JPH0127957B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides an electric chain block with an electric trolley in which either the electric trolley or the electric chain block can be independently operated at a set speed by inverter control. The present invention relates to a speed control device for an electric chain block with an electric trolley, which is capable of operating the electric chain block at a rated speed and simultaneously operating an electric trolley at a set speed under inverter control.

[Prior art]

Conventional electric chain blocks with electric trolleys do not have a device to adjust the traveling speed of the electric trolley and the lifting speed of the electric chain block, so the work efficiency during hoisting, lowering, and traveling transportation of loads is reduced. There was a problem that it was bad.

[Purpose and structure of the invention]

The object of the present invention is to provide a speed control device for an electric chain block with an electric trolley that can advantageously solve the above-mentioned problems. One inverter 1 is provided in the power supply circuit, the motor 3 of the electric trolley 2 is connected to the power supply via the inverter 1, and the motor 5 of the electric chain block 4 is connected to the power supply via the inverter 1. The control circuit of the electric chain block with an electric trolley, which is connected to the power supply without going through the inverter 1, includes each of the motors 3 and 5.
an independent operation state in which power is supplied to only one of them via the inverter 1, and a simultaneous operation state in which power is supplied to the motor 3 of the electric trolley via the inverter 1 and to the motor 5 of the electric chain block 4 not via the inverter 1. A changeover switch _S1 is provided for switching between the two states, and a timer relay TR is provided which operates when the electric trolley is decelerated by the inverter 1 and delays the power supply to the motor 3 of the electric trolley 2.
The present invention provides a speed control device for an electric chain block with an electric trolley, characterized in that the speed reduction device in the electric chain block 4 is provided with a mechanical brake for preventing hanging loads from falling.

〔Example〕

Next, the present invention will be explained in detail using illustrated examples.

The drawing shows one embodiment of the present invention, in which an electric trolley 2 running along a running rail 6 has a motor 3 consisting of a brake motor, and is suspended and supported by a frame 7 of the electric trolley 2. The electric chain block 4 is equipped with a motor 5 consisting of a brake motor and a mechanical brake for preventing hanging loads from falling, which is provided in a speed reduction device, and a control circuit storage box 8 and an inverter 1 are attached to the frame 7. Furthermore, at the lower end of the operation cable 9 hanging down from the connection box 8, there is an operation box 1.
0 is connected. Further, each of the motors 3 and 5 is configured so that the brake is automatically operated when the power to the motor is cut off, and the brake is automatically released when the motor is connected to the power. brake motor is used.

The gear reduction device and mechanical brake of the electric chain block 4 will be explained with reference to FIGS. 3 to 5. A drive shaft 12 connected to a rotor shaft 11 of a motor 5 is supported by a casing 13 via a bearing. A hollow driven shaft 14 that has passed through the drive shaft 12 is rotatably supported by the casing 13 via a bearing, and a load sheave 16 around which a load chain 15 is wound is integrally provided on the hollow driven shaft 14. , a large diameter driven gear 17 is fixed.

An intermediate shaft 18 arranged parallel to the drive shaft 12
is rotatably supported by a casing 13 via a bearing, a small diameter intermediate drive gear 19 that meshes with the large diameter driven gear 17 is fixed to the intermediate shaft 18, and a small diameter drive gear provided at the end of the drive shaft 12. A large-diameter intermediate driven gear 21 and a brake tightening disk 22 that mesh with the gear 20 are screwed together with the brake screw of the intermediate shaft 18, and are further formed by the large-diameter intermediate driven gear 21, the brake tightening disk 22, and their bosses. An annular ratchet wheel 23 and an annular friction plate 24 disposed on both sides thereof are fitted into the annular groove, and a claw piece 25 that engages with the ratchet wheel 23 is pivotally attached to the casing 13. is engaged with a spring 26 which acts to engage the ratchet wheel 23.
a large-diameter intermediate driven gear 21 and a brake tightening disc 22 screwed onto the brake screw of the intermediate shaft 18;
A ratchet wheel 23 and a friction plate 2 interposed between them
4 and a pawl piece 25 engaged with the pawl wheel 23 by a spring 26 constitute a mechanical brake, and the weight of the suspended load causes the load chain 15,
When the intermediate shaft 18 is rotated by a certain angle via the load sheave 16, the large-diameter driven gear 17, and the small-diameter intermediate drive gear 19, the brake tightening disc 22 screwed onto the brake screw of the intermediate shaft 18 is rotated by a large diameter. The large diameter intermediate driven gear 21 and the brake tightening disk 22 tighten the ratchet wheel 2.
3 and the friction plate 24 are gripped and integrated, and the claw wheel 23 is engaged with a claw piece 25 that prevents the suspended load from rotating in the falling direction, so a mechanical brake is activated to prevent the suspended load from falling. is prevented.

7 to 9 show speed control circuits of an electric chain block with an electric trolley, in which the motor 5 in the electric chain block is
The three-phase signal is connected to the A contact MC4-a of the hoisting magnetic contactor MC4, the A contact MC5-a of the lowering magnetic contactor MC5, and the A contact MC1-a of the inverter main circuit power-on magnetic contactor MC1. Power supply R, S, T
The brake motor 3 of the electric trolley is connected to the main circuit output terminals U, V, and W of the inverter 1 via the A point MC2-a of the electromagnetic contactor MC2 for powering on the chain block motor, and the brake motor 3 of the electric trolley is connected to the trolley motor It is connected to the main circuit output terminals U, V, and W of the inverter 1 via the A contact MC3-a of the power-on magnetic contactor MC3, and is further connected to the main circuit output terminals U, V, and W of the inverter 1.
The main circuit power terminals R ₁ , S ₁ , T ₁ are the A contacts
The three-phase power supply R, S, and T are connected between MC1-a and MC4-a, and the inverter control power supply terminals R ₂ and T ₂ of the inverter 1 are connected to the A contact point.
It is connected to power supplies R and T before MC1-a.

Frequency setting terminal V ₁ in inverter 1,
V ₂ and V ₃ are connected to the variable resistor VR for speed adjustment,
In addition, the forward rotation terminal SF of the inverter 1 is connected to the A contact R1-a2 of the inverter control hoisting relay R1 and the A contact R of the inverter control forward running relay R3.
One end of the normal rotation (hoisting, forward running) control circuit consisting of a parallel circuit with 3-a2 is connected, and the A contact R2-a2 of the inverter control lowering relay R2 is connected to the reverse circuit terminal SR of the inverter 1. One end of the reverse (lowering, backward traveling) control circuit consisting of a parallel circuit with the A contact R4-a2 of the inverter-controlled backward traveling relay R4 is connected, and the inverter 1
One end of the B contact R5-b2 of the travel slow stop relay R5 is connected to the acceleration/deceleration switching terminal Ta.
The other end of the B contact R5-b2, the other end of the normal rotation control circuit, the other end of the reverse rotation control circuit, and the terminal C1 of the inverter 1 are connected to each other. Further, the inverter control power supply terminal _R2 of the inverter 1 is connected to an abnormality detection common terminal Tc, and the abnormality detection common terminal Tc is connected to an abnormality detection B contact output terminal Tb.

The control circuit of the electric chain block with electric trolley consists of a main circuit power supply circuit, an operation method switching circuit, a hoisting circuit, a lowering circuit, a forward running circuit,
It has a reverse travel circuit, a chain block motor power supply circuit, and a travel timer circuit, and the main circuit power supply circuit includes a push button main circuit power switch _S2 connected in series and a magnetic contactor MC1 for main circuit power supply. The main circuit power-on circuit is connected to the power line T and the abnormality detection B contact output terminal Tb of the inverter 1.

The operation mode switching circuit is composed of a simultaneous operation/single operation switching switch _S1 consisting of a push button switch connected in series, and an operation mode switching relay R6, and the hoisting circuit is composed of a push button switch connected in series. Hoisting switch _S3 , hoisting limit switch LSU, inverter control hoisting relay R1,
B contact R6-b1 of operation method switching relay R6,
B contact R of inverter-controlled forward running relay R3
3-b1, inverter-controlled reverse travel relay R4
B contact R4-b1 of the travel slow stop relay R5, and the R1, R6-b1, R
A hoisting magnetic contactor MC4 connected in parallel to the series circuit of 3-b1, R4-b1, and R5-b1,
It is constituted by a series circuit of A contacts R6-a1 of the operation mode switching relay R6.

The lowering circuit consists of a push-button lowering switch S ₄ and a lowering limit limit switch connected in series.
B contact R6-b2 of LSD, inverter control lowering relay R2, operation method switching relay R6, and B contacts R3-b1, R4- shared with the hoisting circuit.
b1, R5-b1 and the above R2, R6-b2, R
A lowering magnetic contactor MC5 connected in parallel to the series circuit of 3-b1, R4-b1, and R5-b1,
It is composed of a series circuit of A contacts R6-a2 of the operation method switching relay R6, and the hoisting switch _S3
and the lowering switch _S4 are configured so that when one is turned on, the other is turned off in conjunction.

The forward running circuit includes a forward running switch _S5 connected in series, an inverter-controlled forward running relay R3,
B contact R2- of inverter control lowering relay R2
b, B contact R of inverter control hoisting relay R1
1-b, and the reverse circuit includes a reverse switch _S6 connected in series, an inverter-controlled reverse relay R4, and B contacts R2-b and R1-b shared with the forward circuit. The forward switch _S5 and the backward switch _S6 are configured such that when one is turned on, the other is turned off in conjunction with the forward switch S5.

The chain block motor power-on circuit consists of A contacts R1-a1 of the chain block motor power-on electromagnetic contactor MC2 and inverter control hoisting relay R1 connected in series, and the A contact R.
1-a1 and A contact R2-a1 of the inverter control lowering relay R2 connected in parallel to the inverter control lowering relay R2.

The running timer circuit has an A contact R3-a of an inverter-controlled forward running relay R3 connected in series.
1. B contact T-b of timer relay TR, A contact R4-a1 of inverter-controlled reverse travel relay R4 connected in parallel to travel slow stop relay R5 and said A contact R3-a1, travel slow stop relay R4. Relay R
5 A contact R5-a1 and running slow stop relay R5
A first circuit-1 consisting of a trolley motor power-on electromagnetic contactor MC3 connected in parallel to the A contact R5-a2 of the travel slow stop relay R5 connected in series, and an inverter-controlled reverse travel relay R
B contact R4-b2 of 4, B contact R3-b2 of inverter-controlled forward running relay R3, timer relay
It is constituted by a second circuit -2 consisting of a TR, and each circuit -1, -2 is connected to a power supply line T and a main circuit power terminal _R1 of the inverter 1.

A changeover switch S1 having the variable resistor VR for speed adjustment, a pushbutton _S1 -a for simultaneous operation, and a pushbutton _{S1 -} b for independent operation, and a pushbutton _S2 -a for powering on.
and a power switch S ₂ having a power-off push button S ₂ -b, a hoisting switch S ₃ , a hoisting switch S ₄ ,
The forward switch _S5 and the reverse switch _S6 are provided in the operation box 10, and the limit switch LSU for limiting hoisting and the limit switch LSD for limiting hoisting are attached to the chain block body (not shown). When the winding is completed to the upper limit, a limit switch for restricting winding is activated by a striker 29 made of a helical spring mounted on a support fitting 28 that supports the lower hook 27.
When the LSU is operated and lowered to a predetermined lowering limit, a lowering limit limit switch LSD is operated by a striker (not shown) attached to the load chain 15.

B contact R5- of the running buffer stop relay R5
b2 is a contact for switching acceleration/deceleration, and this contact R5
-b2 is on, the acceleration/deceleration of the motor 5 of the electric chain block is set, and its contact R5-
When b2 is off, the acceleration/deceleration of the motor 3 of the electric trolley is set. The abnormality detection B contact output terminal Tb in the inverter is turned off when an abnormality occurs.

Next, the operation of the speed control circuit will be explained.

First, push button S ₂ -a of main circuit power switch S ₂
When you press the power switch _S2 to turn on, the magnetic contactor MC1 for turning on the main circuit power is energized.
Since the A contact MC1-a of the electromagnetic contactor MC1 is turned on, the inverter 1 is powered on.

Next, press the independent operation pushbutton _S1 -b of the simultaneous operation/independent operation changeover switch _S1 to turn off the changeover switch _S1 , and then press the hoisting switch _S3 to turn on the inverter control. Since the hoisting relay R1 is energized and the B contact R1-b of the inverter-controlled hoisting relay R1 in the forward traveling circuit and the backward traveling circuit is turned off, the electric trolley cannot be driven forward or backward. , On the other hand, A of the inverter control hoisting relay R1 in the chain block motor power supply circuit.
Contact R1-a1 is turned on, magnetic contactor MC2 for powering on the chain block motor is excited, and A contact MC2-a of the magnetic contactor MC2 is turned on, and the inverter in the forward rotation control circuit of inverter 1 is turned on. Since the A contact R1-a2 of the control hoisting relay R1 is turned on, power is applied to the motor 5 of the electric chain block via the inverter 1, the motor 5 rotates forward, and the electric chain block starts hoisting. be driven.

In addition, when the changeover switch _S1 is in an individual operation state, that is, in a state where it is turned off, and the lowering switch _S4 is pressed to turn on, the inverter control lowering relay R2
is excited, and the B contact R2-b of the inverter-controlled lowering relay R2 in the forward traveling circuit and the backward traveling circuit is turned off, so the electric trolley cannot travel forward or backward; A contact R of inverter control lowering relay R2 in the motor power supply circuit
2-a1 is turned on, the electromagnetic contactor MC2 for powering on the chain block motor is energized, the A contact of the electromagnetic contactor MC2 is turned on, and the inverter control lowering in the reverse control circuit X of the inverter 1 is turned on. Since the A contact R2-a2 of the relay R2 is turned on, power is applied to the motor 5 of the electric chain block via the inverter 1, the motor 5 is reversed, and the electric chain block is driven down.

Next, when the forward switch _S5 is pressed and turned on with the changeover switch _S1 in the independent operation state, that is, in the state of being turned off, the inverter-controlled forward travel relay R3 is energized, and the Since the B contact R3-b1 of relay R3 is turned off, the electric chain block cannot be hoisted or hoisted even if hoisting switch _S3 and hoisting switch _S4 are pressed.

On the other hand, when the inverter-controlled forward running relay R3 is energized, the A contact R3-a1 of the relay R3 in the running timer circuit is turned on.
Relay R5 for running slow stop and electromagnetic contactor MC3 for trolley motor power-on are energized, and A contacts R5-a1 and R5-a2 of relay R5 are turned on, and A contact R5-a1 is turned on. Therefore, the first circuit-1 of the running timer circuit is self-held, and furthermore, the B contact R5-b1 of the relay R5 in the hoisting circuit and the lowering circuit is turned off, and the two B contacts R3-b1, R5- b1
2 to prevent hoisting and lowering due to turning off.
heavily interlocked.

In addition, the magnetic contactor MC3 for turning on the trolley motor power
At the same time that the A contact MC3-a of the inverter 1 is turned on, the A contact R3-a2 of the inverter control advance relay R3 in the forward rotation control circuit of the inverter 1 is turned on, so power is supplied to the motor 3 of the electric trolley via the inverter 1. is turned on, the motor 3 rotates forward, and the electric trolley moves forward.

Next, when the forward switch _S5 is turned off, the inverter-controlled forward traveling relay R3 is demagnetized, and the relay R3 in the hoisting circuit and the lowering circuit is demagnetized.
The B contact R3-b1 of relay R5 in the hoisting circuit and the lowering circuit turns on.
Since 5-b1 remains in the off state,
It is not possible to hoist or lower the electric chain block.

On the other hand, the inverter-controlled forward running relay R
3 is demagnetized, the B contact R3-b2 of the relay R3 in the second circuit-2 of the travel timer circuit
is turned on and the timer relay TR starts operating, and at the same time, the A contact R3-a2 of the relay R3 in the forward rotation control circuit of the inverter 1 is turned off, and the deceleration of the motor 3 in the electric trolley is started.

After a certain period of time, which is the time set by the timer, B contact T-b is turned off by the excitation of timer relay TR, and relay R5 for running slow stop and magnetic contactor MC3 for turning on trolley motor power are demagnetized. The B contact R5-b1 of the relay R5 in the upper circuit and the lower circuit is turned on, and at the same time, the first circuit-1 of the traveling timer circuit is turned on.
and A contacts R5-a1 and R5-a2 of the relay R5 in the second circuit are turned off, and
By demagnetizing the electromagnetic contactor MC3, the A contact MC3-a of the electromagnetic contactor MC3 is turned off, and the power to the motor 3 is cut off.

After turning off the forward switch _S5 , the motor 3 is decelerated and stopped within the time set by the timer.

Next, when the reverse switch S ₆ is pressed and turned on with the changeover switch S ₁ in the independent operation state, that is, in the state of being turned off, the inverter-controlled reverse travel relay R4 is energized, and the Since the B contact R4-b1 of relay R4 is turned off, the electric chain block cannot be hoisted or hoisted even if hoisting switch _S3 and hoisting switch _S4 are pressed.

On the other hand, when the inverter-controlled reverse travel relay R4 is energized, the A contact R4-a1 of the relay R4 in the travel timer circuit is turned on.
Relay R5 for running slow stop and electromagnetic contactor MC3 for trolley motor power-on are energized, and A contacts R5-a1 and R5-a2 of relay R5 are turned on, and A contact R5-a1 is turned on. Therefore, the first circuit-1 of the running timer circuit is self-held, and furthermore, the B contact R5-b1 of the relay R5 in the hoisting circuit and the lowering circuit is turned off, and the two B contacts R3-b1, R5- b1
2 to prevent hoisting and lowering due to turning off.
heavily interlocked.

In addition, the magnetic contactor MC3 for turning on the trolley motor power
At the same time that the A contact MC3-a of the inverter 1 turns on, the A contact R4-a2 of the inverter control reverse relay R4 in the reverse control circuit of the inverter 1 turns on, so power is supplied to the electric trolley motor 3 via the inverter 1. When the motor 3 is turned on, the motor 3 rotates in the reverse direction, and the electric trolley moves backward.

Next, when the reverse switch _S6 is turned off, the inverter-controlled reverse travel relay R4 is demagnetized, and the relay R in the hoisting circuit and the lowering circuit is demagnetized.
The B contact R4-b1 of the relay R5 in the hoisting circuit and the hoisting circuit is turned on, but the B contact R5-b1 of the relay R5 in the hoisting circuit and the hoisting circuit remains in the off state. It is not possible to perform a downward drive.

On the other hand, the inverter-controlled backward traveling relay R
4 is demagnetized, the B contact R4-b2 of the relay R4 in the second circuit-2 of the travel timer circuit
is turned on and the timer relay TR starts operating, and at the same time, the A contact R4-a2 of the relay R4 in the reverse rotation control circuit of the inverter 1 is turned off, and the deceleration of the motor 3 in the electric trolley is started.

After a certain period of time, which is the time set by the timer, B contact T-b is turned off by the excitation of timer relay TR, and relay R5 for running slow stop and magnetic contactor MC3 for turning on trolley motor power are demagnetized. The B contact R5-b1 of the relay R5 in the upper circuit and the lower circuit is turned on, and at the same time, the first circuit-1 of the traveling timer circuit is turned on.
and A contacts R5-a1 and R5-a2 of the relay R5 in the second circuit are turned off, and
By demagnetizing the electromagnetic contactor MC3, the A contact MC3-a of the electromagnetic contactor MC3 is turned off, and the power to the motor 3 is cut off.

After turning off the reverse switch _S6 , the motor 3 is decelerated and stopped within the time set by the timer.

Next, press the pushbutton S ₁ for simultaneous operation of the changeover switch.
When -a is pressed and the changeover switch _S1 is turned on, the operation mode changeover relay R6 is energized, and the A contacts 6-a1 and R6-a2 of the relay R6 are turned on, and R6-b1, R6- b2 is turned off.

In this state, when hoisting switch S ₃ is pressed to turn on, the hoisting magnetic contactor in the hoisting circuit is turned on.
Since the A contact AC4-a of the MC4 is turned on, power is directly applied to the motor 5 in the electric chain block without going through the inverter 1, and the electric chain block is hoisted.

In addition, when the lowering switch _S4 is pressed and turned on with the changeover switch _S1 turned on, the A contact MC5 of the lowering magnetic contactor MC5 in the lowering circuit is turned on.
-a is turned on, power is directly applied to the motor 5 in the electric chain block without going through the inverter 1, and the electric chain block is operated for lowering.

In addition, when the changeover switch _S1 is turned on, that is, when the operation is switched to simultaneous operation, the B contact R6-b1 in the hoisting circuit and the B contact in the hoisting circuit are closed.
Contact R6-b2 is off and relay R
1, R2 is never energized and therefore,
Since the B contacts R1-b and R2-b of the relays R1 and R2 in the forward running circuit and the backward running circuit are held in the OFF state, as described above,
By turning on and off the forward switch _S5 or the reverse switch _S6 , the electric trolley can be caused to travel forward and stop, and to travel backward and stop.

_FIG . 10 shows the relationship between time and motor operating status when the electric chain block motor is hoisted and hoisted under inverter control. When turned on, the inverter's output increases gradually, and the inverter's output is generated at the end of dead time _t1 at point B. At this point B, the motor starts and the inverter's output increases (for example, to 60Hz or 50Hz). Acceleration is performed at the end of the acceleration time C.
Then, hoisting operation begins at the speed set by the speed adjustment variable resistor.

Next _, if the hoisting switch _S3 is turned off at a certain point D, and then, after a pause of several seconds t3, the hoisting switch _S4 is turned on, first the hoisting switch _S3 is turned off. The moment you turn off the motor, the motor's brake is activated and the motor's hoisting operation is stopped.
The mechanical brake of the electric chain block is activated, and then the inverter output is generated at time F when the rest time t ₃ and dead time t ₂ have ended, and at this time E the motor is started and the inverter output increases. Acceleration is performed, and the acceleration end point G
Then, lowering operation begins at the speed set by the speed adjustment variable resistor.

Next, when the lowering switch _S4 is turned off at a certain time point H, the motor brake is immediately activated to stop the lowering operation of the motor, and the mechanical brake of the electric chain block is activated.

Figure 11 shows _the relationship between time and motor operating status when _the motor of the electric trolley is operated under inverter control. Then, the output of the inverter gradually increases, and the dead time t ₁
At point B, when the inverter's output reaches about 5 Hz, the motor starts at this point B, and the inverter's output increases (for example, to 60 Hz or 50 Hz) to perform acceleration, and at point C, when the acceleration ends. ,
The vehicle starts running at the speed set by the variable resistor for speed adjustment.

Next, when the forward switch S ₅ or the reverse switch S ₆ is turned off at a certain point D, the inverter output gradually decreases from, for example, 60 Hz or 50 Hz, so the motor is decelerated, and at the point E When the inverter's output reaches about 5Hz, the motor's brake is activated and the motor stops rotating. Next, at time F when the timer set time _t3 is reached, the motor power supply circuit is cut off.

When carrying out the present invention, the mechanical brake of the electric chain block may have any structure other than that shown in the drawings. In addition, a two-stage push button operation switch is used as a changeover switch,
It may be configured such that when the second step is pressed, the lifting and lowering by the electric chain block is switched to the rated speed (direct control without using an inverter). Furthermore, the operation box 10 may be provided with a speed setting variable resistor corresponding to each motor 3, 5, and when the variable resistor is set to the highest speed, the motor may be switched to direct control. .

In addition, as the motors 3 and 5, a brake motor is not used, but a motor without a built-in brake and an electromagnetic brake independent of the motor are used, and the electromagnetic brake is controlled to operate in conjunction with the rotation of the motor. It's okay.

〔Effect of the invention〕

According to this invention, by simply switching the changeover switch _S1 , the electric trolley 2 or the electric chain block 4 can be operated via one inverter 1.
The electric trolley-equipped electric trolley can be switched between an independent operating state and a simultaneous operating state of operating the electric trolley 2 via the inverter 1 and operating the electric chain block 4 not via the inverter 1, and therefore can be operated in various states. The chain block can be manufactured at low cost, and is provided with a timer relay TR that operates when the electric trolley is decelerated by the inverter 1 to cut off the power to the motor 3 of the electric trolley 2 with a delay. It is possible to perform forced braking and then bring the vehicle to a gentle stop, thereby improving safety. Furthermore, since the speed reduction device in the electric chain block 4 is equipped with a mechanical brake to prevent the suspended load from falling, it is possible to eliminate the risk of the suspended load falling during the dead time when starting the lift during inverter control. Effects can be obtained.

[Brief explanation of drawings]

The drawings show embodiments of the invention,
Figure 1 is a front view of the electric chain block with electric trolley, Figure 2 is its side view, Figure 3 is a partially vertical side view of the electric chain block, Figure 4 is a vertical side view of the mechanical brake, and Figure 5 is a side view of the electric chain block. The figure is a longitudinal front view showing a part of the mechanical brake, Figure 6 is a front view of the operation box, Figure 7 is a diagram showing the speed control circuit of the electric chain block with electric trolley, and Figure 8 is the speed control circuit. FIG. 9 is an enlarged view of the power supply control circuit in FIG. 9, and FIG. 9 is an enlarged view of the vicinity of the inverter in the speed control circuit. Fig. 10 is a diagram showing the relationship between time and motor operating status when the electric chain block motor is operated under inverter control for hoisting and hoisting operations, and Fig. 11 is a diagram showing the relationship between time and motor operating status when the electric chain block motor is operated under inverter control. FIG. 3 is a diagram showing the relationship between time and motor operating state. In the figure, 1 is an inverter, 2 is an electric trolley, 3 is a motor, 4 is an electric chain block, and 5 is an electric trolley.
is the motor, 6 is the running rail, 7 is the frame, 1
0 is an operation box, 12 is a drive shaft, 14 is a hollow driven shaft, 15 is a road chain, 16 is a load sheave, 17 is a large diameter driven gear, 18 is an intermediate shaft, 19 is a small diameter intermediate drive gear, 20 is a small diameter drive gear , 21 is a large diameter intermediate driven gear, 22 is a brake tightening board, 23
24 is a friction plate, ₂₅ is a pawl piece, _S1 is a changeover switch for simultaneous operation and single operation, S3 is a hoisting switch, _S4 is a hoisting down switch, _S5 is a forwarding switch, S ₆ is the reverse switch, TR is the timer relay,
VR is a variable resistor for speed adjustment.

Claims (1)

[Claims] 1 One inverter 1 is provided in the power supply circuit of the electric chain block with an electric trolley, the motor 3 of the electric trolley 2 is connected to the power source via the inverter 1, and the motor 5 of the electric chain block 4 is connected to the power source through the inverter 1.
is connected to the power source via the inverter 1 and also connected to the power source not via the inverter 1, and the control circuit of the electric chain block with electric trolley includes the inverter 1 connected only to either one of the motors 3 and 5. A changeover switch for switching between a standalone operating state in which power is supplied via the inverter 1 and a simultaneous operating state in which the motor 3 of the electric trolley is energized via the inverter 1 and the motor 5 of the electric chain block 4 is energized not via the inverter 1. S ₁ and a timer relay TR that is activated when the electric trolley is decelerated by the inverter 1 and delays the power supply of the motor 3 of the electric trolley 2 to cut off the power supply to the electric chain block 4. A speed control device for an electric chain block with an electric trolley, characterized in that it is equipped with a mechanical brake for prevention.