Patent ID: 6064311
Filing Date: 2000-05-16
Classification: F17C,G01M

Abstract:
Process for generating at least one warning signal relating to the level in a tank (3) for storing a product (4) with a view to the restocking of the tank (3), in which at least one measurement sensor (10) associated with the tank (3) is used to determine, at successive instants t.sub.0, t.sub.1 . . . t.sub.i-1, t.sub.i respectively, the values N.sub.0, N.sub.1 . . . N.sub.i-1, N.sub.i of the level of storage of the product in the tank (3), together with the values of the quantity of product .DELTA.N.sub.1, .DELTA.N.sub.2, . . . .DELTA.N.sub.i-1, .DELTA.N.sub.i consumed during the time intervals defined by two successive instants .DELTA.t.sub.1 =t.sub.1 -t.sub.0, .DELTA.t.sub.2 =t.sub.2 -t.sub.1, . . . .DELTA.t.sub.i-1 =t.sub.i-1 -t.sub.i-2, .DELTA.t.sub.i =t.sub.i -t.sub.i-1, comprising the following steps:the measured values N.sub.0, N.sub.1, . . . N.sub.i-1, N.sub.i, together with .DELTA.N.sub.1, .DELTA.N.sub.2, . . . .DELTA.N.sub.i-1, .DELTA.N.sub.i and the associated measurement instants t.sub.0, t.sub.1 . . . t.sub.i-1, t.sub.i are placed in memory,at successive instants .tau..sub.0, .tau..sub.1 . . . .tau..sub.j-1, .tau..sub.j which are spaced apart by time intervals .DELTA..tau..sub.1 =.tau..sub.1 -.tau..sub.0, .DELTA..tau..sub.2 =.tau..sub.2 -.tau..sub.1, . . . .DELTA..tau..sub.j =.tau..sub.j -.tau..sub.j-1 respectively, the time intervals .DELTA..tau. being predefined and their duration being greater than or equal to the time intervals .DELTA.t.sub.n, n being any natural number lying between 0 and i, the values placed in memory of the product quantity consumed .DELTA.N.sub.n during the time intervals .DELTA.t.sub.n are used to calculate a value of the estimated quantity of product C.sub.k which will be consumed between the instant .tau..sub.j and the instant .tau..sub.j+k, .tau..sub.j+k being the k-th instant following .tau..sub.j and spaced apart therefrom by the time interval .delta..tau..sub.k =.DELTA..tau..sub.j+1 +.DELTA..tau..sub.j+2 + . . . +.DELTA..tau..sub.j+k,this value C.sub.k is subtracted from the most recent measured value N.sub.i so as to obtain an estimated value N.sub.i -C.sub.k of the storage level at the instant .tau..sub.j+k,this estimated value N.sub.i -C.sub.k of the storage level is compared with a preset threshold .theta., anda warning signal is generated if the estimated value N.sub.i -C.sub.k is less than the preset threshold .theta..