Selecting an Electric Linear Slide/Electric Cylinder: Tentative Selection of Electric Actuators

Selection Method

(1) Confirming the Required Specifications

Confirm the required specifications for the equipment.

(1) Confirming the Required Specifications
Load Mass
m = 15 [kg]
Positioning Distance
L = 500 [mm]
Positioning Time
T = Within 2 seconds
Drive Direction
Vertical

(2) Tentative Selection of Electric Actuators

The following electric actuator is tentatively selected based on the required specifications.

Product name
EASM6
Lead
6 mm
Power Supply Input
Single-Phase 200 VAC

(3) Confirming the Positioning Time

Check whether the actuator can perform the necessary positioning within the specified time. This can be done by obtaining a rough positioning time from the graph or by obtaining a fairly accurate positioning time by calculation. Each of the confirmation procedures is explained below.
The actual operating time is subject to a small margin of error, so use the calculation only as a reference.

Using the Tool for Calculating the Shortest Positioning Time

For applicable products of Oriental Motor’s electric linear slides and electric cylinders, the approximate positioning time can be calculated by "model" and "operation conditions."

Click here for a tool to calculate the shortest positioning time

Using the Tool for Calculating the Shortest Positioning Time

Obtaining From a Graph

Use the graph to confirm the positioning time necessary for a positioning distance of 500 mm.

Positioning Time: 1.77 s

The requested positioning time of 2 seconds or less is satisfied, so it can be used.

If the positioning time requirement is satisfied, check the operating speed and acceleration.

Operating Speed: 320 mm/s
Acceleration  : 1.5 m/s2(0.15 G)

If the positioning time requirement is not satisfied, select a different model.
Obtaining From a Graph

Using Formula Calculations

Confirm operation conditions

Check the following conditions:
Positioning distance, starting speed, acceleration, and operating speed

From the operation conditions above, confirm whether the drive pattern is a triangular drive or trapezoidal drive

Calculate the maximum speed of triangular drive from the positioning distance, starting speed, acceleration and operating speed. If the calculated maximum speed is equal to or below the operating speed, the operation is considered a triangular drive. If the calculated maximum speed exceeds the operating speed, the operation is considered a trapezoidal drive.

\(\begin{align} V_{Rmax} &= \sqrt{ \frac{2 \cdot a_1 \cdot a_2 \cdot L}{a_1 + a_2} \cdot 10^3 + V_{S^2}} \\[5pt] V_{Rmax} & \leqq V_R \rightarrow \text{Triangular Drive} \\[5pt] V_{Rmax} & \gt V_R \rightarrow \text{Trapezoidal Drive}\end{align}\)

Calculate the positioning time

[In the case of trapezoidal drive]

\(\begin{align}T &= T_1 + T_2 + T_3 \\[5pt] & = \frac{V_R - V_S}{a_1 \times 10^3} + \frac{V_R - V_S}{a_2 \times 10^3} + \frac{L}{V_R} - \frac{\left(a_1 + a_2 \right) \times \left(V_{R^2} - V_{S^2} \right)}{2 \times a_1 \times a_2 \times V_R \times 10^3} \end{align}\)

[In the case of triangular drive]

\(\begin{align}T &= T_1 + T_2 \\[5pt] & = \frac{V_{Rmax} - V_S}{a_1 \times 10^3} + \frac{V_{Rmax} - V_S}{a_2 \times 10^3} \end{align}\)
③ Calculate the positioning time
VRmax
Maximum Speed Calculated for Triangular Drive [mm/s]
VR
Operating Speed [mm/s]
Vs
Starting Speed [mm/s]
L
Positioning Distance [mm]
a1
Acceleration [m/s²]
a2
Deceleration [m/s²]
T
Positioning Time [s]
T1
Acceleration Time [s]
T2
Deceleration Time [s]
T3
Constant Speed Time [s]

The actual operating time is subject to a small margin of error, so use the calculation only as a reference.

Other conversion formulas are explained below.
The pulse speed and operating speed can be converted using the formula below. Keep the operating speed below the specified maximum speed.

\(\begin{align}\text{Pulse Speed [Hz]} =\frac{\text{Operating Speed [mm/s]}}{ \text{Minimum Travel Amount [mm]}}\end{align}\)

The number of operating pulses and travel amount can be converted using the formula below.

\(\begin{align}\text{Number of Operating Pulses [Pulse]} =\frac{\text{Travel Amount [mm]}}{ \text{Minimum Travel Amount [mm]}}\end{align}\)

The acceleration/deceleration rates and acceleration can be converted using the formula below.

\(\begin{align}\text{Acceleration/Deceleration Rates [ms/kHz]} =\frac{\text{Minimum Travel Amount [mm] × }10^3}{ \text{Acceleration [}m/s^2\text{]}}\end{align}\)

The input methods for speed, travel amount, and acceleration vary depending on the host control device. Please calculate according to your usage.