Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
  • H01H50/00—Details of electromagnetic relays
  • H01H50/02—Bases; Casings; Covers
  • H01H50/023—Details concerning sealing, e.g. sealing casing with resin
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
  • H01H50/00—Details of electromagnetic relays
  • H01H50/02—Bases; Casings; Covers
  • H01H50/026—Details concerning isolation between driving and switching circuit

Definitions

• the invention relates to an electromagnetic relay com- prising the following features: a base member which carries an electromagnetic system including a coil, a core assembly and an armature and constitutes part of a switching chamber, a contact system arranged in the switching chamber and having at least one fixed contact and one movable contact spring carrying a switching contact and adapted to be actuated by said armature, terminal conductors for the contacts and for the coil, - a casing enclosing the electromagnetic system and the switching chamber.
• the invention relates to a method of making such a relay.
• Relays usually are constructed in such a manner that a header, constituting a casing bottom, has the various components of the relay mounted thereon, and finally a casing cap is slid over the arrangement so that a closed casing results.
• the coil winding and the contact system are spatially interconnected so that contact-damaging outgassing from the coil may impair the contact surfaces. While certain contact coatings may be burnt away by the switching current in case of power relays, this does not hold for miniature relays for switching small currents. It is thus desirable to spatially separate the coil region from the contact system region and to avoid outgassing from the coil, respectively.
• this object is met in that the switching chamber is closed by a covering cap and in that the casing is constituted by shape-defining embedding of the stationary parts of the electromagnetic system and by at least partial embedding of the base member and the covering cap in insulating material, with the terminal conductors being passed to the outside through a casing wall.
• the relay according to the invention meets the object in particularly advantageous manner since no additional parts need be employed for noise encapsulation. Partial molding or casting is usual anyway due to the winding outgassing, so that no additional expenditure arises and assembly is facilitated.
• a method of making a relay according to the invention consists in that the switching chamber is sealed towards the outside by a covering cap before the stationary parts of the electromagnetic system, the covering cap and the base member are embedded in plastics material in part or completely.
• the relay is designed in particular- ly advantageous manner when the covering cap cooperates with the base member.
• the base member fixing the relay components during assembly thus also fulfils the function of a sealing wall.
• a simple development of the relay according to the invention also results from the fact that no stable header has to be provided as in conventional relays, but that the necessary mechanical stability is achieved according to the invention by embedding in plastics material.
• the high stability is significant as the often low air gap and contact spacings are sensitive to distortion of the system.
• the embedding provides for a favorable temperature behavior.
• a relay according to the invention minimizes the number of parts and thus also the assembly costs.
• Figs. 1A to C show schematic representations of a relay according to the invention and the assembly thereof
• Figs. 2A to D show a relay according to the invention in a concrete embodiment.
• Figs, la to c schematically illustrate the manufacturing steps for making a relay according to the invention.
• an electromagnetic system consisting of a coil 1, a core assembly 4 and an armature 5 with a resetting spring 6, as well as a contact system 7 consisting of a contact spring 10 connected to armature 5, of two fixed contacts 8 and a switching contact 9 that is mounted to contact spring 10.
• a switching chamber 18 On the side of electromagnetic system 7 having armature 5 mounted thereon, there is formed a switching chamber 18. In the latter, there is also provided contact system 7.
• switching chamber 18 is closed by a covering cap 12.
• Cap 12 positively abuts a yoke of core assembly 4, a sealing-wall -establishing extension 13 of a coil body flange 14 and laterally, not shown in the drawings, abuts coil body flange 14, such that the arrangement with contacts 8 and 9, contact spring 10, armature 5 and resetting spring 6 is sealed completely to- wards the outside (Fig. IB) .
• Extension 13 is designed mechanically such that it is adapted to fix contacts 8 and 9 as well as terminal conductor 11 thereof, respectively, but does not offer sta- bility therebeyond. It is also conceivable to have an arrangement in which extension 13 serves only for sealing switching chamber 18.
• the assembly of electromagnetic system 16, contact system 7 and covering cap 18 has plastics material molded therearound, so that the molding forms a casing 15, with the exterior ends of terminal conductors 11 being left free.
• Molding 15 effects the firm connection of all relay parts and takes up the forces acting in particular on the terminal conductors 11 of the relay. In addition thereto, it effects acoustic encapsulation of the relay.
• covering cap 12 may constitute a part of the casing that has no plastics material molded therearound.
• Figs. 2A to 2D reveal the construction of a relay according to the invention in a concrete embodiment as well as the assembly thereof.
• the relay is preassembled in known manner, with the design of an armature and a contact system being of subordinate signif- icance for a relay according to the invention, and these parts being thus not shown here, either.
• Fig. 2A basically shows such a relay in a perspective view.
• the movable parts are mounted on an extension 33 of coil body flange 34 and on a mounting header 36 molded onto coil body flange 34 and extension 33.
• a covering cap 32 formed of plastics material according to Fig. 2B is applied.
• said covering cap 32 is applied over the movable parts of the relay in such a manner that it positively abuts extension 33 and coil body flange 34 and constitutes a closed switching chamber together with the same.
• the relay according to Fig. 2D is formed that is completely encapsulated except for terminal conductors 31.

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• Physics & Mathematics (AREA)
• Electromagnetism (AREA)
• Electromagnets (AREA)
• Switch Cases, Indication, And Locking (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=7904865

Family Applications (1)

Country Status (2)

Cited By (1)

Families Citing this family (3)

Citations (5)

Family Cites Families (3)

• 1999
  • 1999-04-16 DE DE1999117338 patent/DE19917338C2/de not_active Expired - Lifetime
• 2000
  • 2000-04-14 WO PCT/EP2000/003421 patent/WO2000063937A1/en active Application Filing

Patent Citations (5)

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