GB2155241A

GB2155241A - Fluid flow devices

Info

Publication number: GB2155241A
Application number: GB08405477A
Authority: GB
Inventors: Helio Tommasso
Original assignee: Produtos Eletricos Corona Ltda
Current assignee: Produtos Eletricos Corona Ltda
Priority date: 1984-03-02
Filing date: 1984-03-02
Publication date: 1985-09-18
Also published as: GB8405477D0

Abstract

A fluid flow device for use with electric water heaters, comprises a housing (1) defining a receiving chamber (2) connecting with a tubular passage (3), through which fluid can flow to a heating chamber. A movable plate (5) is mounted on a flexible membrane (16) and has a hole (11) which is aligned with a hole (17) in the flexible membrane (16), to thus allow fluid to flow through the chamber (2) and passage (3). Fluid flow moves the movable plate (5) to engage against a countersunk portion (4) of the receiving chamber (2), this movement causing an extension (12) of the plate (5), to move a lever (9) which extends outwardly through a hole (7) in the wall of the tubular passage (3). The lever (9) is sealed in the hole (7) and it outer end (22) supports a head which is connected to movable electric contacts. Fluid flow moves the contacts to engage fixed contacts and make an electrical connection to the heater. <IMAGE>

Description

SPECIFICATION Hydrodynamically controlled driver for electric contacts The present invention relates to hydrodynamically controlled driver for electric contacts.

More particularly, the present invention relates to a device for driving electric contacts by means of an hydraulic flow in order to turn on any type of hydro-thermal electric device, such as electric taps, showers and heaters in general.

According to the present invention there is provided a hydrodynamically controlled driver for electric contacts, for use with electric water heaters, comprising a frame defining a receiving chamber connecting with a tubular passage, through which fluid can flow to a heating chamber, a movable plate having a hole therethrough, being mounted on a flexible diaphragm which also has a hole, said holes being aligned with each other, the periphery of the flexible diaphragm being secured in the frame across the flow path defined by the receiving chamber and the tubular passage, movement of said movable plate being limited in one direction by a countersunk wall portion of the frame, against which the periphery of the plate can engage under the action of fluid pressure, the plate having an extension which can connect with a lever which passes sealingly through the wall of said flow path, the end of said lever outside the flow path supporting a head which holds movable electric contacts.

The present invention uses hydraulic flow to establish a mechanical load on the base of a lever extending outwardly from the device. The transmission power of said load on the lever is multiplied according to the positioning of the lever support point, that is to say, by the ratio of the distance between the support point and the driving end of the lever, to the distance between the support point and contacts on the other end of the lever.

That being so, even having a reduced load inside the device, which load is produced by the flow of running water, a higher load can be obtained at the outer end of the lever for use in the movement of the electric contacts coupled to said lever.

The present invention is advantageous over any other method being presently used for such purpose, due to the fact that it is highly sensitive and can work with any hydraulic flow, either at a high or a low pressure, making the transmission of the hydraulic load very stable for the lever, and consequently the contacts are safe and reliably operated.

The present invention will now be further described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a cross-sectional view of one embodiment of driver constructed according to the present invention and forming part of a heating device.

Figure 2 is a detail of the outer end of the lever of Figure 1, having its own sealing means between the frame and the lever.

Figure 3 is a front view of the movable and fixed contacts and of the respective control head of the embodiment of Figure 1; and Figure 4 is a plan view of the movable lamellar contacts of the embodiment of Figure 1.

The frame or body 1 of the device partially shown in the accompanying drawings, can be either a tap or a shower or any heater. The interior of this body 1 comprises a water receiving chamber 2 which leads to a hollow tubular passage 3 through which water can flow to a constant heating device (not illustrated) and where an electric resistance is located. The receiving chamber 2 is countersunk at 4 to provide a seat and support which limits the stroke of a movable plate 5, the movable plate 5 having a slightly chamfered peripheral edge 6. In the wall of tubular passage 3 there is a hole 7, through which a lever 9 passes, the lever 9 being sealed to the perimeter of the hole 7 by a seal 8. The lever 9 is supported at 10 and extends into the tubular passage 3 and outwardly from its support 10.The movable plate 5 is in the form of a disc which has a hole or an opening 11 which allows water to pass from one side of the disc to the other, the peripheral edge 6 of the plate being complimentory with the countersunk region 4, to thus provide for a perfect fit for plate 5 in the end of passage 3. Said plate 5 has a vertical extension 12 which has a hole in its end region, in which the inner free end 14 of the lever 9 is located. A flexible membrane 16 is fixed on the front face of the movable plate 5 by means of a screw 15.

The flexible membrane 16 is provided with a hole or an opening 17 which coincides with the hole or opening 11 in the plate to thus allow water to pass therethrough. Said membrane 16 has a circular ring-shaped section with a deeply convex profile 18, the periphery 19 of the membrane being secured sealingly between a seat 20 on body 1 and a sieved disc 21 fixed to said body.

The outer end of the lever 9, with respect to tubular passage 3, is indicated by reference numeral 22 and is connected to a head 23 capable of being articulated. The head 23 holds and moves the ends of movable contacts 24, the contacts 24 having a flat semi-circular shape to which respective opposite fixed contacts 25 correspond.

It must be explained that the movable contacts 24 are, in use, connected to the power supply and the contacts or fixed blades 25 are connected to the electric resistance (not illustrated) of the device. The movable contacts 24 have end regions 26 which are fixed to the frame 1 and connected to the power supply; the other end regions 27 being bent and connected to the head 23.

It should be pointed out that the portion of the lever 9 which is located inside the frame in relation to the aperture 7, has a threaded or grooved region 28 onto which a bushing made from elastic material 29 is threaded in a forced way, the bushing extending beyond both ends of said threaded or grooved region 28 and having an elastic membrane 30 constituting an unique body, formed at its outer end.

The membrane 30 is shaped like a disc having a thickened peripheral body portion 31 which is positioned in said hole 7 and sealed by forced fittings 32, said assembly constituting the said seal 8.

Operation: When running water enters the receiv ing chamber 2, the movable plate 5 which restricts waterflowthrough chamber 2 is moved by the water pressure, to engage the countersunk wall portion 4 of chamber 2. Water pressure then holds plate 5 against countersunk wall portion 4, water passing through openings 11 and 17. This movement of plate 5 causes extension 12 to pivot lever 9 about support point 10. The outer end 22 of the lever 9 has a wider movement than the inner end 14, due to the positioning of the support point 10, and this movement of outer end 22 moves head 23 to which the movable contact blades 24 are connected, said movable contact blades 24 then contacting fixed contacts 25 to connect the electric circuit to the electrical resistance (not illustrated) previously mentioned.The water continues flowing, through the openings 11 and 17 in the movable plate 5 and the flexible membrane 16 respectively, and through the duct 3, to the location i.e. heating chamber, where it is heated by the said electric resistance inside the device.

When the flow of water is stopped, a static balance is reached inside the device, and the movable plate 5 is moved away from the countersunk wall portion 4 and returned to its initial position due to the force of the flexible membrane 16 aided by the pressure from the movable contacts 24, which due to their semicircular shape act as springs and displace the head 23. The lever 9 is therefore returned to its initial position and consequently the electric circuit is disconnected.

Considering that device of the present invention operates by the impulse from running water, the flow can be either controlled or interrupted both in the front section of the device or in its rear section, stagnancy of the water causes the moving plate to remain in the movable condition.

Therefore, as above described, one can see that the system when used for contact control is highly efficient, and complete security and reliability of working is obtained, even when the water flow is under a low pressure. Furtherthe above described sealing of the lever in the frame guarantees a perfect and safe sealing.

Claims

1. A hydrodynamically controlled driver for electric contacts, for use with electric water heaters, comprising a frame defining a receiving chamber connecting with a tubular passage, through which fluid can flow to a heating chamber, a movable plate having a hole therethrough, being mounted on a flexible diaphragm which also has a hole, said holes being aligned with each other, the periphery of the flexible diaphragm being secured in the frame across the flow path defined bythe receiving chamber and the tubular passage, movement of said movable plate being limited in one direction by a countersunk wall portion of the frame, against which the periphery of the plate can engage under the action of fluid pressure, the plate having an exten sion which can connect with a lever which passes sealingly through the wall of said flow path, the end of said lever outside the flow path supporting a head which holds movable electric contacts.

2. A hydrodynamically controlled driver as claimed in claim 1, in which the flexible membrane has a deeply convex transverse profile.

3. A hydrodynamically controlled driver as claimed in claim 1 or claim 2, in which the fluid flow path has a sieved disc provided thereacross upstream of said movable plate and said membrane.

4. A hydrodynamically controlled driver as claimed in any one of claims 1 to 3, in which the extension of the movable plate is provided with a hole through which the inner end of said lever extends.

5. A hydrodynamically controlled driver, as claimed in any one of claims 1 to 4, in which the lever is sealed in a hole in the wall of the flow path, by an elastic material bush which is forced onto a threaded region of the lever and extends beyond both ends of the threaded region, a disc-shaped elastic membrane being formed with the bush as a unitory construction, and being secured tightly in the said hole in the wall of the fluid flow path, by means of forced fittings.

6. A hydrodynamically controlled driver as claimed in claim 5, in which the disc-shaped elastic membrane is formed on the end region of the bush nearest to the inner end of the lever, and has a thickened peripheral edge.

7. A hydrodynamically controlled driver as claimed in any one of the preceding claims, in which the movable contacts are flat semi-circular members which are resilient in a spring-like manner, the end regions of said members, remote from said head, being secured to the frame and the other end regions of said members being connected to said head.

8. A hydrodynamically controlled driver for electric contacts, for use with electric water heaters, constructed and arranged substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.