NZ597121A

NZ597121A - Dual flush tipping bucket cistern, controlled by water level sensor with flushing in alternate rotational directions for reduced or full flush volume

Info

Publication number: NZ597121A
Application number: NZ59712107A
Authority: NZ
Inventors: Sam Robertson England
Original assignee: Caroma Ind Ltd
Priority date: 2006-08-11
Filing date: 2007-08-09
Publication date: 2012-03-30
Also published as: AU2007283451B2; AU2007283451A1; NZ573411A; WO2008017114A1

Abstract

The dual flush tipping structure is rotatable in clockwise or counter-clockwise directions to respectively provide reduced volume flush or full flush. This is provided for by the overflow construction of compartments and water level sensor typically float arm 50 acting on inlet valve (not shown).

Description

PATENTS FORM 5 PATENTS ACT 1953 COMPLETE SPECIFICATION Our Ref: 837905NZD1 Dated: 14 December 2011 Tipping bucket cistern, mechanism & method We, Caroma Industries Limited, incorporated in an Australian company, ACN 000 189 499, of 10 Market Street, Brisbane, Queensland, 4000, Australia, hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: 0013E(5835292_1 ):RDC 1 TIPPING BUCKET CISTERN. MECHANISM & METHOD Field of the Invention The present invention relates to cisterns (or flush tanks as the devices are known in the United States of America).

Background Art One category of cisterns are those which incorporate a tipping bucket or buckets. Examples of such cisterns are disclosed in US Patent No. 4,646,369 (NRDC) and US Patents 5,887,293 and 6,611,967 (both to Hennessy).

Such tipping bucket cisterns suffer from a number of disadvantages including that the axis of rotation of the bucket is aligned with the longitudinal axis of the cistern thereby generally resulting in a lever actuator which is used to initiate the tipping action being located to one side of the cistern. Generally this is the right side as viewed by a user about to flush the cistern, however, this disadvantages left handed users. This is to be contrasted with the category of cisterns which utilise an underwater valve and utilise push button operation. Such push buttons are normally centrally located on the top of the cistern and thus the arrangement is equally convenient for both left and right-handed users.

Genesis of the Invention The genesis of the present invention is a desire to improve the operation of tipping bucket cisterns.

AH21(5828195_1):MAH 2 Summary of the Invention In accordance with a first aspect of the present invention there is disclosed a dual flush cistern having a first and a second tipping bucket which are pivotable together, said buckets being tipped in a first direction to provide a low volume flush and being tipped in s a second direction to provide a high volume flush, wherein a water inlet is directed into said first bucket, said second bucket includes a water level detection means operable to open or close said water inlet in accordance with whether said second bucket is at least partially empty or is substantially full respectively, and said first bucket includes an overflow means arranged to direct water from said first bucket when substantially full 10 into said second bucket.

In accordance with a second aspect of the present invention there is disclosed a method of refilling first and second tipping buckets of a dual flush cistern, said tipping buckets being pivotable together, said buckets being tippable in a first direction to AH2l(5828195_l):MAH RECEIVED at IPONZ on 22 February 2012 3 provide a low volume flush and said buckets being tippable in a second direction to provide a high volume flush, said method comprising the steps of: (i) directing a water inlet into said first bucket, (ii) providing said second bucket with a water detection means operable to open or close said water inlet in accordance with whether said second bucket is at least partially empty, or is substantially full respectively, and (iii) providing said first bucket with an overflow means directed into said second bucket.

Brief Description of the Drawings Two preferred embodiments of the present invention will now be described with reference to the drawings in which: Fig. 1 is a perspective view of the cistern of the preferred embodiment; the inlet and control float being omitted so as not to overburden the drawings, Fig. 2 is a vertical cross-sectional view of the cistern of Fig. 1 with the housing being shown in cross-section and the cistern mechanism being illustrated in front elevation, Fig. 3 is a perspective view of the cistern mechanism of Figs. 1 and 2, AH21(5828195_2):MAH Fig. 4 is an exploded perspective view of the cistern mechanism of Fig. 3, Figs. 5-10 are front elevational views of the cistern mechanism illustrating the sequence of events in relation to a reduced flush, Figs. 11-16 are front elevational views of the cistern mechanism illustrating 5 the sequence of events in a full flush, Figs. 17-20 are equivalent to Figs. 1-4 but illustrating one embodiment of the water supply arrangements for an inlet mechanism, Figs. 21-26 are equivalent to Figs. 5-10 but illustrates a float arm positioned within the second bucket, and 10 Figs. 27-32 are equivalent to Figs. 11-16 but again illustrating a float arm positioned in the second bucket.

Detailed Description As seen in Figs. 1-4, the cistern 1 of the first embodiment has a cistern housing 15 2 which takes the form of a body 3 and a top 4. Located within the body 3 is a water director 6 which constitutes a hollow half cylinder and which is directly connected to the flush pipe 7 of the cistern 1.

In addition, as best seen in Fig. 4, the water director 6 includes two U-shaped 20 bearings 8 which support a combination bucket 9 having a pair of stub axles 10 (only one of which is visible in the drawings).

The combination bucket 9 takes the form of a first bucket 11 and a second bucket 12 which have a common axis of rotation 14 defined by the stub axles 10. The 25 first and second buckets 11, 12 are preferably of the same size and have a common wall 16. The first and second buckets are each half cylinders with the axis of the cylinders being the axis of rotation 14. The second bucket 12 has an open top 18 whilst the first bucket has a cover 19 which is also substantially half-cylindrical. As a consequence, the first bucket 11 and its cover 19 together constitute a substantially 30 hollow cylinder.

In the circumferential wall of the cover 19 is located an exit aperture 21 through which water in the first bucket 11 can exit. In addition, in the common wall 16 is a transfer aperture 22 which enables water to transfer between the buckets. As will be explained hereafter, the preferred inlet arrangement is for water to be delivered into the first bucket 11, to transfer via the transfer aperture 22 into the second bucket 12 and for the level of water in both buckets to be controlled by the level of water in the second bucket 12.

Preferably the combination bucket 9 is provided with two lips 24, 25 which extend in opposite directions and over which water pours as will be described in relation to Figs. 5-16. The combination bucket 9 is preferably also weighted by a slight mis-alignment of its centre of gravity and the axis of rotation 14 so that the empty combination bucket 9 returns to the upright position illustrated in Figs. 1-4 under the influence of gravity.

Turning now to Figs. 5-10, the sequence of events in creating a reduced flush (typically three litres) will now be described. Fig. 5 illustrates the rest position of the combination bucket 9 with both buckets full of water. The combination bucket 9 is rotated by any convenient mechanism clockwise as seen in Fig. 6. As a consequence, the water within the second bucket 12 pours over the lip 25 as a result of the open top 18 of the second bucket 12. This pouring action reinforces the initial impetus given to the combination bucket 9 which therefore continues to rotate approximately 90° into the position illustrated in Fig. 7. As a consequence, the second bucket 12 is substantially entirely drained of water which enters the flush pipe 7.

However, only water from the second bucket 12 enters the flush pipe 7 because the water in the first bucket 11 is retained within the first bucket 11 by means of the cover 19. In particular, the exit aperture 21 of the cover 19 is uppermost and therefore no water exits the first bucket 11 via the exit aperture 21. A similar situation applies in relation to the transfer aperture 22.

When the second bucket 12 has drained, the reduced volume flush is completed and the combination bucket rotates in an anti-clockwise direction as seen in Fig. 8 back towards the rest position which is illustrated in Figs. 9 and 10. As the transfer aperture 22 approaches the rest position, so the level of water within the first bucket 11 reaches the lower edge of the transfer aperture 22 thereby resulting in water overflowing from the first bucket 11 to the second bucket 12. In addition, the inlet 6 mechanism (to be described hereafter) being controlled by the level of water in the second bucket 12 turns on thereby delivering water to the first bucket 11. Water is continually transferred from the first bucket 11 to the second bucket 12 until both buckets reach the same level at which the level of the second bucket 12 controls the 5 inlet mechanism and stops the delivery of water to the first bucket 11.

The sequence of events constituting a full flush (typically six litres) is illustrated in Figs. 11-16. From the rest position illustrated in Fig. 11, the combination bucket 9 is rotated in an anti-clockwise direction by any convenient 10 means as illustrated in Fig. 12. As a consequence, water pours over the lip 24 from both the first bucket 11 via the exit aperture 21 and from the second bucket 12 via the open top 18. The water flowing over the lip 24 reinforces the initial rotary impetus and thus the combination bucket 9 continues to rotate through approximately 90° as illustrated in Fig. 13. Both buckets 11,12 drain simultaneously into the flush pipe 7.

When both buckets 11, 12 are empty, the combination bucket 9 returns in a clockwise direction as illustrated in Fig. 14 back towards the rest position illustrated in Figs. 15 and 16. Again the inlet mechanism controlled by the level of water in the second bucket 12 delivers water to the first bucket 11 which as it fills reaches a water 20 level coincident with the lower edge of the transfer aperture 22. This therefore results in water transferring from the first bucket 11 into the second bucket 12. Eventually the position is reached as illustrated in Fig. 16 where both buckets are full and the water level within the second bucket 12 causes water flowing into the first bucket 11 to cease flowing.

Turning now to Figs. 17-20, a second embodiment of the present invention is illustrated in which details of the flush actuator 30 and inlet supply 40 are illustrated. The flush actuator 30 is centrally located on the top 4 and constitutes an inverted Y-shaped body 31 which is pivoted at 32. The circumferential wall of the cover 19 is 30 provided with a lug 33 which, in the rest position of the combination bucket 9, is positioned between the arms of the Y-shaped body 31. As a consequence, movement of the stem of the Y-shaped body 31 to either the right or the left induced by the hand of a user, initiates rotation of the combination bucket 9 in either an anti-clockwise direction or a clockwise direction respectively. 7 As best seen in Fig. 20, the inlet supply 40 includes an elbow 41 having a pair of sealing O-rings 43 positioned on a spout 44 which extends through the stub axle 10 and opens into the first bucket 11. A flexible hose 45 as seen in Figs. 17 and 18 5 interconnects a mains supply 47 with the elbow 41.

As seen in Figs. 21-32, a float arm 50 is provided above the second bucket 22 and senses the level of water within the second bucket. When the water level drops the float arm 50 opens a valve (not illustrated) contained within the spout 44 to 10 thereby permit water to flow from the main supply 47 into the first bucket 11. Conversely, when the water level within the second bucket 12 reaches its maximum desired level, the float arm 50 rotates so as to close the valve within the spout 44 and cease that water delivery.

The foregoing describes only two embodiments of the present invention and modifications, obvious to those skilled in the art, can be made thereto without departing from the scope of the present invention. For example, the buckets 11, 12 need not be cylindrical since a generally rectangular shape will achieve the same ends. However, the cylindrical shape illustrated has the advantage of less turbulent water 20 delivery. In addition, it is similarly not essential for the first and second buckets to have the same axis of rotation, nor is it essential for the first and second buckets to be fabricated in a single piece to form the combination bucket 9. Similarly, clearly a single flush cistern can be created using just a second bucket 12.

The above described arrangements have a number of advantages. Firstly, the flush actuator 30 is able to be positioned centrally on the top 4 in such a way to be entirely neutral as to whether the person operating the cistern is left or right handed. This is to be contrasted with the arrangements illustrated in the abovementioned prior art where a rocker arm is located to one side of the cistern and therefore at least some 30 users will be disadvantaged depending upon whether they are right or left-handed.

Furthermore, the housing 2 is shaped to be wall mounted to the rear of a lavatory pan upon which a user sits. The housing 2 has a front to rear (transverse) axis and a left to right (longitudinal) axis both defined by the intended orientation of 8 the user whilst sitting on the pan. The cistern tipping bucket or buckets is/are pivotally mounted within the housing 2 so that the axis of rotation (eg. 14) of the or each tipping bucket is substantially parallel to the front to rear axis. That is the axis of rotation 14 is transverse to the longitudinal axis of the cistern housing 2. Thus the 5 entire arrangement is able to be fabricated in a much more compact manner than in the abovementioned prior art. This leads to a cistern housing 2 of conventional dimensions which therefore has increased market appeal.

The term "comprising" (and its grammatical variations) as used herein is used 10 in the inclusive sense of "including" or "having" and not in the exclusive sense of "consisting only of'.

RECEIVED at IPONZ on 22 February 2012 9

Claims

Claims:

1. A dual flush cistern having a first and a second tipping bucket which are pivotable together, said buckets being tipped in a first direction to provide a low volume flush and being tipped in a second direction to provide a high volume flush, wherein a water inlet is directed into said first bucket, said second bucket includes a water level detection means operable to open or close said water inlet in accordance with whether said second bucket is at least partially empty or is substantially full respectively, and said first bucket includes an overflow means arranged to direct water from said first bucket when substantially full into said second bucket.

2. The dual flush cistern as claimed in claim 1 wherein said water level detection means comprises a float and float arm extending into an at least partially open top of said second bucket.

3. A method of refilling first and second tipping buckets of a dual flush cistern, said tipping buckets being pivotable together, said buckets being tippable in a first direction to provide a low volume flush and said buckets being tippable in a second direction to provide a high volume flush, said method comprising the steps of: (i) directing a water inlet into said first bucket, (ii) providing said second bucket with a water detection means operable to open or close said water inlet in accordance with whether said second bucket is at partially empty, or is substantially full respectively, and (iii) providing said first bucket with an overflow means directed into said second bucket.

4. The method as claimed in claim 3 including the steps of: (iv) forming s aid water detection means as a float and float arm which extend into an at least partially open top of said second bucket. Caroma Industries Limited By the Attorneys for the Applicant SPRUSON & FERGUSON AH21(5828195_2):MAH