Bump gate
Encyclopedia
A bump gate is a drive-through gate used in rural areas to provide a barrier to livestock
Livestock
Livestock refers to one or more domesticated animals raised in an agricultural setting to produce commodities such as food, fiber and labor. The term "livestock" as used in this article does not include poultry or farmed fish; however the inclusion of these, especially poultry, within the meaning...

 that does not require the driver to exit the vehicle, open the gate, drive through, and then close the gate. By contacting the swinging bump gate with the front of a vehicle and then accelerating, the bump gate is pushed open, allowing the vehicle to pass. This requires some skill to avoid the gate swinging back and striking the vehicle. Accordingly, a bump gate is unsuitable for long vehicles.

The bump gate self closing mechanism consists of two cables mounted on the gate, and also on an elevated crossbar. The gate does not swing on a conventional hinge. Instead it is fastened to cylinders that encircle a post. When the gate swings open, the swivel action causes the cables to raise the gate slightly. After the vehicle passes through, gravity causes the gate to swing like a pendulum
Pendulum
A pendulum is a weight suspended from a pivot so that it can swing freely. When a pendulum is displaced from its resting equilibrium position, it is subject to a restoring force due to gravity that will accelerate it back toward the equilibrium position...

 (parallel to the ground) until it settles in the closed position.

While not a common type of gate, it has been observed in several locations in West Texas
West Texas
West Texas is a vernacular term applied to a region in the southwestern quadrant of the United States that primarily encompasses the arid and semi-arid lands in the western portion of the state of Texas....

.
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK