Archive for May, 2010

Torque Motor

{0 Comments}

Torque Motor

As shown in Fig. 11.8, a torque motor consists of an armature, two coils, and two pole pieces. The coils are wrapped on the armature, and the armature is mounted such that the ends are positioned in the center of the air gap between the upper and lower pole pieces. Permanent magnets are incorporated in …

Read More…

Hydraulic Oscillating Actuator

{0 Comments}

Hydraulic Oscillating Actuator

There are some applications in which continuous rotation is not needed. Two examples are industrial mechanisms performing pick-and-place operations and heavy-duty, large-payload robots. Vane motors with one or two vanes are used for limited-rotation applications. The single-vane unit can rotate 280°, and the double-vane 150 to 160°. The direction of rotation is determined by a …

Read More…

Hydraulic Radial Piston Motors

{0 Comments}

Hydraulic Radial Piston Motors

Radial piston motors produce very high torque at low speed. They are used as wheel motors for large equipment. Pistons operate in radial bores in a stationary cylinder block. The surrounding housing rotates (Fig. 5.18). The rotating housing has two identical cam rings. The pistons each have two cam rollers. An extending piston forces the …

Read More…

Design Considerations for Bent Axis Motors

{0 Comments}

Design Considerations for Bent Axis Motors

The piston shaft (tapered section shown in Fig. 5.15) does not provide the linkage that ensures that the cylinder block rotates with the output shaft. This linkage is provided with another mechanism. Different manufacturers use various mechanisms to develop this synchronizing torque, and this detail is beyond the scope of this text. The key point …

Read More…

Hydraulic Bent Axis Motors

{0 Comments}

Hydraulic Bent Axis Motors

Bent axis motors were developed to improve the operating and stall torque efficiencies of high-speed motors. The design (Fig. 5.15) operates in a manner similar to that of the axial piston design. A series of cylinders are mounted around the center line of the bent axis. The pistons in these cylinders have a spherical end …

Read More…

Geroler Motor (Disc Valve) Performance Characteristics

{0 Comments}

Geroler Motor (Disc Valve) Performance Characteristics

The Char-Lynn 10,000 series motor with 40.6 in3/rev displacement was chosen for an example. (Notice that this displacement is approximately 10 times the displacement of the high-speed motors previously studied.) This motor has a maximum speed of 254 rpm for continuous operation. Maximum pressure is 3000 psi. Efficiencies were calculated for an input flow of …

Read More…

Hydraulic Piston Motor Efficiency

{0 Comments}

Hydraulic Piston Motor Efficiency

The fixed displacement axial piston motor (Sauer-Danfoss Model 90-075 MF), comparable to the variable displacement axial piston pump (Sauer-Danfoss Model 90-075 PV), was chosen. This motor has a maximum speed of 3950 rpm and a rated pressure of 6000 psi. Displacement is 4.57 in3/rev. Efficiencies were calculated for a 36 GPM input flow. Torque efficiency …

Read More…

Hydraulic Vane Motor Efficiency

{0 Comments}

Hydraulic Vane Motor Efficiency

A Vickers Model 25M (65) vane motor was chosen for the comparison. This motor is rated for 3000 rpm at 2500 psi maximum pressure. It has a displacement of 4.19 in3/rev. Efficiencies were calculated for a 35 GPM input flow. As shown in Fig. 5.4, the torque efficiency for this design is higher than for …

Read More…
You might also likeclose