TUBE AS 4P7389 - Caterpillar

Illustration 1 g06179887
Left Side of Front Drum
(1) Port "L"
(2) Port "B"
(3) Rear vibratory speed sensor
(4) Port "A"
(5) Vibratory motor (rear)Rear vibratory motor (5) is on the right side of the rear drum. This motor has a straight axis and a fixed-angle swashplate. The front vibratory motor is identical to the rear vibratory motor. The front vibratory motor is on the left side of the front drum.Rubber isolation mounts dampen the vibration which is transmitted from the drum to the machine when the vibratory system is operating.Vibratory speed sensor (3) is at rear vibratory motor (5) and at the front vibratory motor. The vibratory speed sensors provide the input signals to the machine ECM number-two. This information is sent to the machine ECM number-one. The machine ECM number-one uses the input signals from these sensors in the vibratory control logic. This input is also used to operate the vibratory tachometer on the operator display.Each port in the pump housing is identified by a letter or an alpha-numeric designation which is cast into the housing next to the port. The function of each port is as follows:
Port "A" (4) - This port is a system port. When oil is directed into port "A", the motor turns clockwise, as viewed from the output shaft end of the motor. Clockwise motor rotation produces divergent rotation of the eccentric weights. This rotation results in high amplitude operation.
Port "B" (2) - This port is a system port. When oil is directed into port "B", the motor turns counterclockwise, as viewed from the output shaft end of the motor. Counterclockwise motor rotation produces convergent rotation of the eccentric weight. This rotation results in low amplitude operation.
Port "L" (1) - This port is one of two case drain ports on the motor. The second case drain port is labeled as "L1" (not shown). Port "L" of the motor is connected to the return manifold. Port "L1" is connected to port "T1" of the machine valve. Flushing oil from the machine valve is directed into the vibratory motor case through port "L1".
Illustration 2 g06178970
Motor Cross Section
(6) Slipper pad
(7) Piston
(8) Output shaft
(9) Valve plate
(10) Barrel assemblyThe vibratory motor has a fixed-position swashplate and an axial-piston rotating group. The illustration shows an example of this type of motor.When the vibratory system is operating, supply oil from the vibratory pump enters the motor. Supply oil is directed to the inlet port of valve plate (9). The valve plate directs oil into the piston chamber in barrel assembly (10). This pressure forces pistons (7) which are aligned with the inlet port to move out of the barrel assembly. As the pistons are forced out of the barrel assembly, slipper pads (6) slide along the swashplate. This action causes the barrel assembly and pistons to rotate. Since the barrel assembly is splined to output shaft (8), the output shaft also rotates.As barrel assembly (10) rotates, pistons align with the outlet port in valve plate (9). The rotation of the barrel assembly forces oil out