Solenoid unit and method for producing said solenoid unit and a magnet housing for such a solenoid unit
A solenoid unit for a solenoid valve, including a magnet coil and a ferromagnetic circuit which surrounds the magnet coil and comprises a stationary magnet housing, a movable magnet armature and, if required, an armature antipole, the magnet housing being assembled of a cover, a shell and a bottom in the form of multiplayer transformer sheet metal parts.
1. A solenoid unit for a solenoid valve, comprising a magnet coil and a ferromagnetic circuit which surrounds the magnet coil and includes a stationary magnet housing and a movable magnet armature, wherein the magnet housing is assembled of a cover, a shell and a bottom in the form of multilayer transformer sheet metal parts, said cover comprising an inner cover part and an outer cover part, the outer contour of the inner cover part being complementary to the inner contour of the outer cover part, so that the cover parts can be assembled with an interlocking fit.
2. The solenoid unit according to claim 1 , wherein the transformer sheet metal parts are punched and, if required, bent.
3. The solenoid unit according to claim 1 , wherein the transformer sheet metal parts have a plurality of layers, these layers being connected to each other.
4. The solenoid unit according to claim 1 , wherein at least one of the cover and the bottom has a central opening.
5. The solenoid unit according to claim 4 , wherein at least one of the cover and the bottom has a radial slot that is continuous from the central opening up to the outer periphery.
6. The solenoid unit according to claim 1 , wherein, in the assembled condition, at least one of the cover and the bottom is caulked to the shell.
7. The solenoid unit according to claim 1 , wherein the shell has at least one aperture and the magnet coil is potted, coated or encased by injection-molding.
8. The solenoid unit according to claim 1 , wherein the shell has a thickness that is lower than that of the bottom.
9. The solenoid unit according to claim 8 , wherein the bottom has a thickness that is greater than that of the cover.
10. The solenoid unit according to claim 1 , wherein the outer cover part is formed in the shape of a U.
11. The solenoid unit according to claim 1 , wherein the cover has a covering part which covers the cover parts in the assembled condition.
12. A method of manufacturing a magnet housing of a solenoid unit for a solenoid valve, comprising the following steps:
punching metal sheets of a ferromagnetic material;
stacking the metal sheets to form sheet stacks which are used for one of the shell, the bottom, the cover and a cover part of a magnet housing of the solenoid unit;
assembling said cover from an inner cover part and an outer cover part, the outer contour of the inner cover part being complementary to the inner contour of the outer cover part, said cover parts being connected with at least one of an interlocking fit and a frictional fit;
assembling the magnet housing by producing an interlocking connection between the cover and the shell and between the bottom and the shell.
13. The method according to claim 12 , wherein subsequent to assembling the inner and outer cover parts, a covering part is mounted to at least one of the inner and the outer cover part.