Patent GB-296776-A (GB)
Title: Improvements in flexible pivotal joints
IPC: F16D3/76
Filed: 1928-07-10
Abstract: 296,776. Thiry, L. Sept. 9, 1927, [Convention date]. Addition to 243,679. Universal joints and like couplings.-The improvements in the flexible pivotal joint according to the parent Specification comprise using a compressed elastic element which is of an elliptical or like shape in cross section, as shown, for example in Fig. 1, in order to prevent relative slipping of the parts of the joint serving for the transmission of power, and in making the contact surfaces of the flexible ring with the inner and outer tubes of a tapered, zig-zag or like shape, as shown in Fig. 9, in order to resist axial stresses. The flexible ring members may also be combined with elastic washers that are subjected to an initial deformation, so as to resist the stresses parallel with the axis; such an arrangement is shown in Fig. 12. To increase the pressure of the elastic ring near the ends of the pivot it is made thicker at the ends than at the middle before deformation, as shown in Fig. 3, and stiffness to axial stresses is obtained by using rings which, in the free state, have an undulated outline, as shown in Fig. 8. Increased resistance to axial stresses is also obtained by providing a joint, having two elastic elements forced axially against one other. In this arrangement the elastic sleeves 5, 6, Fig. 10, are placed between tubes 7 8 each having a shoulder at one end. By moving the inner linings towards one another through the distance D the elastic sleeves are deformed in an axial direction and the joint stiffened axially, suitable stops or rivets serving to maintain the joints apart in position. The elastic ring may be placed in the remaining space D between the rings, and suitable stops or elastic material placed at the ends of the deformed rings. As shown in Fig. 12, elastic rings or discs 12, 13 subjected to deformation are placed at the centre of the joint, these discs being placed between metallic washers 16, 17, 18 held between outer tubes 19 20 and inner tubes 21, 22 after which the tubes 23 , 24 are crimped or upset by suitable means. The rings 12, 13 may also be of tapered shape, and, as described in a modified construction, they may be placed at the ends. According to Fig. 13, deformed rings 25 of indiarubber are placed between the ends of the deformed elastic ring 26 and the end plates 27, 28 of the shackle of a vehicle suspension spring. The blocks 2, 3 may be made in a single ring surrounding the spring plate. The deformation of the elastic material is stated to be facilitated by employing tools that are operated at high speeds for the insertion purpose. The Specification as open to inspection under Sect. 91 (3) (a) comprises also a construction for the sliding and pivotal joint for the ends of motor vehicle springs is shown in Fig. 2 (Cancelled). The main spring plate 1 is held between elastic blocks 2, 3 which have been deformed by insertion in boxes (not shown), connected to the vehicle frame. The fibers are shortened along the axis OX, that is perpendicular to the main spring plate, and lengthened along the axis OY extending transversely to the plate. This arrangement is stated to give great mobility according tc the axis OZ parallel to the said plate, and to provide for lengthwise displacements of its end 4. The application to joints for shock absorbers, cardan joints, and brake control gears is also referred to. This subject-matter does not appear in the Specification as accepted.