Patent GB-660625-A (GB)
Title: A method of and apparatus for assembling an elastic tubular rubber insert under radial compression between an outer rigid tube and an inner rigid core
IPC: B25B27/28
Filed: 1949-07-20
Abstract: 660,625. Assembling rubber bush mountings. GENERAL TIRE & RUBBER CO. July 20, 1949. [Nov. 26, 1948] No.19148/49. Class 108(iii). A method of assembling a tubular elastic rubber insert A between an outer rigid tube B of smaller internal diameter, and an inner rigid core C, Fig. 7, of greater internal diameter, than that of the insert, comprises forcing the insert by pressure applied axially adjacent its periphery through a funnel-shaped guide 29 into the tube B, limiting the radial inward expansion of the insert during such axial movement, and entering the core C into the insert behind a tapered pilot 50 from the end of the tube opposite that into which the insert was forced. The funnel-shaped guide 29 is axially slidable within a housing tube 22 against a spring 26 until it engages a stop 27. The tube B is clamped during the operation between the inner end of the funnel 29 and a cross head 15 slidable on guide rods 13 rigid with the housing 22. The cross head 15 is connected by rods 16, 17 to a cross head 18 rigid with the piston rod 19 of a pneumatic cylinder 8. The pilot 50 has a reduced stepped end-portion (Fig. 9, not shown) by which it is fitted on one end of the core C (which is of tubular form), and the bored-out end of the extension of a piston rod 21 of a pneumatic cylinder 9. A plunger 41 is carried by the piston of a third pneumatic cylinder 7 and is normally retracted to the position of Fig. 7. Operation. The insert A is placed in the mouth of the guide 29 as in Fig. 3 and pressure is applied to the cylinders 7, 8 to project the plunger 41 concentrically into the housing 22 to the position shown in Fig. 3, in which a reduced end-portion 42 of the plunger engages the bore of the insert A. A shoulder 43 on the plunger 41 engages a portion of the end face of the insert. The latter is also engaged by a tubular plunger 38 which is normally slidable between limits defined by stops 36a and 36b within a tubular member 36 rigid with the housing 22 but is held in the position shown in Fig. 3 by an enlargement 44 on the plunger 41. Pressure in the cylinder 8 now increases (by means described below) and the cross head 15 acts through the tube B against the member 29 displacing it against the spring 26 so that the insert A (which is held at one side by the fixed plungers 41, 38) is projected through the funnel and into the tube B, Fig. 4 (not shown). The plunger 41 is then retracted and air pressure is applied to the cylinder 9 to project the pilot 50 and insert the core C. Pneumatic system. Air is supplied from a reservoir 68 (Fig. 7) to valves 59, 60, 70, which control the cylinders 7, 8, 9 respectively. Each valve 59, 60, 70 comprises a pair of pistons 72, 73 (Fig. 8) rigid with a stem 74 and slidable in a bore 71 of the valve housing. Further pistons 77, 78 rigid with the stem 74 slide in counterbores 75, 76, the outer ends of which are connected with a supply pressure line 65 to the reservoir by ducts 87 in the housing. The piston assembly is however biassed to the right by a spring 84. In this position the pressure line 65 is in communication with a port 83 and a further port 82 is in communication with an opening 80 to exhaust. A further opening to exhaust 81 is closed by the piston 73. The pressure in the counterbore 75 may be released to exhaust through an opening 88 by the action of a valve 89 which is normally closed but is opened on energization of a solenoid 62. When this occurs the piston assembly moves to the right and so connects the port 83 to exhaust and port 82 to the pressure line. The port 83 of each valve 59, 60, 70 is connected to the piston-rod side of the respective cylinder 7, 8, 9, so as to retract the piston rod when the respective solenoid is not energized. The other end of each cylinder is connected to the respective port 82. The ports 82 of the valves 59, 60 are connected by a valve 103 which opens when the pressure in the left-hand end of cylinder 7 reaches a predetermined amount. Variable flow control valves are provided at 94, 96, 98, 100 and check valves 66, 67 are provided in the main pressure line. The solenoid 62 of the valve 60 is connected to power supply lines 105, 106 through two spaced manually-actuated switches 10, 11. One side of each solenoid 61, 101 of the valves 59, 70 is connected to the line 106. The other side of the solenoid 61 is connected to one fixed contact 111 of a two-way switch 110, the moving contact of which normally engages the contact 111 and is connected with the power line 105. The other fixed contact 114 of the switch 110 is connected via a micro-switch 116 with the solenoid 101. Operation of the pneumatic system. When the switches 10, 11 are depressed, power is supplied to the solenoids 61, 62 which causes actuation of the piston rod 19 and plunger 41. When the head 42 of the rod 41 enters the insert A pressure rises in the cylinder 7 and lifts the valve 103 thus raising the pressure in the cylinder 8. After a predetermined degree of resulting movement of the piston rod 19, a stop 113 on the rod 17 actuates the moving contact of the switch 110 so that it is connected and disconnected with the fixed contacts 114 and 111 respectively. Power is thus withheld from the solenoid 61 and the valve 59 is reversed so that the plunger 44 is retracted. A stop 44 on the plunger 41 then engages a moving element of the switch 44 to complete the circuit through the solenoid 101 which causes reversal of the valve 70 and projection of the piston rod 21 and pilot 50 through the insert A and tube B. When the operator breaks either or both switches 10, 11 the pistons of the cylinders 7, 8, 9 return to their initial positions. Specification 660,626 is referred to.