A spool arrangement 1 is described comprising a spool member (47) having a coil embedded in a spool housing (48) made of plastic material and protection means (2, 13, 28) comprising at least two parts together forming a receiving volume (46), said spool member (47) being located in said receiving volume. Such a spool arrangement (1) should be used in an environment in which there is a risk of explosions. To this end said parts form protective walls on all sides of said receiving volume (46).

A solenoid contains a yoke, a bobbin having an electromagnetic coil disposed inside the yoke, and an iron core disposed inside the bobbin. In the solenoid, a connector part incorporating a prescribed number of terminal metal fittings is provided on one end portion of the bobbin.

The actuator (10) comprises a body (12) formed by a single strip of ferromagnetic material, U-shaped and including a first and a second lateral branch (14, 16) facing each other and interconnected by an intermediate branch or portion (8). A first lateral branch (14) of the body (12) has a frustoconical formation (30) which extends in the region outside the body (12). A coil (22) is fixed in the body (12), and its axis (A-A) extends in a direction essentially orthogonal to the lateral branches (14, 16) of this body (12). A ferromagnetic core (28) is mounted so as to be translatable inside the coil (22), from a rest position to a working position, as an effect of the energising of the coil (22). One end (32) of the core (28), facing towards the first branch (14) of said body (12), has a frustoconical shape essentially complementary to the internal shape (30b) of the formation (30). The frustoconical formation (30) of the first branch (14) of said body (12) is blind and has a planar distal bottom wall (30a).

A method for producing a magnetic core for an electromagnetic actuator of an electromagnetic valve train includes punching a core blank from a soft magnetic metal sheet and reshaping the core blank. The core blank has a base segment with an opening and a plurality of wall segments that extend outwardly from an outer edge of the base segment. The plurality of wall segments is bent in a direction substantially perpendicular to the base segment during the reshaping.

A linear actuator (20, 20, 20) comprises a plunger receptacle (22); a coil (24); a magnetic plunger (26); a magnetic base (28); a return spring (30); and a lock spring (32, 32). The coil (24) is wound about at least a portion of an exterior surface of the plunger receptacle (22). The magnetic plunger (26) is at least partially disposed within a cavity at least partially formed by an interior surface of the plunger receptacle (22) for linear motion along a plunger axis (34). The magnetic base (28) is radially disposed relative to the plunger (26). The return spring (30) is disposed to bias the plunger (26) to a plunger extended position. The lock spring (32, 32) is configured and oriented to lock the plunger (26) in the plunger extended position when power is not applied to the coil (24) but to be attracted to the magnetic base (28) and thereby permit movement of the plunger (26) to a plunger retracted position when the power is applied to the coil (24).

A solenoid valve has a valve body with first and second passages; a coil wound around a coil bobbin; a stator with a third passage; a plunger having a through hole therein; a flux return device; and a spring. When the coil is energized, the plunger is attracted toward the stator such that the plunger closes the third passage, and connects the first passage with the second passage through the through hole in the coil bobbin. When the coil is not energized, the plunger moves away from the stator such that the plunger closes the first passage, and connects the second passage with the third passage. A resilient gasket between the stator and the flux return device reduces vibration from direct contact between the plunger and the stator, being transmitted to the flux return device, thereby reducing vibration and noise.

The invention proposes a proportional electromagnetic actuator comprising: a magnetic casing; an electromagnetic plunger movable relative to the casing and having a first axial half; a first radial gap and a second radial gap which are each formed radially between the plunger and the casing, and which are positioned axially at the first axial half of the plunger. These gaps (26; 28) are formed by concentric annular chamfers (32; 34). The invention also proposes a three-way valve for turbojet oil, which is actuated by an electromagnetic actuator with double chamfered gaps.

The present invention discloses a moving iron core guide mechanism for an HVDC relay, comprising a pushrod, an upper section of the pushrod being located above a yoke plate and fixed with a moving contact assembly, a middle section and a lower section of the pushrod passing through the yoke plate downward, the middle section of the pushrod being fixed with a moving iron core; the moving iron core is located inside a magnetic conductive cylinder of a U-shaped yoke; a lower bushing is fixed inside the magnetic conductive cylinder, and the lower bushing is located below the moving iron core; a lower guide hole running from top to bottom is formed on the lower bushing; and the lower section of the pushrod is always fitted inside the lower guide hole of the lower bushing, and the pushrod is in smooth contact with an inner wall of the lower guide hole. In the present invention, the up-and-down motion of the moving iron core and the pushrod can become easier while the turns of the coil can be maintained; and the production cost can be reduced when the moving iron core and the pushrod are in normal use.

An electromagnetic actuating device (8) is for a variable valve drive, in particular electromagnetic switching valve lever systems. The electromagnetic actuating device comprises a base plate (3), a housing which is secured to the base plate (3) and a coil. The housing is designed as a bracket housing (12) and can form part of the magnetic circuit.

A linear actuator (20, 20, 20) comprises a plunger receptacle (22); a coil (24); a magnetic plunger (26); a magnetic base (28); a return spring (30); and a lock spring (32, 32). The coil (24) is wound about at least a portion of an exterior surface of the plunger receptacle (22). The magnetic plunger (26) is at least partially disposed within a cavity at least partially formed by an interior surface of the plunger receptacle (22) for linear motion along a plunger axis (34). The magnetic base (28) is radially disposed relative to the plunger (26). The return spring (30) is disposed to bias the plunger (26) to a plunger extended position. The lock spring (32, 32) is configured and oriented to lock the plunger (26) in the plunger extended position when power is not applied to the coil (24) but to be attracted to the magnetic base (28) and thereby permit movement of the plunger (26) to a plunger retracted position when the power is applied to the coil (24).