GB811356A - Improvements in seals for bearings - Google Patents

Abstract

811,356. Sealed bearings. BURTONWOOD ENGINEERING CO. Ltd. Feb. 27, 1957 [May 12, 1956; July 25, 1956], Nos. 14830/56 and 23005/56. Class 12 (1). [Also in Group XXVI] A seal for a ball or roller bearing comprises a ring 11, Figs. 1 and 2, of rubber or like material, which has one edge entering a groove 6 formed in one race 7 and the other edge formed as a lip 5 bearing on the other race 8, and a reinforcing ring 12 which is bonded to or embedded in the ring 11 and has one of its edges disposed adjacent that edge of the ring 11 entering the groove 6, there being in the unreinforced part of the ring 11 at least one annular zone 14, Fig. 1 or 16, Fig. 2, of less thickness than the remainder of that part to provide a resilient hinge area about which the lip 5 may be displaced axially. The reinforcing ring 12 may be of metal or moulded plastic material. Stiffness is provided in the embodiments shown in Figs. 1 and 3 by annular corrugations 13 and 17 respectively and in each the reinforcing member contacts the locating groove 6 in the outer race 7. Alternatively, corrugations may be radial or both radial and annular. In the construction shown in Fig. 2, the reinforcing member 12 is stiffened by beading or folding its outer edge, the reduced thickness portion 16 allowing for the flexing of the lip portion 5 against the arcuate contacting part of the inner race. In Figs. 1 and 3, flexibility is provided by forming necks 14 and 19 respectively nearer the inner margins of the resilient annular elements. The plane containing the section of minimum thickness is set at an angle in Fig. 3 and the inner edge of the reinforcement 17 lies at the outer boundary of the portion 18 of reduced thickness. Fig. 4 shows a further modification in which the neck portion 23 is adjacent the inner boundary of the reinforcing member 21 which is rolled or swaged to provide a partly embedded arcuate section 22 to abut against the outer race 7. The median plane of the area of reduced thickness, or when there is more than one such area as in Fig. 4, of that area nearest the sealing lip, may be parallel with or contained by the median plane of the seal as a whole or at an angle thereto as in Fig. 3. The sealing lip may be moulded so that when unstressed it extends out of the plane of the annular member towards the bearing, or the reinforcement may be formed with a notched edge to provide teeth having a slight axial set towards the face to be sealed. The reinforcing ring may also be apertured to provide a key for the rubber covering. Alternative arrangements are described in which the sealing lips contact the outer races and the rigid parts are secured in grooves in the inner races. The seals may be of different colours at opposite sides of the bearing to indicate the respective ends of, for example, a semi-thrust bearing. Self-sealing lubricating apertures may be provided in the seals. The second Provisional Specification states that the reinforcing element need not be embedded in or bonded to the rubber-like element.