portion 8 of the nozzle member with perforations 11 leading to aspace 12 back of radially outer part of the head 9 and in front of a portion of the air nozzle. These perforations 11 preferably have their axes in planes radial of .the nozzle member and we desirably provide a large number of such perforations, all leading to an annular space 24 behind the head 9 and in front of apart of the air nozzle 4. By doing so, we can utilize this space 24 as an air supply chamber for projecting a tubular air sheath at high pressure through the annular air port 14, while making this port 1 1 so narrow (radially of the nozzle) as to require a comparatively small amount of air for the tubular air sheath projected through it.

To hold the air nozzle member socketed upon the tapering part of the liquid nozzle, we employ a retaining collar which snugly fits a part of the air nozzle so as to aline itself with the latter, and we secure this collar to the body member of the spray gun by attaching means which will permit the collar to adjust itself to this alining. With this in mind, Fig. 3 shows the air nozzle as having its forward peripheral surface portion 15 of a forwardly tapering frustroconical shape, this surface being coaxial with the taper in the tubular part 8 and the bore 10. Fig. 1 also shows the attaching collar as comprising a tubular rear part 16 and a forwardly tapering contracted end 17 which is bored out to have its rear face match the taper of the portion 15 of the air nozzle member. The rear end of the main collar part 16 is threaded upon the forward end of the gun body 1, and this threaded connection is sufficiently loose so that the collar can rock or shift slightly on the gun bod Iii assembling the parts as thus described, the tapering fit of the air nozzle member on the liquid nozzle accurately alines these parts with each other, thereby disposing the bore 10 of the air nozzle member coaxial with the cylindrical exterior of the tubular liquid outlet 6. Hence the air forced through the annular port 14 issues in the form of an annular sheath of uniform thickness and accurately concentric with the liquid projected through the bore of the liquid outlet 6.

When the collar has its rear end screwed under the gun body, the tapering rear face of its contracted forward end 17 seats upon the tapering surface portion 16 of the air nozzle "and automatically alines this collar with both the air nozzle and the liquid. outlet, while also insuring a tight' seal between the collar and the air nozzle. The tightness of this sealing also permits us to form the ports for the flattening air jets by grooves extending along the juncture of the inter-fitting tapered surfaces of the portions 15 and 17 in planes radial of the air nozzle member.

This we preferably accomplish by milling a pair of grooves 18 in the tapering portion 15 of the air nozzle, with the axes of the grooves in a common plane radial of this nozzle member and with the grooves diametrically opposite each other. By using a milling tool for cutting these grooves, we can readily secure groove edges free from burs and running snugly up to the inner face of the collar, thereby avoiding the issuing of any stray air such as would produce an off spray. So also, by merely providing a slight looseness of the threaded connection between the collar and the gun body,

we readilypermit the needed accurate alini ing of the heretofore described tapering portions without requiring the threading to he so loose as to permit air to issue at this connection, although any such leaking air would issue rearwardly and hence could not affect the spray.

By initially constructing the paint nozzle separate from the gun body, we facilitate the accurate-machining of this part. However, we do not wish to be limited to this or other heretofore described details of construction and arrangement, since many changes might obviously be made without departing either from the spirit of our invention or from the appended claims.

For example, the liquid nozzle 4 might be made integral with the gun body, as shown in Fig. 5, and the ports for the flattening air jets might be formed by grooves 25 milled in the tapering rear face of the forward collar portion 17 such as the grooves vided by a loose threading. Instead, we may provide the collar at its rear end with an outwardly directed annular flange 20, as shown in Fig. 5,and may secure the collar to the gun body by an auxiliary collar 21 which is threaded at its rear end upon the gun body 1 and which has a contracted forward end 21 engaging the front of the flange 20, this flange having a bore larger than the adjacent main portion lo of the collar. In

this case, we can readily inter-pose a packing rin 22 between the rear end of the collar an the forward end of the gun body 1', as also shown in Fig. 5, so as to obtain a tight sea'l'between these parts.

With each-of the illustrated embodiments, the width of each port for the flattening air (namely, the width of each groove 18 or 18, or the diameter of the bores 19) is preferably a 'little narrower than the bore of the paint outlet. By using this proportion, we avoid disru ting the liquid stream unduly through a g ancing action'of the lateral edge portions of the flattening air jets, while also avoiding a 'splittin of the stream such as would occur ifthe flattening jets of air were considerably narrower than'the diameter of this stream. However, both the dimensions of the grooves (or diameters of the ports if bored) and the radial width of the annular air port 10 may be varied according to the viscosity of the paint or other material which is to be sprayed. By using relatively long grooves with sides parallel to, but at opp0- site sides from, a plane radial of the pro-' jected stream of liquid, we can accurately predetermine the widths of the flattening jets of air, which we have not found feasible with bored air ports owing to the fact that even a minute enlargement of such a bore at its outlet has amaterial effect on the crosssection of the issuing jet of air.

Furthermore, by forming two grooves of uniform depth in the same taperingsurface,

gwe can easily produce air orts having their .the axis of the air nozzle.

axes directed to exactly t e same point on This is not so feasible'with drilled air ports, as each port has to be drilled separately and even a sllght wearing of the jig for guiding the drill will permit variations which show a considerable effect on the uniformity of the spray. By combining this accurate dimensioning and directin of the flattenin air jets with a uniform thickness of the tu ular air sheath, we are able to secure the long desired uniformity of distribution of finely divided paint in a flat (or substantially fiat) spray.- Hence we eliminate the manual touching up of surfaces upon which a coating has been sprayed and likewise avoid the spotty effects heretofore encountered on account of'the s0- 'oalled off spray. Moreover, we accomplish these results by employing a spray gun head construction comprising quite few parts and having each of these parts so designed that any reasonably skilled machinist can readily manufacture them with a suf ficient degree of accuracy.-

However, we do not wish to be limited to the embodying of the various features of our invention in a hand appliance of the socalled spray gun type, nor to the use of our invention for spraying paints or varnishes.

We claim as our invention:

1.,In a-liquid spraying appliance, a body member having a forwardly tapering portion and a liquid passage extending through and coaxial with the said tapering portion, a cap-like air nozzle having a forwardly ta-' pering bore extending into it from its rear end and tapered to fit the tapering portion of the body member, the air nozzle having an outlet bore coaxial with and leading forwardly from its tapering bore and freely hous ng the forward end of the tapering portlon of the body member, the air nozzle raving a forwardly tapering frustro-conical outer Wall coaxial'with its tapering bore and hav ng passages leading to its bore from the peripheral portion of the air nozzle behind its said frustro-conical wall; and a retaining collar secured to the body member and having a part thereof spaced from the air nozzle to provide an air space therebetween, the body member having an air passage leading to the said space, the collar havinga contracted front end tapered on its rear face to fit u on the frustro-conical wall of the air nozz e; the securing of the collar to the body member being such as to permit relative 'movement thereof to allow a firm seating of the interfitting tapering parts of the body member, the air nozzle and the collar.

2. A liquid spraying appliance as er claim 1, in which the air nozzle is .provi ed on its frustro-conical wall with a pair of diametrically opposite longitudinal grooves.

3. A liquid spraying appliance as er claim 1, in which the air nozzle is provided on its frustro-conical wall with a pair of diametrically opposite longitudinal rooves extending for the entire len th of t e said wall, the lateral walls of eac groove being both parallel to a plane diametric of the air nozzle and medial of the groove.

4:. A liquid spraying appliance constructed as per claim 1 and havmg a pair of diametrically opposite air ports extending through the air nozzle from the said air space and directed toward a common point forwardly of the air nozzle and on the axis of the nozzle.

5. A liquid spraying appliance including a liquid nozzle, an air nozzle fitted upon the liquid nozzle, the interfitting parts of the two nozzles comprising forwardly tapering frustro-conical seats coaxial with the nozzles; an air confining collar having a portion thereof fitted upon the air nozzle, the said collar portion and the part of the air nozzle fitted upon it comprising forwardly tapering frustro-conical seats coaxial with the air nozzle and collar; and securing means rigidly connecting the collar to the liquid nozzle, the said means being arranged to permit relative movement of the collar and liquid so as to permit an accurate alining and tight seating of the said interfitted parts during the fastening of the securing means.

6. A spray gun comprising a body memher, a liquid nozzle projecting forwardly from the body member and smaller in diameter than the adjacent part of the body member, the liquid nozzle having a forwardly tapering frnstro-conical portion and a cylindrical outlet part'extending forwardly from the said portion and having a bore coaxial with the said portion and part; an air nozzle having a forwardly tapering bore tapered to fit upon the frustro-conical portion of the liquid nozzle and having coaxial therewith an outlet bore larger in diameter than the outlet part of the liquid nozzle and housing the said part, the air nozzle also having coaxial with its outlet bore a peripheral and forwardly tapering frustro-conical wall; a retaining collar having a contracted forward end tapered on its rear face to fit the said wall. and having another portion freely housing the air nozzle to provide an air space therebetWeen, the body member having an air supply passage leading to the said space, the air nozzle having ports connecting the said space with its'outlet bore and also having a pair of diametrically opposite passages extending to the front of that nozzle from the said space and directed toward a common point disposed on the axis of the air nozzle forwardly of that nozzle; and securing means operatively interposed between the collar and the body member, the said means being arranged to permit a relative rocking and shifting of the collar and body member so as to allow a'tight interfitting of the tapering air nozzle portions with the tapering portions of the liquid nozzle and collar.

Signed at Chicago, Illinois, September 1nd, 1926.

BERT R. SAUSEN. EINAR E. OLSEN.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4407450 *Oct 30, 1980Oct 4, 1983Chegolya Alexandr SMethod of aerodynamic production of liquid and solid disperse aerosols
US6170760Jan 25, 1999Jan 9, 2001Precision Valve & Automation, Inc.Compact spray valve
US6523757Nov 2, 2000Feb 25, 2003Precision Valve & Automation, Inc.Compact spray valve
US7028867 *Oct 30, 2003Apr 18, 2006Nordson CorporationConformal coating applicator and method
US7422772Jan 12, 2006Sep 9, 2008Nordson CorporationConformal coating applicator and method
EP0589075A1 *Sep 22, 1992Mar 30, 1994Mattson Spray Equipment, Inc.Air directing ring for fluid spray gun air cap
EP0654305A1 *Oct 25, 1994May 24, 1995Itw LimitedAn improved spray nozzle
WO2002074446A1 *Feb 28, 2002Oct 30, 2002Duesen Schlick GmbhExternal mixing nozzle
Classifications
U.S. Classification239/300
International ClassificationB05B7/02, B05B7/06, B05B7/08
Cooperative ClassificationB05B7/066, B05B7/0815
European ClassificationB05B7/08A1, B05B7/06C3