It was the dominant means for front-engine, rear-wheel drive layout cars in the 20th century. The name comes from the French automobile manufacturer Hotchkiss , although other makers, such as Peerless , used similar systems before Hotchkiss. During the early part of the 20th century chain-drive power transmission was the main direct drive competitor of the Hotchkiss system, with the torque tube also popular until the s. Torque reaction effects on a leaf spring in a Hotchkiss drive system Most shaft-drive systems consist of a drive shaft also called a "propeller shaft" or Cardan shaft extending from the transmission in front to the differential in the rear.
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It was the dominant means for front-engine, rear-wheel drive layout cars in the 20th century. The name comes from the French automobile manufacturer Hotchkiss , although other makers, such as Peerless , used similar systems before Hotchkiss.
During the early part of the 20th century chain-drive power transmission was the main direct drive competitor of the Hotchkiss system, with the torque tube also popular until the s.
Torque reaction effects on a leaf spring in a Hotchkiss drive system Most shaft-drive systems consist of a drive shaft also called a "propeller shaft" or Cardan shaft extending from the transmission in front to the differential in the rear.
The differentiating characteristic of the Hotchkiss drive is the fact that the axle housing is firmly attached to the leaf springs to transfer the axle torque through them to the car body. Also, it uses universal joints at both ends of the driveshaft, which is not enclosed. The use of two universal joints, properly phased and with parallel alignment of the drive and driven shafts, allows the use of simple cross-type universals.
In contrast, a torque tube arrangement uses only a single universal at the end of the transmission tailshaft, typically a constant velocity joint , and the axle housing is held fast by the torque tube, which anchors the differential housing to the transmission. In the Hotchkiss drive, slip- splines or a plunge-type[ clarification needed ] ball and trunnion u-joint eliminate thrust transmitted back up the driveshaft from the axle, allowing simple rear-axle positioning using parallel leaf springs.
In the torque-tube type, this thrust is taken by the torque tube to the transmission and thence to the transmission and motor mounts to the frame. Some Hotchkiss driveshafts are made in two pieces with another universal joint in the center for greater flexibility, typically in trucks and specialty vehicles built on firetruck frames. Some installations use rubber mounts to isolate noise and vibration.
Just as important as power transmission is braking. In power transmission, the torque applied to the wheels is countered by an equal and opposite reaction in the axle housing, but in braking, the torque of braking the wheels is equal but in the same direction. In a rear wheel drive car, the braking applied by the rear brakes is just as important as the power transmission, and the problem is the same and is solved in the same manner. Firmly anchoring the axle housing to the leaf springs transfers both directions of torque, both acceleration and braking , to the car body.
There is no connection between the Hotchkiss drive and the modern US suspension-modification company called Hotchkis.
Click here to read more about it. Many rear-drive cars and trucks use a live axle at the rear — that is, the rear axle incorporates the differential and halfshafts into a single rigid unit that moves up and down with the rear wheels. Live axles are cheap and rugged and ensure that the camber of both rear wheels remains constant as the wheels move through their suspension travel. The main drawback of live axles is that they are heavy.
The Hotchkiss Drive | Torque Tube Drive
The diagonal radius arms are discretionary. A torque tube system is a power transmission and braking technology, that involves a stationary housing around the drive shaft , often used in automobiles with a front engine and rear drive, and rear brakes with or without front brakes, which play no part in it. The torque tube consists of a large diameter stationary housing between the transmission and rear end that fully encloses a rotating tubular steel or small-diameter solid drive shaft that transmits the power of the engine to a regular or limited-slip differential. Otherwise, the axle housing would suffer axle wrap, such that the front of the differential would lift up excessively during acceleration and sink down during braking. Its use is not as widespread in modern automobiles  as is the Hotchkiss drive , which holds the rear end in place and prevents it from flipping up or down, during acceleration and braking, by anchoring the axle housings to the leaf springs using spring perches. The Rover 8 had a torque-tube like backbone, lacking a pivoting joint between the transmission and the proper torque-tube to the rear differential casing, to allow suspension travel. The "torque" that is referred to in the name is not that of the driveshaft, along the axis of the car, but that applied by the wheels.