US3670967A

US3670967A - Sanitary spray gun

Info

Publication number: US3670967A
Application number: US123134A
Authority: US
Inventors: James R Fahlin; Gerald D Hagfors
Original assignee: Graco Inc
Current assignee: Graco Inc
Priority date: 1971-03-11
Filing date: 1971-03-11
Publication date: 1972-06-20
Anticipated expiration: 1989-06-20
Also published as: JPS5635250Y2; JPS5595864U

Abstract

An airless sanitary spray gun which can be easily disassembled by hand. The fluid outlet housing of the gun has a valve to normally block the flow of fluid. Mounted on this housing is another housing designating the valve actuating housing. The device to join these two housings may consist of two locking members. One is a rotatable rod and groove combination wherein the rod extends through an opening in the valve actuating housing and is rotated to a locking position by engaging a groove in the top of the outlet housing. The other device, used to prevent rotation of the two housings relative to each other, may be one or more pins in the lower portion of the valve actuating housing with each pin engaging a notch in the upper portion of the outlet housing. Two types of valves are also disclosed. One embodiment is a small apertured spring biased needle type used for fine spraying operations. The other valve is a larger apertured dispensing type biased by a remote spring that utilizes a forced differential pressure principle to aid in keeping the valve seat seated. The gun may have its valve actuated either manually or automatically.

Description

United States Patent Fahlin et al.

[451 June 20, 1972 [54] SANITARY SPRAY GUN [72] Inventors: James R. Fahlin, Bloomington; Gerald D.

Hagiors, Columbia Heights, both of Minn.

[73] Assignee: Graco Inc., Minneapolis, Minn.

[22] Filed: March 11, 1971 [21] Appl. No.: 123,134

Primary Examiner- M. Henson Wood, Jr. Assistant Examiner-Thomas C. Culp, Jr. Attorney-Thomas Zack ABSTRACT An airless sanitary spray gun which can be easily disassembled by hand. The fluid outlet housing of the gun has a valve to normally block the flow of fluid. Mounted on this housing is another housing designating the valve actuating housing. The device to join these two housings may consist of two locking members. One is a rotatable rod and groove combination wherein the rod extends through an opening in the valve actuating housing and is rotated to a locking position by engaging a groove in the top of the outlet housing. The other device, used to prevent rotation of the two housings relative to each other, may be one or more pins in the lower portion of the valve actuating housing with each pin engaging a notch in the upper portion of the outlet housing. Two types of valves are also disclosed. One embodiment is a small apertured spring biased needle type used for fine spraying operations. The other valve is a larger apertured dispensing type biased by a remote spring that utilizes a forced differential pressure principle to aid in keeping the valve seat seated. The gun may have its valve actuated either manually or automatically.

10 Claims, 8 Drawing Figures PATENTEDJUHZO m2 3, 670,967 sum 10F 3 A k 711/ 14/4 ll F 3 m/ VE/V TORS James R. Fab/in Gerald D.Hagfors PATENTEnJlmzo m2 SHEET 2 OF 3 INVENTORS James R. Fab/in Gerald D. Hg g fors AT oRA/EY PATENTEnJunzo m2 SHEET 3 UP 3 SANITARY SPRAY GUN BACKGROUND OF THE INVENTION l Field of the Invention Generally, this invention relates to a spray gun assembly used in the fluid handling art. More specifically, it relates to a sanitary spray gun used to dispense edible fluids that is easily disassembled for cleaning purposes.

2. Description of the Prior Art Sanitary spray guns that can be disassembled are known in the art. As such guns must be disassembled on a frequent basis for cleaning purposes, their ease of disassembling is critical to their practical worth. None of the known prior art guns can be as easily and quickly disassembled entirely by hand with as few parts as our invention.

SUMMARY OF THE INVENTION The sanitary spray gun of this invention has an elongated inlet housing with an interior fluid conduit connected to an outlet housing with a fluid conduit in which a normally closed valve is placed. Mounted on the outlet housing and valve is the valve actuating housing with a cylindrical opening completely therethrough. Two types of devices may be used to maintain the outlet and valve actuating housings in place relative to each other. One prevents rotation of the housings relative to each other and the other, a rotatable rod device, is inserted in the opening of the valve actuating housing to lock the housings from pulling away from each other.

FIG. 1 shows an exploded view of the preferred embodiment of the invention with a manually actuatable valve handle.

FIG. 2 shows a side view of the gun of FIG. 1 in assembled fonn.

FIG. 3, taken along line 3-3 of FIG. 2, shows a cross-sectional view of the internal assembly of the gun.

FIG. 4 is a view of the device used to lock the valve actuating and outlet housings together.

FIG. 5 is a cross-sectional view along line 5--5 of FIG. 4 to show the locking rod.

FIG. 6 is an end view of the locking rod.

FIG. 7 is another embodiment of the valve actuating device used for automatically dispensing fluids.

FIG. 8 is a cross-sectional view taken on lines 8-,8 of FIG. 7 to show an embodiment of the dispensing valve in its seated position.

FIG. 1 shows the preferred embodiment of our spray gun invention in an exploded disassembled view. The basic stainless steel housing 1 is made up of two substantially

perpendicular housings

2 and 3 with internal cylindrical intersecting bores fabricated in one housing of stainless steel. Housing 2 is the inlet housing and has a threaded end with a union nut (not shown) to connect the gun to an external pressurized fluid supply source. Housing 3 is the outlet housing which is in fluid communication with the supply source by way of the internal intersecting bores. The threaded end 47 of housing 3 has a union nut 8 to connect the outlet nozzle assembly 9 to the housing. Mounted on outlet housing 3 is the disengageable valve actuating housing 4. When assembled, this housing 4 has a rotatable rod 7 inserted through a cylindrical opening 21 extending its entire width. Lever 5 is manually actuated by a downward counter-clockwise movement on its free end. This causes a pivotal motion around pin 6 and a lifting of the end of valve connected to the opposite end of lever 5. The normally blocked valve would then dispense a fluid out of nozzle assembly 9.

In FIG. 2 the exploded disassembled gun of FIG. 1 is shown in its assembled condition. The pivot pin 6 extends through an aperture 56 in handle or lever 5 and through hole 24 in housing 4. To prevent pin 6 from being disengaged, some type of readily removable locking member, such as hairpin 11, is attached to one end. The top part of handle 5 has an upwardly opened forked member that engages a small circular groove next to and inwardly from the nob 27 at the end of valve 10.

This allows the valve 10 to be pulled to the lefi as viewed in FIG. 2 when lever or handle 5 is depressed to the right in a counterclockwise direction around pivot pin 6. Rod 7 is correctly placed in aperture 21, as will be detailed hereinafter, to engage circular groove 12 on outlet housing 3 and lock housing 4 to housing 3. Packing gland 13 encircles a longitudinal portion of the rod portion of valve 10 in a slidable sealing manner to allow movement of the valve rod therethrough and at the same time perform a sealing function. The nozzle assembly 9 is locked in place when hand tight union nut 8 has its interior threads screwed on to threads 47 of outlet housing 3.

FIG. 3 shows in cross-section how the spray valve 10 is seated when in a blocking position within outlet housing 3. Valve 10 is one of several types of valves which can be used in our invention. It is a fine spray needle type of valve that is normally biased to the right (FIG. 3) into a blocking position by a spring 28 which encircles the rod of valve 10. This spring is held between gland 13 and stop member 30. The valve end 29 is spherically shaped and seated in the base of the Vee or inverted cone-shaped interior section of housing 3 to block the flow of fluid through conduit 48 in noule assembly 9. Gland 13 is made of an inert non-toxic material such as nylon or Teflon and acts as a seal when its surface 34 is pressed against the complementary interior surface of housing 3 as shown in FIG. 3. An elastomeric material like neoprene rubber fonns 0 ring 49 which may be placed around the outside of the gland to provide an additional sealing effect. The slideable movement of valve 10 through gland 13 to the left unblocks passage 48 to allow the spraying of fluid from inlet housing 2 out of nozzle tip 33.

FIGS. 4-6 show in greater detail the locking mechanism used to lock valve actuating housing 4 to outlet housing 3. Two locking devices are used. One consists of rod 7 which is inserted into cylindrical opening 21 with its end surface 20 on leg 16 (FIG. 6) parallel to the surface 26 (FIG. 4). Rod 7 consists of two

leg members

15 and 16. For convenience and ease in manufacturing, blocking portion 26 is formed by part of pin 22 which extends through housing 4 to partially block an end sector of the cylindrical opening 21. Surface 20 is pushed past portion 26 and then rod 7 is rotated l by manually moving its external leg member 15 to a locking position. The end of leg 15 has a small protrusion or projection 17 which when rotated engages an indentation 23 (See FIG. 1) in housing 3 to prevent further rotation of rod 7. As leg member 16 or rod 7 first pases into opening 21, its flatten cut-out surface 19 (FIG. 5) is facing towards the groove 12 in housing 3. Thereafter, when rod 7 is rotated into a locking position, semi-circular rod surface 18 is facing and engaging the groove 12 which is semi-circular in cross-section. This locks housing 3 and housing 4 to prevent them from being pulled away from each other.

The other locking device is used to prevent rotation of housing 3 relative to housing 4. In the drawings it is shown as being made up of a pin 22 that, as already mentioned, partially blocks opening 21. Further, a notch 14 (FIG. 4) on the upper portion of housing 3 is engaged by pin 22 to lock these two housings from rotating relative to each other. It is evident that more than one such pin and notch combination may be employed to prevent rotation. As an alternative, the pin and notch combination may be eliminated entirely by not extending the semi-circular groove 12 a full 360 around the upper part of housing 3. For example, if groove 12 has its semi-circular cross sectional portion only at the sector where surface 18 of rod 7 engaged it, rotation would not be possible. The reason groove 12 is a full 360 around the top longitudinal extent of housing 3 is its ease in machining.

It should be clear that the initial orientation of rod 7 is critical to its locking function. If surface 20 is not parallel to surface 26, rod leg 16 will not be able to be pushed completely through opening 21 but will be blocked by surface 26. Rod 7 could then fall out of opening 21 when housing 4 is tilted. However, if surface 20 is parallel to surface 26, rod 7 may have its end portion with surface 20 pushed past member 26.

A 360 groove 50 (FIG. 4) of the proper depth then is aligned with member 26 to allow free rotation of rod 7. It should be equally evident that the parallel alignment of

surfaces

20 and 26 is required before rod 7 can be pulled out after it is properly inserted. The cut out flatten portion 19 (FIG. 5) of leg 16 is a planar surface that extends at least half way through the diameter of leg 16. Its longitudinal extent is more than half that of the length of leg 16 and its surface is generally parallel to surface 20. Its purpose is to allow disengageability of the two locked housings 3 and 4 without removing the rod 7 when surface 19 is faced toward groove 12. The

rod legs

15 and 16 are rigidly attached to each other in a substantially perpendicular fashion along their joined longitudinal center lines when viewed from the side.

The spray gun so far described in FIGS. 1-6 is a hand held manually actuated fine spray type generally used to spray food products. Examples of its use include the spraying of liquid sugar coatings on fruit pies, the spraying of glazing compounds on pastries, etc. It should be perfectly clear that this main intended use of our invention is not its only use. Other fluid products such as paint products, adhesives, oils, and grease could, of course, also be used. In fact, any fluid could be sprayed with our invention by properly choosing the materials used for the packaging glands and sealings. The important characteristic of our invention not being the product dispensed but the ease of disassembling our spray gun.

The nozzle assembly 9 cooperates with the outlet housing 3 to form a tight frictional fit when inserted therein. As best shown in FIG. 3 assembly 9 has an inclined surface which engages a complementary surface in the interior bore of the housing 3. Forward of this engagement a large elastomer or neoprene rubber ring acts as a seal to further increase the frictional fitting. Union nut 8 when threaded on threads 47 contacts the annular flange on assembly 9 which is of the greatest diameter. This contact is made with an overlapping interior annular flange (FIG. 3) on nut 8 to aid in holding the nozzle assembly to the housing 3. The nozzle tip 3 is itself threadly held to the noule assembly 9 by a smaller nut 51. No tools are necessary to disassemble the hand

tight nuts

8 and 51.

I To completely disassemble the assembled spray gun of FIG. 2 by hand, the hairpin 11 is first pulled free of the end of pin 6. Pin 6 is then pulled out of its opening and handle is pulled downwardly and slightly to the left as viewed from FIG. 2 to free the manual actuating device. The next step is to rotate the externally shown leg 15 of rod 7 180 after pulling pin 17 from its resting indentation 23. Rod 7 may then be pulled toward the user completely out of the opening 21 or it may be just rotated to a position where surfaces 26 and are parallel. In either case, housing 4 may be simply lifted (moved to the left in FIG. 2) from outlet housing 3. If the nut holding inlet housing 2 to the fluid source had not initially been disconnected, it may now be done so. Nut 8 may now be unthreaded and valve assembly 10 pushed at end 27 downwardly (to the right in FIGS. 2 and 3) and pulled out. If a further breakdown is required, nut 51 may be unthreaded and nozzle tip 33 better exposed for cleaning. After cleaning, the gun is reassembled in reverse order.

FIGS. 7 and 8 show an additional embodiment of the gun disclosed in FIGS. 1-6. The same numbers are used to illustrate the same parts common to both embodiments. The FIG. 7 assembly embodies our invention with an automatic valve actuating device 42 in place of the manual device of FIG. 1. A source of controlled pressurized pulsating air is connected to threaded conduit 45. A passageway from inlet 45 leads to the lower surface of annular plate 53. The pressurized air forces piston 53 to the left, as viewed in FIG. 7, against the right biasing action of spring 52. This results in the left movement of plunger assembly 43 and its attached valve 36. Liquid is then dispensed from the inlet end 55 out of the outlet end 39 (FIG. 8). After each burst of air, spring 52 acts to bias valve 36 (right in FIG. 7) into its nonnally closed position. Shaft 46 is rigidly attached to the top of the actuating assembly 42 and serves as a device to adjust the force exerted by spring 52 on piston 53 by rotating the sleeve 54in its threaded connection. Rod 44 is used to adjustably attach the automatic dispensing mechanism and gun to a stationary rod located above the objects that are to have fluids dispensed thereon.

The particular valve 36 used in the gun illustrated in FIG. 7 is more clearly shown in FIG. 8 by the sectional view taken along line 8-8 of FIG. 7. This valve difiers in several material ways from the needle type valve of FIG. 3. It is first noted that no spring is employed internally of the outlet housing in the fluid flow path of the fluid to be dispensed. The remote spring 52 accomplishes this biasing function by normally forcing valve 36 to the right blocking position as shown in FIG. 8. Additional closing force is obtained when pressurized fluid impinges against the annular flanged surface 38 on the top of the valve end 37. The nozzle assembly 39 has an axial cylindrical bore to act as the fluid conduit. On the upper (or left) side of this bore an annular ridge is formed to engage the annular sides 41 of valve end 37. This forms a sufficient sealing action to prevent the unwanted flow of fluids. At the other end of valve 36 in housing 3 a seal is formed by an 0 ring and the mating of complementary surfaces as described with respect to

members

49 and 34, respectively, of FIG. 3. The end 40 of valve 36 is slideably inserted in a cut-out portion of plunger end 43 to provide transmission of the plunger's reciprocating movement to the valve.

Like the gun embodiment of FIGS. 1-6, a rotatably rod 7 and a pin and notch combination is used to lock the automatic valveactuating housing 42 to the outlet housing 3 in FIG. 7. A union nut 8 is also used to hold the dispensing inert non-toxic valve seat 39 in place. Unlike the small spray conduit 48 (FIG. 3), a larger outlet conduit is provided to dispense larger amounts of fluid on each actuation of the valve. The type, however, of valve and nozzle assembly used with the automatic valve actuating device could be the same as that described in FIG. 3. Conversely, the valve and nozzle assembly of FIG. 8 could be used in the manually actuated gun of FIG. 2. Furthermore, the type of device used to automatically actuate the valve need not necessarily be as is shown in FIG. 7. It could be powered by an electric or gas driven engine in place of the disclosed pulsating air source. The important thing is that the power source reciprocate the valve against some biasing force to allow dispensing of fluids into bottles, containers, or on to objects as they pass below it at a moving rate coordinated to the reciprocation of the valve opening.

It is thus seen that we have invented a gun that is easily manually disassembled. Health department regulations req uiring periodic cleaning of all parts exposed to the fluid flow of the discharged fluid can thus be easily satisfied. Byusing inert, non-toxic, and non-corrosive materialsfor the parts in contact with the fluid, the danger of contamination is greatly reduced. For example, the housings, nuts, and other metallic parts could be made from the 300 series of stainless steel and the 0 rings of neoprene rubber. The bearing and glands could be made of nylon or Teflon.

It will be apparent to those skilled in the art that various valve assemblies and valve actuating assemblies plus other changes may be made in my invention without departing from the spirit and scope thereof. The particular uses listed for the spray gun should not be construed as being limited by their enumeration. Therefore, our invention should not be limited by that which is shown in the drawings and described in the specification, but only as indicated in the scope of the appended claim.

We claim: 7

1. A sanitary valve gun comprising: an inlet fluid conduit means having a housing;

an outlet fluid conduit housing means having an outlet and being connected to and in fluid communication with the inlet conduit means;

a valve means within the outlet housing conduit normally blocking the passage of fluid to the outlet;

a disengageable valve actuating housing mounted on said outlet housing at the end opposite the fluid outlet, the housing having an opening therethrough and means to prevent rotation of the disengageable housing relative to the outlet housing; and

rotatable rod means slidably insertable within the housing opening to lock the disengageable housing on the outlet housing from pulling away therefrom.

2. The gun of claim 1 wherein the outlet housing has a groove on its upper end to receive in a locking relationship the rod inserted in the valve actuating housing opening when the rod is properly rotated.

3. The gun of claim 2 wherein the rod has a cross-sectional ortion which is semi-circular on one side and planar on the other, the groove in the outlet housing being semi-circular and complementary in shape to the semi-circular portion of the rod whereby the outlet housing is locked to the valve actuating housing when the semi-circular rod portion is within the semicircular groove.

4. The gun of claim 3 wherein the means to prevent rotation between the disengageable housing and the outlet housing comprises a pin member rigidly attached to the disengageable housing and a notch in the outlet housing to receive the pin.

5. The gun of claim 1 wherein the rotatable rod comprises a first and second member rigidly attached and substantially perpendicular to each other with the first member being external to the disengageable housing when the second member is inserted in the disengageable housing opening.

6. The gun of claim 5 wherein the disengageable housing has means to engage the first member of the rod and lock it against further rotation.

7. The gun of claim 1 wherein the valve means comprises a spring biased needle valve and a sanitary seal with the spring downwardly biasing the valve to cause the needle valve to block fluid flow, and the spring being between the seal and the end of the needle valve which blocks the fluid flow.

8. The gun of claim 7 including an apertured end cap removably connected to the outlet housing with a vee-shaped groove seat in cross-section therein to engage the end of the needle valve to block the aperture and thereby block fluid flow.

9. The gun of claim 1 including automatic actuating means to actuate the valve means and automatically discharge fluid from the gun outlet.

10. The gun of claim 9 wherein the valve means consists of a biased pressure difierential valve with a biasing means, the biasing means not being in the flow path of the fluid which is discharged.

Claims

1. A sanitary valve gun comprising: an inlet fluid conduit means having a housing; an outlet fluid conduit housing means having an outlet and being connected to and in fluid communication with the inlet conduit means; a valve means within the outlet housing conduit normally blocking the passage of fluid to the outlet; a disengageable valve actuating housing mounted on said outlet housing at the end opposite the fluid outlet, the housing having an opening therethrough and means to prevent rotation of the disengageable housing relative to the outlet housing; and rotatable rod means slidably insertable within the housing opening to lock the disengageable housing on the outlet housing from pulling away therefrom.

3. The gun of claim 2 wherein the rod has a cross-sectional portion which is semi-circular on one side and planar on the other, the groove in the outlet housing being semi-circular and complementary in shape to the semi-circular portion of the rod whereby the outlet housing is locked to the valve actuating housing when the semi-circular rod portion is within the semi-circular groove.

10. The gun of claim 9 wherein the valve means consists of a biased pressure differential valve with a biasing means, the biasing means not being in the flow path of the fluid which is discharged.