Apparatus and method for recirculating machine tool coolant and removing ferrous debris therefrom
View Patent ↗An apparatus and method for recirculating machine tool coolant in which coolant and entrained debris flowing in a shallow stream trough are raised to a higher level by rotation of a bladed wheel in a housing arranged to receive the liquid flow stream. Coolant and debris is then directed down at a magnetized body in a plunging discharge to bring ferrous debris into contact with an upwardly facing surface of the magnetized body. The coolant and nonferrous remaining entrained debris is collected in a tank and pumped back to the filter apparatus by a chopper pump which has a hardened impeller having cutting edges cutting up the remaining debris as it is pumped by the impeller.
1. Apparatus for recirculating machine tool coolant and entrained debris flowing in a shallow depth stream within a flow channel to a filtration apparatus, said apparatus comprising:
a housing having an inlet opening connected to said channel to receive said flowing stream of coolant onto a bottom wall of said housing;
a bladed wheel rotatably mounted within said housing and a drive motor for rotating said bladed wheel therein;
said bladed wheel having a plurality of outwardly extending blades attached to a hub structure, said blades generally conforming to the cross sectional shape of an interior shape in said housing receiving said stream of flowing coolant and rotated in the same direction of said stream flow, said blades each having an outer edge passing over said bottom wall and sweeping said coolant in said stream therealong;
said housing interior space defined by a wall surface curving upwardly along the path which said outer edges of each of said blades move so as to enable said coolant to be swept therealong and upwardly by rotation of said bladed wheel;
said upwardly curving surface extending to a rearwardly and upwardly extending exit wall having a weir edge defined at an upper region thereof, coolant slung over said weir edge entering a discharge chute; said bladed wheel rotated by said drive motor to achieve sufficient blade velocity to sweep coolant upwardly and to sling said coolant up said exit wall, over said weir edge and into said discharge chute;
a magnetized body disposed at a lower level below said discharge chute to receive descending coolant and debris so as to bring ferrous debris into contact therewith to be captured thereon by magnetic attraction;
a collection tank receiving coolant flowing off said magnetized body; and
a pump associated with said collection tank causing coolant and remaining debris collected in said collection tank to be circulated to said filtration apparatus.
2. The apparatus according to claim 1 wherein said pump comprises a chopper pump having an impeller formed with cutting edges cutting up entrained debris drained within a pump casing enclosing said impeller.
3. The apparatus according to claim 2 wherein said pump further includes an agitator tool attached to said impeller to rotate therewith and located to break up debris prior to entering said pump casing.
4. The apparatus according to claim 1 wherein said magnetized body is mounted to present an inclined surface against which said debris and entrained coolant plunges to bring any ferrous debris therein into contact therewith.
5. The apparatus according to claim 1 wherein said magnetized body is a rare earth magnet.
6. The apparatus according to claim 1 , further including a series of shed plates mounted around said magnetized body so as to direct coolant and entrained debris from said discharge chute onto an upper surface of said magnetized body.