US2887274A

US2887274A - Spray gun for applying plaster and the like

Info

Publication number: US2887274A
Application number: US716315A
Authority: US
Inventors: Swan V Swenson
Original assignee: Individual
Current assignee: Individual
Priority date: 1958-02-20
Filing date: 1958-02-20
Publication date: 1959-05-19
Anticipated expiration: 1976-05-19

Description

May 19, 1959 s. v. SWENSON 7 2,837,274

, SPRAY GUN FOR APPLYING PLASTER AND THE LIKE Filed Feb. 20. 1958 28 2e 42 g\49 c Inuen'tbr 5 an. V- Swanson.

United States Patent SPRAY GUN FOR APPLYING I'LASTER AND THE LIKE Swan V. Swanson, Minneapolis, Minn. Application February 20, 1958, Serial No. 716,315

Claims. (Cl. 239-371) My invention relates to improvements in. spray guns, particularly such guns of the type adapted to apply plaster and the like.

In a spray gun for plaster and similar materials, it is desirable that the gun be conveniently manipulated and variably regulated by one hand of the user leaving the other hand normally free.

It is further desirable that a spray gun of the nature indicated be capable of being so adjusted in regulation of its output that any selected adjustment made may be maintained, as desired, without expenditure of effort on the part of the user.

Additionally it is importantly desirable that a spray gun of the present nature. be not onlysimple, durable and inexpensive in construction. and efficient in operation, but that it be adapted to be quickly and easily dismantled to an extent rendering the parts thereof capable of being readily washed clean of the plaster or other material accumulating thereon in use, and that the parts may be quickly and easily reassembled for subsequent use. of the gun.

It is an object of my invention to provide a spray gun constructed in attainment of the various: desiderata aforesaid.

J Other objects of the invention reside in the novel combination and arrangement of parts and in the details of construction hereinafter illustrated and/or described.

In the drawing:

Fig. l is a side elevational view of a spray gun constructed in accordance with my invention, portions of. the: structure being broken away to reveal otherwise concealed construction.

Fig. 2 is a fragmentary front elevational view of said spray gun.

t Fig. 3 is a fragmentary rear elevational view of said spray gun.

Fig. 4 is a transverse sectional view taken as on the line4-4 of Fig. 1, portions of the structure being broken away to disclose internal construction of some of the parts. a

Reference being had to the illustrated form of my invention, it will be seen that it includes a body A having a'chamber it} therein and a handle 11, like that of a pistol, depending from said body A. At the top of the body A isan: annular flange 12 defining an opening leading into said chamber 1t Fitted into said flange 12 is the lower reduced end 13 of a hopper 14' for the supply of. material to be sprayed, said hopper 14 being provided at the top thereof with a material-retaining flange 15 to prevent the spillage of material from the hopper when the gun is tilted rearwardly, as in spraying. anelevated area. At the front of the body A is an. annular flange 16 defining an opening communicating with the chamber 10 in said body. A nozzle 17 removably fitted into the front. annular flange 16 has a peripheral flange 18 overreaching the forward face of said front flange of the body A. This nozzle flange 18 is. formed with diametrically opposed outwardly opening slots 19 receiving 'ice threaded studs 20 screwed into said body flange 16 and fitted with wing nuts 21 adapted to be turned against said nozzle flange 18 to clamp said nozzle 17 in place within said front flange 16 of the body A. The nozzle 17 is formed with a discharge orifice 22 having at the rear thereof an annular valve seat 23. The gun is furnished with a number of nozzles, the discharge orifices of which vary in diameter to suit various conditions arising in usage of the device. At the rear portion of the body A is a boss 24 which extends forwardly into the chamber 10 of the body A and rearwardly to the rear of said body. This boss 24 has a bore 24 therein occupied by a bushing 25, which receives a main stem 26 of a cylindrical valve member B, said stem26 of said valve member B being longitudinally slidable and rockable in said bushing 25. The bore 24 in the boss 24 is enlarged and interiorly threaded at its rear portion, as at 24", to receive a packing nut 27 through which said main stem 26 of the valve member B extends.

The forward portion of the stem 26 of the valve membet E is conically formed, as at 28, for coaction with the valve seat 23 of the nozzle 17. Thus formed, the valve stem 26, in the foremost position of its longitudinal sliding movement, will engage said valve seat 23 and close the orifice 22 in the nozzle 17 against discharge therefrom of material introduced into the chamber 10 of the body A from the hopper 1d. Said stem 26 of said.v

valve member B is formed with an axial bore 29 into: which air under pressure is introduced, as will more fully hereinafter appear. In retracted longitudinally adjusted positions of the stem 26 of the valve member B, the discharge orifice 22 in the nozzle 17 is obstructed in greater or lesser degree by said stem whereby the flow of material from the chamber 10 of the body A is regulated, such material being impelled from said chamber 10 through the discharge orifice 22 and sprayed therefrom by the blast of air issuing from the bore 29 in said stem 26 of the valve member B. Said valve member B includes a tail piece 30 in the form of a length of pipe which is axially aligned with the valve stem 26 and coupled thereto by means of a nipple 31. At itsforward portion, this nipple 31 receives the reduced exteriorly threaded rear portion 32 of said stem 26 of the valve member B, and at its rearward portion, said nipple 31 receives the exteriorly threaded forward portion 33 of said tail pipe 30 of the valve member B. When the gun is in use, said tail pipe 30 is coupled at its rearward end to an air supply hose, as at 3 leading from any suitable source of air under pressure.

The valve member B is spring loaded and normally yieldingly held with its stem 26 in orifice-closing contact with the valve seat 23 at the inner end of the orifice 22 in the nozzle 17. Said valve member B is thus loaded by a helical expansion spring 35 encircling the coupling nipple 31 and the forward portion of the tail pipe 30 of said valve member. In reducing the end 32 of the valve stem 26 to accommodate said nipple 31, a shoulder 36 is formed on said stem. A front abutment for the spring 35 is constituted by a plate 37 which has an opening therein receiving said reduced end 32 of the valve stem. 26, said plate 37 being rigidly clamped between said shoulder 36 and the forward end of the coupling nipple.

, sion of upwardly opening notches 41 which individually receive the lower edge of the latch lever 40, upon ap-' Patented May 19, 1959 propriate longitudinal adjustment of the valve member B, and releasably secure the thus adjusted valve member B against the action of the spring 35.

In using the spray gun, an operator can apply his free hand to the latch lever 40 and employ it as a means for retracting the valve member B into any desired position of its longitudinal adjustment. Said latch lever 40, however, has for its principal purpose the latching of said valve member B in any selected position of adjustment into which said valve member may be retracted by means of a trigger D which is associated with the pistol-like handle 11. This trigger D includes a rod 42 slidably mounted in a way 43 formed at the junction of the body A and handle 11, said rod 42 being slidable relative to the body A in parallelism with the valve member B. Said trigger rod 42 has a finger piece 44 depending from its forward end in position to be engaged by the index finger of a users hand grasping the handle 11.

The plate 37, which, as aforesaid, provides an abutment on the valve member B for the forward end of the spring 35 and which has said latch lever 40 thereon, constitutes also a coupling medium between the trigger rod 42 and valve member B. A depending portion 37 of the plate 37 has an arcuate slot 45 therein formed with an enlargement 46 at the end thereof nearest to the arm 39 of the bracket C. Said slot 45 follows an arc struck from the axis of the valve member B, the radius of said are being equal in length to the distance between the axes of said valve member B and trigger rod 42. Thus, said slot 45 is intersected by the axis of said trigger rod 42, the enlargement 46 of said slot 45 being adapted to take position in axial coincidence with said trigger rod axis in one position of said coupler plate 37 in which it may be stationed. The trigger rod 42 is detachably connected to the coupler plate 37 through the medium of said slot 45, the rearward end of said rod 42 being formed with an annular groove therein providing a reduced reach 47 axially of the rod 42 and relatively

spaced shoulders

48 and 49, the former being located forwardly of the reach 47 and the latter located rearwardly thereof. Said reduced reach 47 of the trigger rod 42 is normally received within the slot 45 of the coupler plate 37 with the front shoulder 48 on said rod'42 proximately facing the forward face of the coupler plate 37 and the rear shoulder 49 on said rod proximately facing the rearward face of said plate. Upon pulling the trigger D, rearward movement of the trigger rod 42 is imparted to the valve member B retracting the same. Conversely, forward movement of the valve member B, by action of the spring 35, is imparted to said trigger rod 42, returning the trigger D, under control of the users trigger finger, to starting position wherein the valve member B closes the discharge orifice 22 in the nozzle 17. In connecting the coupler plate 37 to or disconnecting it from the trigger rod 42, the former is swung, counterclockwise as seen in Fig. 3, into position bringing the enlargement 46 of the slot 45 into axial coincidence with the axis of said trigger rod 42. With the coupler plate 37 and trigger rod 42 thus relatively disposed, the said parts may be disconnected from each other simply by shifting one thereof longitudinally relative to the other to cause the rear shoulder 49 on the trigger rod 42 to be withdrawn from the plate 37 through said enlargement 46 of the slot 45 in said plate. To connect the coupler plate 37 to the trigger rod 42, the reverse of the aforesaid operation is performed and thereafter followed by swingably returning the coupler plate 37 into position bringing the reduced reach 47 of the trigger rod 42 into the slot 45 in said plate 37. t

Disconnection of the coupler plate 37 from the trigger rod 42 is one of two steps taken in freeing the valve member B for its withdrawal from the body A to enable said valve member B and the interior of the body A and hopper 14 to be readily and thoroughly washed to clean therefrom all plaster or the like which has accumulated there- 4 on. Another step which is taken to free the valve member B for its withdrawal from the body A involves the pivoting of the forward end of the aforesaid arm 39 of said bracket C to said body A so that said arm 39 may be swung down away from said valve member B. Said forward end of said arm 39 lies against the outer face of a side extension 50 of the body A. A headed screw 51 extending through said bracket arm 39 and threaded into said extension 50 of the body A provides a pivotal bearing for said arm 39 about which the bracket C is swingable. Normally, to retain the swingable bracket C in operative disposition wherein its flange 38 provides a rear abutment medium for the spring 35, a washer 52 is employed, the same having a retainer lip 53 turned outwardly therefrom. This washer 52 fits about the tail pipe 30 of the valve member B and is normally interposed between the rear end of the spring 35 and the forward face of the abutment flange 38 of said bracket C, the retainer lip 53 in such case being in underlying engagement with the lower edge of said flange 38 in opposition to the opening of an upwardly opening notch 54 in said flange 38 in which notch 54 said tail pipe 30 is received, such engagement of said lip 53 with said flange 38 normally preventing the downward swinging of the bracket C away from the valve member B. To effect the downward swinging movement of the of the bracket C and thereby shift it out of the way of the valve B for the withdrawal of said member from the body A, the washer 52 is forced forwardly along the tail pipe 30 against the action of the spring 35 sufliciently to free the washers retainer lip 53 from the abutment flange 38 of said bracket C, whereupon said bracket will swing downwardly into position clear of said valve member B. To return the bracket C into its operative relationship with the valve member B, the reverse of said operation aforesaid is performed as will be readily understood.

When the bracket C is operatively disposed, the arm 39 thereof provides a stop limiting the downward throw of the latch lever 40 so that until the bracket C is downwardly swung away from the valve member B, the latch lever 40 is prevented from swinging downwardly sufliciently to bring the slot enlargement 46 in the coupling plate 37 into position wherein the rear shoulder 49 on the trigger rod 42 could be unintentionally withdrawn therethrough.

From the foregoing, it will be appreciated that I have provided a construction in spray guns which well meets the aforementioned objectives of my inventiona con struction which, among other things, features the convenient manipulation of the gun in one hand and the regulation of the output of the gun by the same hand; the ready releasable latching of the valve member in selected positions of its adjustment; the selection and arrangement of parts in a simple, durable and effective organization making for ease and dispatch in the limited dismantling thereof required for cleaning purposes, and making for the quick and easy replacement of parts preparatory to the resumption of use of the gun.

Changes in the specific form of the invention, as herein described, may be made within the scope of what is claimed without departing from the spirit of the invention.

Having described the invention, What is claimed as new and desired to be protected by Letters Patent is:

1. In a spray gun for applying plaster and the like, a body having a chamber therein and a material-receiving opening leading thereinto, a nozzle in the front portion of the body having a discharge orifice leading forwardly from said chamber, a cylindrical valve member mounted in the rear portion of the body in axial alignment with the axis of said orifice, said valve member being axially movable for withdrawal from and for longitudinal adjustment and rotational rocking movement relative tosaid body, said valve member coacting at its forward portion with said nozzle to close said orifice and to open the same in varying degree according to the longitudinal adjustment of said valve member, said valve member having therein an axial' passageway for the passage: of air therethrough, said" valve member being adapted to be connected at its rearward end with a flexible air line to supply said air passageway with air under pressure, a handle depending from the body, a trigger rod slidably mounted in the body in parallelism with the valve member, said rod having a finger piece depending therefrom forwardly of the handle in position accessible to the finger of a hand grasping said handle, a coupler plate fixed to the valve member transversely thereof rearwardly of the handle, a releasable key slot connection between said trigger rod and coupler plate, said connection 1ncluding a slot in said coupler plate curvedalong an arc struck from the axis of the valve member, said plate having a slot"enlarging"openingtherein at one end of said slot adapted to take position in axial coincidence with the axis of the trigger rod, the rear portion of said trigger rod having a reduced reach axially thereof and also having relatively spaced shoulders forwardly and rearwardly ofsa'id reduced reach, said slot enlarging opening being adapted to receive and accommodate the passage of said rearward shoulder therethrough, the slot being adapted to receive said reduced reach, and said shoulders being adapted to engage opposite faces of the coupler plate along said slot, a vertically swingable bracket having an arm pivoted at its forward end to said body, said arm having at its rear end an inturned abutment flange formed with an upwardly opening notch adapted to receive the rear portion of the valve member, a washer slidable along said rear portion of the valve member, said washer being normally backed against said abutment flange and having at its lower portion a rearwardly extending lip normally in underlying engagement with the lower edge of said abutment flange, a helical expansion spring encircling the valve member and interposed between said washer and said coupler plate, said spring acting yieldingly to urge the valve member forwardly into its advanced orifice closing position, a latch lever extending from the coupler plate transversely of said arm of said bracket above the upper edge thereof, said edge of said arm having a succession of upwardly opening notches therein adapted individually to receive the lower edge of said latch lever and releasably hold the valve member in given position of its longitudinal adjustment, the lip on said washer being adapted to be Withdrawn from engagement with the abutment flange on forward movement of the washer on the valve member against the action of said spring, thus to release the bracket for downward swinging movement shifting its abutment flange into position clear of the path of longitudinal movement of the valve member, said key slot connection between the coupler plate and trigger rod enabling said coupler plate to be released from said trigger rod, thereby to free the valve member for the rearward withdrawal thereof from said body.

2. A spray gun, as defined in claim 1, wherein the relationship between the key slot enlargement in the coupler plate, and the arm of the swingable bracket, is such that the latch lever, in its latching throw, engages the arm of the normally positioned bracket, and is thereby stopped short of a position assumed by said latch lever when the key slot enlargement in the coupler plate takes position in axial coincidence with the axis of the trigger rod for the detachment of said plate from said rod.

3. In a spray gun for applying plaster and the like, a body having a chamber therein and a material-receiving opening leading thereinto, a nozzle in the front portion of the body having a discharge orifice leading forwardly from said chamber, a cylindrical valve member mounted in the rear portion of the body in axial alignment with the axis of said orifice, said valve member being endwise slidable relative to the body for longitudinal ad justment of said member and for withdrawal of the same from said body, said valve member coacting: with said? nozzle to obstruct said orifice, closing or restricting it,

in varying degree depending upon the longitudinal adjustment accorded said valve member, said valve memher having therein an axial passageway for the passage of air therethrough, said valve member being adapted to be connected at its rearward end with a flexible air supply line for feeding air under pressure to said air passageway, a handle extending from the body, an arm a rearwardly extending retainer lip normally in engagement with said abutment flange at a locality in opposition to the opening of said notch therein, a helical expam sion spring encircling the valve member, an abutment on valvemember abutted by the front end of said spring, said spring at its rear end abutting said washer and acting yieldingly to urge the valve member forwardly into its advanced! orifice-closing position, a lever carried by the valve member, said lever extending outwardly from the valve member transversely of said arm, said arm having a suc cession of notches therein adapted individually to receive the latch lever and releasably hold the valve member in given position of its longitudinal adjustment, the retainer lip on said washer being adapted to be withdrawn from engagement with the abutment flange on for- Ward movement of the washer on the valve member against the action of said spring, thus to release the arm for swinging movement shifting its abutment flange into position clear of the valve member, thereby to enable said valve member to be withdrawn from said body.

4. In a spray gun for applying plaster and the like, a body having a chamber therein and a material-receiving opening leading thereinto, a nozzle in the front portion of the body having a discharge orifice leading forwardly from said chamber, a cylindrical valve member mounted in the rear portion of the body in axial alignment with the axis of said orifice and axially movable for endwise removal from and for longitudinal adjustment relative to said body, said valve member coacting at its forward portion with said nozzle to close said orifice therein and to open said orifice in varying degree according to the longitudinal adjustment of said valve member, said member having therein an axial passageway for the passage of air therethrough, said valve member being adapted to be connected at its rearward end with a flexible air supply line communicating with said air passageway, a handle depending from the body, a trigger mounted on the body, said trigger having a finger piece located forwardly of said handle and operable by a finger of the hand grasping said handle, connecting means interposed between said trigger and valve member, said means acting to shift the valve member rearwardly upon rearward movement of the trigger, a swing- Y able bracket having an arm pivoted at its forward end to said body, said arm having an abutment flange at its rear end formed with a notch therein adapted to receive the rear portion of the valve member, a helical expansion spring encircling the valve member, an abutment on the valve member engaged by the forward end of said spring, said abutment flange of said bracket providing a backing for the rear end of said spring, said spring normally serving yieldingly to urge the valve member for wardly into its advanced orifice'closing position, a latch lever extending outwardly from the valve member transversely of the arm of said bracket over the upper edge thereof, said edge of said arm having a succession of upwardly opening notches therein adapted individually to receive the lower edge of said latch lever and releasably hold the Valve member in given position of its longitudinal adjustment, the bracket being swingable on the body 7 into position clear of the'valve member, the connection between the trigger and valve member being detachable to free the valve member for the rearward withdrawal thereof from said body.

5. In a spray gun for applying plaster and the like, a body having a chamber therein and a material-receiving opening leading thereinto, a nozzle in the front portion of the body having a discharge orifice leading forwardly from said chamber, a cylindrical valve member mounted in the rear portion of the body in axial alignment with the axis of said orifice and axially movable for longitudinal adjustment relative to said body, said valve member coacting at its forward portion with said nozzle to close said orifice therein and to open said orifice in varying degree according to the longitudinal adjustment of said valve member, said valve member having therein an axial passageway for the passage of air therethrough, said valve member being adapted to be connected at its rearward end with a flexible air supply line leading to said air passageway, a handle depending from the body, a trigger mounted on the body and operable by a finger of the hand grasping said handle, connecting means inter- 8 posed between said trigger and valve member acting to shift the valve member rearwardly upon rearward movement of the trigger, anal-m extending rearwardly from the body, said arm having an abutment at the rear end thereof, a helical expansionspring encircling the valve member, an abutment on the valve member engaged by the forward end of said spring, said spring at itsrear end abutting said abutment on said arm and acting yieldingly to urge the valve member forwardly into its advanced orifice-closing position, a latch lever extending outwardly from the valve member transversely of said arm, said arm having a succession of notches therein adapted individually to, receive said latch lever and releasably hold the valve-member in a given position of its longitudinal adjustment.

References Cited in the file of this patent UNITED STATES PATENTS 633,228 Cholodkowsky Sept. 19, 1899 2,134,415 Peerstone Apr. 6, 1915 2,305,269 Moreland Dec. 15, 1942