GB828071A - Improvements in electromagnetic relays - Google Patents

Abstract

828,071. Electromagnetic relays. GENERAL ELECTRIC CO. March 21, 1956 [March 21, 1955], No. 8844/56. Class 38 (5). A relay intended for use in circumstances in which when the relay has operated the applied voltage drops but not to the drop-out voltage which is considerably below the pick-up voltage, has means to prevent armature bounce when the armature releases and is arrested by its stop. The arrangement prevents pick-up of the armature by a voltage less than the pick-up value due to armature bounce. As shown, an L-shaped yoke 9 magnetized by a coil 16 pivotally supports at 40 an L-shaped armature 38 biased by a spring 49 connected between a depending armature leg 45 and a notched arm 47 of the yoke 9. The return force of the spring 49, which decreases to almost zero as the armature is attracted towards the pole 24, is adjustable by utilizing a selected notch 48 in the arm 47, thereby determining the drop-out voltage. The released position of the armature, and thus the value of the pick-up voltage, is determined by an adjustable screwed stop 53 engaged by a resilient strip 55 fixed to the armature arm 44, the deflection of the strip 55 being limited by a rigid strip 66 also fixed to the arm, these strips preventing armature bounce. When the armature is attracted, the arm 44 engages the bentover upper end 60 of a contact-carrying blade 47 to separate the contact 61 from a fixed contact 62. In a modification (Fig. 5, not shown), the blade 47 carries a further contact which engages a further fixed contact when the armature is attracted.