Electromagnetic relay with pivotable armature

In an electromagnetic relay comprising:

• a base mounting an electromagnet and a contact assembly;
• said contact assembly comprising a fixed contact on said base and an elongated movable spring carrying at its one end a movable contact engageable with said fixed contact and supported at the other end to said base;
• said electromagnet including a core having first and second ends, a coil wound about said core, a yoke connected at its one end to the first end of the core and extending parallel to said core, and a generally L-shaped armature having a first leg extending along the yoke and a second leg extending over the second end of said core to define therebetween an air gap;
• said armature rockable with its inside angle pivotally supported against an edge at the other end of said yoke for pivotal movement in response to the energization and deenergization of said coil between an attracted position in which the second armature leg is attracted to said second end of the core and a reset position in which the second armature leg is spaced away from the first end of said core;
• said first armature leg being operatively connected to said movable spring through an electrically insulative actuator so as to drive the movable spring in a direction of engaging the movable contact with said fixed contact against a return bias applied to the armature as said armature moves to its attracted position in response to the energization of said coil, said return bias causing the armature to move back into said inoperative position for disengaging the movable contact from said fixed contact upon deenergization of the coil;
• said relay characterized in that a stationary retainer means is provided on the base adjacent the angled portion of the armature to loosely engage that angled portion between the edge of the yoke and the retainer means for preventing said inside angle of the armature from departing beyond a predetermined allowable distance from the edge of the yoke;
• that said movable spring is self-biased away from said fixed contact to thereby produce said return bias which is transmitted to said armature through said insulating actuator and said first armature leg while holding said insulative actuator between said movable spring and said first armature leg, and
• that a fulcrum projection is provided on the base to receive the free end of the first armature leg when the armature is moved to its reset position, said actuator abutting against the first armature leg at a point inwardly of said fulcrum projection along the length of the first armature leg for transmitting to the armature said return bias as a torque which causes said armature within said allowable distance from the edge of the yoke to pivot about the fulcrum projection in a direction of urging said inside angle of the armature toward the edge of said yoke close enough so that upon the energization of the coil the inside angle of the armature can be firstly attracted to the edge of the yoke before the second armature leg is attracted to the core to substantially drive the movable spring by the first armature leg into contact with the fixed contact, whereby the armature can have its inside angle in exact coincidence with the edge of the yoke prior to being pivoted to the attracted position.