JP2003165694A - Electronic limit switch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic limit switch capable of decelerating and stopping in a stop position directly set from a panel without movement of a hook block. <P>SOLUTION: This switch is characterized in that the stop position of the hook block 30 and a limit switch position are directly inputted and set from a panel of an inverter by detecting a rotational frequency of a lifting motor. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an electronic limit switch. More specifically, the present invention relates to a technique of detecting the number of revolutions of a hoisting motor for an inverter hoist and stopping the hook block (cargo handling) at a distance (position) set by panel input.

[0002]

2. Description of the Related Art Conventionally, when setting a stop position in an inverter hoist, a hook block is moved up and down to visually stop at a stop position, and the rotation pulse of a hoisting motor at that time is integrated. This is done by converting it to a moving distance and storing it. Alternatively, the detection position is set using a sequencer or the like.

[0003]

The above-mentioned prior art has the following problems. 1. The travel distance is not displayed on the inverter panel. 2. Direct input from the inverter panel cannot be set. In the prior art, only the method of arbitrarily setting the stop position by visual observation is used. The reason is that the inverter alone has a small number of pulses of the rotation sensor to simplify the operability and the capacity of the CPU and ROM is insufficient. it is conceivable that.

[0004]

An electronic limit switch according to claim 1 of the present invention which solves the above-mentioned problems, detects the rotation speed of a hoisting motor to determine the stop position and limit switch position of a hook block. The feature is that it is set by inputting directly from the inverter panel. According to a second aspect of the present invention to solve the above-mentioned problems, the electronic limit switch according to the first aspect is characterized in that the present position of the hook block is displayed on the panel of the inverter. The electronic limit switch according to claim 3 of the present invention for solving the above-mentioned problems is characterized in that, in claim 1 or 2, the stop position and the limit switch position of the hook block are displayed on the panel of the inverter.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described in detail with reference to the embodiments shown in the drawings. FIG. 1 shows an inverter hoist according to the first embodiment of the present invention. As shown in FIG. 1, when the drum 20 is driven and rotated by the hoisting electric motor 10, the hook block 30 is passed through the wire.
Can be wound up or down, and the rotation speed of the hoisting motor 10 is detected by the rotary encoder 40. By adjusting the inverter frequency for the hoisting motor 10, the speed can be controlled to be constant regardless of the load or the power supply, or the speed can be controlled to be the set speed.

A brake 60 is provided on the drum 20 via a speed reducer 50 so as to prevent a shock and enable a smooth start / stop operation. Furthermore, control box 7
0 is provided with a push button 80 so that various operations can be performed, and a panel (not shown) is provided. In addition, 90 is a lever. In this embodiment, the stop position and the limit switch position of the hook block 30 are directly set by the panel of the control box 70 without moving the hook block 30 up and down.

That is, as shown in FIG. 2, the hook block 30 starts decelerating when it is wound up beyond the hoisting deceleration start position ULS1 and stops at the upper limit stop position ULS0. When it is wound down beyond the start position DLS1, deceleration starts and the lower limit stop position DLS0
It is supposed to stop at. Upper limit stop position ULS
0, hoisting deceleration start position ULS1, hoisting deceleration start position DL
Both S1 and the lower limit stop position DLS0 are set as the hook block movement distance FSX. The calculation formula of the hook block moving distance FSX is as follows. The following formula is obtained based on the moving distance per one revolution of the hoisting motor. FSX = (π × D / ns) × (N _R / i)

However, FSX: Hook block movement distance [mm] π: Circumferential ratio D: Effective drum diameter [mm] i: Reduction ratio ns: Coefficient N _R due to the suspension structure: Rotational speed of the hoisting motor (rotation pulse) It is necessary to set LS1 as the origin as an initial setting.

The outline of the procedure for setting the stop position and the limit switch position of the hook block 30 in the above-mentioned inverter hoist is as follows. 1) Set calculation parameters. 1.1) Set the effective drum diameter D on the panel. The set numerical value of 0.0 to 99999 [mm] is displayed on the panel. 1.2) Set the reduction ratio i on the panel. The set numerical value of 0.00 to 999.99 is displayed on the panel. 1.3) Set the coefficient ns due to the suspension structure on the panel. The set numerical value of 0 to 99 is displayed on the panel.

2) Enter the setting method on the panel. The setting method refers to any of the origin position LS1, the upper limit stop position ULS0, the hoisting deceleration start position ULS1, the lowering deceleration start position DLS1, and the lower limit stop position DLS0 as described below.

3) Electronic limit switch position setting 3.1) Setting of origin position LS1 Move to setting panel. The current position (FSX) is displayed on the panel as needed. Use the push button (manual operation) to wind up to the lever 90 at a slow speed and set the origin. As FSX → 0, the panel also displays 0.

3.2) Setting method of upper limit stop position ULS0 (direct panel input setting) Move to the setting panel. Input the upper limit stop position ULS0 directly from the panel. The input numerical value of 0 to 99.999 [mm] is displayed on the panel. Write the ULS0 data to the EEPROM.

3.3) Method of setting hoisting deceleration start position ULS1 (panel direct input setting) Move to the setting panel. The hoisting deceleration start position ULS1 is directly input from the panel. The input numerical value of 0 to 99.999 [mm] is displayed on the panel. Write the ULS1 data to the EEPROM.

3.4) Method for setting the lowering deceleration start position DLS1 (panel direct input setting) Move to the setting panel. The lowering deceleration start position DLS1 is directly input from the panel. The input numerical value of 0 to 99.999 [mm] is displayed on the panel. Write DLS1 data to EEPROM.

3.5) Setting method of lower limit stop position DLS0 (direct panel input setting) Move to the setting panel. Enter the lower limit stop position DLS0 directly from the panel. The input numerical value of 0 to 99.999 [mm] is displayed on the panel. Write the DLS0 data to the EEPROM.

4) Select the electronic limit switch function selectable. However, if all of the following conditions are not satisfied, an error is displayed and the setting value of item 3) is input again. ULS0 <ULS1 <DLS1 <DLS0 ULS1-ULS0 ≧ 0.150 [m] DLS1-ULS1 ≧ 0.150 [m] DLS0-DLS1 ≧ 0.150 [m]

The work procedure according to the above 1) to 4) is executed according to the flowchart shown in FIG. First, it is determined whether the inverter power supply is ON (step S1),
When the inverter power is off, the following step S
2 to step S9 are skipped. Next, when the inverter power supply is ON, it is determined whether the electronic limit switch function is in use (step S2). When the electronic limit switch function is in use, the subsequent step S3 is performed.
-Skip step S9.

Subsequently, when the electronic limit switch function is not used, it is determined whether or not the electronic limit switch position setting is performed (step S3). When the electronic limit switch position setting is not performed, the subsequent step S4 is performed. -Skip step S9. Furthermore, when setting the electronic limit switch position, it is determined whether or not the origin setting is completed (step S4), and when the origin setting is completed, step S5 is skipped.
When the origin setting is not completed, the origin position LS1 is set by the above procedure (step S5).

Then, it is judged whether or not the inverter is in operation (step S6), and when the inverter is in operation, steps S7 to S9 are skipped. During the inverter operation, the effective drum diameter D, the reduction ratio i, the coefficient ns due to the lifting structure, the upper limit stop position ULS0, the hoisting deceleration start position ULS1, the lowering deceleration start position DLS1, and the lower limit stop position DLS0 are paneled by the above procedure. Directly enter, EEPRO
Write to M (step S7). In addition, it is determined whether the electronic limit switch function is used (step S
8) If not used, step S9 is skipped.

When using the electronic limit switch function, it is determined by the following equation whether or not there is a setting error (step S9). If there is a setting error, step S2
~ Repeat S8. ULS0 <ULS1 <DLS1 <DLS0 ULS1-ULS0 ≧ 0.150 [m] DLS1-ULS1 ≧ 0.150 [m] DLS0-DLS1 ≧ 0.150 [m]

According to the above-mentioned flowchart, if the stop positions ULS0, DLS0 and the deceleration start positions ULS1, DLS1 which are the limit switch positions are directly inputted from the panel of the inverter, the hook block 30 is decelerated from the deceleration start positions ULS1, DLS1. Let stop position UL
It is possible to stop at S0 and DLS0. Here, the stop positions ULS0, DLS0 and the deceleration start position ULS1,
The DLS1 is stored in the memory even when the inverter power is off.

[0022]

As described above in detail with reference to the embodiments, according to the present invention, the number of revolutions of the hoisting motor for the inverter hoist is detected and set directly from the panel without moving the hook block. It can be decelerated to the stopped position and stopped. There is also an advantage that the current position of the hook block can be displayed on the panel as the moving distance of the hook block at any time.

[Brief description of drawings]

FIG. 1 is a schematic diagram of an inverter hoist according to an embodiment of the present invention.

FIG. 2 is an explanatory view showing a stop position and a limit switch position of the hook block according to the embodiment of the present invention.

FIG. 3 is a flow chart for realizing an electronic limit switch as an embodiment of the present invention.

[Explanation of symbols]

10 hoisting motor 20 drums 30 hook blocks 40 rotary encoder 50 reducer 60 brakes 70 control box 80 push button

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Takeshi Kushida             2-5-15 Osaki, Shinagawa-ku, Tokyo Meidenho             Within Ist System Co., Ltd.

Claims (3)

[Claims] 1. An electronic limit switch, characterized in that the stop position of a hook block and the limit switch position are directly input and set from an inverter panel by detecting the number of revolutions of a hoisting motor. 2. The electronic limit switch according to claim 1, wherein the current position of the hook block is displayed on the panel of the inverter. 3. The electronic limit switch according to claim 1, wherein the stop position and the limit switch position of the hook block are displayed on the panel of the inverter.