Patent GB-699083-A (GB)
Title: Improvements in or relating to throttle control devices for internal combustion engines
Inventor: PARKER SYDNEY MACDONALD
IPC: F02D29/02
Filed: 1950-06-30
Abstract: 699,083. Change-speed gearing. AUTOMOTIVE PRODUCTS CO., Ltd. Aug. 27, 1951 [June 30, 1950], No. 16441/50. Class 80 (ii). The opening and closing movements of the throttle valve of a vehicle engine are limited during gear changes by means of two stops each operated by a servomotor, one or the.other of the servos being energised during a gear change to move its stop into the path of a member movable with the throttle. In the form shown in Fig. 1, a gear lever 29 operates, through rod 27 and lever 28, a plunger valve 26 controlling supply of pressure liquid to a double-acting servo 24 which effects gear changes through rods 22, 23 actuated through bell-crank levers by cams on the servo piston 25, the lever 28 being pivoted on a link 31 which is moved through a bell-crank lever 32 actuated by a cam surface on piston 25 so that valve 26 follows-up the piston and moves to its closed middle position when the gear change is completed. Two switches 35, 36, actuated by valve 26, control two solenoids 50, 51, the armatures of which have slots 54 embracing a pin 48 on an arm 44 secured to the throttle spindle 39. The accelerator is connected through cable 42 to an arm 41 loose on spindle 39 but connected to arm 44 through resilient means normally acting as a rigid connection. Normally, the two switches 35, 36 are open and the two slots 54 coincide to permit the full normal range of movement of the throttle. When lever 29 is moved to the right (or left) for upward (or' downward) gear changes, switch 35 (or 36) is closed and solenoid 50 (or 51) energised to move its armature to the right (or left), the left (or right) end of its slot then limiting movement of pin 48 to the left (or right) and so preventing opening (or closing) of throttle beyond, say, oneeighth (or three-eighths) open position. As the gear change is completed, the switch is opened. A switch 56, in series with switches 35, 36 and controlled by rod 27, is maintained closed for all forward gears but is opened for neutral and reverse. In the arrangement shown in Fig. 6, an engine-suction servo (not shown) is energised to disengage the engine clutch and a single-acting engine-suction servo 82 is energised to move a stop 67 into the path of a pin 66 on a plate 65 secured to the throttle spindle 64 so as to reduce the throttle opening, whenever a gear is disengaged, while upon engagement of a gear the servo 82 is de-energised, the clutch servo remains energised and a double-acting enginesuction servo 83 is energised to move a stop 68 into the path of pin 66 so as to increase the throttle opening unless and until the driving member of the clutch overtakes the driven part. The plate 65 is connected to the accelerator-operated cable 71 through a lever 70 and a resilient but normally-rigid telescopic link 69. A control valve unit has two solenoids 114, 115 with spring-pressed armatures carrying valve heads 116, 117 which normally close the ends of a central bore 98 connected by a pipe 107 through a non-return valve 108 to the engine inlet manifold 200 and connected to a vacuum reservoir 63 through pipe 109. Chambers 106, 100 adjacent the solenoid 115 are connected respectively to atmosphere through ports 120 and through a pipe 111 to the servo 82 and to the left-hand' chamber 94 of servo 83, while chambers 105, 99 adjacent the solenoid 114 are connected respectively to chamber 100 and through a pipe 110 to the right-hand chamber 95 of servo 83. A pipe 112 leads from chamber 99 to the clutch servo. A two-way switch 62 is actuated by cam strips 123 on a lever-operated rod 124 adjacent the steering column 121, the rod being slidable to select a gear-shift bar and turnable to displace the selected shift bar; or the switch may be actuated, through a lever, by individually-adjusted cams on the rod 124, one cam for each speed. Normally, both solenoids are deenergised, so that pipes 110, 111,.112 are open to atmosphere, both stops 67, 68 are withdrawn, 'and the clutch is engaged. When the gears are disengaged, switch 62 acts to energise solenoid 115, chambers 99, 100 ,are shut off from atmosphere and suction is applied to pipes 110, 111, 112. As suction now acts on both sides of servo 83, stop 68 is not moved but stop 67 is moved to reduce the throttle opening, and the clutch servo is energised to disengage the clutch. As a gear is engaged, switch 62 is reversed, solenoid 115 is decenergised, and stop 67 is retracted. The circuit of solenoid 114 includes, however, contacts which are closed only when the clutch is disengaged and its driving part is revolving slower than its driven part, so that, if this latter condition now obtains, the solenoid 114 is energised, whereby suction is applied to pipes 112, 110 only, to maintain the clutch disengaged and to cause the stop 68 to be projected to open the throttle. When the driving part overtakes the driven part, the circuit of solenoid 114 is broken, so that the stop 68 is retracted and the clutch engages. Specification 695,465 is referred to.