JPS5854080B2 - hoisting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a hoisting device, particularly an electric hoist with a slow speed.

When operating at high speed in a conventional two-prong speed electric hoist, the electromagnetic clutch and the electromagnetic brake are deenergized at the same time when the motor is stopped. The clutch also acts as a type of brake, which has the disadvantage of shortening its lifespan.

This invention was made to solve these drawbacks, and includes a reduction mechanism that drives the winding drum, a high-speed hoisting motor connected to the input side of this reduction mechanism, and a brake connected to the high-speed hoisting motor. An electromagnetic brake that opens when the coil is energized, an electromagnetic clutch whose output side is connected to the input side of the reduction mechanism described above, and an electromagnetic clutch that opens when the clutch coil is energized, and a low-speed brake that is connected to the input side of this electromagnetic clutch. A series circuit of the hoisting motor, the brake coil and the clutch coil, an energization switch that energizes the series circuit when either the high-speed hoisting motor or the low-speed hoisting motor is in operation, and a energization switch connected in parallel to the clutch coil. By providing a short-circuit switch that short-circuits the clutch coil during operation of the low-speed hoisting motor, and a diode that is connected in parallel to the clutch coil and causes a residual current to flow through the clutch coil when the energization switch is released, the life of the clutch can be improved. The purpose of this invention is to provide a hoisting device that can improve the

The figure will be explained below. In Figure 1, HM is a high-speed hoisting motor, LM is a low-speed hoisting motor, BR is an excited open electromagnetic brake connected to one side of the rotating shaft of the high-speed hoisting motor HM, and G1 is the rotation of the high-speed hoisting motor. A first speed reduction mechanism connected to the other side of the shaft, D a winding drum connected to the output shaft of this first speed reduction mechanism, and G2 a second speed reduction mechanism connected to the rotating shaft of the low speed hoisting motor LM. An electromagnetic clutch CL of an excitation release type is inserted between this second speed reduction mechanism and the first speed reduction mechanism G1.

Next, the operation shown in FIG. 1 will be explained.

During high-speed operation, when the electromagnetic brake BR and electromagnetic clutch CL are energized and released, and the high-speed hoisting motor HM is started, the winding drum is driven at high speed via the first reduction mechanism G1.

Furthermore, during low-speed operation, when only the electromagnetic brake BR is opened and the low-speed hoisting motor LM is started, the winding barrel is driven at low speed via the second reduction mechanism G1 - electromagnetic clutch CL - second reduction mechanism G2. .

Next, the main circuit shown in FIG. 2 will be explained.

In Figure 2, HU-1 and HD-1 are high-speed hoisting and hoisting contactors, LU, L, and D-1 are low-speed hoisting and hoisting contactors, and LS2 is an upper limit switch (second stage). ), Re is a rectifier inserted into the main circuit of the high-speed hoisting motor HM,
CLC is a clutch coil for controlling the electromagnetic clutch CL, BRC is a brake coil for controlling the electromagnetic brake BR, and BrS is a half-off switch,
These clutch coil CLC, brake coil BRC
, quick-off switch BrS are connected in series to the rectifier Re.

L is a short circuit switch connected in parallel with the clutch coil CLC, and FD is a delayed return element, such as a flywheel diode, connected in parallel with the clutch coil CLC.

Next, the operation of the circuit shown in FIG. 2 will be explained.

During high-speed operation, when the contactor HU-1 or HD-1 is turned on, the current flows through the rectifier Re-clutch coil CLC-
It flows through the path of the bunkie coils BR, C, the early cut-off switch Br5, and the high-speed hoisting motor HM.

Therefore, when the clutch CL and the brake BR are released, the winding barrel shown in FIG. 1 is rotated at high speed.

When stopping operation, contactor HU-1 or HD-1
By opening the clutch coil, the high-speed motor circuit is opened, and the electromagnetic brake coil BRC is also deenergized immediately, so the braking operation starts immediately.However, since the diode FD is connected to the clutch coil CLC, the residual current flows between clutch coil CLC and diode FD, so clutch CL is maintained in an open state for a while.

Next, low speed operation will be explained.

When the contactor LTJ-1 or LD-1 is turned on, the low-speed hoisting motor LM is started and the current is transferred to the contactor LU.
-1 or LD-1, passes through the rectifier Re, and flows through the path of the switch brake coil BRC, the quick-off switch Br5, the rectifier Re, and the low-speed hoisting motor LM.

In this way, in the case of low-speed operation, the short-circuit switch L is turned on and the electromagnetic clutch coil CLC- is short-circuited, so the electromagnetic clutch coil CLC is not excited and the electromagnetic clutch CL (Fig. 1) maintains the closed state. do.

Therefore, only the electromagnetic brake BR is released, and the winding drum shown in FIG. 1 is driven at low speed by the low speed hoisting motor LM.

Next, the operating circuit diagram shown in FIG. 3 will be explained.

In Figure 3, PB-HU and PB-HD are high-speed hoisting,
Lowering push button switch, PB-LU, PB-LD is low speed hoisting, lowering push button switch, HUC.

HDC is a control coil for high-speed hoisting and hoisting magnetic contactors, and includes contactors HU-1, HD-1 in the main circuit and auxiliary contactors HU-1a HD-1a HU-1b, H in the operation circuit.
Controls D-1b, HU-1c, and HD-1c.

The LSI is an upper limit switch (first stage).

LUC and LDC are the control coils of the low-speed upper and lower magnetic contactors, which control the main circuit contactor LU-1゜LD-1 and the operation circuit auxiliary contactors LU-1a, LD-1a, LU.
-1b, LD-1b, LU 1c, LD-1c, LU
-1d and LD-1d.

Br5C is a control coil for the quick-off switch BrS (Fig. 2).

Next, the operation shown in FIG. 3 will be explained.

When the high-speed push button switch PB-HU or HD is pressed, the control coil HUC or HDC is energized, so the contactor HU-1 or HD-1 shown in Fig. 2 is turned on, and high-speed operation is performed as described above. Ru.

Also, when the low-speed pushbutton switch PB-LU or PB-LD is pressed, the control coil LUC or LDC is energized, so the contactor LU-1 or LD-1 shown in Fig. 1 is turned on and the low-speed motor LM is rotated. together with the control 'coil LC
Since Br5C is excited, the short circuit switch L and quick cut switch BrS in Fig. 2 are closed, and the brake coils BR,
Only C is excited and brake BR is released.

As described above, this invention includes a reduction mechanism that drives the winding drum, a high-speed hoisting motor connected to the input side of this reduction mechanism, and a brake coil connected to the high-speed hoisting motor that is released when energized. an electromagnetic brake, an electromagnetic clutch whose output side is connected to the input side of the reduction mechanism, and which opens when the clutch coil is energized, a low-speed hoisting motor connected to the input side of the electromagnetic clutch, the brake coil and the above A series circuit with the clutch coil, an energizing switch that energizes the series circuit when either the high-speed hoisting motor or the low-speed hoisting motor is operating, and an energization switch that is connected in parallel to the clutch coil and energizing the above-mentioned series circuit when the low-speed hoisting motor is operating. It is equipped with a short-circuit switch that short-circuits the clutch coil, and a diode that is connected in parallel to the clutch coil and causes a residual current to flow through the clutch coil when the energization switch is released. It is connected just before that, which has the advantage of long life.

[Brief explanation of the drawing]

The figures relate to an embodiment of the present invention, with FIG. 1 being a schematic diagram of the configuration, FIG. 2 being a main circuit diagram, and FIG. 3 being an operating circuit diagram. Note that the same reference numerals in the figures indicate the same parts. HM...High-speed hoisting motor, LM...Low-speed hoisting motor, D...Hoisting drum, BR,...
・Electromagnetic brake, CL・・・・Electromagnetic clutch, FD
...Delayed return element.

Claims (1)

[Claims] 1. A reduction mechanism that drives the winding drum, a high-speed hoisting motor connected to the input side of this reduction mechanism, an electromagnetic brake that is connected to this high-speed hoisting motor and is released when the brake coil is energized, and the above-mentioned reduction mechanism. The output side is connected to the input side of
An electromagnetic clutch that opens when the clutch coil is energized, a low-speed hoisting motor connected to the input side of the electromagnetic clutch, a series circuit between the brake coil and the clutch coil, and the high-speed hoisting motor and the low-speed hoisting motor. an energizing switch that energizes the series circuit when either one of the upper motors is operating; a shorting switch that is connected in parallel to the clutch coil and shorts the clutch coil when the low-speed hoisting motor is operating; and a shorting switch that is connected in parallel to the clutch coil. A hoisting device comprising a diode that causes a residual current to flow through the clutch coil when the energization switch is opened.