High-Torque PKP Series Stepper Motors

After revising the magnetic design and structure design of the PKP Series, it products much more torque than the conventional motors of the same size. In addition, torque can be increased in the high-speed range by using high current motors.

Reduced Power Consumption and Heat Output

If the running current of a PKP Series stepper motor is decreased and the motor is operated at the same torque as the PK Series standard type, current consumption and heat output can be reduced.

Downsizing

The PKP Series stepper motors provide torque equivalent to a stepper motor of the next larger frame size, contributing to downsizing of equipment.

Utilizing Hybrid Stepper Motor Technology

A hybrid stepper motor is a combination of the variable reluctance and permanent magnet type motors. The rotor of a hybrid stepper motor is axially magnetized like a permanent magnet stepper motor, and the stator is electromagnetically energized like a variable reluctance stepper motor. Both the stator and rotor are multi-toothed.

A hybrid stepper motor has an axially magnetized rotor, meaning one end is magnetized as a north pole, and the other end a south pole. Toothed rotor cups are placed on each end of the magnet, and the cups are offset by half of a tooth pitch.

Increased Resolution (Compared to Standard Type)

The number of rotor teeth has doubled to 100 compared to 50 with the standard type stepper motor. As a result, the basic step angle becomes 0.9°/step which is half that of the standard type stepper motor.

These high resolution stepper motors have half the step angle of standard stepper motors. The high resolution type increases motor resolution from 200 steps/revolution to 400 steps/revolution. Smaller step angles can be achieved by half-step driving or microstep driving. Other than having twice as many rotor teeth as standard stepper motors, all other structures are exactly the same as standard stepper motors.

Improved Stopping Accuracy (Compared to Standard Type)

The stopping accuracy improves as the torque increases while minimizing the negative effect of the frictional load.

Broader Permissible Speed Range than Conventional Products

The New SH geared lineup now offers up to 60% more speed than current conventional models and is effective for increasing torque, achieving higher resolution and reducing vibration.

Backlash Accuracy Guaranteed

Backlash, which was a reference value in conventional models, is now a specification value.

Unit = arc min (degrees)

Increased Permissible Torque and Load

The CS geared type has increased torque and a large shaft for greater loads without the requirement for a larger gear frame size.

As shown in the structural drawing, by losing gears, the output shaft can be placed at the central axis.

Encoder Type Stepper Motors

A rotary encoder is an electro-mechanical device that converts the angular position of a shaft to an analog or digital code. There are two main types: absolute and incremental. Oriental Motor offers incremental types (Line Driver or Voltage (TTL equivalent)) as a standard product for our stepper motors. For an absolute encoder solution, use the AZ Series. For other standard product encoder offerings and motors that correct themselves, contact technical support  for assistance.

An incremental encoder provides the incremental change in position of the encoder to the counting electronics. Stepper motors with incremental encoders make it possible to monitor the present position and detect for errors. Position monitoring can be used to detect the position of the motor. For instance, to confirm normal operations, compare commanded position to the actual position.

3-Channel Encoders

Use the Index signal for the return-to-home operation. By using the Index signal, the return-to-home point will be detected with higher accuracy than single use of the return-to-home sensor. The index channel is an optional output channel which provides one pulse per revolution.

Line Driver Output Type

The Line Driver output offers excellent noise resistance because of the differential output and is capable of longer wiring distance compared to the voltage output.

Electromagnetic Brake Option

These products have built-in power-off activated electromagnetic brakes. When power is accidentally cut off due to a blackout or other unexpected events, the electromagnetic brake holds the load in position to prevent it from dropping or moving. Also, when the motor is at standstill, it is held by the electromagnetic brake. It is possible to suppress the heat generated from the motor by turning off the motor current.

For product names, product name-identifying characters are used.

Compact and Flat Connector

The PKP Series 1.65 in. [42 mm] and 2.22 in. [56.4 mm] frame size are available with a compact and flat connector, which shortens the length of the connectors overhang. In addition, the degree of freedom for the cable outlet direction has been increased because the outlet direction points upward.

Standard Motor Connector

Stepper motor lead wire connector can be inserted^*1 and the locking mechanism prevents accidental removal^*2

Wiring Configuration Options

• Unipolar - 6 lead wires

^*1 Except for stepper motor frame size of 20 mm (0.79 in.)
^*2 Only motor frame sizes of 35 mm (1.38 in.) 42 mm (1.65 in.), 56.4 mm (2.22 in.) and 60 mm (2.36 in.)

Comparison of the Flat Connector Type and the Connector Type For 2-Phase Stepper Motors

Type		Flat Connector Type	Connector Type
Features		Using a compact flat connector shortens the length of the connector’s overhang High permissible radial load/permissible axial load High torque (excluding some types)	Standard performance
Permissible Radial Load (Max. value)	42 mm	85 N (63% Increase)	52 N
	56.4 mm	270 N (68% Increase)	160 N
Permissible Axial Load	42 mm	15 N (50% Increase)	10 N
	56.4 mm	30 N (50% Increase)	20 N
Speed - Torque Characteristics (Reference values)		Example of comparison of Torque characteristics with the same size motor (42 mm bipolar)