US2146416A - Spray gun nozzle - Google Patents

Description

Feb. 7, 1939. s, BRAMSEN r AL 2,146,416

SPRAY GUN N OZZLE Original Filed Oct. 3l, 1935 2 Sheets-Sheet l @j /v 52 6 /V l a f ,I l vlll11n,l,///////////// nl I Jz den 26075 5de/zd milzen Feb. 7, 1939. S BRAMSEN E1- AL 2,146,416

SPRAY GUN NOZZLE Original Filed Oct. 5l, 1935 2 Sheets-Sheet 2 Patented Feb. 7, 1939 spaar GUN NozzLE Svend Bramsen and Fred W. Wahlin, Chicago, `lll., assignors to Binks Manufacturing Company, Chicago, Ill., a corporation of Delaware Original application October 31, 1935, Serial No.

47,58%, Divided and this application November 8, 1937, Serial No. 173,365

13 Claims.

` Our invention relates to novel structural features of a spray gun and in general aims to accomplish the following objects:

(1) Providing improved rearward guide and 5 adjustable pressure provisions for the needle valve which controls the discharge of material from the material nozzle, -to prevent this valve from binding if the valve is not exactly straight or if the forward and rearward guides are not in l exact axial alinement.

` (2) Providing a mounting for the said rearward guide and adjustable pressure provisions associated with the needle valve which will permit the major parts of this assemblage to be ati tached to, and detached from, the gun body as a unit.

` (3) Providing simple and effective means for transmitting `digital pressure on the trigger of the gun to the needle valve, and for preventing dust from entering operative portions of this rearward guide.

(4) Providing an effective head andseat `for the supplemental air valve which controls the supply of spray-flattening air to the side ports 5 of the air nozzle, and an effective guide for this valve head.

(5) Providing a duplex seating of the material nozzle on longitudinally spaced portions. of the `head of the gun body to insure an exact alinement of this nozzle with the said head, as well as an airtight seating of this nozzle on the gun head, even if the threaded connection of this nozzle to the said body head is not perfectly accurate and right.

` (6) Providing air passageways in a forward body part of the gun for affording an ample air supply to longitudinal air passages in the air nozzle of the gun.

taching ring interposed between the air nozzle and the gun body will permit an accurately axial seating of this air nozzle on the materialnozzle even if the threaded connection of the said ring to the gun body is not exactly coaxial with the material nozzle.

(8) Providing simple means for stiffening a tubular frontalpart of the gun into which the material nozzle is threaded, and utilizing the said means fo distributing air to numerous longitudinal a r passages` formed in the material nozzle. h

. (9) Providingsimple, durable and easily replaceable means for reducing wear on the parts of the trigger of the gun which respectively engage the stem of the main air valve and a pressure-transmitting` member associated with the needle valve.

Illustrative of the manner in which we accompush the ebeve recited objects,

Fig. 1 is a central, vertical and longitudinal 5 section through a spray gun embodying our invention, with the usual suspension hook and the major portion ofboth the handle and the trigger of the gun broken away.

Figure 2 is an enlargement of the forward por- 10 tion of Fig. l.

Fig. 3 is a similar enlargement of the forward part of the gun body alone.

Fig. 4 is a further enlargement of an upper portionof Fig. l, showing the means which seal 15 the forward end of the attaching ring to the air nozzle while permitting` a `rocking of the ring with respect to the said nozzle.

Fig. 5 is a side elevation of the material nozzle, and Fig. 6 a rear elevation of the same nozzle. 20

Fig. rikis a fragmentary enlargement of a considerable` portion of Fig. 1, drawn on the same scale as Fig. 2.

Fig. 8 is a fragmentary and enlarged section `taken along the line 8--8 of Fig. 7 through the 25 trigger and parts adjacent thereto.

Fig. 9 is a similarly enlarged rear perspective view of the presser plate attached to the main part of the trigger.

Fig. 10 is an elevation of the rearward portion 30 of the material-discharge controlling needle valve, the presser member threaded on this valve, and the cap-nut which latches the presser member in its adjusted position, drawn on the same scale as Fig. 7. 35

Fig. 11 is an elevation of the unitarily detachable assembly of parts of the control unit associated with the needle valve. ('l) Providing effective means whereby the at- Fig. l2 is a rear elevation of the portions of the gun, shown in Fig. 1. 40

Fig. 13 is a front elevation ofthe forward gun body part which is separately shown in section in Fig. 3, drawn on the same scale as Fig. l.

Fig. 14 is an enlarged radial section of a portion of the front end of the slidable thrust sleeve 45 through which pressure on the trigger ofthe gun is transmitted to the presser member on the needle valve. y

Fig. 15 is a central and longitudinal section through the adjusting tube and the parts carried 50 thereby, showing this assemblage when the tube has been detached from the gun body to permit an adjusting of the effective length of the needle valve.

In the illustrated embodiment, the main body 5g part of our gun includes a barrel or stock S having the usual longitudinal main air passage M,` a tail portion 23 (Fig. 12) depending from the rearward portion of this stock, and a handle H depending from this tail portion. The companion forward body part F, shown almost completely in section in Fig. 3, has a flat rear face portion f bearing against the iiat forward end of the stock, and the forward body -part also has a rearwardly projecting boss B extending through a longitudinal bore in a lug L depending from the forward end of the said stock.

A doubly threaded nipple N clamps the forwar body part tightly againstthe'main body part, after the manner more fully described in our Patent No. 2,107,726, issued Feb. 8. 1938 on a. Spray Bim.

The forward portion of this nipple is threaded into the rearward portion Ia of an air bore I from which a passage 2 leads forwardly to a forwardly open annular channel I formed in the radially outward frontal portion of the forward body part, as shown in Figs. 3 and 13. This forward body part also has a deeper forwardly open channel 4 concentric with and radially inward of the channel 3, into which channel 4 the air bore I also opens; and the body portion within the inner wall of the deeper channel I has an axial bore 5a forming the forward arm of an elbowed material passage I', which passage has its inlet in a tubular shank 1 depending from the main portion of the forwardv body part.

The said axial bore 5a has its forward portion provided with a non-tapering thread Ib and also has a more rearward and rearwardly tapering bore portion Bc,'and the portion of the forward body part in which the said axial bore 5a is formed has its forward end spaced rearwardly from the front face of the radially outward portion of this body part in which the outer annular channel l is formed. Moreover, the outer wall of the inner channel l has a portion 4a flaring forwardly and preferably in the same conical surface with the said tapering portion lc of the axial bore in the frontal body part.

This aiming of two peripheral, longitudinally spaced and coaxial portions of the frontal body part of our gun permits the said portions la and 5c to afford zone-like annular seats respectively for a midlength peripheral portion la and a rear end peripheral portion 8b of the material nozzle of our gun (shown separately in Figs. 5 and 6) when the said nozzle portions present their peripheries in a conical surface of the same cone angle 9 (Fig. 5) as that in which the tapering portions 4a and 5c were bored. Moreover, the longitudinal spacing between each set of these tapering portions permits a non-taperingly threaded portion lc of the material nozzlev to be screwed into the similarly threaded portion 5b of the frontal body part.

With the previous construction of such spray appliances, the disposition of the axis of the material nozzle with respect to the body part which supports this nozzle, varied according to the extent to which the thread on the nozzle approached an exact alining with the axis of the nozzle, and also on the accuracy with which the corresponding bore in the gun body was threaded. And, since the thread on the nozzle was usually on the extreme rearward portion of the shank of the nozzle, a departure from the intended axial alinement of this nozzle with the corresponding air nozzle of the gun was often magnified to such an extent at the front of these nozzles as to dispose the outlet tip of the maport of the air nozzle, thereby producing a correspondingly distorted pattern of the projected spray.

With our here presented arrangement, the annular tapering seats 4a and loin the forward body part can readily be formed in a single operation with a boring tool which has corresponding portions accurately ground to the desired common taper angle, and the annular surfaces 8a and 8b on the material nozzle can both be ground accurately and by a single operation to the same common taper angle. Consequently, the straight-threaded connection between the nozzle shank portion 8c and the body bore portion Ib can be sumciently loose to permit both of the said nozzle surfaces to seat firmly and to insure an exact positioning of the nozzle. This allows also for manufacturing variations in the nontapering threadedly interconnected parts. so as to insure an equally proper supporting of material nozzles which have been made at different times.

I'he companion air nozzle I 0 is desirably of a cap type, bored to fit upon a forwardly tapering frustro-conical portion ld of the material nozzle which is forward of the oppositely tapering portion 8; and the air nozzle has the usual central air port p into which the usual tubular tip lt of the material nozzle freely extends, as well as the usual peripheral head Nb. This nozzle is clamped rearwardly on the material nozzle by al retaining ring I I which has its rear end portions screwed upon a peripheral thread ld on the forward end of the forward body part, the forward end of which ring presents an interior annular flange I Ia in front of the bead IIb on the air nozzle.

To compensate for manufacturir; variations in the fit of the retaining ring on the forward body part, to seal the retaining ring adequately to the air nozzle, we interpose a metal gasket I2 (desirably of bronze) between the interior flange I Ia of the retaining ring and the front of the bead Ib on the air nozzle. We also preferably form the rearward portion of the bore of this flange so as to iiare rearwardly and to present a rearwardly concaved annular face shaped as a zone of a spherical surface which has its center point approximately at the apex SII (Fig. 2) of the conical surface of which the annular nozzle seats 4a and 5c form a part, and form the gasket I2 of an approximately quartercircular section presenting a curved section to the said interior ange and presenting a flat rear face yto the peripheral flange IIIb on the air nozzle.

In addition, we preferably provide a second interior flange IIb on the retaining ring, somewhat rearward of its said end flange Ila, this second flange having its bore diameter intermediate that of the bores of the aforesaid flanges IIa and IIb.

With the parts thus constructed, the gasket can readily be snapped into the forward portion of the retaining ring, from the rear of that ring, so as to be held in the latter by th'e rearward flange lib when the retaining ring is detached. When this retaining ring and gasket assembly is slipped over the air nozzle (after the latter has been socketed on the material nozzle as in Figs. 1 and 2) the intei'engaging sphere-zone surfaces of the flange on the retaining ring and of the gasket permit the retaining ring to rock on `terial nozzle decidedly eccentric to the central' and the material nozzle has a plurality of circumferentially spaced longitudinal passages 8e leading to this space. In addition. the material nozzle preferably also has an annular groove 8h in its rear end, from which the said passages lead. This groove faces the inner annular chanimportant purpose of stiffening the tubular body nel 4 in the front end of the gun body, to which air is supplied through the air bore I in that body, so that this groove co-operates with the said channel in distributing air to the said passages.

To equalize this air distribution we dispose an annular bame of smaller area (in a plane at `right angles tothe axis of channel) in the said channel l and preferably in the forward portion of this channel, so as to cause the air to flow circumferentially to a considerable extent before reaching the mouth end of the channel.

For this purpose we preferably employ a metal baffle ring I5 press-fitted on the tubular body portion which' has the interior thread 5b, this ring preferably being considerably wider than its maximum thickness andpreferably decreases in thickness rearwardly, from a maximum thickness somewhat less than the width of the annular channel 4 in which the said ring is located.

Thus disposed, the baffle ring I5 also serves the portion on which it is mounted, to permit that body portion to be accurately bored without danger of cracking it, even when the thickness of the tube wall is rather small so as to reduce the diameter of the head portion of the forward body part.

When the air nozzle is to effect a flattening of the spray, the rearwardly tapering portion 8 of the material nozzle preferably is of such length as to extend forwardly for a considerable dis- "tance beyond the front end of the gun body, and

this tapering portion is spaced from the rear end of the forwardly tapering portion 8d by a peripheral groove disposed adjacent to the rear end of the air nozzle. This permits air admitted from the outer annular body channel 3 to the annular space between thel front end of the gun body and the rear end of the. air nozzle to flow through longitudinal passages II in the rear end part to the .air nozzle for reaching the side air passages I8 `of that nozzle.

The side air for this purpose is supplied (after the manner more fully described in our Patent No. 2,107,726, issued Feb. 8, 1938) from the main air passage M through the inlet bore I and a port P leading forwardly from the latter, this portbeing controlled by the head V1 of a sideair control valve V which can be adjusted by a rearward knob'V.

Moreover, we preferably construct our material nozzle so that the rear end of the air nozzle will be spaced forwardly from the doubly channeled forward end of the gun body (by a space 4i) when the air nozzle seats on the material nozzle, so that this space around the material "nozzle will co-operate with the outer channel 3 in equalizlng the air distribution to the side air passages I8 of the air nozzle.

To control the discharge of material from the material nozzle, we employ a simple rod-like needle valve I3 extending rearward axially through the body boss B, and through an annular packing I9 disposed in a rearwardly open bore in the said boss. This packing is compressed around the needle valve by a plunger or' gland 20 which slidably fits the rearward portion of the said bore in the body boss and which gland is fastened to the head of a stuffing box cap 2l threadedon the rear end of the said boss B. To effect this fastening, which permits the gland to be detached along with the stuffing box cap 2l we form the gland with a diametrically rearward extension 20a which extends through and is flared out into a rearwardly flaring axial bore ,in the head of the said cap, as shown in Fig. 2.

Moreover, the axial bore 20h of the gland 20 of the forward gun body part is preferably somewhat larger in diameter than the needle valve, so as to avoid any cramping of this valve. Then we also provide the following novel arrangement in the more rearward part of our spray gun for guiding theneedle valve in such a manner as to avoid any binding or cramping of that valve, while permitting` the needed adjustments and also facilitating a disassembling of the control provisions associated with that valve.

The pivoted trigger T of the spray gun de- Y pends in the usual manner in front of the handle H and of the usual tail portion 23 which con- I nects the stock S to this handle, and the saidtail portion has a bore 2l coaxial with the needlevalve-guding bore 22 in thc forward body part and with the material nozzle. Mounted in this bore is a sleeve (Fig. 11) which has a portion 25 fitting the rear end of the said bore, a mid-length portion 25a threaded into that bore and a peripheral flange 25h normally bearing against the rear end of the body tail portion 23.

The more forward portion of this sleeve presents a peripheral flange 25c` behind a contraction 24a of the bore 24, which flange is sealed to the shoulder affording that contraction by `a gasket 26 as shown in Fig. 7. In addition, the

sleeve has a cylindrical portion 25d fitting into the said bore contraction 24a, and the sleeve extends forwardly through the latter to present its forward end portion 25hin front of the adjacent portion of the tail 23. Threaded on this portion 25h is a retainer ring 28 which bears rearwardly against the said tail portion and which also clamps the radially outer portions of two annular wipers 21 against the front end of forward sleeve portion 25h while permitting the radially inward portions of the wipers to flare away from each other longitudinally of the said sleeve. a

'Ihe part of the said sleeve forward of its midlength threaded portion 25a has a bore 30 con siderably larger in diameter than the needle valve I3, through which bore a presser tube 3| slidably extends. This tube has an annular head 32 clinched to it as shown in Fig. 14, and has the wipers 21 tting against it to prevent dust from entering the sleeve bore 30 to interfere with a forward portion of the said cap nut is a ring 35, which freely houses the forward portion of the cap nut 34. This ring is slidable in the bore of an adjusting tube 3B which has a midlength part threaded into the rearward portion of the bore of the sleeve 25. The rear end of the adjusting tube is normally closed by a cap 31, which cap has its rear end portion 36h enlarged and peripherally knurled, and a compression spring 38 interpod between the said cap 31 and the slidable ring 3l continually presses the said ring forwardly.

If the bore of the slidable ring 35 were slidably fitted upon the cap nut 34, this interfitting would hold the adjacent part of the needle valve coaxial with the guide sleeve 36. Consequently, any deviation from an exact axial straightness of the needle valve, such as frequently occurs owing to a bending of such valves while they are being hardcned, would cause the heretofore frequently encountered cramping (and even sticking) of this valve which interferes with the normal operation of the gun. But with the bore of the ring 35 suitably larger than the diameter of the cap nut portion housed by it, we accomplish the following result:

When the adjusting tube 36 is unscrewed from the sleeve 25, this tube (together with the spring 38, the presser ring 35 and the cap 31) are detached as a unit, as shown in Fig. 15, this being permittedby making the bore 36o in the forward end of that tube larger in diameter than the head 33a of the presser head 33. The needle valve, with this presser head and the locknut 34 still mounted on it, as in Fig. 10, can then be slid manually rearward fork adjusting the position of the presser head on this valve.

To insure a substantial axial rearward pressure of the trigger on the frontal head 32 of the presser tube, we provide the trigger proper (T) with a flat rear portion face 'I'2 extending in front of both the said tube head and the usual stem 42 on the air valve 40, and also provide the trigger proper with a dat upwardly facing shoulder at the lower end of the said flat rear face portion.

Then we provide a presser plate 43, shaped as in Fig. 9, which is preferably of hardened steel while the trigger may be of aluminum alloy. This presser plate has a lower flat end and has a forked upper portion presenting two fork fingers 43a, spaced by a distance greater than the diameter of the needle valve i3, so that the said valve can extend freely between them. These fingers 43a have their rear faces formed as portions of a common cylindrical surface having a horizontal axis intersecting the axis of the needle valve. When this presser plate is positioned against the said fiat face portion of the main trigger portion with the lower end of the plate bearing against the shoulder T1, a single screw 44, desirably clinched to the trigger proper, suffices for fastening lt rigidly to the latter. Then when the trigger is retracted, the rear faces of the plate prongs 43a bear simultaneously against the tube head 82 substantially on a line diametric of that head, so as to effect an axial thrust on the slidable tube 3l.

By using the above described featuresy conjolntly in a spray gun, we obtain the following advantages ovex` the now commercial guns:

(1) A generally straight path of the air flow through the air inlet I of the forward body part and from the latter both through the longitudinal air passages in the material nozzle and to the y side air passages of the air nozzle.v

(2) A tightly sealed andflnn mounting of the material nozzle, regardless of the flt of the threads which automatically adjusts itself to any lack of an axial'straightness of that valve.

(7) A transmitting of the trigger pressure to a part of the needle valve far behind the trigger, so as to leave that valve free between the presser member 33 and the forward guide bore 22.

(8) Preventing dust from interfering with a free sliding of the presser tube 3i, which we accomplish by the wipers 21.

(9) Insuring a non-tilting longitudinal thrust on this presser tube, by providing it with an enlarged forward head engageable by the convexed finger portions 43a of the presser plate on the trigger.

(10) Guarding against a tampering with the needle valve adjustment. Since the cap 31 of the adjusting tube3 has a smooth rear head, as shown in Fig. l2, the interior screw-driver receiving slot 31a on this cap is not exposed for tempting an inexperienced gun user to turn this cap.

However, we do not wish to be limited to the conjoint use of the here disclosed features of our invention, or to the heretofore described desirable details of construction and arrangement,- as for example, to the use of the two-piece air nozzle member constituted by the air nozzle and the retainer ring-since many changes could obviously be made without departing either from the spirit of our invention or from the appended claims.

This is a division of our copending application Ser. No. 47,580, led October 3l, 1935, now Patent No. 2,102,303, issued Dec. 14, 1937, for Spray gun valve.

We claim as our invention:

l. In a spray gun, a gun body having its front end formed to present a tubular portion surrounded by an annular and forwardly open channel coaxial with the said tubular portion, and having a material passage and an air passage leading respectively to the bore of the said tubular portion and to the said channel, the outer wall of the said channel having its forward portion flaring forwardly; a material nozzle having a tubular shank the rearward portion of which is socketed in the said bore, and having a rearwardly tapering exterior portion seated on the said flaring portion of the outer channel wall; the said material nozzle having longitudinal air passageways communication with the said channel.

2. In a spray gun, a gun body and material nozzle assemblage as per claim 1, in which the said flaring channel wall portion is farther forward than the front end of the said tubular body portion.

` 3. In a spray gun, an assemblage as per claim 1, in which the shank ofthe material nozzle is threaded into a part of the bore of the tubular portion, and in which the said bore and the said shank have tightly interiltting parts disposed rearwardly of the threading of the said shank into the said bore.

4. In a spray gun, an assemblage as per claim 1, in which the shank of the material nozzle has a rearwardly tapering exteriorly frustro-conical rear end portion; and in which the said bore has a portion thereof formed to afford a seat engaged by the said rear end portion of the shank of the material nozzle.

5. In a spray gun, an assemblage as per claim 1, in which the shank of the material nozzle has a rearwardly tapering frustro-conical exterior portion; and in which the said bore has a portion thereof formed to afford an annular seat engaged by the said tapering portion of the shank of the material nozzle, the said seatand the said flaring portion of the outer channel wallbeing formed as parts of a common conical surface.

6. In a spray gun, an assemblage as per claim 1, including a ring fitted upon the said tubular portion of the gun body and disposed within the said channel, the ring being oi' less thickness than the width of the said channel and serving as a baille for distributing air circumferentially of the channel to the said air passageways in the material nozzle.

7. In a spray gun, an assemblage as per claim 1, including a ring sleeved upon the forward end of the said tubular portion of the gun body, the said ring decreasing rearwardly in thickness and has its maximum thickness appreciably less than the radial width of the said channel.

8. In a spray gun, an assemblage as per claim 1, including an annular baille'disposed in the said channel and supported by a wall of that channel, the said baille being of smaller area, in a section at right angles to the axis of the said chan- "nel, thanv the cross-sectional area of the channel.

9. In a spray gun, a body having its front end provided with a central and forwardly open bored part and having two forwardly open channeled parts-concentric with the said bore: the body also having an interior air chamber opening into the inner channel and having a port connecting said air chamber to the inner channel; a material nozzle having its rear end portion socketed in said bored part and having a peripheral portion, intermediateof the ends of the said nozzle, seated on a forward part of the said body between the two channels of the channeled parts, said nozzle having longitudinal air passages open at their rear toward the inner of the said channels; and an air nozzle member fitted both upon a part of the material nozzle forwardV of 'said peripheral portion of the latter and upon the periphery of the said forward body end; the air nozzle member having side air'passages extending through it, and being formed to afford an annular air chamber in front of the outer of the said channels, from which air chamber the side air passages lead.

10. In a spray gun, a gun body including a. forward part presenting a forwardly opening tubular portion and two forwardly open concentric channeled portions surrounding said tubular portion, the said body part having an air chamber connected to both of the said channels; a material nozzle having a shank socketed in the bore of the said tubular portion and having a larger diametered nozzle portion seating against an annular portion of said body part between the two concentric channels, the said nozzle having longitudinal air passages leading from the channel of the inner of said channeled portions; and an air nozzle member fitted upon the material nozzle and having air passages disposed for receiving air from the channel of the outer of said channeled portions.

11. In a spray gun, a gun body comprising a forward portion having a forward opening bored part, a forward opening channeled part surrounding said bored part to provide a channel therebetween, and provided with an air supply passage communicating with the channel of the channeled part, said channeled part having a rearwardly tapered annular seat, said bored part having a threaded portion and having a rearwardly tapered annular seat rearwardlyof said threaded portion; a nozzle element comprising axially spaced frusto-conical and rearwardly tapered seating portions respectively seating on said seats of saidchanneled and bored parts, and having intermediately said frusto-conical portions a threaded portion for engagement with the threaded portion of said bored part to coaxially seat said tapered portions, said nozzle element being provided with a material passage leading from said bored part and air passages leading from said channeled part, said seating portions being in a common conical surface.

12. In a spray gun as characterized in claim 1l, and in which the nozzle element has a forwardly tapered portion, a side port air nozzle member having a rearwardly flared portion formed to seat upon said forwardly tapered portion of said nozzle element, and a retainer connected to said air nozzle member and tothe forward Aportion of said gun body for seating said air nozzle member on said forwardly tapered lportion of said nozzle element.

13. A spray gun as specied in claimv 10, in which said material nozzle has a rearwardly open annular groove which communicates with said longitudinal air passages and also with the channel of the inner of said channeled portions for direct passage of air.

SVEND BRAMSEN. FRED W. WAHLIN.

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