BOOM AR-VARIABLE ADJUSTABLE 1584151 - Caterpillar

Illustration 1 g06132307
Inside Drum Assembly
(1) Vibratory motor
(2) Eccentric weight
(3) Shaft
(4) HousingThe drum assembly contains eccentric weight (2). The weight is located inside housing (4). The eccentric weight is connected to splined shaft (3). Vibratory motor (1) is splined to the shaft of the eccentric weight.When the vibratory system is operating, vibratory motor (1) rotates eccentric weight (2) by rotating splined shaft (3). Since the center of gravity of the eccentric weight is not centered on the shaft, rotation of the eccentric weight causes the drum to vibrate.Internally, eccentric weight (2) has a hollow pocket. The pocket is partially filled with shot. When the vibratory system is operating at low amplitude, vibratory motor (1) rotates the eccentric weight counterclockwise. This direction of rotation captures the shot in the pocket on the "light" side of the eccentric weight. This action brings the center of gravity of the weight closer to the center of splined shaft (3), reducing the amplitude of the vibration.When the vibratory system is operating at high amplitude, vibratory motor (1) rotates shaft (3) clockwise. In this case, the shot is captured in the pocket on the "heavy" side of eccentric weight (2). This action takes the center of gravity of the weight farther from the center of the splined shaft, increasing the amplitude of the vibration.