US2177851A

US2177851A - Coating material spray device

Info

Publication number: US2177851A
Application number: US153167A
Authority: US
Inventors: David A Wallace
Original assignee: Chrysler Corp
Current assignee: Old Carco LLC
Priority date: 1937-07-12
Filing date: 1937-07-12
Publication date: 1939-10-31
Anticipated expiration: 1956-10-31

Description

Oct. 9- D. A. WALLACE COATING MATERIAL SPRAY DEVICE Filed July 12, 1937 NAXM 1% WM, Aw m 0 m,

Patented Oct. 31, 1939 UNITED STATES PATENT OFFICE COATING MATERIAL SPRAY DEVICE Application July 12, 1937, Serial No. 153,167

10 Claims.

This invention relates to improved coating material spray apparatus.

More particularly, the invention relates to coating material of spray devices of the type from which atomized surface coating material is discharged in a finely divided state.

One of the main objects of the invention is the provision of a rotating nozzle in a spray device of this character, by which the spray discharge pattern may, in effect, be rotated.

Another object of the invention is the provision of a nozzle of this character from which air may be discharged both for the purpose of atomizing the surface coating material and bringing the discharge of the latter to a predetermined pattern.

A further object of the invention is the provision of a spray device of this kind having a rotatable air nozzle provided with spaced outlets from which air currentsmay be so directed upon a discharged stream of coating material as to flatten the coating material discharge progressively in successively different directions in order to produce the effect of a. rotating flattened discharged pattern.

Other objects of the invention are the provision of improved means, in a spray device of this character, for rotating the nozzle thereof; to provide fluid pressure operable means of this kind which may be supplied with fluid under pressure from the air passage of the normal spray device, or from an external independent course as desired; to provide an anti-friction rotative bearing structure for rotatably supporting the nozzle which is adapted to maintain the latter in concentric relationship with respect to the surface coating material discharge tube thereof; and to provide valve mechanism for simultaneously controlling the discharge of surface coating material and the supply of air to the nozzle and the supply of air to the mechanism by which the nozzle is drivingly rotated.

Fig. 1 is a side elevational view, partly in sec-- tion, of a spray gun embodying the invention.

Fig. 2 is a transverse, vertical sectional view, taken on the line 2-2 of Fig. 1.

Fig. 3 is a transverse, vertical sectional view, taken on the line 3-3 of Fig. 1.

50 Fig. 4 is a side elevational view of part of the structure shown in section in Fig. 3.

Fig. 5 is a fragmentary, front end elevational view of the spray gun, as viewed from the plane designated by the line 5--5 in Fig. 1, and diagrammatically illustrating the spray pattern and its rotative path of movement produced by the spray gun.

In the form of the invention illustrated in the drawing, the spray device comprises a main body portion, generally designated by the numeral II], which conforms substantially to gun contour. The body portion I0 includes a handle part II and a discharge part I2, angularly disposed with respect thereto. While the invention is disclosed in connection with a manually manipulatable device, it should be understood that substantially all the advantages thereof, and in some instances greater advantages, are obtainable by employment thereof on an automatic or mechanically operated spraying device.

Extending continuously through the handle part I I and discharge part I2 of the spray gun, is an air passage I3 to which compressed air may be supplied by a conduit, detachably connected to the lower end portion of the handle part II, as viewed in Fig. l. The outlet end I5 of the air passage I3 communicates with an air chamber I6 located at the discharge end portion of the device. The passage of air under pressure through the passage I3 may be controlled by Valve mechanism, generally designated by the numeral I! which is mounted on the upper end portion of the handle part I I and which includes a cylindrical bore I8 in which a piston I9 is slidably mounted. The piston I9 is secured to a stem 20 having an external end portion suitably attached to a trigger 2I which is pivotally mounted at 22 on the discharge part of the spray gun.

The valve bore I8 intersects the passage I3 and the piston I9 is adapted to close the same to prevent the flow of air from the handle part II of the gun to the discharge part I2 thereof. The left end portion of the discharge part I2 of the gun is provided with a coating material passage 23 through which the valve stem 24 extends. The valve stem 24 is slidably mounted in a gland nut structure 25 andis operatively connected with the trigger 2I in order to facilitate simultaneous operation of the valves ll and 24, respectively.

Provided on the right extremity of the discharge part I2 of the body portion of the gun is a coating material discharge tube 26 having a frusto-conical end portion 21 and an open extremity 28 which is adapted to be closed by the tapered extremity 29 on the valve stem 24, when the valve stem is in its rightward-most position. Suitable resilient means, not shown, may be employed for yieldably urging the valve stem 24 toward its closed position.

Threaded at 30 on the right extremity of the discharge part [2 of the body portion of the gun, is a collar 3! having an end portion 32 extending outwardly and serving as the peripheral wall of the compressed air chamber iii. A ring 33, provided with external threads 34, is mounted on the outer periphery of the collar 3| and located in substantially radial alignment with the portion of the body portion part of the gun on which the collar 3i is threaded. A casing, generally designated by the numeral 35, is screw-threaded on the thread 3% of the ring and provided with a cylindrical part 36 which substantially surrounds the discharge tube 26. The casing 35 has an inwardly extending lip 3? on its right extremity, as viewed in Fig. 1, within which is confined a race member 58 of a rolling contact element having a series of ball bearings 39 and an inner race member 40.

A hollow nozzle structure M is rotatably supported by the inner race member Ml and held thereby, substantially in concentric relationship with respect to the coating discharge tube 26. The nozzle ii has a central recess 42 on its inner end having an open extremity and substantially diametrically opposite lugs 33 on its outer end. Between the recesses 42 and the inner end portions of the lugs 53 is provided a relatively thin wall structure M having a central opening 45 in which he outer reduced extremity of the coating material discharge tube as is received. The central opening 45 is slightly larger than the outer diameter of the reduced end portion of the discharge tube 25 in order to provide a substantially circular slot it around the outlet end portion of the discharge tube 2'5. Formed in the transverse wall structure M are inclined air passages 61 which converge rightwardly, as viewed in Fig. 1, toward the course of the discharge from the tube 26. Formed in the annular Well portion 48 of the nozzle ll are a pair of diametrically opposite air passages d9 which extend through the lugs 43 and which have inwardly converging discharge end portions 58 so arranged as to direct blasts of air from respectively opposite directions upon the coating material discharged from the tube 26. The slot 56, inclined air passages 47, and outer air passages 45 all communicate with the air chamber it during all positions of the nozzles relative to the body portion of the spray device during rotation of the nozzle.

A ring having an axially extending flange 5! is non-rotatably secured to the left end portion of the nozzle 45 and disposed in a chamber 52 located between the side planes of the race members 33 and l!) and the outer side face of the threaded ring 33. Provided on the left side face of the flange 5! is a series of vane elements 53 by which the flange and nozzle ll attached thereto are adapted to be rotated. The ring 33 is provided with a peripheral groove 5 2 from which extend air passages 55 having outlet end portions communicating with the air chamber 52 and arranged so as to direct jets of air upon the vanes 53, the air being exhausted to atmosphere through slots 33 in the casing 35. The peripheral groove 54 is supplied with air, or other suitable fluid under pressure, through a fitting 56 mounted on the casing 35 and having a passage 51 leading to the peripheral groove 54. The outlet end portions of the air passages 55 are so directed as to rotate the ring 59' and nozzle 4! fixed thereto in a predetermined direction.

In the form of the invention illustrated in the drawing, the fitting 56 is connected by a flexible coupling 58 with an elbow-shaped fitting 59 threaded in the main body portion of the spray device and having a passage therein which communicates with the air passage l3 of the latter. In this form of the invention, the air current which is utilized to rotate the spray nozzle 4! is derived from the same source as the air which is supplied to the nozzle of the spraying device. If it is desired to supply air to the vanes 53 under a pressure or by a fluid medium different from that of the passage I3, the fitting 56 may be connected with any suitable source of fluid pressure (not shown).

The coating material is supplied to the interior of the passage 23 and to the discharge tube 26 by a conduit 66 which is connected with a fitting 6! having a passage 62 therethrough leading to the passage 23. In the device shown in the drawing, the air supplied to the vanes, as well as that supplied to the nozzle may be controlled by the trigger 2! simultaneously with control of the discharge of coating material from the tube 26.

In the operation of the foregoing paint spray device, when the trigger 2i is moved in a clockwise direction from the position shown in Fig. 1, paint is discharged from the discharge tube 25 and a current of air is discharged through the circular slot $8 to atomize the coating material as it leaves the tube 26. Air supplied through the inner pair of converging and oppositely directed air passages 41 also aids to some extent in the atomizing of the discharge of the coating material. The streams of air discharged through the passages 41, however, together with the air streams discharged from the passages 49, flatten the stream of coating material discharged so as to produce the elongated spray pattern illustrated at 63 in Fig. 5. Since these inclined and converging air streams rotate in unison with the nozzle, they progressively flatten the coating material discharge from successively angularly changed positions so as to, in effect, cause the spray patterns 63 to rotate about the axis of the nozzle 4| and about the axis of the discharge tube 26 which is substantially concentric therewith. In this manner, the effective spread of the spray discharge pattern is materially increased and the distribution of the coating material upon the surface to which it is applied is correspondingly improved. Less manual movement of the gun is required on the part of the workman and the hazard of building up excessive thicknesses of coating material at isolated portions of the surface being sprayed, by unintended hesitation of the workman during manipulation of the spray gun is greatly reduced.

Although but one specific embodiment of the invention is herein shown and described, it will be understood that various changes in the size, shape and arrangement of parts may be made without departing from the spirit of my invention.

What I claim is:

1. A coating material spraying device comprising a main body portion having passages therein for conveying coating material and air under pressure respectively, a nozzle rotatably mounted on said main body portion having a coating material outlet and having a pair of air passages communicating with the air passage of said main body portion and provided with opposed air discharge orifices located in spaced relation to and directed toward the axis of rotation of said nozzle in externally converging relation with respect thereto and revolvable about said axis, and means for drivingly rotating said nozzle whereby said orifices are revolved during operation of said spraying device. i I

2. A coating material spraying device comprising a main body portion having passages therein for conveying coating material and air under pressure respectively, a nozzle rotatably mounted on said main body portion having a coating material outlet adjacent its axis of rotation and having a pair of air passages communicating with the air passage of said main body portion and provided with air discharge orifices located on opposite sides of said outlet and directed in converging relation toward the path of discharge of and located outwardly from said coating material outlet and revolvable about the latter, means on said nozzle responsive to a fluid pressure discharge for drivingly rotating said nozzle, and a fluid pressure discharge member having an outlet adjacent said means.

3. A coating material spraying device comprising a main body portion having passages therein for conveying air under pressure and coating material respectively, a coating material discharge tube communicating with said coating material passage and having an outlet orifice for discharging a stream of coating material from said device directly in advance thereof, a nozzle rotatably mounted on said main body portion substantially in concentric relationship with respect to the outlet of said discharge tube and provided with air passages having inlet ends communicating with the air passage of said main body portion and outlet ends radially spaced from the rotative axis of said nozzle and so constructed and arranged as to discharge air into said stream of coating material at a location externally of said nozzle, and means for drivingly rotating said nozzle during operation of said spraying device.

4. A coating material spraying device comprising a main body portion having passages therein for conveying air under pressure and coating material respectively, a coating material discharge tube communicating with said coating material passage, a nozzle rotatably mounted on said main body portion substantially in concentric relationship with respect to the outlet of said discharge tube and provided with air passages having inlet ends communicating with the air passage of said main body portion and outlet ends radially spaced at diverse distances from the rotative axis of said nozzle, the outlet end portions of said nozzle air passages being inclined with respect to said rotative axis and to the course of coating material discharge from said tube for directing blasts of air in converging relationship upon said coating material discharge, and means for drivingly rotating said nozzle during operation of said spray device.

5. A coating material spraying device comprising a main body portion having passages therein for conveying air under pressure and coating material respectively, a coating material discharge tube communicating with said coating material passage having an outlet for discharging coating material externally of said device, a nozzle rotatably mounted on said main body portion substantially in concentric relationship with respect to the outlet of said discharge tube, said rotatable nozzle being provided with a plurality of air passages communicating with the air passage of said main body portion and having outlet end portions so directed with respect to the discharge of coating material from said tube as to converge with said coating material discharge at a location externally of said device and to maintain said discharge in a predetermined rotating non-circular pattern during rotation of said nozzle, andmeans for drivingly rotating said nozzle.

6. A coating material spraying device comprising a main body portion having passages therein for conveying coating material and air under pressure respectively, a nozzle rotatably mounted on said main body portion having a coating material outlet for discharging a stream of coating material externally of said device and having a pair of air passages rotatable in unison with said nozzle and communicating with the air passage of said main body portion and provided with opposed outlet orifices for discharging streams of air from opposite directions upon said coating material discharge at a location externally of said device. air propellable vanes on said nozzle, means communicating with the air passage of said main body portion and adapted to direct a discharge of air on said vanes for drivingly rotating said nozzle during operation of said spraying device, and valve mechanism in the air passage of said main body portion for simultaneously controlling the supply of air tothe air passages of said nozzle and to the vanes thereof.

7. A coating material spraying device comprising a main body portion having passages therein for conveying air under pressure and coating material respectively, a coating material discharge tube communicating with said coating material passage, a nozzle rotatably mounted on said main body portion substantially in concentric relationship with respect to the outlet of said discharge tube and provided with air passages having inlet ends communicating with the air passage of said main body portion and opposed outlet ends radially spaced from and located on opposite sides of the outlet of said discharge tube for discharging substantially oppositely directed air blasts upon the discharge from said tube to bring the discharge pattern to a flattened contour, fluid operable means on said nozzle for drivingly rotating the latter, and means for directing a blast of air upon said driving means.

8. A coating material spraying device including a main body portion having coating material and air passages therein, a coating material discharge tube communicating with said coating material passage and extending from one end of said spray device and having a discharge orifice in its external end, an annular casing surrounding said discharge tube, a rotatable nozzle having air passages therein communicating with the air passage of said main body portion, and having air outlets for directing streams of air against the coating material discharged from said orifice at a location externally of said device, means in said casing for rotatably supporting said nozzle, a propelling member non-rotatably fixed to said nozzle and having vane elements disposed in said casing, and means for discharging fluid under pressure into said casing and upon said vanes.

9. A coating material spraying device including a body portion, a fixed coating material discharge tube, an air discharge nozzle rotatably mounted on said body portion and surrounding the outlet end portion of said tube having air discharge outthe effect of rotating said discharge pattern is produced.

10. A coating material spraying device including a body portion, an air discharge nozzle rotatably mounted on said body portion, a fixed coating material discharge tube on said body portion having a discharge passage extending axially of said nozzle for discharging a stream of coating material in a direction generally parallel to the axis of rotation of said air nozzle, said air nozzle having a pair of opposed rotating air outlets spaced from and directed toward said axis for discharging streams of air from opposite directions in courses converging externally of said device with said stream of coating material, and means for drivingly rotating said nozzle during spraying operations.

DAVID A. WALLACE.