Wheel and axleThe wheel and axle is a simple machine consisting of a wheel attached to a smaller axle so that these two parts rotate together in which a force is transferred from one to the other. The wheel and axle can be viewed as a version of the lever, with a drive force applied tangentially to the perimeter of the wheel, and a load force applied to the axle supported in a bearing, which serves as a fulcrum. The Halaf culture of 6500–5100 BCE has been credited with the earliest depiction of a wheeled vehicle, but this is doubtful as there is no evidence of Halafians using either wheeled vehicles or even pottery wheels.
Drive wheelA drive wheel is a wheel of a motor vehicle that transmits force, transforming torque into tractive force from the tires to the road, causing the vehicle to move. The powertrain delivers enough torque to the wheel to overcome stationary forces, resulting in the vehicle moving forwards or backwards. A two-wheel drive vehicle has two driven wheels, typically both at the front or back, while a four-wheel drive has four. A steering wheel is a wheel that turns to change the direction of a vehicle.
Moment (physics)In physics, a moment is a mathematical expression involving the product of a distance and physical quantity. Moments are usually defined with respect to a fixed reference point and refer to physical quantities located some distance from the reference point. In this way, the moment accounts for the quantity's location or arrangement. For example, the moment of force, often called torque, is the product of a force on an object and the distance from the reference point to the object.
Bronocice potThe Bronocice pot is a ceramic vase incised with one of the earliest known depictions of what may be a wheeled vehicle. It was discovered in the village of Bronocice near the Nidzica River in Poland. Attributed to the Funnelbeaker archaeological culture, radiocarbon tests dated the pot to the mid-fourth millennium BCE. Today it is housed at the Archaeological Museum of Kraków in southern Poland. The pot was discovered between 1974 and 1976 during the archaeological excavation of a large Neolithic settlement in Bronocice, ca.
Loader (equipment)A loader is a heavy equipment machine used in construction to move or load materials such as soil, rock, sand, demolition debris, etc. into or onto another type of machinery (such as a dump truck, conveyor belt, feed-hopper, or railroad car). There are many types of loader, which, depending on design and application, are variously called a bucket loader, front loader, front-end loader, payloader, high lift, scoop, shovel, skip loader, wheel loader, or skid-steer.
Steering wheelA steering wheel (also called a driving wheel (UK), a hand wheel, or simply wheel) is a type of steering control in vehicles. Steering wheels are used in most modern land vehicles, including all mass-production automobiles, buses, light and heavy trucks, as well as tractors. The steering wheel is the part of the steering system that is manipulated by the driver; the rest of the steering system responds to such driver inputs.
WheelwrightA wheelwright is a craftsman who builds or repairs wooden wheels. The word is the combination of "wheel" and the word "wright", (which comes from the Old English word "wryhta", meaning a worker or shaper of wood) as in shipwright and arkwright. This occupational name became the English surname Wright. It also appears in surnames like Cartwright and Wainwright. It corresponds with skilful metal workers being called Smith. These tradesmen made wheels for carts (cartwheels), wagons (wains), traps and coaches and the belt drives of steam powered machinery.
Simple machineA simple machine is a mechanical device that changes the direction or magnitude of a force. In general, they can be defined as the simplest mechanisms that use mechanical advantage (also called leverage) to multiply force. Usually the term refers to the six classical simple machines that were defined by Renaissance scientists: Lever Wheel and axle Pulley Inclined plane Wedge Screw A simple machine uses a single applied force to do work against a single load force.
Differential (mechanical device)A differential is a gear train with three drive shafts that has the property that the rotational speed of one shaft is the average of the speeds of the others. A common use of differentials is in motor vehicles, to allow the wheels at each end of a drive axle to rotate at different speeds while cornering. Other uses include clocks and analog computers. Differentials can also provide a gear ratio between the input and output shafts (called the "axle ratio" or "diff ratio").
Tractive forceAs used in mechanical engineering, the term tractive force can either refer to the total traction a vehicle exerts on a surface, or the amount of the total traction that is parallel to the direction of motion. In railway engineering, the term tractive effort is often used synonymously with tractive force to describe the pulling or pushing capability of a locomotive. In automotive engineering, the terms are distinctive: tractive effort is generally higher than tractive force by the amount of rolling resistance present, and both terms are higher than the amount of drawbar pull by the total resistance present (including air resistance and grade).