Patent GB-780875-A (GB)
Title: Machine for assembling resilient bushings of the rubber insert type
IPC: B25B27/28
Filed: 1955-02-11
Abstract: 780,875 Assembling rubber bush mountings. GENERAL TIRE & RUBBER CO. Feb. 11. 1955 [Feb. 15, 1954], No. 4212/55. Class 108(3) A machine for assembling resilient bushings of the kind comprising a tubular rubber sleeve A disposed under radial compression between a rigid outer sleeve B and a rigid tubular core C, comprises a plunger 11 having a core supporting portion at its upper end a tapered expansible pilot 23 attached to the end of the plunger 11, and being normally of a diameter no greater than that of the core supporting portion, so that a core C may be moved over the pilot 23 on to the supporting portion. means 8 for supporting a sleeve B and rubber sleeve A in axial alignment, means for forcing the sleeve A into the sleeve B and for holding the latter in axial alignment with the plunger 11, means for advancing the plunger 11 to cause the pilot 23 to pass through the sleeve A and to place a core C within the sleeve A, and means for expanding the pilot 23 to facilitate the passage of the core B through the sleve A. The supporting means 8 comprises a cross head slidable on rods 9, 9, rigid with the frame of the machine. The cross head 8 is supported by pistons 7, 7 slidable in pneumatic cylinders 6, 6. The sleeve B is supported by a ball catch 19 in the counter bore of the plunger 5 of a hydraulic cylinder 4. The plunger 11 is rigid relative to the frame of the machine. Adjustable stops 21. 21 limit the travel of the cross head 8. In the construction shown in Figs. 1 and 5, the pilot 23 comprises a frusto-conical rubber sleeve disposed between the end of the plunger 11 and nuts 28 threaded on a rod 24 extending concentrically within a bore in the plunger 11. The rod 24 is coupled at its lower end to a diaphragm 31 within a chamber 32. The latter is connected by a pipe 34 to a valve 35. The latter valve which is normally biased by a spring 36, serves to connect the pipe 34 with an exhaust port 37. A roller 44 on an arm 42 pivoted at 41 to the plunger 39, is engageable by a cam 46 carried by the cross head 8 so as to project the plunger 39 into a position in which the valve connects the pipe 34 with a fluid pressure supply port 38. In operation, sleeves A. B, C, are placed in the positions shown in Fig. 1. Pressure is then applied to the cylinder 4 to project the plunger 5 downwardly. The sleeve B is thus forced into engagement with the sleeve A, and the cross head 8 is driven down against pressure in the cylinders 6, 6. As the pilot 23 commences to enter the bore of the sleeve 8, the cam 46 engages the roller 44. and the valve 39 is operated so as to apply fluid pressure to the chamber 32. This draws down the rod 34 and applies compression to the pilot 23, and causes its diameter to increase to a degree comparable with the outer diameter of the sleeve C (Fig. 4, not shown). The plunger 39 remains in fluid pressure supplying position until the cam 46 reaches the position shown in dot and dash lines in Fig. 1. When the cross head 8 is retracted after assembly of the bushing;. the cam 46, instead of deflecting the plunger 39, causes the roller 44 to pivot upwards into the position shown in dot and dash lines. The plunger 11 can thus be retracted from the joint without difficulty. In the construction shown in Fig. 6, the rod 24 is replaced by a fluid pressure supply port 63 which communicates with an annular hollow space 62 within the pilot 23. The chamber 32 is dispensed with, and the port 63 is connected directly to the pipe 34 (Fig. 8, not shown). In operation, when the valve 39 is actuated, pressure is applied directly to the interior of the pilot 23 to cause it to expand as before (Fig. 7, not shown). In Fig. 9, the pilot 23 comprises a metal shell 74 of conical profile, having axially disposed slits so as to enable it to be expanded by axial movement of a member 77. The latter is operated by rods 80 connected to a psiton 79 slidable in a cavity 78 in the plunger 11. The cavity 78 is connected by a bore 63 to the pipe 34 as before.