FR2470367A1 - - Google Patents

Abstract

at. Capacitive filling level measurement probe, comprising an electrode surrounded by an insulating sheath. b. Characterized in that the insulating sheath 5 has an open end extending in the axial direction beyond the electrode 2 and in which is inserted a closure plug 7 which tapers over at least part of its length, with, on the outside , on the end of the sheath, a clamping ring 12 having an inner contour 13 which fits over at least part of its length in a complementary manner to the narrowing 8 of the plug, the insulating sheath 5 being clamped between the surfaces of narrowing 8, 13 of the plug 7 and the clamping ring 12. c. Probe applicable to container fill level monitoring.

Description

1.- 247036;

  The invention relates to a probe for measuring

  capacitive calf, having an electrode wrapped in a gai-

not insulating.

  the insulating sheaths provided for the electrodes are preferably made of material customary on the market, in the form of a tube or flexible hose. The pipe section or flexible pipe used must be sealed in a pressure-tight manner

  at the free end of the electrode. This is usually done-

  by welding a bottom or sticking internally a plug. However, the welding of insulating material requires special machines and special procedures that often

  are lacking, and the collage is too limited as far as

  do the temperatures and pressures of use.

  The aim of the invention is to produce a probe

  measuring the filling level of the type mentioned in

  bule, whose closure is intended for the free end of the galley.

  insulating material is suitable even for use in

  implementation conditions at temperatures and pressures

  latively high, and which can be achieved without difficulty

nor special machines.

  To this end, the invention relates to a filling level measuring probe characterized in that the

  insulating sheath has an open end extending

  axial rection beyond the electrode and in which is inserted a closure plug narrowing on at least ube part of its length, with, externally, on the end of the sheath, a clamping ring having an inner contour which adapts on at least a part of its length in a manner complementary to the narrowing of the plug, the insulating sheath being clamped between the narrowing surfaces of the plug

and the clamping ring.

  Thus, for the free end of the insulating sheath, closure can be achieved with the usual manufacturing facilities (for example towers). The closure

  can be applied very simply on the insulating sheath.

  Moreover, we are not bothered by limitations concerning the

  resistance to pressure and temperature.

  According to one arrangement of the closure, the stopper and the clamping ring are provided with abutments located opposite each other, and between which is mounted a 2.-

compression spring.

  This arrangement always ensures a serviceable force.

  sufficiently high rage on the closure without having to take into account any temperature variations and thermal expansions that result for the insulating sheath. According to one embodiment, an abutment provided

  on the plug is axially adjustable

  the and a spacer is disposed between this stop and

  the plug, or the clamping ring, bearing the other stop.

  These features make it easier

  ge, the adaptation of the end of the sheath to the shape of the

  chon and clamping ring; indeed, it is possible

  to apply a high initial pressure force that exceeds

  the force of the pressure spring. This is particularly advantageous when it is a relatively rigid material of the insulating sheath, for example polytetrafluoroethylene

(PTFE).

  According to one mode of arrangement, the cap comprises

  a central passage bore and an obturating closure element

this piercing.

  This creates the possibility, after the assembly com-

  of the level measuring probe, to fill, if necessary, the support agent the free interior space that presents

possibly the insulating sheath.

  The invention will be better understood using the

  description below and the attached drawing showing an example

embodiment of the invention.

  The single figure of this drawing is a longitudinal sectional view of the capacitive level measuring probe

according to the invention.

  The filling level measuring probe com-

  carries a casing 1 provided for connecting it to a pressure tank, not shown, into which an electrode 2 penetrates

  the measuring probe to monitor the fluid level.

  The electrode 2 consists of a tuft element

  bulaire which is fixed by electrically conductive connection on a contact pin 4 provided in the connection head 3

  1. An insulating sheath 5, electrically non-conductive

  preferably a polytetrafluoroethylene hose,

  surrounds electrode 2. This insulating sheath 5 extends in direction

3.-

  axial downwards beyond the electrode 2.

  - A plug 7 is inserted into the open end of the sheath 5; This plug 7 first has a thickening of conical shape, starting from its end facing the electrode 2, and subsequently has a narrowing of shape.

  8. Outside the end of sheath 5, the

  chon 7 is provided with an axially adjustable stop 9,

  and on which rests, by one of its extremities, a res-

  compression fate 10. By its other end, this spring acts on a stop 11 which has a clamping ring 12, placed

  on the outer sheath 5. This clamping ring 12 presents

  part of its length, an inner contour 13 formed to fit complementary to the narrowing 8 of the

cap 7.

  When placed on the insulating sheath 5,

  lindrique since its connection, the clamping ring 12 is

  first pressed with force against this sheath 5 through

  of the nut 14, the stop 9 and a spacer of tubular shape 15, so that the sheath 5 fits

  exactly to the narrowing 8, 13 of the plug 7 and the

  12. As soon as the sheath 5 is placed approximately in the gripping zone, it is further wedged in a pressure-tight manner between the plug 7

  and the ring 12 under the action of the pressure spring 10.

  the stopper 7 comprises at its center a passage bore 17 to be closed by a closure member 16. By this piercing it is possible, if necessary, to completely fill a

  supporting liquid the interior space 18, 19 of the insulating sheath

lante 5.

4.-

Claims (4)

CLAIMS V E N D I C A T I 0 N S   1.- Capacitive capacitive level measuring probe   pleating, comprising an electrode wrapped in an insulating sheath   characterized in that the insulating sheath (5) has an open end extending axially beyond the electrode (2) and in which is inserted a plug of   closing (7) narrowing on at least a portion of its length   with, externally, on the end of the sheath, a   clamping jig (12) having an inner contour (13) which   fits over at least part of its length in a complementary manner   to the narrowing (8) of the plug, the insulating sheath (5) being clamped between the narrowing surfaces 48, 13)   plug (7) and clamping ring (12).   2. Probe according to claim 1, characterized   in that the plug (7) and the clamping ring (12) are   seen from stops (9, 11) facing one another, and   which is mounted a compression spring (10).   3. Probe according to claim 2, characterized   in that a stop (9) is adjustably arranged in   axial section and a spacer (15) is arranged between   this stop (9) and the stopper, or the clamping ring (12), the other stop (11).   4. Probe according to any one of the claims   1 to 3, characterized in that the plug (7) has a central passage bore (17) and a closure element (16). closing this piercing.