JP2702387B2 - Inverter hoist and inverter crane equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inverter hoist and an inverter crane device equipped with a braking resistance device for heat-converting and consuming regenerative current of an electric motor.

[0002]

2. Description of the Related Art As a known example of a conventional inverter hoist equipped with a braking resistance device, for example,
Although the technology described in Japanese Patent Application Laid-Open No. 8995/1989 can be cited, a conventional technology will be described with reference to FIGS. 2 to 6 in order to clarify the gist of the present invention.

FIG. 2 shows an overall configuration of a conventional inverter hoist, and FIG. 3 shows an example of a braking resistor device which can be considered from the technique described in Japanese Utility Model Laid-Open No. 59-8955.

When an operation command for raising or lowering a load is given by the operation input device 2, the signal is taken into the control unit 4.

[0005] The control unit 4 controls the inverter device 3 and the brake device 10 based on information from the operation input device 2 to vary the rotation speed of the electric motor 9 continuously or stepwise.

As shown in FIG. 3, a braking resistor device 19 estimated from the technique described in Japanese Utility Model Laid-Open Publication No. Sho 59-8995 has at least one winding resistor 12, a supporting member 14 supporting the same, and a hoist. It is considered to be composed of a mounting plate 15 to the main body, a fan 6 for cooling the wire wound resistor 12, and a contact protection cover 13 for preventing the heat radiation effect of the wire wound resistor 12 and preventing external contact. .

The braking resistance device 19 is used in the following cases.

That is, in the hoisting / unwinding operation pattern shown in FIG. 4, there are a decelerating operation and a hoisting operation of the hoisting operation indicated by oblique lines.

In the area shown by the diagonal lines, the motor 9
Causes a power generation phenomenon, thereby generating regenerative energy, and a regenerative current flows between the electric motor 9 and the inverter device 3.

The conventional braking resistor device 19 consumes this regenerative current by converting it into thermal energy by means of the winding resistor 12 for high power.

As shown in FIG. 5, a winding resistor is formed by winding a metal wire 17 around a cylinder 16 made of a material such as porcelain or synthetic resin, and covering this with a protective film 18 such as enamel, synthetic resin, or cement. Things.

The reason why the wound resistor 12 is used as a medium for the heat conversion process is that errors due to temperature are small, heat resistance is excellent, and
This is because there is an advantage that it can endure a little vibration and impact. However, on the other hand, since the size of the resistor of the wire wound resistor 12 is large, the braking resistance device 19 is inevitably large, and since the device is large and dissipates high heat during use, it is attached to the hoist body. There was a drawback that the position was restricted.

[0013]

As described above, in the conventional inverter hoist, the regenerative energy conversion medium uses a winding resistor having a large resistor body as a regenerative energy conversion medium. There is a problem that the size of the brake resistance device is increased, and the mounting position of the braking resistance device to the hoist body is restricted, which makes the operation difficult.

It is an object of the present invention to reduce the size of the braking resistor and the mounting of the braking resistor, and to provide a certain degree of freedom in mounting the braking resistor to the mounting of the braking resistor. An inverter hoist and an inverter crane device.

[0015]

SUMMARY OF THE INVENTION The object of the present invention is to provide a so-called regenerative current heat conversion consuming medium for converting regenerative current into thermal energy, comprising a metal plate resistor having a small resistor as a component. Inverter hoist,
Alternatively, this can be achieved by mounting on an inverter hoist traversing device or / and a saddle device of an inverter crane device.

[0016]

According to the present invention, as a heat conversion consuming medium for regenerative current for converting regenerative current to thermal energy, a braking resistor device having a metal plate resistor having a small resistor as a component is provided as an inverter hoist, Alternatively, by mounting the brake resistance device and / or the saddle device on the inverter hoist traverse device and / or the saddle device of the inverter crane device, the size of the braking resistance device and thus the mounting of the braking resistance device can be reduced. It has a certain degree of freedom, and can be mounted more easily than before.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to FIG. 1 and FIGS.

FIG. 1 shows the overall structure of the inverter hoist.
FIG. 7 shows a specific example of the braking resistance device.

When an operation command for raising or lowering the load is given by the operation input device 2, the signal is taken into the control unit 4.

The control unit 4 controls the inverter device 3 and the brake device 10 based on information from the operation input device 2 to vary the rotation speed of the electric motor 9 continuously or stepwise.

In the present embodiment, as shown in FIG. 7, the braking resistance device 8 comprises at least one metal plate resistor 5, a support member 24 supporting the same, a mounting plate 22 for the hoist body, and a metal plate resistor. 5, thermal relay 23 for preventing overheating and burning
One or more fans 6 for cooling the metal plate resistors 5;
And a contact protection cover 21 for preventing the heat radiation effect of the wire wound resistor 5 and preventing external contact.

This braking resistance device 8 is used in the following cases.

That is, in the hoisting / unwinding operation pattern shown in FIG. 8, there are a decelerating operation and a hoisting operation of the hoisting operation indicated by oblique lines.

In the hatched area, the motor 9
Causes a power generation phenomenon, thereby generating regenerative energy, and a regenerative current flows between the electric motor 9 and the inverter device 3.

The braking resistance device 8 consumes the regenerative current by converting it into heat energy by the metal plate resistor 5.

FIG. 9 shows the structure of the metal plate resistor 5.

The metal plate resistor 5 includes a lead wire 28 for transmitting a regenerative current to the resistor, a metal wire 27 wound from the lead wire 28 to the insulating plate 26, a metal plate 25, and the like.

The regenerative current transmitted through the lead wire 28 is
The energy is converted into heat energy by the metal wire 27 wound around the insulating plate 26.

The converted heat energy is transmitted to the metal plate 25 sandwiching the insulating plate 26 from above and below and dissipated into the atmosphere.
It is consumed with.

The metal wire 27 is wound around the insulating plate 26,
Alternatively, the reason why the metal wire 27 is sandwiched between the insulating plates 26 from above and below is to prevent a short circuit caused by the metal wire 27 directly touching the metal plate 25.

As described above, in the portion of the metal plate resistor 5, the thermal energy converted by the metal wire 27 is transferred to the metal plate 25.
To diverge.

The metal plate 25 has a higher thermal conductivity than porcelain, synthetic resin, or the like, which is a heat energy dissipating member for winding resistance. The heat conversion efficiency is improved as compared with that of the conventional product.
It could be reduced to about 3.

Further, by mounting a thermal relay 23 as a heat monitoring device in the braking resistance device 8, it is possible to prevent abnormal heating of the resistance due to excessive use.

[0034] In contrast, conventional braking resistor device, since those not subjected to temperature sensing for overheating burnout prevention is etc.殆, resistor in special circumstances by frequency of use excessive further braking resistor There was a risk of overheating and burning of the device.

A fan 6 for cooling the metal plate resistor 5
Power from the main power line, and when the main power is
By constantly rotating, the cooling efficiency of the metal plate resistor 5 can be increased, and by increasing the cooling efficiency in this way, there is an advantage that the capacity of the resistor used can be reduced.

On the other hand, in the conventional braking resistance device, as described in Japanese Utility Model Application Laid-Open No. 59-8995, the fan is rotated by a part of the regenerative current to cool the resistor. Since the fan rotates using the regenerative current, it does not rotate during hoisting acceleration, hoisting at a constant speed, or stopping, as shown in FIG.

However, when the regenerative current flows through the winding resistor, the regenerative energy is not instantaneously converted into heat and dissipated.

It takes a certain amount of time before the regenerative current is converted into thermal energy by the winding resistor and the thermal energy is radiated from the resistor into the surrounding atmosphere.

For this reason, as shown in FIG. 6, in the winding resistor, the heat energy generated by the regenerative current generated during the deceleration operation of the hoisting operation and during the hoisting operation increases during hoisting acceleration, during constant speed hoisting, or It is fully conceivable that the heat will be dissipated at the time of stoppage.Thus, it is economically inexpensive to rotate the fan with a part of the regenerative current,
It can be seen that the cooling efficiency is clearly lower than when the fan is constantly rotated.

In this embodiment, the case where the braking resistance device 8 having the above-described configuration is used for heat conversion consumption of regenerative energy during the hoisting and lowering operations of the inverter hoist 11 has been described. The device 8 is shown in FIG.
It can also be used for regenerative energy heat conversion consumption when the inverter hoist traverses the saddle or the saddle travels.

Hereinafter, a case where the present invention is applied to an inverter crane device will be described.

In FIG. 10, the crane saddle device 3
2 and 48 connect the inverter hoist 39 and the traversing device 50 incorporated in the garter 42 to the saddle motor 31,
46 moves the rails 29 and 45 in the e or f direction.

The saddle motors 31 and 46 are controlled to required frequency, voltage and current characteristics by an instruction from the operation input device 36 and the inverter device 43.

FIG. 11 shows an operation pattern of the crane saddle devices 32 and 48.

The traversing device 50 moves the inverter hoist 39 along the garter 42 in the direction c or d by the traversing motor 41.

The traversing motor 41 is driven by the instruction from the operation input device 36 and the inverter device 35 to control the required frequency and frequency.
Controlled by voltage and current characteristics.

FIG. 11 shows an operation pattern of the traversing device 50.

Then, the inverter hoist 39 moves the load in the a direction or the b direction by the hoisting / lowering motor 40.

The hoisting / lowering motor 40 is controlled to required frequency, voltage and current characteristics by an instruction from the operation input device 36 and the inverter device 38.

FIG. 8 shows the operation pattern during winding and unwinding.

The inverter crane device moves the crane saddle devices 32 and 48 in the e and f directions, moves in the c and d directions by the traversing device 50, and operates the inverter hoist 39 in response to an operation instruction from the operation input device 36. The movement in the a and b directions due to the above can be performed in parallel.

In each of the operation patterns shown in FIG. 11, the hatched portion is a portion that generates regenerative energy, and is consumed by the braking resistance devices 44 and 34 for heat conversion.

In this embodiment, the inverter device 3
5, 38, 43 and braking resistance devices 34, 37, 44 are separately mounted for running, traversing and hoisting, respectively, but one inverter device and one braking resistance device are used for running and traversing. Thus, two inverter devices and two braking resistance devices may be arranged for running, traversing, and hoisting and hoisting as a whole.

In the illustrated embodiment, as shown in FIG. 9, the insulating plate 26 around which the metal wire 27 is wound is sandwiched between two insulating plates 26 from above and below, and the metal plate 25 Although it takes the form of being sandwiched between
It suffices if the regenerative energy is finally consumed along the metal plate as a heat dissipating member, and is not limited to the structure shown in FIG.

In the embodiment shown in the drawings, the metal plate resistance is flat, but may be, for example, a cylindrical shape or another shape. In addition, the size of the regenerative energy conversion medium can be reduced as compared with a braking resistance device using a winding resistor having a large resistor size.

Furthermore, in the illustrated embodiment, the metal plate resistors 5 are vertically stacked as shown in FIG. 7, but they may be arranged in a plane.

Further, in the illustrated embodiment, the thermal relay 23 is used as the temperature monitoring device, but any other device may be used as long as it monitors the temperature.

Further, in the illustrated embodiment, the temperature monitoring device is attached to the protective cover 21 of the braking resistance device 8,
It may be mounted outside the metal plate resistor 5 or inside the metal plate resistor 5.

[0059]

According to the present invention, as a heat conversion consuming medium for regenerative current for converting regenerative current to heat energy,
By mounting a braking resistance device having a metal plate resistor having a small size as a constituent element on an inverter hoist or an inverter hoist traversing device or (and) a saddle device of an inverter crane device, the braking resistance device and, consequently, the braking resistance device are reduced. It is intended to reduce the size of the mounting body and to have a certain degree of freedom in mounting the braking resistance device to the braking resistance device mounting body, so that the mounting work can be performed more easily than before. The two effects of miniaturization and improvement of assembly workability can be simultaneously achieved.

Further, by providing the braking resistance device with an overheating burnout prevention function structure, it is possible to prevent abnormal heating of the resistance due to excessive use.

Further, by providing the braking resistance device with a function of always forcibly cooling the heat conversion / consumption medium from regenerative current to thermal energy, the cooling efficiency of the metal plate resistor can be increased. By increasing the cooling efficiency, the capacity of the resistor used can be reduced.

[Brief description of the drawings]

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

FIG. 2 is a block diagram of a conventional inverter hoist.

FIG. 3 is a perspective view showing an example of a braking resistance device that can be considered from a known example.

FIG. 4 is an explanatory diagram of an operation pattern of a conventional inverter hoist.

FIG. 5 is a perspective view of a wire wound resistor.

FIG. 6 is a diagram showing a relationship between an operation pattern of an inverter and a surface temperature of a braking resistor.

FIG. 7 is a perspective view showing a specific example of a braking resistance device incorporated in the inverter hoist of the present invention.

FIG. 8 is an explanatory diagram of an operation pattern of the inverter hoist according to the embodiment.

FIG. 9 is an exploded perspective view showing a structure of a metal plate resistor.

FIG. 10 is a perspective view showing the entire configuration of the inverter type crane device.

FIG. 11 is an explanatory diagram of an operation pattern of the inverter type crane device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Main power supply, 2 ... Operation input device, 3 ... Inverter device,
Reference numeral 4: control unit, 5: metal plate resistance, 6: fan, 7: heat monitoring device, 8: braking resistance device, 9: electric motor, 10: brake device, 11: inverter hoist.

Claims (8)

(57) [Claims] An operation input device for giving an operation command for moving a load up and down, an electric motor as a power source for moving the load up and down, a brake device for stopping driving of the electric motor, and a rotation of the electric motor In an inverter hoist including an inverter device that variably controls the speed, a control unit that controls an operation input device, a brake device, and an inverter device, and a braking resistance device that consumes a regenerative current from the electric motor, a regenerative current to heat energy is generated. An inverter hoist characterized in that a braking resistance device comprising a metal plate resistor as a component is mounted as a heat conversion consuming medium for conversion. 2. The inverter hoist according to claim 1, wherein the braking resistance device has a function of preventing overheating and burning. 3. The inverter hoist according to claim 1, wherein the braking resistance device is provided with a function of always forcibly cooling the heat conversion / consumption medium from regenerative current to heat energy. 4. An inverter crane device, wherein a braking resistance device having a metal plate resistor as a component is mounted as a heat conversion consuming medium for converting regenerative current of the traversing device into thermal energy when the inverter hoist traverses. Inverter crane device characterized by the above-mentioned. 5. The inverter crane device according to claim 1, wherein a braking resistance device having a metal plate resistor as a component is mounted as a heat conversion consuming medium for converting the regenerative current of the saddle device into thermal energy during saddle traveling. Inverter crane equipment. 6. In an inverter crane device, a metal plate resistor is used as a heat conversion consuming medium for converting regenerative current of the saddle device into heat energy when the inverter hoist traverses and the saddle device during saddle traveling. An inverter crane device equipped with a braking resistance device that performs the following. 7. in any one of claims 4-6, inverter crane apparatus characterized by comprising an overheat burnout protection structure to the braking resistor device. 8. A any one of claims 4-7, inverter crane, characterized in that to brake resistor device, equipped with a function to constantly forced cooling heat conversion consumption medium to the heat energy from the regenerative current apparatus.