AU755406B2

AU755406B2 - A push button bellows arrangement

Info

Publication number: AU755406B2
Application number: AU58360/99A
Authority: AU
Inventors: Colin William Wooldridge
Original assignee: Caroma Industries Ltd
Current assignee: Caroma Industries Ltd
Priority date: 1998-10-26
Filing date: 1999-10-26
Publication date: 2002-12-12
Anticipated expiration: 2019-10-26
Also published as: AU5836099A

Description

S F Ref: 482730

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATBON FOR A STANDARD PATENT

ORIGINAL

Name and Address of Applicant: Actual Inventor(s): Address for Service: Invention Title: Caroma Industries Limited Market Street Brisbane Queensland 4000

AUSTRALIA

Colin William Wooldridge Spruson Ferguson, Patent Attorneys Level 33 St Martins Tower, 31 Market Street Sydney, New South Wales, 2000, Australia A Push Button Bellows Arrangement ASSOCIATED PROVISIONAL APPLICATION DETAILS [31] Application No(s) [33] Country PP6731 Au [32] Application Date 26 October 1998 The following statement is a full description of this invention, including the best method of performing it known to me/us:- 5815 I1- A PUSH BUTTON BELLOWS ARRANGEMENT The present invention relates to a push button bellows arrangement for pneumatically operated cistern mechanisms.

Australian Patent No. 673,959 (previously application no. 77587/94) discloses a cistern arrangement with a push button actuator which is remote from the cistern mechanism and is connected thereto by means of a length of flexible plastics tubing. This has the great advantage that the cistern is able to be mounted in a convenient location and is not obliged to be mounted immediately adjacent to the operating button which is the case if a traditional mechanical linkage between the operating button and the cistern mechanism is provided. In the prior art arrangement the plastics tubing can be up to 4 meters in length and still operate effectively.

The above described arrangement suffered from a number of disadvantages. The first of these is that the push buttons themselves were inserted from the front or face surface of a mounting plate and were therefore liable to be damaged by vandals. The second disadvantage was that the push button was mechanically linked to a bellows arrangement which drew air from behind the mounting plate. Since the mounting plate was secured to the front surface of a wall, this meant that the air being drawn into the bellows arrangement was drawn from behind the wall and normally from within the wall cavity. As a consequence, dust, grit and like abrasive particles were liable to be drawn into the bellows arrangement and disrupt the seal within the bellows. This meant that the effective operating force of the pneumatically powered cistern actuating button could be substantially reduced to the point where the cistern was unable to be operated.

The third problem was the operating efficiency of the bellows arrangement was not as high as was desirable and therefore there was a limit (about 4 metres) to the effective operating length of the tube interconnecting the bellows and the cistern mechanism.

The object of the present invention is to provide a push button bellows arrangement which addresses at least one of the above disadvantages and the preferred embodiment of which addresses all three of the abovementioned disadvantages.

According to a first aspect of the present invention there is disclosed a push button bellows arrangement for pneumatically operated cistern mechanisms, said bellows arrangement comprising a plenum chamber having a compressed air exit leading therefrom, a push button slidably mounted in said plenum chamber for reciprocal movement therein, a spring means associated with said button and plenum chamber to -2urge said button into a rest position and against which work is done in pushing said button out of its rest position, a substantially air-tight sealing means interposed between said button and plenum chamber, and a one way valve means associated with an air inlet to said plenum chamber and arranged to sealingly close said inlet during pushing of said button, wherein said air inlet is arranged to draw air past said button into said plenum via said inlet during return of said button to said rest position.

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According to a second aspect of the present invention there is disclosed a push button bellows arrangement for pneumatically operated cistern mechanisms, said bellows arrangement comprising a plenum chamber having a compressed air exit leading therefrom, a push button slidably mounted in said plenum chamber for reciprocal movement therein, a spring means associated with said button and plenum chamber to urge said button into a rest position and against which work is done in pushing said button out of its rest position, a substantially air-tight sealing means interposed between said button and plenum chamber, and a one way valve means associated with an air inlet to said plenum chamber and arranged to sealingly close said inlet during pushing of said button, wherein said button protrudes beyond the face of a mounting plate and said button and plenum chamber are insertable into said mounting plate from the rear thereof to thereby render said push button bellows arrangement substantially tamper proof when said mounting plate is mounted onto a wall surface.

According to a third aspect of the present invention there is disclosed a push button bellows arrangement for pneumatically operated cistern mechanisms, said bellows arrangement comprising a plenum chamber having a compressed air exit leading therefrom, a push button slidably mounted in said plenum chamber for reciprocal movement therein, a spring means associated with said button and plenum chamber to urge said button into a rest position and against which work is done in pushing said button out of its rest position, a substantially air-tight sealing means interposed between said button and plenum chamber, and a one way valve means associated with an air inlet to said plenum chamber and arranged to sealingly close said inlet during pushing of said button, wherein said plenum chamber closely surrounds the volume through which said button travels from its rest position.

A preferred embodiment of the present invention will now be described with reference to the drawings in which: Fig. 1 is a front perspective view of a dual flush push button bellows arrangement, Fig. 2 is a front elevation of the arrangement shown in Fig. 1, -3- Fig 3 is a plan view of the arrangement shown in Fig. 1, Fig. 4 is an inverted plan view of the arrangement shown in Fig. 1, Fig. 5 is a left elevation of the arrangement shown in Fig. 1, Fig. 6 is a right elevation of the arrangement shown in Fig. 1, s Fig. 7 is a rear view of the arrangement shown in Fig. 1, Fig. 8 is a longitudinal cross sectional view through one of the buttons of the arrangement shown in Fig. 1, the plenum chamber and other operating members of the bellows arrangement having been connected with the buttons, and Fig. 9 is a close-up view of the air inlet opening 15 illustrated in Fig. 8.

As seen in the drawings, the push button bellows arrangement of the preferred embodiment takes the form of a mounting plate 1 having two apertures 5 therein through each of which a push button 2, 3 protrudes. The left hand push button 2 is provided with an indicium 4 to indicate that this push button corresponds to a half flush.

The mounting plate 1 is preferably cast from metal and is provided with two cylindrical collars 6 which open to the rear and which receive the operating components of the bellows as illustrated only in Fig. 8.

As seen in Fig. 8, the bellows takes the form of a moulded plastic substantially cylindrical plenum chamber 8 having a pair of exterior lugs 9 which form a friction fit with the interior of the collar 6. The rear surface of the plenum chamber 8 is provided with a spigot 10 which constitutes an air exit to which a plastic tube (not illustrated) is sealingly engaged in order to transmit compressed air from the bellows to the cistern mechanism (also not illustrated) which is preferably located some distance from the bellows arrangement.

Within the plenum chamber 8 is mounted a cup shaped carrier 12 with which the button 2, 3 is releasably snap engaged by means of an annular rim 13 on the button 2, 3 which snap engages with a like shaped recess formed in the carrier. Four grooves 14 (only two of which are illustrated in Fig. 8) both permit the periphery of the cup shaped carrier 12 to resiliently deform to receive the button 2, 3 and also provide an air passage for air leading into the plenum chamber 8 as will be described hereafter. In the base of the carrier 12 is an air inlet opening 15 and a plurality of protrusions 17. An annular rim 18 surrounds the opening 15 and provides a support surface for a flexible diaphragm 19 which has a number of large apertures therein through which the protrusions 17 pass.

The diaphragm 19 is clamped against the cup shaped carrier 12 by means of a ring 21 which provides a seat for a coil spring 22 and an annular rubber sealing skirt 23.

The button 2, 3, carrier 12, diaphragm 19, ring 21 and sealing skirt 23 are all able to be longitudinally reciprocated within the plenum chamber 8. Manually pressing the button 2, 3 moves the entire subassembly to the right as seen in Fig. 8 until the skirt 23 is in the position indicated by dotted lines in Fig. 8. This compresses the spring 22. When the manual force on the button 2, 3 is released the spring 22 urges the button 2, 3 back into S the rest position illustrated in Fig. 8. It will be apparent to those skilled in the art that this reciprocal movement substantially reduces and then restores the interior volume of the

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plenum chamber 8.

When the button 2, 3 is being pushed, the skirt 23 billows outwardly so as to provide an effective seal between the carrier 12 and plenum chamber 8. In addition, as io indicated in Fig. 9, the flexible diaphragm 19 adopts a generally concave configuration so that the diaphragm 19 sealingly occludes the air inlet opening 15. As a consequence, the carrier 12 operates as a piston and compresses the air within the plenum chamber 8. This compressed air escapes via the spigot 10 and is thereby conveyed to the cistern mechanism.

As the button 2, 3 returns to the rest position under the influence of the energy stored within the coiled spring 22, the diaphragm 19 adopts a generally convex configuration as illustrated by dotted lines in Fig. 9. This allows air to pass through the aperture 5 in the mounting plate 1, through the grooves 14, through the air inlet opening and alongside the protrusion 17 past the apertures (not numbered) in the diaphragm 19 and hence into the interior of the plenum chamber 8.

The above described arrangement provides a number of very substantial advantages. Firstly, because the plenum chamber 8 is inserted into the mounting plate 1 from the rear, the push buttons 2, 3 protrude through the aperture 5 and present a substantially vandal proof exterior. The push buttons 2, 3 cannot be pulled into the interior of the room because the periphery of the cup shaped carrier 12 is larger than the size of the aperture 5. Similarly the push buttons 2, 3 cannot be unscrewed or otherwise turned out since the entire assembly of push buttons 2, 3 carrier 12 and skirt 23 is able to freely rotate within the plenum chamber 8.

Secondly, since the air being drawn into the interior of the plenum chamber 8 is being drawn past the push button 2, 3, this air is clean air from the interior of the bathroom, toilet or similar regularly cleaned room interior. As a consequence, the abovementioned problem of brick dust and the like entering into the bellows arrangement is substantially avoided.

Thirdly, the movement of the push button 2, 3 from left to right as seen in Fig. 8 results in the push button 2, 3 and it associated carrier 12 defining a volume through which these items travel from their rest position. Since this volume is closely surrounded by the plenum chamber 8 the ratio of the interior volume of the plenum chamber with the button in the rest position to the interior volume of the plenum chamber with the button in the fully depressed position, is very high. As a consequence, there is a very substantial change in pressure as a result of the operation of Boyle's Law with the result that plastic tubing of up to 17 metres in length can be utilised between the above described bellows arrangement and the cistern mechanism. This provides much greater flexibility between the mounting position of the cistern operating buttons and the toilet or urinal to be flushed by the cistern thereby overcoming a substantial limitation to architectural design.

The forgoing describes only one embodiment 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 other spring arrangements will be apparent to those skilled in the art.

The term "comprising" as used herein has the inclusive sense of "having" or "including" rather than the exclusive sense of "consisting only of'.

Claims

1. A push button bellows arrangement for pneumatically operated cistern mechanisms, said bellows arrangement comprising a plenum chamber having a compressed air exit leading therefrom, a push button slidably mounted in said plenum chamber for reciprocal movement therein, a spring means associated with said button and plenum chamber to urge said button into a rest position and against which work is done in pushing said button out of its rest position, a substantially air-tight sealing means interposed between said button and plenum chamber, and a one way valve means associated with an air inlet to said plenum chamber and arranged to sealingly close said inlet during pushing of said button, wherein said air inlet is arranged to draw air past said button into said plenum via said inlet during return of said button to said rest position.

2. A push button bellows arrangement for pneumatically operated cistern mechanisms, said bellows arrangement comprising a plenum chamber having a is compressed air exit leading therefrom, a push button slidably mounted in said plenum chamber for reciprocal movement therein, a spring means associated with said button and plenum chamber to urge said button into a rest position and against which work is done in pushing said button out of its rest position, a substantially air-tight sealing means interposed between said button and plenum chamber, and a one way valve means associated with an air inlet to said plenum chamber and arranged to sealingly close said inlet during pushing of said button, wherein said button protrudes beyond the face of a mounting plate and said button and plenum chamber are insertable into said mounting plate from the rear thereof to thereby render said push button bellows arrangement substantially tamper proof when said mounting plate is mounted onto a wall surface.

3. A push button bellows arrangement for pneumatically operated cistern mechanisms, said bellows arrangement comprising a plenum chamber having a compressed air exit leading therefrom, a push button slidably mounted in said plenum chamber for reciprocal movement therein, a spring means associated with said button and plenum chamber to urge said button into a rest position and against which work is done in pushing said button out of its rest position, a substantially air-tight sealing means interposed between said button and plenum chamber, and a one way valve means associated with an air inlet to said plenum chamber and arranged to sealingly close said inlet during pushing of said button, wherein said plenum chamber closely surrounds the volume through which said button travels from its rest position.

4. The arrangement as claimed in any one of claims 1-3 wherein said one way valve means comprises a flexible diaphragm mounted over said air inlet.

The arrangement as claimed in any one of claims 1-4 and having a dual bellows arrangement whereby said dual buttons respectively operate a dual flush cistern mechanism.

6. A push button bellows arrangement substantially as described herein with reference to the accompanying drawings. Dated 8 November, 1999 Caroma Industries Limited Patent Attorneys for the Applicant/Nominated Person SPRUSON FERGUSON