Many designs have been proposed for such dual puipose appliances, but the concept of intercllangeability between wet and dry modes of operation has successfully been applied only in the context of vacuum cleaners of the so-called "canister"type in wluch a cleaning implement to which suction is applied is connected to a source of suction within a body of the appliance by means of a flexible hose. In general, the body of appliances of the canister type can be made relatively large and, indeed, heavy because, whilst it is mobile (on castors or the like) it is not required to be moved constantly back and forts by the user.

However, an alternative form of vacuum cleaner which is in common use is the so-called"upright"type in which a main cleaning implement is cas-sied by a body of the appliance together with a source of suction so that the appliance as a whole is normally required to be moved back and forth by the user. Thus, different constraints on size and weight apply in the case of vacuum cleaners of the upright type, and for this reason it has not previously been possible to provide a commercially successful cleaner of the upright type which is capable of operating in both wet and dry modes.

In our British Patent specifications 1601456 and 9038168 thele are disclosed two vacuum cleaners of the canister type in which a reservoir assembly for a cleaning liquid and a filter assembly for the separation of dry dust are interchangeably assembled between a source of suction and a collection container which is thereby adapted for either wet or dry operation. Thus the main body of the appliance in either mode of operation comprises three sections which are releasably clipped together, the central section comprising either of the two interchangeable sections. Such an arrangement is generally satisfactory for vacuum cleaners of the canister type because they stand stably on the floor and the user can use two hands to manipulate the varions components as necessary without undue difficulty.

Whilst, theoretically, such a tlwee-section construction could be adopted for a vacuum cleaner of the upright type, in practice this has a number of disadvantages to the user in paiicular.

Even where the upright cleaner is of the kind which includes a base member, in which the main cleaning implement and motor/impeller unit are located, with a swivellably connected handle portion carrying the collection container, so that the appliance as a whole can stand stably on the floor with the handle assembly in an upright position, the appliance is generally less stable than a cleaner of the canister type, partly because of its greater height and partly because of the swivellable connection between the handle assembly and the base member, so that manipulation of interchangeable sections to convert from wet to diy mode may be difficult. The difficulties would be even greater with a vacuum cleaner of the so-called"stick"type in which the cleaning implement is not incorporated in a base member whereby the appliance as a whole can stand in a stable manner on the floor.

Our International Patent specifications W094/17722 and W094/17723 disclose an appliance of the stick type in which the collection container is removably housed within a recess formed in a body of the appliance, but without any provision for conversion between wet and dry modes of operation, the collection container being removably coupled at its upper end to an air/liquid separator disposed non-removably within the body of the appliance.

Accordingly, it is an object of the present invention to provide a vacuum cleaning appliance generally of the upright type (which term includes the stick type) which is adapted for operation selectively in wet and dry modes.

According to the present invention we provide a vacuum cleaning appliance of me kind comprising a cleaning implement carried by a body of the appliance which has a source of suction therein and a suction duct connected with said cleaning implement, the body having an opening formed therein at one side to communicate with an internal recess, wherein (a) said recess is adapted to receive selectively and releasably one of two interchangeable first and second collection containers through said opening (b) one of said collection containers is adapted to collect liquid and includes a suction passage which extends upwardly from the base of the container and terminates at an upper end in an outlet at a position within the container and at a lower end in a releasable connection at the base of the container whereby it is connectable to said suction duct, a second releasable connection at the upper end of the collection container whereby it is connectable to said source of suction to establish suction at said cleaning implement and air flow fi-om said implement through said duct and said suction passage to said source of suction, and a wet- mode separator unit connected at the outlet of said suction passage within the collection container and which operates to separate entrained liquid droplets from the air-flow thereby enabling said first collection container when located within the recess to be used for the collection of liquid, and (c) the other of said collection containers is adapted to collect dry matter and includes a suction passage which extends upwardly from the base of the container and terminates at an upper end in an outlet at a position within the container and at a lower end in a releasable connection at the base of the container whereby it is connectable to said suction duct, a second releasable connection at the upper end of the collection container whereby it is connectable to said source of suction to establish suction at said cleaning implement and ail flow fiom said implement through said duct and said suction passage to said source of suction, and a dry-mode separator unit within the collection container at a position spaced from the outlet of said suction passage and which operates to separate dry material entrained in the air-flow thereby enabling said second collection container when located within the recess to be used for the collection of diy matter.

The wet mode separator unit of said first collection chamber may comprise a tube, forcing in use an extension of said suction passage in the collection container, and having an outlet opening in register with a transversely disposed baffle which serves to reverse the direction of air flow and function as an air/liquid separator within said first collection container. Preferably the suction passage is disposed centrally within said first collection container, the tube also being disposed centrally of the collection container.

The baffle is preferably formed with a generally cylindrical skint which extends over, and in spaced relation to, an end portion of said tube, said skirt being spaced inwardly from the side wall of said first collection container.

Desirably, said first collection container also includes an obliquely inclined annular baffle plate which is arranged to extend across the collection container. The annular baffle plate may be carried by an oblique end face at the lower end of a tubular wall which is removably located within said first collection container.

The dry mode separator unit of said second collection container may comprise a filter element disposed within the collection container between the outlet of said suction passage and said connection means at the upper end of the second collection chamber.

The filter element may be cas-sied by a mounting ring which is removably mounted within, and seahngly engages against, the side wall of said collection container, and may be of tubular form and at the end thereof remote from said mounting ring is closed by a baffle plate which, in use, is in register with and spaced from the outlet of said suction passage in said second collection container.

The invention further resides in a collection container for use with a vacuum cleaner of the kind comprising a clearing implement which is car-sied by a body of the appliance together with a source of suction, the body haviez a recess adapted to receive the collection container releasably through an opening formed at one side of the body, wherein the collection container comprises a suction passage which extends upwardly from the base of the container and terninates in an outlet at a position within the container and is releasably connectable at the base of the container to a suction duct in the cleaner, said suction duct being collected with said cleaning implement, connection means at the upper end of me collection container for releasable connection to said source of suction within the body of the cleaner to establish suction at said cleaning implement and airflow from said implement through said suction duct and said suction passage to said source of suction, and a separator unit connected at the outlet of said suction passage and adapted to function as an air/liquid separator operating to separate entrained liquid droplets fi-om the air flow to enable the cleaner to be operated in a wet mode in which said collection container serves to collect liquid picked up by said cleaning implement.

The invention also resides in a vacuum cleaner having such a collection container releasably assembled therewith.

The invention fulther resides in a collection container for use with a vacuum cleaner of the kind comprising a cleaning implement which is carried by a body of the appliance together with a source of suction, the body having a recess adapted to receive the collection container releasably through an opening formed at one side of the body, wherein the collection container comprises a suction passage which extends upwardly fi-om the base of the container and terminates in an outlet at a position within the container and is releasably connectable at the base of the container to a suction duct in the cleaner, said suction duct being connected with said cleaning implement, connection means at the upper end of the collection container for releasable connection to said source of suction within the body of the cleaner to establish suction at said cleaning implement and airflow from said implement through said suction duct and said suction passage to said source of suction, and a separator unit mounted within the collection container at a position spaced from the outlet of said suction passage and adapted to function as a solid matter separator to enable the cleaner to be used in a dry mode, operating to separate solid material entrained in the aiuflow so that said collection container serves to collect dry matter picked up by said cleaning implement.

The invention further resides in a vacuum cleaner having such a collection container assembled therewith.

These and other features of me invention will now be described by way of example with reference to the accompanying drawings wherein :- FIGURE 1 shows one embodiment of vacuum cleaner in accordance with the invention set up in a wet mode with a first collection container in place ; and FIGURE 2 shows such cleaner set up in a dry mode with a second collection container in place.

A suction cleaner embodying the present invention. as illustrated in Figures 1 and 2 by way of example, includes a body 10 which defines a housing for various operative components, including a motor/impeller unit 20 which provides a source of suction to draw air through a suction duct 30 and into one of two removable collection containers 40 and 60 which is for the time-being housed within the body 10.

The body 10 is formed to afford a handle assembly 11 at its upper end and has in its mid region an opening 12 at one side to give access to an internal recess 15 in which the selected removable collection container 40 or 60 is housed when in use. At its lower end the body 10 carries a suction head 70 of any convenient form. It will be understood that such head may, as in the illustrated embodiment, have provision for applying a cleaning liquid as hereulafter described, and that the head 70 may be mounted for swivelling movement relative to the suction duct 30 about a generally horizontal axis extending either in the fore-and- aft direction or in a transverse direction.

In the illustrated embodiment, the first collection container 40 comprises an outer body 41 of generally jug-like form having an integral handle 42 on the wall thereof which in use is outside relative to the recess 15 in the body within which the container 40 is received.

As shown in Figure 1, the outer body 41 of the first container 40 serves as a reservoir compartement for clean water (normally containing a detergent or the like) which can be delivered to the suction head 70 by means of a liquid delivery pipe 31 which is releasably connected to the lower end of the outer body 41, desirably with the interposition of valve means (not shown) whereby the flow of liquid to the cleaning head can be regulated.

The first container 40 further comprises an inner compartment 43 which extends upwardly beyond the upper end of the outer body 41 and at its upper end is adapted to provide a connection 25 to engage sealingly with an intake duct 21 of the motor/impeller unit 20, for example by means of an interpose sealing ring 22.

The inner compartment 43 is adapted to collect material picked up by the suction head 70 and conveyed along suction duct 30. For mis purpose, the inner compartment 43 of the first container 40 includes a suction passage comprising a central suction tube 45 which extends upwardly from the base 44 of the outer body 41 where a releasable connection 44a is provided to connect with the suction duct 30. The tube 45 extends through the base of the inner compartment 43 and terminates at its upper end in an outlet 45a at a position approximately one third of the way up the height of the inner compartment 43.

The inner compartment 43 of the first collection container 40 is provided with a wet-mode separator unit 50 of a kind adapted to separate liquid droplets entrained in the air flow from the suction head 70.

The wet-mode separator unit 50 comprises a tube 51 which is releasably connectable to the outlet 45a at the upper end of the suction tube 45 so as to form an extension thereof. At its upper end 52 the tube 51 carries a cap 53 which includes an end wall 54 of greater diameter than the tube 51, in register with, and spaced from, the upper end 52 of the tube 51 and serves as a baffle, and a circumferential skiit 55 which overlaps with an end portion of the tube 51 in spaced relation therefrom, whilst also being spaced from the side wall of the inner compartment 43 as shown in Figure t. Thus. in use, air with liquid droplets entrained is drawn from the suction head 70, through teh suction duct 30, tubes 45 and 51, and undergoes a sharp reversal of flow within the cap 53, in a manner which efficiently separates liquid droplets before the air flow is again reversed and drawn through connection 5 into the intake duct 21 of the motor/impelleu assembly 20. Liquid separated fi-om the air flow can then drain downwardly into the base of the inner compartment 43.

Preferably, the inner compartment 43 also includes an obliquely disposed annular baffle plate 46 which assists in retaining collected liquid in the base of me inner compartment as the apparatus is moved back and foith.

In the illustrated embodiment, the baffle plate 46 is provided at an oblique end face of an upwardly extending tubular wall 47 which terminates at its upper end in an outwardly directed flange 48 which engages the inner faces of the side walls of the inner compartment, an outlet aperture 49 being formed at the lowest point of the baffle plate 46 at its junction with the wall 47 to allow liquid to be discharged into the base portion of the inner compartment. The baffle plate is arranged so that the aperture 49 is positioned against the side of the inner compartment which is uppermost when the appliance is in use. The baffle 46 prevents spillage of collected liquid into the part of the compartment above the baffle plate if the appliance is laid down and minimises sloshing of the collected liquid due to back and forts movement of the appliance in use. The assembly of baffle plates 46, tubular wall 47 and flange 48 may be removably located within the inner compartment 43 so as to facilitate emptying and cleaning of the latter after use. However, an upwardly extending outlet tube (not shown) may be provided at the uppermost point of the baffle plate 46, diametrally opposed to the aperture 49, to enable the contents of the inner compartment 43 to be emptied without removing the baffle plate assembly, such outlet tube normally being closed at the upper end by means of a suitable removable stopper.

The baffle plate 46 may be secured to. and canied by, the tube 51 of the separator unit 50 so as to form an effectively permanent part thereof, in which case it may be disposed nearer to the cap 53 than illustrated so as to increase the available volume of the inner compartment 43 beneath the baffle plate 46. In other embodiments, the baffle plate 46 may be releasably assembled with the tube 51, or with the suction tube 45 of the collection container 40.

In an alternative arrangement, the tubular wall 47 and flange 48 may be omitted so that the baffle plate 46 then engages around its periphew directly with the internal face of the inner compartment 43, except where the aperture 49 is required.

As described above, the first collection container 40 incorporates a reservoir from which a cleaning liquid may be dispensed as required. However, it would be possible for the inner compartment 43 to be omitted where cleaning by the application of liquid is not required, the outer body 41 then serving directly to collect liquid so that the appliance then serves only to pick up liquid when the first, wet mode, collection container is in use.

For operation of the cleaner in the dry mode, the first, or wet-mode, collection container 40 is removed from the recess 1 5 and the second, or dry-mode, collection container 60 is inselted in its place as shown in Figure 2.

The second collection container 60 comprises a body 61 of generally jug-like folm with an integral handle 62 and a suction passage comprising a central suction tube 63 which extends upwardly from the base 64 of the second collection container 60 where a releasable connection 64a is provided to connect with the suction duct 30. The tube 63 terminates at ite upper end in an outlet 63a. The second collection container 60 is provided with a separator unit 65 wliich may essentially comprise any suitable form of filter element. In the illustrated embodiment a tubular filter element 66 is canied by a mounting ring 67, and the lowermost end of the filter element is closed by a baffle plate 68, on which air emerging from the outlet 63a of the tube 63 impinges so as to cause flow-reversal and to assist the separation of coarser particles before the air stream passes through the filter material which removes finer particles. Separated dust and other matter falls to the bottom of the body 61 of the second collection container 60 as shown, and the container 60 as a whole can be removed laterally from the recess 15 in the housing for emptying as required.

However, it will be appreciated that other forms of filter may be employed if desired. For example, a conventional paper dust-bag with an aperture cardboard mounting may be assembled directly on the tube 63 by inserting the end of the tube through the aperture of the mounting and sliding the mounting over the tube towards the base 64 of the container 60.

When the dry-mode separator unit 60 is in use, the suction head 70 may be exchanged in known manner for a suction head of known type adapted for the pick-up of dry matter. Altematively the suction head 70 may be converted for use as a dry matter pick-up head by means, for example, of an adaptor 75 in the form of a cover plate as described and claimed in our International Patent Application Publication No. W097/29675.