GB2091134A

GB2091134A - Portable liquid sprayers

Info

Publication number: GB2091134A
Application number: GB8200717A
Authority: GB
Original assignee: Britt Tech Corp
Current assignee: Britt Tech Corp
Priority date: 1981-01-15
Filing date: 1982-01-11
Publication date: 1982-07-28
Also published as: LU83874A1; AU541300B2; NL8105028A; FR2497692A1; IT8150007A0; AU7850881A; DK3182A; GB2091134B; NZ198725A; PT74284A; IT1210599B; PT74284B; SE8200150L; DE3145109A1; CA1195962A

Abstract

Liquid to be sprayed is held in a container 32 mounted on an intermediate portion 14 of an elongate handle 10. When a valve 24 is open, the liquid flows under gravity through a conduit 21 to discharge into an upwardly facing cup 20 secured to the vertical drive shaft 19 of an electric motor 18 at the front end 15 of the handle 10. The valve 24 is controlled manually with a control cable 28 which also controls the opening and closing of the on/off switch of the power circuit 36,37 for the motor 18, the power source being a battery 40 mounted on the handle 10. The cup 20 has downwardly and outwardly directed holes 45 through the periphery of its bottom wall 42 so that when the motor 18 rotates the cup 20, the liquid in the cup 20 is sprayed out from these holes 45. The handle 10 can be demounted from a wheeled frame 12. The holes 45 are all the same size and the rate of flow of liquid into the cup 20 is constant. The cup 20 is rotated at a constant rate and the spray consists of uniform droplets. The container preferably has an air inlet (56), Figures 7, 8 (not shown), controlled by a pressure-sensitive valve (57) which admits air to the interior of the container at a rate dependent upon the head of liquid pressure therewithin to thereby provide a uniform flow to the valve 24. <IMAGE>

Description

SPECIFICATION Improvements in portable liquid sprayers This invention relates to portable liquid sprayers.

A preferred embodiment of the present invention is in the form of a demountable wheeled liquid sprayer comprised of an elongate handle supporting a motor with a drive shaft rotatably mounting a cup having inwardly and upwardly extending sidewalls with openings extending downwardly and outwardly therethrough around the periphery of its bottom.

The handle is detachably mounted on a two-wheeled frame and supports a removable liquid container which discharges into the cup through an associated valve. A valve control mounted on the handle simultaneously opens the valve while activating the motor, or closes the valve while deactivating the motor. The handle and sprayer may be detached, transported and used manually without the wheeled frame.

The invention will now be described in more detail, solely by way of example, with reference to the accompanying drawings, in which: Figure 1 is a schematic side elevational simplified view of a demountable wheeled liquid sprayer embodying the invention; Figure 2 is a rear elevational view thereof; Figure 3 is a side elevational view with parts broken away.

Figure 4 is a side elevational view on an enlarged scale of the distributing head, with parts broken away; Figure 5 is a sectional view taken along line 5-5 of Figure 1; Figure 6 is an auxiliary sectional view along line 6-6 of Figure 1, on an enlarged scale; Figure 7 is a schematic side elevational view of the sprayer with an improved liquid flow control; and Figure 8 is a sectional view on an enlarged scale of the flow control cap of Figure 7.

In Figure 1 there is shown a demountable wheeled liquid sprayer having a handle 10, a liquid spreader 11, and a detachable two-wheeled frame 12. The handle 10 has a tubular rear end 13, an intermediate portion 14, and an angulated lower end 15. The forward end 15 and intermediate portion 14 comprise a moulded split casing 16 secured to a tubular metal member 17.

Mounted on the forward end 15 is an electric motor 18 having a drive shaft 19 which rotatably mounts a cup 20 as shown in Figure 4. A conduit 21 discharges liquid through its discharge spout 22 into the cup 20, and includes a tube 23 which connects the spout 22 with a valve 24 which is interposed within the conduit 21, a supply pipe 30 forming the upstream part of the conduit 21.

As Figure 6 shows, the valve 24 includes a connector 25 having a valving member 26 engaging a valve seat 27 and slidable by a control cable 28 between open and closed positions. Afeed nozzle 29 extends into the supply pipe 30 which extends to the outlet 31 of a liquid container 32 which is carried by the handle 10.

The cable 28 is confined by the handle 10 and has a knob or loop 33 by which the cable 28 can be operated to move the valving member 26, and control the motor 18.

The cable 28 has a cam 34 disposed adjacent a switch 35 (Figure 6) which is mounted on the handle 10 and is interposed within an electrical circuit established by lead lines 36, 37 (Figure 1). These lead lines run between the motor 18, the switch 35, and a two volt, five ampere lead acid rechargeable battery 40, such as the X-Cell battery sold by Gates Rubber Company, Denver, Colorado, U.S.A. The battery 40 has a recharge receptacle 41. Shifting of the cable 28 and cam 34 causes the switch 35 to be opened and closed simultaneously with closing and opening of the valve, respectively.

The cup 20 is mounted coaxially upon the drive shaft 19 and has a bottom wall 42 and an upstanding side wall 43 which extends upwardly and inwardly from the bottom wall 42. A plurality of openings 45 extend downwardly and outwardly from the periphery of the wall 42 and terminate at is lower outer edge.

The container 32 is made of soft resilient plastic. It has a filler opening with a cap 46 and a thin seal which can be perforated after the container is applied to the handle 10. The container is molded with a radial slot 47 indicated in Figure 2 at its periphery which is slightly narrower than the diameter of the handle member to clamp thereon. An abutment carried by the handle abuts the container to support same.

Two wheels 48 and 49 are coaxially mounted in the frame 12. The frame 12 has a grooved receptable 50 which tapers inwardly and downwardly as shown in Figures 1 and 2. A matching tongue member 51 on the handle 10 fits thereinto and releasably connects the two. A detent 52 holds the tongue member 51 within the groove of the receptacle 50.

Figures 7 and 8 show details of a preferred container 55 which provides uniform flow into the cup whether the container is full or near empty. As shown, the upper end of the conduit 30 is applied to a discharge nozzle 53 which is part of a cap member 54 for the liquid container 55. An air inlet tube 56 has a check valve ball 57 which normally closes an air inlet 58. The container 55 has the same cross section as the container 32 and an abutment 59 supports it.

The liquid is supplied to the cup 20 uniformly as a result of the controlling effect of the pressuresensitive valve 57,58. When the container 55 is full, a heavy head of liquid pressure bears against the ball 57 and urges it toward the closed position more forcefully than when the container is relatively empty. The heavy head of pressure tends to cause the discharge through the open conduit 30 at its lower end to be more rapid, but the partial vacuum created at its upper end by the prior discharge of liquid diminishes such rapid discharge. When the difference between the air pressure outside the container and that therewithin becomes great enough to open the check valve against the liquid pressure action, air will enter through the air inlet 58 and increase the internal air pressure, thereby permitting additional flow through the discharge conduit 30.In this manner, a uniform flow is maintained, since the increase in internal air pressure counter-balances the loss of head of liquid within the container and its action upon the check valve.

A removable restrictor (not shown) having an orifice is mounted in the upper end of the discharge spout 22 and receives the lower end of the tube 23 therearound. This restrictor controls the liquid flow into the cup 20 and is replaceable by a similar member having a differently sized orifice, to facilitate supplying of a liquid having a different viscosity, orata different flow rate.

Since the rate of flow is determined by the orifice of the removable restrictor (not shown) which is mounted in the upper end of the discharge spout 22, it is not necessary for a particular flow rate that the discharge openings 45 be of the same size, or diameter, in any given cup, and their length or radial positioning with respect to the axis of the drive shaft 19 has no appreciable effect on the spray produced except that it may modify the scope of the pattern produced thereby, which may also be modified by the speed at which the cup is rotated. The discharge will be uniform and at the same rate regardless of the size or arrangement of the holes. However, three factors affect the size and uniformity of the droplets: the rate of supply of liquid to the cup 20; the rate of rotation of the cup 20; and the size of the openings 45 in the cup 20.To obtain a uniform droplet size, therefore, the openings 45 are made of constant size in any given cup 20, the cup 20 is rotated at a constant rate by the battery powdered motor 18, and the rate of flow of liquid into the cup 20 is kept constant, as explained hereinbefore.

In each of the embodiments described, when the knob or ioop 33 is pulled upwardly, the switch 35 is closed by the cam 34 to startthe motor 18, and the valve 26 opens, causing liquid to descend by gravity and drip into the rotating cup 20. The liquid is dispersed outwardly and downwardly from the cup 20 in tiny uniform droplets across a 6 to 7 foot diameter area. The diameter of wheels 48, 49 is preferably about 12 inches.

The number and size of the openings 45 in the cup 20 can be varied to control the type of application desired by utilizing interchanging cups. One example is iliustrated in Figure 5. Preferably the openings 45 are round and 3/32 to 1/8 inch in diameter. The cup 20 is rotated at a rate within a range of 3000-7000 r.p.m. but 3000-4000 r.p.m. is preferred. The pipe 30 and the tube 23 have internal diameters of 1/8 to 1/4 inch and provide flow of up to 15 millilitres per second.

With a preferred embodiment, the droplet size is very uniform and there are no large droplets in the pattern nor fine misty droplets which tend to drift with the wind, the effect of wind being considerably less than with pressure-type sprayers.

The downwardly and outwardly extending projections shown in the cup 20 in Figure 7 merely serve to define the circumferentially spaced discharged openings of the cup 20 in this example.

The handle 10 of the embodiment of Figure 7 is detachably connected to the wheeled frame 12 by a tongue and groove connection 64 and is held in place by a resilient detent 65.

The sprayer of Figure 1 or 7 may be used in any reasonably level or unobstructed area with wheeled frame 12engagedto mountthe handle 10. If desired, the frame 12 can be quickly and easily detached and the sprayer may then be utilized manually to apply liquids such as herbicides on higher growing vegetation, flower beds and other more relatively inaccessible areas.

The invention will now be described in more general terms in the following claims and especially

Claims

in claim 1. CLAIMS

1. A portable liquid sprayer comprising: an elongate handle having a forward portion and a rearward end portion; a powered motor mounted on the said forward end portion and having a depending drive shaft; an upwardly facing cup coaxially mounted upon and supported by the lower end portion of the said drive shaft for rapid rotation therewith about a generally vertical axis; a liquid container mounted on the handle is supported elevated relation with respect to the cup and having a lower portion with a liquid outlet; conduit means connected to the said outlet and extending between the container and the cup to convey liquid from the container and discharge the same within the confines of the cup; and valve means for controlling the flow of liquid to the interior of the cup, the cup having a bottom wall and an upstanding side wall or walls and a plurality of circumferentially spaced discharge openings to cause the liquid received within the cup member to be dispersed widely to all sides thereof in tiny droplets when the cup is rapidly rotated by the motor.

2. A sprayer according to claim 1, wherein a wheeled frame detachably supports the said forward portion of the handle.

3. A sprayer according to claim 1 or 2, wherein pressure-sensitive controlled air inlet means are connected to the container for controllably admitting air into the container as liquid is discharged therefrom to thereby control the flow of liquid from the container to the cup.

4. A sprayer according to claim 3, wherein the controlled air inlet means includes a valve element sensitive to difference between the exterior atmospheric pressure and the interior pressure within the container.

5. A sprayer according to claim 3, wherein the said conduit means is connected to the lower end portion of the container and the air inlet means includes an air passage in the lower end portion of the container, and a normally closed valve element disposed within the air passage and being sensitive to difference between the exterior atmospheric pressure and the interior pressure within the container.

6. A sprayer according to claim 3, wherein the controlled air inlet means includes an air inlet located adjacent the point of connection of the said conduit means with the container, and a valve element controlling the air inlet and sensitive to difference between the exterior atmospheric press ure and the interior pressure within the container.

7. A sprayer according to claim 1 or 2, wherein the said side wall or walls have inner surfaces which extend upwardly and inwardly from the outer periphery of the said bottom wall, and the discharge openings of the cup are arranged annularly around the periphery of the bottom wall and extending outwardly and downwardly therefrom to the exterior at the lower edge portions of the outer surface of the said side wall or walls.

8. A sprayer according to claim 7, wherein the said conduit means terminate directly above the bottom wall of the cup and discharge liquid from the container directly upon the upper surface of the bottom wall as it is rotated by the motor.

9. A sprayer according to claim 2, wherein the said frame is supported by a single pair of transversely spaced wheels mounted on a common axis.

10. A sprayer according to claim 2 or 9, wherein readily disconnectable attachment means extending between and connect the handle and the frame whereby the frame may be quickly and easily detached from the handle for manual transport and use of the sprayer absent the frame.

11. A sprayer according to claim 1,2 or 3, wherein the said discharge openings are spaced circumferentially and regularly along the periphery of the bottom wall, and are substantially circular in cross-section and substantially 3/32 to 1/8inch in diameter.

12. A sprayer according to claim 1,2 or 3, wherein the container is generally U-shaped in cross-sectional configuration by virtue of a radially extending slot formed by the periphery thereof and formed of a resilient material; the width of the slot is slightly less than the corresponding dimension of the handle; medial portions of the handle are received within the slot in tight-fitting frictional engagement and support the container thereon; and support means are provided connected to the handle for supporting the container thereon in fixed supported relation.

13. A sprayer according to claim 1,2 or 3, wherein the motor is an electric motor, and battery means are carried by the handle and detachable therewith from the frame; electrical connecting means connect the battery means to the motor in electrical power-transmitting relation; control means mounted on the handle are connected to the valve means in opening and closing relation; switch means are interposed within the said electrical connecting means for opening and closing an electrical circuit between the motor and the battery means, the control means being constructed and arranged to engage and close the switch means when in opening relation with the said valve means, and to open the switch means when in closing relation to the said valve means.

14. Asprayeraccording to claim 10, wherein the said attachment means comprises readily connectable and disconnectable tongue and groove attachment means between the handle and the frame.

15. A sprayer according to claim 1, wherein the said valve means are interposed within the conduit means and control the flow of liquid from said container therethrough to the interior of the cup; and control means are mounted on the handle and connected to the said valve means in opening and closing controlling relation.

16. A portable liquid sprayer substantially as described hereinbefore with reference to Figures 1 to 6 or Figures 7 and 8 of the accompanying drawings.