FLUESSIGKEITSFILTER

1449853 Oil filter GENERAL MOTORS Ltd 15 Aug 1974 [6 Sept 1973] 41970/73 Heading B1D An I.C. engine oil filter of the screw-on, integral housing type has a pleated paper filter element 12 with pleats individually sealed at both ends mounted on a perforate tube 14 which extends beyond the element at end 15 where sealing ring 16 seals between the element and housing end plate 3, the other end of the element receiving the dished centre 19 of a spring plate 17 whose arms 18 press the element upwards to compress ring 16. Ring 16 may have a radial flange overlying inlets 8 to act as a non-return valve. A pressureoperated by-pass valve may be mounted at either end of tube 14. End plate 3 is welded to annular disc 4 which is seamed to metal housing 1. The inner fold lines at the ends of filter element 12 are flattened at 23 (Fig. 4, not shown) to present continuous surfaces engaging shoulder 20 and ring 16. In manufacture, spring plate 17 receives adhesive on shoulder 20 and is dropped into the housing, followed by element 12 which is already mounted on tube 14. Circumferential bead 2 in the housing wall centres the element. The assembly then enters an oven to cure the resin impregnating element 12, ring 16 is applied to the projecting end of tube 14 and end plate 3 fitted. The filter design facilitates manufacture on an automatic assembly line.