Wear particle disintegrator monitor

• US 4,302,754 A
• Filed: 02/12/1979
• Issued: 11/24/1981
• Est. Priority Date: 02/12/1979
• Status: Expired due to Term

• Current Assignee: Vickers Incorporated (Eaton Corporation PLC.)
• Original Assignee: Medical Development Corporation
• Inventors: Tauber, Thomas E., Magee, James H.
• Primary Examiner(s): Caldwell, Sr., John W.
• Assistant Examiner(s): Nowicki, Joseph E.
• Application Number:
  US06/011,553
• Time in Patent Office: 1,016 Days
• Field of Search: 340/526, 340/627, 340/631, 340/682, 324/204, 324/213, 324/235, 200/61.09, 235/92 PC, 210/223
• US Class Current: 340/631
• CPC Class Codes: F01M 2001/1042 comprising magnetic parts
• CPC Class Codes: G01N 15/1031 by measuring electrical or magnetic effects
• CPC Class Codes: G01N 33/2858 Metal particles

Abstract

An electromagnetic system is provided to monitor the activity of a ferrous debris detector of the type which uses electric discharges to automatically disintegrate magnetically concentrated accumulations of micron sized wear particles in hydraulic systems. The data provided are used to detect instances of abnormal wear as shown by either an unusually large number of such discharges or an excessive rate of discharge. Where such abnormality occurs the monitor will provide an audiovisual alarm to warn of the problem in time to prevent catastrophic failure of the system.

Claims

1. An apparatus for the attraction, collection and destruction of wear particles in fluid systems and adapted to provide output information on apparatus performance comprising:

a wear particle detector means for generating wear particle signals representative of critical particle size and non-critical particle size, respectively,

said wear particle detector means including a digital pulse generation means for generating said wear particle signals as digital pulses whenever a wear particle of non-critical size is destroyed; and

a counting means adapted to be connected to said digital pulse generation means to keep a record of the number of said digital pulses.

2. The apparatus as defined in claim 1 wherein said wear particle detector means is adapted to be connected to an electric power source and further comprises:

a pair of electrodes of electrically and magnetically conductive materials spaced apart so as to form an operational gap of predetermined dimensions and thereby constituting a discontinuity of an energized electric indicating circuit adapted to attract and collect wear particles;

a means to provide a magnetic field between said electrodes;

a capacitor connected in parallel with said operational gap so as to cause a release of the charge on said capacitor through a particle or aggregation of particles of such size as to close the electric circuit, said released charge being of sufficient magnitude to disintegrate non-critical size particles, thus causing said circuit to reopen and said capacitor to recharge;

alarm means connected to said capacitor and activated whenever said capacitor discharge fails to destroy a wear particle so that said electric circuit remains closed to generate said wear particle signal representing a critical size particle;

suppression means for preventing transients resulting from said discharge from affecting other parts of the wear detector which includes a power source and means for transmitting said power to the capacitor and said electrodes; and

bleeder means for the gradual discharging of said capacitor whenever said power source is turned off.

3. The invention according to claim 2 wherein said digital pulse generation means comprises:

a circuit parallel to said electric circuit adapted to detect the opening of said electrical circuit, said parallel circuit being adapted to generate said digital pulses in response to said release of the charge on said capacitor and subsequent capacitor recharge for use with said counting means to record the number of wear particle disintegrations.

4. The invention of claim 3 wherein said counting means comprises:

a positive sensing digital meter adapted to sense and count said digital pulse upon recharging of said capacitor after the disintegration of a wear particle; and

time delay means to prevent spurious event counts resulting from pulses generated from the capacitor recharging after being discharged by said bleeder means from reaching said meter.

5. The invention of claim 4 wherein said meter comprises a timing means operably connected thereto adapted to determine the rate of which capacitor discharges and recharges are occurring in a given period of time.

6. The invention of claim 5 wherein said timing means comprises an oscillator adapted to emit timing pulses whenever said capacitor discharges and recharges, said timing pulse being adapted to being counted by an integral timing count register for a preselected period of time, said timing means being further adapted to activate a second alarm means if a second capacitor discharge and recharge occurs while said timing count register is still counting said timing pulses.

7. The invention of claim 5 wherein said timing means comprises:

a plurality of integral timing count registers operably connected to said meter and adapted to allow the delay of alarm activation until a preselected number of capacitor recharges occur within said preselected time whereby a separate counter is used to record the time which elapses from when each capacitor recharge occurs and further including means for operably connecting said registers for receiving a signal indicative of capacitor recharge; and

event counting means adapted to determine at any time how many of said counters are in operation so that if N-1 counters, where N is the preselected number of charges to activate said alarm, are counting when the Nth recharge occurs, said alarm means is activated.