FR2662016A1 - FLOW SWITCH, PARTICULARLY FOR GAS HEATED WALL BOILERS. - Google Patents

Abstract

In the flow switch according to the present invention, which is particularly suitable for wall-mounted gas-fired boilers, the electromagnetic switch or relay (7) with flexible contact blades is incorporated in the body (1) of the switch itself. flow and the body of this switch is made in one piece from a plastic material, this arrangement making it possible to obtain greater sensitivity to the magnetic effect of the magnetic float and a lower cost price.

Description

FLOW SWITCH, PARTICULARLY FOR BOILERS

GAS HEATED WALLS

  The present invention relates to a new flow switch which has a high sensitivity and an ability to repeat its flow rate extremely precisely in operation and which has a price of

returns very weak.

  As is well known, a flow switch is a special device which, based on an electromagnetic principle, allows a flow variation exceeding its sensitivity threshold so as to produce an electrical switching action which can be used to effect a appropriate operation For example, in the case of wall-hung gas-fired boilers, a need for water for domestic use exceeding this sensitivity threshold has the effect that said flow switch switches the boiler from a central heating operation to a heater operation

water for household use.

  This flow switch generally consists of a section of tube which is inserted into the flow path and which comprises two internal projections between which an internal float moves if a flow corresponding to its threshold sensitivity is exceeded, the float being provided with a magnet arranged so as to cooperate with an electromagnetic switch or relay with flexible contact blades, suitably mounted on the body of said tube and electrically connected to the desired actuation circuit In this way , each time the fluid flow exceeds this threshold, the float and, consequently, its magnet approaches the flexible blades which, as a result, move

  so as to close the electrical actuation circuit.

  On the other hand, when the flow rate falls below this threshold, the float can no longer be supported by the flow and moves away from the flexible blades which, therefore, move

  so as to open the above circuit.

  To increase the sensitivity of the flow switch according to the present invention, said flexible contact switch is incorporated in the body of the flow switch so as to be even closer to the magnetic float and, therefore, , to be more sensitive to the magnetic effect of this

  last in order to work even if this effect is weak.

  The body of the flow switch is made by molding in one piece from a non-toxic and water-resistant plastic. In this way, in addition to an obvious economic advantage, an exceptional repetition ability is obtained. of the threshold is sensitivity of opening and closing of the flexible contact blades, given that the mutual position of the elements involved in the actuation of the switch, that is to say the position of the float relative to the flexible contact blades, is always the same, cannot be altered and is substantially independent of magnetic intensity

of said magnet.

  The improved flow switch is therefore particularly suitable for gas-fired wall-mounted boilers, comprising a tubular body through which the flowing fluid passes, an internal float provided with a magnet and which can slide inside said tubular body between two internal projections formed on the body, and an electromagnetic switch or relay with flexible contact blades cooperating with the magnet of the float, this flow switch being characterized, according to the present invention, by the fact that the tubular body of this switch d the flow is produced by molding, in one piece, from a plastic material and that the relay with flexible contact blades is incorporated in this body, the relay with flexible contact blades projecting from said body only by its two metal end plates forming a terminal According to a preferred embodiment of the present invention, the tubular body and the float are made of a plastic material which is not toxic and cannot be attacked by water. The invention will appear more fully in

  the description given below of an embodiment

  preferred for which reference will be made to the single figure of the appended drawing which is a perspective view partially in section of a flow switch produced according to the

present invention.

  In the figure, the reference 1 designates the tubular body of the flow switch, this body being made entirely of plastic and forming a single piece with an internal projection 6 and with two end flanges 2 and 3 serving to fix the flow switch in the path of the fluid flowing and passing through it in the direction indicated by the inlet arrow 4 and the outlet arrow 5 An electromagnetic switch or relay 7 with flexible contact blades is incorporated in the body 1 in such a way that only its two metal end plates forming terminal 8 and 9 protrude The reference 10 designates the internal float which is provided with a magnet il and which, pushed by the flowing fluid, can slide between the internal projection 6 and a ring 12 inserted in the tubular body as far as a shoulder allows

  suitable forming stop 13 formed in this body.

Claims (2)

  1 Flow switch, particularly suitable for wall-hung gas-fired boilers, comprising a tubular body (1) through which the flowing fluid passes, an internal float (10) provided with a magnet (11) and capable of sliding at the interior of said tubular body between two internal projections (6, 12) present on said body, and an electromagnetic switch or relay (7) with flexible contact blades, cooperating with said magnet of the float, characterized in that the tubular body ( 1) the flow switch is produced by molding in one piece from a plastic material and that the electromagnetic switch or relay with flexible contact blades is incorporated in this body, said switch or electromagnetic relay with blade soft contact protruding from the body only by   this metal end plate forming a terminal (8, 9).   2 flow switch according to claim 1, characterized in that the tubular body (1) and the float (10) are made of a plastic material which is not toxic and which cannot be attacked by water.