Patent GB-757713-A (GB)
Title: Improvements relating to engine brake arrangements
IPC: F01L13/00
Filed: 1953-06-12
Abstract: 757,713. Regulating. DAIMLER-BENZ AKT.-GES. June 12, 1953 [June 16, 1952], No. 16257/53. Class 7(6) [Also in Group XXXI] In an arrangement for braking an I/C engine comprising means manually controllable through a linkage, having an interconnection with the accelerator linkage, for throttling the exhaust, the linkage being interconnected with the clutch control linkage so that on either declutching or accelerating the exhaust throttle is opened, the interconnections are such that upon operation of the clutch linkage during braking, the accelerator linkage is adjusted to a position which ensures idle running of the engine. In Fig. 1, the exhaust throttle 6 is operable by a hand lever 3 which is also connected via a bell-crank 12 to an arm 16 freely rotatable about the pivot 14 of the clutch pedal 8. A lug 17 picks up the arm 16 when the pedal 8 is depressed. A lug 12<SP>1</SP> on the bell-crank 12 is engageable with stops 23, 24, on a rod 19, connected to the accelerator pedal 7 and with lost motion to the fuel supply regulating lever 22 of a fuel injection pump 21. The throttle' 6 is loaded into open or closed position by an over-centre spring 30. In operation, the hand lever 3 may be set (as shown) to close the throttle 6. Depression of the accelerator pedal 7 then operates through projection 24 and bell-crank 12 to. take off the throttle 6. Depression of the clutch pedal 8 acts through crank 12 in the same way. In the " throttle closed " position of the mechanism, the rod 19 is held in a position corresponding to " engine idling", by a lever 27 loaded by a spring 29 into engagement with a stop 25. When the hand lever 3 is moved to the " throttle open position, the projection 23 is engaged by the lever 12 so as to move the rod 19 into a position in which the stop 25 permits the spring 29 to relax. Its coils then engage solid and it is able to transmit thrust from a Bowden cable 28 when the latter is operated to shut off the fuel supply by raising the lever 27. This permits the rod 19 to return beyond the engine-idling position by the action of a spring 22a (which is weaker than the spring 29). In the arrangement of Fig. 3, the lever 3 acts on the throttle 6 via a multi-arm lever 34. Arms 34a, 34b of the arm 34 are engageable respectively by the clutch pedal 8 and an arm 39a of a lever 39 connected to the accelerator pedal 7. A stop 37 is adjustably mounted between the arm 34b and the arm 39a. The other arm 39b of the lever 39 is connected by rod 41 to the fuel supply control (not shown). Movement of the lever 39 in a counter clockwise direction is limited by a stop 45 on a lever 43 connected to a control 44 for adjusting the fuel supply for idle-running or for cutting off the fuel supply. In the arrangement of Fig. 4, the hand lever 3 (not shown), acts via rod 2 and linkage 31, 32 on the exhaust throttle 6 and via a link 11 on a bell-crank 47. A double-armed lever 50 is rigid with the bell-crank 47, but a lever 51 is mounted for free rotation about the common axis of crank 47 and lever 50. The lever 51 is interposed in the linkage connections between the accelerator pedal 7 and the fuel-supply regulator 22. An adjustable stop (not shown) limits the movement of the hand lever 3 in the throttle-open position shown. This determines the position of arm 50a of the arm 50 in a position corresponding to engine-idling. If the lever 3 is moved a little in the direction towards throttleclosing, the movement is insufficient to move the throttle 6 into closed position against its over-centre spring 30, but the arm 50a is moved into a position which corresponds to fuel supply being shut off completely. When the lever 3 is moved fully over to close the throttle 6, depression of the clutch 8 and accelerator 7, will open the throttle 6 by acting on arm 47a of bell-crank 47 and arm 50b of lever 50, respectively. The engine brake may be combined with means for switching off the ignition. Reference has been directed by the Comptroller to Specification 734,058.