Electromagnet and method to produce the electromagnet
An electromagnet and method for producing an electromagnet. The electromagnet includes a sheet metal casing encompassing a magnetic coil at its end face on a magnetic pole side and extends into an interior of the magnetic coil and forms, in this case, a magnetic pole which interacts with a magnet keeper. The electromagnet enables actuation of a valve, a coupling or a reciprocating pump. The structure is achieved with as few cutting processes as possible to be used for generating the individual parts and as small a number as possible of individual parts is to be used per electromagnet.
1. An electromagnet, comprising:
at least one magnetic coil;
a magnet keeper;
a yoke; and
an iron backplate;
wherein the iron backplate includes a sheet metal casing which encompasses the magnetic coil at least at its circumference;
wherein the sheet metal casing encompasses the magnetic coil also at its end face on a magnetic pole side and extends into an interior of the magnetic coil and forms, in this case, a magnetic pole which interacts with the magnet keeper:
wherein the magnetic pole is formed by a plurality of protruding zones and recessed zoned extending beyond an inner circumference of the sheet metal casing.
2. The electromagnet according to claim 1 , wherein the sheet metal casing is produced from a circular blank as a result of a stamping and forming process.
3. The electromagnet according to claim 1 , wherein the sheet metal casing is produced from a circular blank as a result of a stamping and forming process.
4. The electromagnet according to claim 1 , wherein the sheet metal casing is produced from solid material as a result of a machining process.
5. The electromagnet according to claim 1 , wherein the sheet metal casing is produced as a result of a MIM (metal injection moulding) process.
6. The electromagnet according to claim 1 , wherein the sheet metal casing is produced as a result of a combination of at least two processes, selected from the group stamping and forming, sintering, machining and MIM.
7. An electromagnet, comprising:
at least one magnetic coil;
a magnet keeper;
a yoke; and
an iron backplate;
wherein the iron backplate includes a sheet metal casing which encompasses the magnetic coil at least at its circumference;
wherein the sheet metal casing encompasses the magnetic coil also at its end face on a magnetic pole side and extends into an interior of the magnetic coil and forms, in this case, a magnetic pole which interacts with the magnet keeper;
wherein the magnetic pole is formed by a plurality of protruding zones and recessed zoned extending beyond an inner circumference of the sheet metal casing:
wherein the magnetic pole comprises a form which deviates considerably from a cylindrical form by zones which protrude axially beyond the circumference by more than 0.2 mm, preferably by more than 1 mm, further preferably by more than 2 mm, and axially recessed zones alternating.
8. The electromagnet according to claim 7 , wherein the protruding zones are connected to the recessed zones of the magnetic pole by first flanks and by second flanks, wherein the absolute angles of the first flanks to the centre line of the electromagnet differ from the absolute angles of the second flanks to the centre line by at least 3°, preferably by more than 5°, further preferably by more than 10°.
9. A method for producing an electromagnet which includes at least one magnetic coil, a magnet keeper and an iron backplate, wherein the iron backplate includes at least of one yoke and one sheet metal casing which encompasses the magnetic coil at least at its circumference, the method comprising:
the sheet metal casing is produced as a result of forming from a circular blank which is perforated and/or cut in its centre as a result of stamping;
the centre of the circular blank is inverted in such a manner that it extends into an interior of the sheet metal casing; and
the form of the perforation of the centre produces protruding zones and recessed zones of a magnetic pole which is generated by an inverting process;
wherein the magnetic pole comprises a form which deviates considerably from a cylindrical form by zones which protrude axially beyond the circumference by more than 0.2 mm, preferably by more than 1 mm, further preferably by more than 2 mm, and axially recessed zones alternating.
10. An electromagnet, comprising:
at least one magnetic coil;
a magnetic keeper; a yoke; and
a sheet metal casing having an annular end face, an outer upturn wall, and an inner upturned wall;
wherein the sheet metal casing encompasses the magnetic coil at least at a circumference and an end face of the magnetic coil;
wherein the inner upturned wall of the sheet metal casing extends into an interior of the magnetic coil to form a magnetic pole that interacts with the magnetic keeper;
wherein the inner upturned wall includes at least one axially extending protrusion that extends beyond an inner circumference of the inner upturned wall to form the magnetic pole.