TORQUE CONVERTER is an apparatus for transmitting power automatically from an engine or other source of power to a secondary shaft, the torque and speed of the secondary being variable according to the load between wide limits. It was in vented by George Constantinesco. The principle of the torque converter consists in dividing an oscillatory movement derived from a primary shaft which is driven by the engine, into two component oscillatory motions of the same frequency. One of these components oscillates an inertia device and the other oscil lates unidirectional driving devices mounted on the secondary. The alternating impulses received by the secondary through the unidirectional devices are thus rectified into continuous rotation of the secondary.
Such unidirectional driving devices, shortly named "rectors," comprise any such devices which will drive in one direction and be free in the opposite direction. The rectors perform what may be termed a "mechanical valve ' action very much like an ordinary hydraulic valve or electric valve, or rectifiers allowing the flow of energy only in one direction. The left hand figures of each of the two pairs of illustrations, depict two phases of an experi ment which will illustrate the principle of the torque converter. The operations performed by each hand are then translated in the right hand figures into the functions of a "torque con verter" in which the lower hand is replaced by a connecting rod moved by a crank, and the upper hand by two rectors which are connected to the secondary shaft where the resistance occurs.
A slow oscillatory motion at the "drive" merely swings the mass to and fro, the fulcrum of oscillation remaining at the point of resistance. If a rapid os cillatory motion is applied at the "drive" the inertia of the mass will oppose its motion, and the resistance is overcome. The upper hand moves then, almost as if it were driven directly, the fulcrum being right down at the mass. Such a combination is a four dimensional mechanism as
the element "time" is essential to its performance. The ordinary rules of static mechanics do not apply to the torque converter, and it is only by the consideration of the elements "time" and "mass" that the behaviour of the converter can be explained.
The torque converter has many possible applications to traction problems and industry in general as in transmission for applying the power of internal combustion engines, turbines, electromotors and prime movers which lack flexibility, to uses where wide and unexpected fluctuations in the load occurs. The torque converter provides automatically for the adjustment of the speed and torque on the secondary, no matter how the resistance changes or fluctu ates between very wide limits, while the prime mover continues to run steadily, with very little variation, at its most efficient torque and speed. In practice the inertia systems and the rectors are so arranged that the various parts balance each other dynami cally as much as possible so that no vibrations are imparted on the casting of the machine.
A petrol (gasolene) engine may be combined with mechanism so as to form one single unit ; the only control required being the throttle of the engine. Vehicles driven by such units have no clutches nor gear change boxes. By opening wide the throttle of the engine the vehicle will accelerate from rest and attain a cer tain maximum speed on the level. When a hill is encountered, the vehicle slows down while the tractive force increases auto matically according to the gradient. For example, a vehicle fitted with a torque converter may travel at 4o m. per hour on a level or climb at i o m. per hour a gradient of one in four, while the torque and the speed of the engine remains the same in both cases.