GB2084258A - Improvements in hand operated sprayers - Google Patents

Abstract

A hand-operated sprayer comprises a spray head (1) mounted on a container (2) into which is placed liquid to be sprayed. The spray head incorporates a manual pump (5) in the form of a reciprocating plunger which acts to pressurise the container (2). Liquid leaves the pressurised container (2) upon the opening of the valve (26, 27) by means of a sliding member (35), which can be locked in position to give a continuous spray. Liquid leaves the sprayer through a nozzle (21). <IMAGE>

Description

SPECIFICATION Improvements in hand-operated sprayers This invention relates to hand-operated sprayers of the kind comprising a spray head for mounting on a container for liquid in which the spray head comprises a body provided with an inlet for pressurised liquid, a discharge nozzle, and a manually-operable valve for controlling the discharge through the discharge nozzle of pressurised liquid from the inlet.

In known sprayers of the kind set forth the valve usually comprises a head upon which a spring acts directly to urge it into a closed position in engagement with a seating leading to the nozzle, and a trigger pivotally mounted on the body is angularly movable to urge the head away from the seating to open the valve against the loading of the spring.

In such known constructions the construction and assembly of the manually-operable valve is relatively complicated and utilises a considerable number of components. In addition any pressure in the container acts in the same direction as the spring to augment the force with which the head is urged into engagement with the seating in the closed position of the valve.

According to our invention in a hand-operated sprayer of the kind set forth the nozzle is incorporated in a valve member which is mounted in a bore in the body and is provided at its inner end with a head for engagement with a seating surrounding the inlet, and the valve member is movable through a limited distance with respect to the seating by means of a manually-operable member which is coupled to the valve member and upon which acts a spring for urging the head towards the seating.

Thus the head is urged into engagement with the seating only by the force in the spring, and the pressure acts on the head at all times, thereby assisting any manual force applied to the manually-operable member in direction to open the valve, This has the advantage that by selecting a spring of a suitable strength the valve can open automatically when the container is pressurised to a value slightly below that at which the container can fail. The valve therefore can act also as a pressure-relief or pressure-limiting valve.

In addition to the body our valve only comprises three basic components, namely the valve member, the manually-operable member, and the spring. This provides a simple construction which is relatively simple to produce and in respect of which assembly is simplified.

Conveniently the manually-operable member comprises a push-slide which is detachably assembled by releasable engagements between its opposite ends and the valve member and the body respectively, and the spring comprises a compression spring which acts between the body and the end of the slide which is remote from the valve member.

The slide is conveniently provided at its outer end with spaced lugs which resiliently embrace the valve member and are received in slots in external radial projections on the valve member to define a coupling, and the opposite end of the slide is provided with a thumb piece by means of which the slide can be moved in an axial direction with respect to the bore to open the valve against the loading of the spring.

A sprayer in accordance with our invention is illustrated in the accompanying drawings in which: Figure 1 is a perspective view of the sprayer; Figure 2 is a longitudinal section through the spray head; and Figure 3 is a side view of the spray head.

The sprayer comprises a spray head 1 having a detachable screw-threaded engagement with a container 2 for liquid.

The spray head 1 comprises a body 3 formed with a downwardly depending internally screwthreaded annular skirt 4 which is screwed onto a threaded neck at the upper end of the container 2.

The spray head 1 incorporates a pump 5 for pressurising the container, and the body 3 is provided with a manually-operable valve 6 for controlling the discharge of pressurised liquid from the container.

The pump 5 comprises a hollow tube 7 depending downwardly from the body 3. The tube 7 is provided at its upper end with a radial flange 8 which is sealed in a counterbore 9 by means of a sealing ring 10. The lower end of the tube 7 is provided with a one-way valve (not shown), and the upper end receives a plunger which works in the bore of the tube 7 to force air into the container 2 through the one-way valve by reciprocation of a knob 11 at the free end of a rod 12 which carries the plunger. The flange 8 is held against a shoulder 1 3 in the counterbore by means of a retaining member 14 through which the rod 12 works and which is provided with diametrically spaced lugs 1 5, 16 which are detachably received in complementary notches 1 7 in the body 3.The retaining member 14 is also provided with a pair of lugs 18, 19 which are spaced axially from, and above, the lugs 1 5, 1 6, the purpose of which will be described later.

The valve 6 comprises a valve member 20 comprising a nozzle 21 at the outlet end of cap 22, and a spool 23 onto the outer end of which the cap 22 is screwed and which slides in a bore 24 in the body 3. A seal is provided between the cap 22 and the spool 23. The spool 23 carries an annular seal 25 at intermediate point in its length, and the seal 25 seals against the wall of the bore 24. At its inner end the spool 23 carries a head 26 for engagement with a seating 27 surrounding the inner end of an inlet passage 28 which is connected to the upper end of a dip-tube 29 which extends downwardly towards the base of the container 2. The spool 23 is provided with longitudinally extending passage 30 of which opposite ends terminate in radial passages 31 and 32 of which the passage 32 is disposed between the seal 25 and the head 26.The spool 23 projects from the bore 24 by a substantial distance and at diametrically opposed positions the projecting portion of the spool 23 is provided with a pair of longitudinally extending ribs 33 which are each provided at an intermediate point in its length with a notch 34.

A manually-operable valve-operating member 35 comprises a push-slide which fits on top of the body 3. The slide 35 is of generally inverted U or channel in section and is provided in its top with an elongate slot 36 through which the rod 12 and a portion of the retaining member 14 project. At its forward end the slide 35 is provided with a pair of resiliently deformable lugs 37 which embrace the spool 23 and are releasably received in the notches 34, and at its rear end projections on the sides of the slide 35 are detachably received in elongate notches in the body 3. The engagements of the lugs 37 in the notches 34 and the projections in notches in the body 3 couple the slide 35 to the spool 23 against relative axial movement, and provide a releasable mounting for the slide 35 on the body 3.The rear end of the slide 35 is closed by an inclined wall 38 which is received between spaced flanges 39 of an inclined downwardly depending handle 45 which is integral with the body 3 and by which the sprayer can be held. The inner face of the wall 38 forms an abutment for one end of a compression spring 40 of which the inner end abuts against a shoulder 41 on the body 3, and the outer face of the wall 38 is formed with a series of ribs 42 for engagement by the thumb of the user.

The spring 40 acts through the slide 35 to hold the valve 6 in a closed position with the head 26 in engagement with the seating.

In operation by removing and replacing the spray head 1, the container 2 can be filled to a predetermined level with a liquid to be dispensed.

The container 2 is then pressurised by the pump 5 with reciprocation of the plunger pumping air into the container through the one-way valve at the base of the tube 7. Liquid can then be dispensed from the nozzle 21 in a fine spray by operation of the valve 6 by the slide 35. Movement of the slide 35 by the thumb against the loading in the spring 40 moves the head 26 away from the seating 27 so that pressurised fluid in the container 2 passes to the nozzle 21 through the dip tube 29, the inlet passage 28 and the passages 30,31 and 32.

Normally an intermittent spray under the control of the slide 35 will be required. However, if a continuous spray is required, the slide 35 can be locked in an advanced position in which the valve 6 is open. This is achieved by first detaching the slide 35 from the body 3, and then manipulating the retainer 14 into the position shown in Figure 1 so that a projection 44 extending downwardly from the free end of the body 18 can be detachably engaged with a projection 43 at the rear end of the slot 36 when the slide 35 has been replaced on the body 3 as shown in Figure 3.

Normally, for intermittent operation, the other lug 19, which is piane, is disposed at the rear end of the slot 36 as shown in Figure 2 so that no engagement with the projection 43 can take place.

Since the pressurised contents of the container 2 always act on the head 26 over the area of the seating 27 in a direction to open the valve against the loading of the spring 40, careful selection of the strength of the spring 40 enables the valve 6 to act as a pressure-relief valve and prevent the container from being over pressurised. Normally, therefore, the spring 40 will be at a strength which is substantially less than an equivalent pressure sufficient to cause the container 2 to fail.

In the construction described above only the rod 12 and the spring 40 are of metal and, with the exception of the seals and parts of the valve, the remaining components comprise mouldings of synthetic plastics materials.

Claims (15)

1. A hand operated sprayer of the kind set forth wherein the nozzle is incorporated in a valve member which is mounted in a bore in the body and is provided at its inner end with a head for engagement with a seating surrounding the inlet, and the valve member is movable through a limited distance with respect to the seating by means of a manually-operable member which is coupled to the valve member and upon which acts a spring for urging the head towards the seating.

2. A sprayer according to Claim 1 wherein the spray head incorporates a pump for pressurising the container.

3. A sprayer according to Claim 2 wherein the pump comprises a hollow tube depending downwardly from the body and provided at its lower end with a one way valve, the upper end receiving a plunger which works in the bore of the tube.

4. A sprayer according to any preceding claim wherein the valve member comprises a nozzle at the outlet end of a cap, and a spool onto the outer end of which the cap is secured and which slides in the bore.

5. A sprayer according to Claim 4 wherein the spool carries the head for engagement with the seating surrounding the inlet.

6. A sprayer according to Claim 4 or Claim 5 wherein the spool projects from the bore by a substantial distance.

7. A sprayer according to any preceding claim wherein the inlet comprises the inner end of an inlet passage which is connected to the upper end of a dip-tube which extends downwardly to the base of the container.

8. A sprayer according to any preceding claim wherein the manually-operable member comprises a push slide.

9. A sprayer according to Claim 8 wherein the push slide is detachably assembled by releasable engagements between its opposite ends and the valve member and the body respectively.

10. A sprayer according to Claim 8 or Claim 9 wherein the spring comprises a compression spring which acts between the body and the end of the slide which is remote from the valve member.

11. A sprayer according to any of Claims 8 to 10 wherein the slide is provided at its outer end with spaced lugs which resiliently embrace the valve member.

12. A sprayer according to any of Claims 8 to 11 wherein the slide is provided with a thumb piece by means of which the slide can be moved in an axial direction with respect to the bore.

13. A sprayer according to Claim 11 wherein the spaced lugs are received in notches disposed at intermediate points in the lengths of a pair of diametrically opposed longitudinally extending ribs on the valve member.

14. A sprayer according to any of Claims 8 to 13 wherein the rear end of the slide is closed by an inclined wall.

15. A sprayer according to Claim 14 wherein the inner face of the inclined wall forms an abutment for one end of the compression spring.

1 6. A sprayer according to Claim 14 or Claim 1 5 as dependent from Claim 12 wherein the outer face of the inclined wall is formed with a series of ribs to form the thumb piece.

1 7. A sprayer according to any preceding claim wherein there is provided a handle integral with the body.

1 8. A hand operated sprayer substantially as described with reference to the accompanying drawings.