IE913135A1

IE913135A1 - Float valve for wet and dry vacuum cleaner

Info

Publication number: IE913135A1
Application number: IE313591A
Authority: IE
Inventors: Manfred Diebel
Original assignee: Rowenta Werke Gmbh
Priority date: 1990-09-07
Filing date: 1991-09-06
Publication date: 1992-03-11
Also published as: GB9118978D0; IE66186B1; FR2666499A3; ITMI910754V0; ITMI910754U1; GB2248101A; DE9012775U1; FR2666499B3; IT222495Z2; GB2248101B

Abstract

A float valve is provided for a wet and dry vacuum cleaner having a drive housing and a collection tank. The float valve comprises a heat-deformable annular valve seat 3 projecting downwardly from a base 1 of the drive housing towards the collection tank, a valve closure member 4 provided on a float 5 below the drive housing, and spacer means 7 provided between the base 1 and the float 5, the spacer means 7 being arranged to permit initial valve closure but to limit movement of the float towards the base, whereby upon heat-deformation of the annular valve seat 3 the valve leaks to allow air flow therethrough. Thus overheating and consequent material damage is prevented even if the power supply to the drive is not cut quickly enough. The spacer means may be provided on the float or on the base of the drive housing.

Description

The invention relates to a float valve for wet and dry vacuum cleaners, comprising a valve seat provided on the underside of the base of the drive housing, directed towards the collection tank, and a valve cone with float which is guided in a cage on the underside of the base of the drive housing.

Wet and dry vacuum cleaners comprise a drive portion, in which the motor and the blower are arranged, and a collecting tank suitable for receiving dirt and liquid. The drive portion and collecting tank are detachably connected to one another via a snap connection. The blower is operatively connected with the collecting tank via a suction stream aperture. In these known appliances, a cut-off member interrupts the stream of suction air as soon as the collecting tank is filled to capacity, more particularly when absorbing liquids. This cut-off member consists of a valve seat provided on the underside of the base of the drive housing and a valve cone associated with a float, said valve cone being guided in a cage associated with the above-mentioned underside of the base of the drive housing (DE-OS 28 47 512). These known appliances have the disadvantage that in the event of the collection tank being filled to capacity and the cut-off member being closed, the drive portion is heated to over 100*C within a short time due to the suction stream discharging heat being interrupted, if the vacuum motor - 2 is not switched off when the maximum filling capacity is reached. As a result of overheating, the material of the blower, and the plastics housing is damaged, bringing about the failure of the wet and dry vacuum cleaner.

This invention has the object of providing a protective device for wet and dry vacuum cleaners which prevents the appliance from being damaged when overheated as a result of a closed float valve.

This object is achieved by the characterising features of claim 1.

This invention, prevents any material damages being sustained by the blower, motor and plastics housing due to an overheating of these parts when the tank is filled with liquid and the cut-off element is closed. When the maximum filling capacity of the collecting tank is reached, the cone of the float comes to rest against the valve seat and interrupts the suction air stream. The heat thus developing in the drive portion can no longer be discharged. The temperature of the drive portion quickly increases if the current of the drive motor is not immediately switched off. When a certain internal temperature is exceeded, the valve seat, arranged on the thermoplastic base of the drive housing, becomes deformed. As a result of the vacuum present in the drive housing, the valve seat becomes deformed in the direction of the blower. The float abutting on the valve seat follows this deformation until the spacers are supported on the base of the drive housing. This results in a leakage of the valve as required. The resultant leakage in the valve ends the cessation of the suction air stream. The suction air starts to flow again and the heat accumulation in the drive portion comes to an end and the heat is discharged by the air stream before lasting damages may occur in the drive portion.

Within the scope of the invention the spacers may, - 3 as an equivalent solution, also be connected with the underside of the base of the drive housing outside the valve seat. A known blower gasket which acts as a heat insulation is clamped onto the inside of the base of the drive housing. Advantageously, the width of the circular suction stream aperture of this gasket is larger than the width of the aperture of the valve seat. The region of the housing base outside the valve seat is thus protected against heat by the gasket so that the heating-up of the valve seat is greater than that in the region of the base of the housing protected by the gasket. The vacuum in the drive housing causes a predetermined deforming of the valve seat in the direction of the drive interior until the spacers, supported by the base of the drive housing, abut on the float, thus resulting in the required leakage of the valve.

An embodiment of the invention will now be described in more detail by way of example and with reference to the drawings. Shown are: Figure 1 a partial view of a wet and dry vacuum cleaner having spacers arranged on the float.

Figure 2 a partial view of spacers arranged on the base of the drive housing.

The float valve, shown in Figure 1, consists of an annular valve seat 3 arranged on the underside 2 of the base 1 of the drive housing, and of a valve cone 4 having a float 5. The float 5 is guided in a cage 6 on the underside 2 of the base 1 of the drive housing.

Spacers 7 are formed on the float 5 which project from the valve base 8. If the tank is filled to capacity when absorbing liquids, the float valve interrupts the suction stream and the heat in the drive portion is thus no longer discharged. The base 1 of the drive housing consists of thermoplastic plastics. If a specific temperature is exceeded, the valve seat 3 becomes deformed towards the inside of the drive housing by the vacuum present in the drive portion until the spacers 7 - 4 are supported on the base 1 of the drive housing. This leads to a leakage, as desired, between the valve cone 4 and the valve seat 3. The suction stream starts to flow again and discharges the heat in the driving member 12.

In a further embodiment shown in Figure 2, the spacers 7 are formed on the underside 2 of the drive housing 1, no direct connection existing between the spacers 7 and the annular valve seat 3. A blower gasket 10 is mounted on the inside 9 of the base 1 of the drive housing. The gasket 10 has a circular suction stream aperture 11, the width of which is greater than the aperture width of the valve seat 3. Apart from the valve seat 3, the gasket 10 protects the inside 9 of the base 1 of the drive housing against heat, thus preventing the base 1 of the housing from heating up quicker than the valve seat 3. If the drive portion becomes overheated as a result of a cessation of the suction stream, it is only the valve seat and not the spacers 7 formed onto the base 1 of the drive housing which becomes deformed. In this construction this also results in the desired leakage between valve cone 4 and valve 3 which means that the heat in the drive housing is discharged when the suction stream begins to flow again.

Claims

1. Float valve for wet and dry vacuum cleaner comprising an annular valve seat on the underside of the 5 base of the drive housing, directed towards the collection tank, and a valve cone with a float which is guided in a cage on the underside of the base of the drive housing, characterised in that at least one spacer (7) projecting from the valve base (8) is arranged on 10 the float (5), the height hl of said spacer being equal to or smaller than the height h2 of the valve seat (3).

2. Float valve according to claim 1, characterised in that at least one spacer (7) is connected to the 15 underside (2) of the base (1) of the drive housing outside the valve seat (3) and a gasket (10) known per se having a circular suction stream aperture (11) is clamped onto the inside (9) of the base (1) of the drive housing, the width of said suction stream aperture (11) 20 being greater than the aperture width of the valve seat (3).

3. A float valve for a wet and dry vacuum cleaner, substantially as described herein with reference to and as shown in the accompanying drawings.