GB410282A - Improvements in or relating to pivotal joints - Google Patents

Abstract

410,282. Flexible-unjointed hinges. TRIER, V. A., 38, Felsham Road, Putney, London. Feb. 10, 1933, No. 4103. [Class 65 (ii).] A pair of main members are connected, so that they can move relatively about a common axis, by a rubber or like flexible or resilient bushing interposed between concentric cylindrical surfaces of one of the main members and an intermediate member with a frictional coupling between the latter and the second main member. Means are provided for positively limiting movement of the intermediate member relatively to the first main member, any movement tending to occur between the two main members beyond the limits being permitted by slip between the intermediate member and the second main member. The rubber may be vulcanized to the two members with which it is in contact, or be compressed axially or radially to adhere to both these members. The joint is thus useful for applications in which the normal movement of the parts is relatively small while under some circumstances the movement may be excessive or the mean relative position of the parts may be altered considerably. In its simplest form the joint comprises a rubber sleeve interposed between two concentric cylindrical sleeves, one of which is fixed to or integral with an outer housing or an inner pin, while the other is split to exert a frictional grip, either by its own resilience or by the pressure of the rubber, on the pin or inside the housing, one of the sleeves having a lug, at one or each end, engaging a circumferential slot in the other of such a length as to limit relative movement between the two sleeves to an amount which will not overstress the rubber ; in a modification, both the sleeves may be split for frictional engagement with the respective main members. In place of a lug on one sleeve engaging a slot in the other, both sleeves may be provided with similar slots to be engaged by lugs on an annular member interposed between the main members at one or each end, the combined length of the slots being such as to limit the relative motion of the two sleeves as required. Fig. 5 shows an arrangement in which the outer sleeve is constituted by the housing B while the inner sleeve A is free to rotate on the pin D supported by members F, the frictional coupling of the sleeve A with the members F being effected by friction discs H clamped between flanges A<3> on the sleeve and the members F ; the flanges A<3> are slotted at A<4> for engagement by lugs E on the housing B to limit relative movement between the members A, B, movement within the limits being taken up by distortion of the rubber C. In a form in which the frictional coupling is between a split outer sleeve and the housing, the members F have conical bosses bearing in corresponding seatings in the ends of a thick inner sleeve A, the pin D having no contact with this sleeve ; the outer sleeve has lugs bent down to engage slots in the inner sleeve. In a modification, the pin D itself forms the inner member engaging the rubber, and has conical ends engaging corresponding bearings in the members F; two pins passing diametrically through the pin D engage slots in the ends of the outer sleeve of the joint.