Patent GB-302259-A (GB)
Title: Improvements in or relating to electro-magnetic apparatus suitable for use as a relay, switch, motor or like device
IPC: H01H51/22
Filed: 1927-09-08
Abstract: 302,259. Creed &. Co., Ltd., Creed, F. G., Storey, W. H., and Salmon, R. D. Sept. 8, 1927. Reciprocating and oscillating machines.- Electromagnetic apparatus such as relays, switches, motors, of the kind in which one or more armatures are mounted to oscillate in relation to one or more magnetic pole-pieces or windings have a part thereof, which is required to be adjustable with respect to the rest of the apparatus, formed as a unit embodying an insulating carrier or casing provided with a pivot pin or the like that is fixed in relation to the unit by being moulded in or formed integrally with the carrier or casing. The carrier plate 1 is of the material known under the Trade Mark " Mouldensite " or of other insulating material that can be softened or melted by heat, becomes hard and rigid at normal temperatures, and cannot afterwards be softened by heat. Two E-shaped laminated polepieces 2, 2<a>, for instance, of the material known under the Trade-name " Stalloy," are permanently fixed therein by moulding and magnetized by a permanent magnet 12, which is held magnetically to them and is slotted at 12<a> so as to ensure its being put in place with correct polarity. The plate 1 is pivoted to a support 3, of the same material as the plate 1, by means of a conical pin 7 in which is disposed a spring 9 anchored to pins 10, 11 on the plate 1 and support 3 respectively, the spring serving to maintain the latter close together and to take up wear of the pin 7. The armature 14 is arranged between the gaps between the inturned ends 2* of the pole-pieces and its spindle 15 is mounted in bearings 16, 17, of which 16 is fixed in the plate 1 and 17 is carried by a plate 18 secured to supports moulded in one piece with the plate 1. The energizing windings 20, 20<a> are placed one on either side of the plate 18 and the leads 21 are carried through the base 4 of the support 3 to terminals 22. To adjust the bias of the armature, the plate 1 is arranged to be rotated about its pivot by a screw 33 in the support 3, the travel being limited by a projection 33<a> working in a groove 35a in another screw. The head of this screw may have index lines and arrows, and a special marking for the central position. A metal or other opaque casing 36 having an inspection window 44 and upper hinged part is secured by a screw 37 to the support 3 and encloses the entire apparatus save the head of the screw 33. A recessed base 38 is provided with spring contacts 39 for engaging the terminals of the support 3 and is secured to the cover by a fixed pin (not shown) and a spring pin 41, means for preventing incorrect assembly being provided. The armature may operate an escapement device, ratchet wheel, or like motor, Fig. 18 (not shown). The pole-pieces 2, 2<a>, in another form, Fig. 19 (not shown), are secured by nuts on pins which are fixed in the plate 1. The armature-spindle inner bearing may be formed in a hole in the plate or moulded in it, and the supports for the. plate 18 may be made separate from the plate and permanently fixed thereto.