JPH05319788A - Double speed type variable speed electric hoist - Google Patents

Abstract

PURPOSE:To set a speed optimum to application to an arbitrary value by using a rotation type variable resistor for a variable resistor on the low speed side and deciding the synthetic resistance value of a circuit to an arbitrary value. CONSTITUTION:A speed is varied through the change of the resistance value of a variable resistor and both low and high speeds are variable in a given range. On the low speed side, especially, a rotation type variable resistor 28 is used for a variable resistor. Resistance between terminals 2-3 wherein a resistance value is decreased through clockwise rotation and resistance between terminals 2-1 wherein a resistance value is decreased through counterclockwise rotation are properly used for a 50Hz use or 60Hz use by means of a change- over switch 29 or the change of connection. Further, to form a rotation type, a fixed resistor 30 is connected in series to resistance between terminals for a 50Hz use of the resistor 28, fixed resistance 31 is connected in parallel to resistance between terminals for a 60Hz use, and further and a fixed resistor 32 is connected in series to a parallel circuit to form a circuit. Respective synthetic resistance values are decided so that the same electric motor voltage generated at both 50Hz and 60Hz.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric hoist, and more particularly to a double speed variable speed type for controlling hoisting / lowering speed and controlling hoisting / lowering speed in an electric hoisting machine. Electric hoist

[0002]

2. Description of the Related Art Conventionally, in an electric chain block or the like, in general, a push button switch hung from a hoisting machine main body through a cable, and in the case of a hoisting operation, by pushing an upper command button of the push button switch, a winding operation is performed again. In the case of the down operation, by operating the lower command button, the electromagnetic contactor is controlled to change the rotation direction of the electric motor.

Further, as a double speed type electric chain block for obtaining two speeds of low speed and high speed, the electric motor is a so-called double winding type having two kinds of windings having different numbers of poles, and a two-stage motion ( By pressing the first and second steps of the push button switch, the low-speed / high-speed switching electromagnetic contactor is operated to switch the rotation speed of the electric motor to change the speed. A number conversion electric motor is known.

Further, as a variable speed type electric chain block capable of changing from low speed to high speed, a push button switch section is provided with a speed designation operation section consisting of a variable resistor,
By this operation, a signal is sent to the voltage control section built into the hoisting machine body, and the applied voltage of the electric motor is changed,
It is known that the number of revolutions is variably controlled so that an arbitrary speed can be set.

Here, the above-mentioned three types of conventional techniques will be described with reference to FIGS. 8 to 10. First, in FIG. 8, 1 is a hoisting / lowering electric motor, and 2 is an electric equipment housing in which various electric equipment is housed. 3 is an upper hook for suspending an electric chain block on a ceiling structure, 4 is a cable, 5 is a chain, 6 is a lower hook for suspending a load, 7 is a hook for engaging the chain, 8 is a cable 4 The operation part attached to the tip is shown, and by operating the operation part 8 at hand, the lower hook 6
Lift and lower the luggage 9 hooked on.

Next, referring to FIG. 9, reference numeral 10 is a winding / lowering electric motor having two types of windings having different numbers of poles, for example, 8 poles and 2 poles, and each of the lead wires 11 and 1.
2 is provided via a cable. 13 is an electromagnetic contactor that changes the winding / winding direction, 14 is an electromagnetic contactor for selectively using the two types of windings, and 15 is the above 2
An operation unit for operating the two electromagnetic contactors 13 and 14, and
By using a push button switch of a stepped motion (two-step pushing) type, first, by a pushing operation of the first step of the upper command button, the winding coil of the electromagnetic contactor 13 is energized to form a winding circuit, and at the same time, the electromagnetic contactor 14 Is non-energized and inoperative, the 8-pole winding of the electric motor 10 is energized, and the electric motor rotates at a low speed for 8-pole.

Next, by further pushing and energizing the electromagnetic contactor 14 for the first time by the operation of the second step, the energization of the 8-pole winding is cut off, and at the same time, the 2-pole winding of the electric motor 10 is energized. For 2 poles, two kinds of speeds, low speed and high speed, are selected by rotating at 4 times as high speed as for 8 poles, and the same applies to the case of unwinding operation.

Further, referring to FIG. 10, reference numeral 1 is a hoisting / lowering electric motor, 16 is an operating portion, and a push button switch 17 for giving a hoisting command and a hoisting command,
It has a variable resistor built-in, and has a speed designation operation section 18 that can be variably operated by operating a knob from the outside.

Reference numeral 19 denotes a control unit for changing a voltage applied to the electric motor by a hoisting / lowering command according to signals from the push button switch 17 and the speed designating operation unit 18 and phase control of the thyristor. By operating the part 18 to variably specify the variable resistor,
The control unit 17 changes the voltage applied to the electric motor 1 to change the number of revolutions and selects an arbitrary speed.

[0010]

Even if a general electric chain block of the prior art is used most often at present, there is no particular problem. However, if the load is on the ground or floor / At the moment of leaving the platform, etc., it is usually called when leaving the ground, but if you wind up and drive at once, the luggage will shake and it will be in a dangerous state, so the purpose is to avoid this danger and damage to the equipment due to the impact when leaving the ground. It is customary that the jogging operation is performed by several continuous operations in order to mitigate this shock, on the contrary,
The same applies when landing luggage. This results in a decrease in work efficiency, a large number of starts and stops, and an accelerated wear of each part including the electrical contacts of the operating part.In such a case, it is desirable to reduce the speed. The speed after separation often needs to be high in order to improve work efficiency, and therefore it is impossible to satisfy both.

In addition, transportation of dangerous substances such as chemicals and explosives, water, etc., precision assembly of parts, die matching work such as press dies,
Depending on the purpose of the work, such as the work of immersing the parts in the plating layer, the above-mentioned inching operation is not sufficient, and it is necessary to basically reduce the speed.

Therefore, according to the double speed type electric chain block, at the time of leaving the ground or landing, the low speed operation is performed to prevent the swinging of the load, the impact is alleviated, and the precision assembling work, the mold matching work and the like position are performed. Alignment is performed effectively, and work efficiency is improved by handling at high speed except when leaving the ground or landing.However, the speed of both the low speed side and the high speed side is specified based on general versatility. Since it is fixed at a constant speed, it does not hinder simple loading and unloading work, but special applications, such as dangerous goods and water, further dislike swinging goods, so it is suitable for that work. It is necessary to keep it at a high speed.

Also, for large heavy objects and the like, it is dangerous at high speed, or the moving height (distance) is low, and low speed is required when high speed is not required.

On the contrary, it is a small and lightweight material and has a high moving height.
When the (distance) is high, the work efficiency is low at low speed, so higher speed is required.

In view of these, the speed setting cannot be determined unconditionally, and is not satisfactory in such a case.

Further, the variable speed electric chain block is
It is possible to select and set the best arbitrary speed according to the type and application of luggage within the range from a predetermined low speed to high speed, but at the above-mentioned landing and landing, it is low speed operation, other than that It is not satisfactory when high speed operation is performed during transportation and a combination of low speed and high speed is required.

The variable speed system is a phase control system using a thyristor and has power source frequencies of 50 Hz and 60 H.
Due to the difference in the waveform from the time of z, the output voltage (voltage applied to the motor) becomes smaller at 60 Hz even if the variable resistors are set to be the same and the same phase control is performed. It increases as the voltage is reduced.

That is, it means that the same hoisting machine has a low speed when used in the 60 Hz area, compared to the 50 Hz area. For example, if the lowest speed that can be operated in 50 Hz is set, the operation will be performed in the 60 Hz area. It becomes impossible (insufficient voltage), and conversely, even if the minimum speed that can be operated at 60 Hz is set, the result will be too fast at 50 Hz.
It was strongly desired to overcome this difference and set the same speed in both the 50 Hz area and the 60 Hz area.

[0019]

The present invention is exactly applicable to this, and the means are as follows.

The speed can be changed by changing the resistance value of the variable resistor, controlling the voltage applied to the electric motor by the phase control of the thyristor, and changing the number of revolutions thereof to change the hoisting / lowering speed. There are two types of speed, low speed and high speed, which can be selectively used by operating a push button switch, and both low speed and high speed can be varied within a predetermined range.

On the high speed side, the variable resistor provided in the push button switch section is operated to change the resistance value to control the voltage of the electric motor.

On the low speed side, in particular, even if the same phase control is performed, the voltage applied to the motor is different at power source frequencies of 50 Hz and 60 Hz. Therefore, a rotary variable resistor is used as the variable resistor to rotate the variable resistor clockwise. Between the terminals where the resistance value decreases and between the terminals where the resistance value decreases by left rotation for 50Hz for 60Hz by a changeover switch or connection change, etc.
It is configured to be used properly for z.

A fixed resistor is connected in series to the 50 Hz terminal resistance of the rotary variable resistor, and a fixed resistor is connected in parallel to the 60 Hz terminal resistance, and the fixed resistor is connected to the parallel circuit. 50H as a circuit configuration for connecting in series
Each combined resistance value is determined so that the same motor applied voltage can be obtained at z and 60 Hz, and one rotary variable resistor is used.
The voltage applied to the electric motor is controlled so that the same speed can be obtained by selectively using 0 Hz.

Here, the rotary variable resistor on the low speed side and the changeover switch are initially operated according to the power supply frequency and special application, and do not need to be operated at all times. The push-button switch, which is provided inside the machine body and is in the hands of the customer, has only a minimum number of parts.

[0025]

According to the present invention shown in the above-mentioned means, first, the speed is set to two types, low speed and high speed, and the push button switch is operated so that it can be used properly such as low speed start-high speed operation-low speed stop. You can

Further, at both low speed and high speed, each variable resistor is operated to change the resistance value to select and set an arbitrary speed according to the application within a predetermined range, thereby achieving the most efficient operation. The speed can be determined.

Further, a rotary variable resistor is used as the variable resistor, and a terminal whose resistance value decreases by clockwise rotation and a terminal whose resistance value decreases by counterclockwise rotation have power supply frequencies of 50 Hz and 60H.
By properly using z and connecting a fixed resistor in series or in parallel, the maximum and minimum values of the respective combined resistance values are arbitrarily determined according to the required circuit constants,
5 depending on the changeover switch, connection change, etc.
Since the same voltage applied to the electric motor can be obtained at 0 Hz and 60 Hz, the same speed can be set. Therefore, the same speed can be set regardless of the power source frequency regardless of where it is used nationwide.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to an embodiment in which it is applied to an electric chain block, based on one embodiment shown in FIGS. 1 to 7. FIG. Fig. 3 is an external view of a chain block incorporating the electric circuit shown in Fig. 3, Fig. 3 is a structural explanatory diagram of the rotary variable resistor and changeover switch 29 shown in Fig. 1, and Fig. 4 is a power source frequency of 50Hz and 60H.
FIG. 5 is a voltage waveform diagram of z, FIG. 5 is a relationship curve diagram of speed and combined resistance value, and FIG. 6 is an operation explanatory diagram of the electric chain block shown in FIG.

In FIG. 2, reference numeral 1 is a hoisting / lowering electric motor, 2 is an electric equipment housing portion for housing various electric equipment such as a control unit for the voltage applied to the electric motor, and 3 is an electric chain block suspended from a ceiling structure. An upper hook, 20 is an operating unit composed of a push button switch and a variable resistor, 4 is a cable for transmitting a signal of the operating unit to electric components inside the hoisting machine main body, 5 is a chain, and 6 is a lower part for hanging a load. Shows the hook, operation unit 2
With the hand operation of 0, the operation signal is passed through the cable 4 and the operation command of hoisting / lowering and the hoisting / lowering
A command to control the voltage applied to the hoisting motor 1 is transmitted to the electrical component storage unit 2, and the control unit 19 controls the direction of rotation of the hoisting and unwinding motor 1 and the number of revolutions thereof, thereby making -The downward movement direction and its speed are changed to raise and lower the load hooked on the lower hook 6.

Next, a circuit configuration and an operating method will be described with reference to FIGS.

First, the case of the low-speed winding operation will be described with reference to FIGS. 1 and 2. The power supply frequency is 50 Hz or 60 Hz, and the push button switch is a two-stage push type switch in order to improve usability.
The one that gives a low speed command at the first step and a high speed command at the second step is adopted.
a is closed, the winding relay coil 25 of the electric component built into the main body of the hoisting machine is excited, and thereby the contact 25a of the winding relay of the control circuit of the electric motor 1 is closed, the energization is started, and the electric motor 1 rotates. ..

At this time, the voltage applied to the electric motor 1 is determined by the voltage control circuit section 26, and its magnitude is determined by the combined resistance of the low speed variable operating section 27.

The details of the low speed variable operating section 27 will now be described.

First, when the power supply frequency is 50 Hz and 60 Hz, different waveforms are obtained as shown in FIG. 4, and when the same phase control is performed with the same resistance value and the output starts at the same time t, the output voltage is The effective value (voltage applied to the motor) becomes smaller at 60 Hz as shown by the diagonal lines, and as shown in the example of the relationship curve between the speed and the combined resistance value in Fig. 5, this tendency increases the combined resistance value and increases the voltage. It can be seen that the smaller the value, the greater the value.

Therefore, from the curve of FIG. 5, 50 Hz, 60
Hz, maximum values R ₂ and R ₂ ′ / minimum value R _{1 of} combined resistance values for obtaining the required predetermined speeds v _{1 to} v ₂ , respectively.
Since R ₁ ′ is determined, the same speed can be set at 50 Hz and 60 Hz, and its concrete circuit configuration is as follows.

The variable resistor is a rotary variable resistor 2
8 is used, and between the terminal whose resistance value decreases by clockwise rotation and between the terminal whose resistance value decreases by counterclockwise rotation are used for 50 Hz and 60 Hz, respectively.

Here, the selection is made by the changeover switch 29 for facilitating the changeover operation, but the same applies to the connection change of the lead wire.

Next, the fixed resistor 30 is connected in series to the resistor between the terminal for 50 Hz.

A fixed resistor 31 is connected in parallel to the resistor between the 60 Hz terminal and a fixed resistor is further connected in series.

The rotary variable resistor 28 used, and
The resistance values of the fixed resistors 30, 31, 32 are determined so that a combined resistance value as shown in the following Table 1 is obtained under the condition that the same speed is obtained at 50 Hz and 60 Hz depending on the performance of the electric motor.

1. Conditions for combined resistance

[0042]

[Table 1]

2. Determination of each resistor Resistance value of fixed resistor 30 = R ₁ (Ω) ... Resistance value at maximum speed at 50 Hz Maximum resistance value of rotary variable resistor 28 = R ₂ -R ₁ (Ω) ...
Combined resistance with R ₁ is resistance value at the lowest speed at 50 Hz Resistance value of fixed resistor 32 = R ₁ ′ ... Resistance value at maximum speed at 60 Hz Resistance value of fixed resistor 31: (R ₂ −R ₁ ) ( R ₂ ′-
R ₁ ′) / (R ₂ −R ₁ ) − (R ₂ ′ −R ₁ ′) ... The combination of the maximum resistance value of the rotary variable resistor 28 and the fixed resistors 31 and 32 is 60 Hz at the lowest speed. Resistance value According to this, in the case of 50 Hz, the minimum speed is
The rotary variable resistor 28 is set to the maximum resistance value, and the combined resistance value of the rotary variable resistor 28 and the fixed resistor 30 is maximized.

On the other hand, when the maximum speed is set, the rotary variable resistor 28 is shorted to the minimum resistance value, that is, 0Ω, so that the combined resistance value is minimized only for the fixed resistor 30.

Next, in the case of 60 Hz, at the lowest speed, the rotary variable resistor 28 is set to the maximum resistance value, and the combined resistance value of the rotary variable resistor 28 and the fixed resistors 31 and 32 is maximized. To do.

On the other hand, at the maximum speed, the rotary variable resistor 28 is shorted to the minimum value of 0Ω, and only the fixed resistor 32 is minimized.

Therefore, the rotary variable resistor 28 to be operated is
Is the maximum resistance value or the minimum resistance value, 50H
The applied voltage to the electric motor 1 can be set to be the same at z and 60 Hz, that is, the same speed can be obtained.

Next, the case of performing the high-speed hoisting operation will be described. In response to a high-speed command from the second-step pushing operation for hoisting the pushbutton switch 20, the first-stage contact 2
1a is closed as it is, and the contact 21 of the second stage is further added.
Since A is closed, the high speed variable operation unit 33 is connected in parallel to the low speed variable operation unit 27. That is, as described above, since the low-speed variable operation unit 27 in which the combined resistance value is set so that there is no difference between the power supply frequencies of 50 Hz and 60 Hz is connected in parallel, and because of the high-speed side, the difference between 50 Hz and 60 Hz is also included. Is reduced,
The speed setting on the high speed side can be made almost the same, and therefore, the speed setting is realized regardless of the frequency for both the low speed and the high speed.

Up to now, the hoisting operation has been described, but it goes without saying that the hoisting operation functions in exactly the same manner.

As described above, as shown in FIG. 6, even if the power source frequency is 50 Hz, the push button switch 20 receives the low speed command of the first step and the high speed command of the second step, respectively.
Even at 0 Hz, the rotary variable resistor 28
And by changing the resistance value of the variable resistor 34,
It is possible to arbitrarily set the speed within a predetermined range.
Regarding the configuration of the parts, the rotary variable resistor 28 for low speed and the changeover switch 29 are basically operated and set initially according to the power supply frequency and the special purpose, and must always be operated. Therefore, the high-speed variable operation unit 33 including the variable resistor 34 on the high-speed side is provided in the hoisting machine body as shown in FIG. Since there are many opportunities for operation by the user, and therefore it is necessary for the customer to be able to easily set it, the push button switch section 20 should be provided, and the push button switch section that is the customer's hand should have the minimum necessary parts. It is designed to be easily handled roughly and to minimize damage such as collisions with walls, etc. and damages that may occur during disassembly and inspection.

As another embodiment, FIG. 7 shows a case where the power source frequencies are 50 Hz and 60 Hz, and two variable resistors 37 and 38 for low speed are used and the resistance value is limited by the fixed resistors 39 and 40. However, it has the drawback that it can be used properly and obtains the same performance, but it requires two variable resistors and its mounting structure is complicated.

[0052]

The present invention is as described above, and as is apparent from the illustrated embodiments, the present invention provides the following effects.

Generally, for the purpose of mitigating the impact when the luggage is leaving and landing, and for avoiding the dangerous situation where the luggage shakes, low speed operation is performed at the time of start / stop and high speed at the time of other transportation. For improving work efficiency as operation, transporting dangerous substances such as chemicals and explosives, water, etc., precision assembly of parts, matching of dies such as press dies, dipping of parts into plating layer, etc. Especially, it is necessary to start and stop at a low speed, and the speed cannot be generally determined depending on the application.

Further, in other carrying processes,
It is dangerous to swing the luggage because it is a dangerous object or a large heavy object, and because the traveling height is low, the workability is better at low speeds. There is a need to reduce the speed depending on the application.

In this respect, according to the present invention, two kinds of speeds, low speed and high speed, can be freely used by operating the push button switch. Moreover, both low speed and high speed can be used by operating the variable resistor. It is possible to arbitrarily set the optimum speed for.

Also, regarding the speed difference due to the difference in the voltage applied to the motor due to the power source frequencies of 50 Hz and 60 Hz,
Using a rotary variable resistor, taking advantage of its structure and characteristics,
The terminals can be shared by using terminals at 50 Hz and 60 Hz by using a changeover switch, etc. Further, by connecting the fixed resistors in series / parallel, the combined resistance of each can be the same at 50 Hz and 60 Hz. By setting so that the resistance value becomes like this, with a simple structure,
By a simple means, a constant speed setting independent of frequency is realized.

Further, the variable resistor for high speed, which is frequently operated, is provided in the push button switch part which is at the customer's hand to improve the usability, while the rotary variable resistor for low speed and the changeover switch are the power source. Due to the nature of initial operation depending on the frequency and special use, the push-button switch part that is built into the hoisting machine body and may be damaged by the customer's hand and may be damaged should be kept to the minimum necessary parts. By doing so, the structure is designed to minimize damage in the unlikely event, and reliability is ensured.

As described above, after completely solving the problems of the prior art, the usability is further improved and the performance is stable.

[Brief description of drawings]

FIG. 1 is an electric circuit diagram showing an embodiment of the present invention.

FIG. 2 is an external view of an electric chain block incorporating the electric circuit shown in FIG.

3 is a structural explanatory view of a rotary variable resistor and a changeover switch 29 shown in FIG.

FIG. 4 is a voltage waveform diagram of power supply frequencies of 50 Hz and 60 Hz.

FIG. 5 is a relationship curve diagram between speed and combined resistance value.

FIG. 6 is an operation explanatory view of the electric chain block shown in FIG.

FIG. 7 is an electric circuit diagram showing another embodiment according to the present invention.

FIG. 8 is an external view of a general electric chain block according to the related art.

FIG. 9 is an external view of a conventional double speed electric chain block.

FIG. 10 is an external view of a conventional variable speed electric chain block.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electric motor, 2 ... Transmission article storage part, 3 ... Upper hook, 4 ... Cable, 5 ... Chain, 6 ... Lower hook, 7 ... Lifting tool, 8 ... Operation part, 9 ... Luggage, 10 ... Double winding electric motor, 11 ... Lead wire for multiple poles (8 poles), 12 ... Lead wire for small poles (2 poles), 13
… Motors for hoisting and lowering, 14… Magnetic contactors for low and high speeds, 15… Two-step motion pushbutton switches, 16
... Operation unit having push button switch and speed designation operation unit,
17 ... Winding / lowering command operation button, 18 ... Winding / lowering command, and electric motor applied voltage control unit,
19 ... Control part, 20 ... Operation part according to the present invention, 21 ... Winding command two-step motion push button, 22 ... Unwind command two-step motion push button, 23 ... Power supply, 24 ... Unwinding relay, 25 ... Winding relay, 26 ... Voltage control circuit section, 27 ... Low speed variable operation section, 28 ... Rotary variable resistor, 29 ... Changeover switch, 30 ... Fixed resistor, 31 ... Fixed resistor, 32 ... Fixed Resistor, 33 ... High speed variable operating part, 34 ... Variable resistor, 35 ... Break resistor, 36 ... Rectifier, 37, 38 ... Variable resistor, 39, 40 ... Fixed resistor.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H02P 7/292 E 4238-5H

Claims (1)

[Claims] 1. A double-speed electric machine in which an operation box is hung from a main body of an electric hoist via a cable, and the operation box is operated to perform a hoisting / unwinding operation at two speeds, high speed and low speed. In the hoisting machine, the high speed side is configured to control the voltage of the electric motor by changing the resistance value of the variable resistor provided in the operation box, and to change the rotation speed to change the speed, and Similarly, on the low speed side, it is configured to be controlled by the variable resistor provided in the hoisting machine body.
A rotary variable resistor is used for the variable resistor on the low speed side, and a switch or connection change is made between the terminal whose resistance value decreases with clockwise rotation and between the terminal whose resistance value decreases with counterclockwise rotation. Either one, for example, a fixed resistor is connected in series to the resistance between the terminals, and the other, for example, a fixed resistor is connected in parallel to the resistance between the terminals, and further, As a circuit configuration in which a fixed resistor is connected in series to a parallel resistance circuit, the terminal-
Double speed variable speed type having a control means for arbitrarily determining the maximum and minimum values of the combined resistance value of the two circuits consisting of the side and the terminal-side in accordance with the required circuit constant. Electric hoist.