JPS5912598B2 - Traveling crane skew control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a traveling lane equipped with a plurality of traveling electric motors, and more particularly to a skew control device for a traveling lane that controls the skewing force of a crane due to an unbalanced load.

In general, for large lanes, especially those with long spans, a multi-motor running system in which each wheel is driven by a plurality of motors is widely used.

Conventionally, in this type of crane traveling system, if the crane structure is a trolley or a crane that moves laterally, an unbalanced load is generated depending on the position of the trolley, and a difference is created in the load applied to each wheel on both sides, resulting in a skew force. occurs.

Furthermore, this type of lane is often installed on a quay with strong winds, and the wind load from the lateral direction is also added, which tends to further increase this diagonal force.

For this reason, the rail on the heavy load side comes into strong contact with the flange of the wheel, resulting in increased running resistance and wear, and the wheel on the small load side is subjected to more torque than necessary, causing it to spin. As a result, the crane cannot run smoothly.

The present invention has been made in consideration of the above points, and is designed to switch the speed-torque characteristics of each electric motor according to the position of the trolley and the magnitude of the wind load in a lane where a lateral moving trolley is running using a multi-motor running system. The present invention provides a skew control device for a lane in which the vehicle is traveling, which suppresses skew force.

Hereinafter, one embodiment of the present invention will be described in detail with reference to the accompanying drawings.

In FIG. 1, a running lane 1 runs on a rail 6 using four wheels 2 to 5, and each wheel 2 to 5 is provided with a drive mechanism (directly connected electric motor and reduction gear) 7 to 10, respectively. ing.

A trolley 15 that moves laterally on four wheels 11 to 14 is provided on the lane 1 in which the vehicle runs, and this trolley 15 is driven by a drive mechanism 16 thereof.

Further, limit switches ILS and 2LS for detecting the position of the trolley 15 are provided on the traversing path 17 of the trolley 15, and these position detection switches ILS are set to open when the trolley 15 is in range a, and when it is in ranges b and C. The same position detection switch 2LS is open when it is in the C range, a,
It is configured to be closed when it is in range b.

Although not shown, a wind speed switch is provided on the lane 1 in which the vehicle runs, which closes when the wind speed from the side exceeds a certain level.

Fig. 2 shows each motor of each drive mechanism 7 to 10 shown in Fig. 1 (the case is shown when a three-phase wound induction motor is used).
This figure shows the torque control circuits of IIM to 4IM, and is configured to control the motor circuit a by the control circuit.

In other words, motor circuit a has one of each motor IIM to 4IM.
A reversible electromagnetic contactor 18 is provided on the next side, and on the secondary side thereof, resistors 19 to 22 are provided, and electromagnetic contactors 23 to 26 that short-circuit a part of each of the resistors 19 to 22 when turned on.
and is configured to control the excitation state of the energizing coils 1A to 4A of each of these electromagnetic contactors 23 to 26 according to the open/closed states of the position detection switches ILS, 2LS and the wind speed switch WI. There is.

In this case, in the running lane 1 as shown in FIG. It is thought that the shaft is mechanically connected to the motor IIM on one side by the frictional force between the motor IIM and the motor 2.
It is considered that the IM load or the 3IM and 4IM loads each always have the same characteristics.

Therefore, as shown in Figure 2, the energizing coils 1A and 2A, 3A and 4A of the electromagnetic contactor corresponding to the motor on each side are
are configured to be energized simultaneously by the same detection signal (closing operation of the position detection switch LS or the wind speed switch WI).

The operation of the lane skew control device according to the present invention configured as described above will be explained below.
Let us consider the crane traveling when the crane 5 is at the right end of lane 1, that is, within range C.

At this time, the load applied to the wheels 2 and 3 becomes larger than that applied to the wheels 4 and 5, producing a diagonal force, but in order to cope with this diagonal force, the driving force of the wheels 2 and 3 is transferred to the wheel 4. ，
It needs to be larger than that of 5.

Assuming that the wind from the side is below the operation of the wind speed switch WI, in FIG.
LS is closed, and position detection switch 2LS and wind speed switch WI are each opened.

Only the previously energized coils IA and 2A are energized and the electromagnetic contactors 23 and 24 are turned on, thereby shorting out a portion of the secondary resistors 19 and 20.

At this time, the electromagnetic contactors 25 and 26 are in an open state, so
The generated torques of the electric motors IIM and 2IM have the torque characteristic shown in FIG. 3, which is larger than the generated torque of the electric motors 3IM and 4IM (torque characteristic shown in the same figure).

If the reversible electromagnetic contactor 18 is turned on in this state, the running lane 1 will be efficiently accelerated by the driving torque proportional to the load applied to the wheels 2, 3 and 4, 5 on both sides. .

Furthermore, when the trolley 15 is in the range shown in FIG.
As shown in the figure, the vehicle accelerates by sharing the load equally among the wheels 2 to 5.

Further, when the trolley 15 is in the a range, the position detection switch 2LS is closed and the position detection switch IL is closed, contrary to the above.
S is opened, and as a result, the electric motors IIM and 2IM are operated according to the torque characteristic of (2), and the electric motors 3IM and 4IM are operated according to the torque characteristic of I.

Furthermore, when the crosswind blowing from a to C direction (the same is true even when blowing from C to a direction) exceeds a certain wind speed, the wind speed switch WI closes, and the position of the trolley 15 is changed. Regardless of the auxiliary coil 1A to 4A
is excited.

Therefore, all the corresponding electromagnetic contactors 23 to 26 are turned on, and the electric motors IIM to 4IM are operated according to the torque characteristic of I.

In other words, when a crosswind blows at a speed higher than the wind speed that causes the wind speed switch WI to close, the wind load becomes dominant as the load applied to each wheel 2 to 5 in lane 1, and this wind load is and each electric motor IIM~4
The IM will be operated according to the preset larger torque characteristic.

As described above, the lane skew control device according to the present invention suppresses the skew force by changing the drive torque of each wheel 2 to 5 according to the position of the trolley 15 and the magnitude of the wind load. Figure 4 shows the stress characteristics due to the oblique force with respect to the trolley position at this time.

If no measures are taken against the skew force as in the past, that is, if all electric motors IIM to 4IM are operated with the same torque characteristics, the skew force as shown by the dotted line in the figure Stress is generated, and the maximum stress is σa, which exceeds the flange friction limit of the wheel and causes flange friction on the left side.

On the other hand, in the case of the skew control device according to the present invention, as shown by the solid line in the figure, the stress due to the skew force is switched within the flange friction limit according to the trolley position, so flange friction does not occur in any case. .

Note that the flange friction limit takes into account wind window force from the lateral direction, so it has asymmetrical characteristics as shown in the figure.

As described above, the skew control device for a running lane according to the present invention reduces the skew force generated by the unbalanced load caused by the lateral movement of the trolley and the crosswind, and thereby prevents flange friction and facilitates maintenance and inspection. In addition, it has various advantages such as no need for unnecessary driving force, resulting in excellent running performance and stability, and excellent acceleration performance since the wheels are prevented from slipping.

The lane skew control device according to the present invention has been described as one that switches the torque of each electric motor depending on the position of the trolley and the magnitude of the wind load. It goes without saying that various arbitrary modifications can be easily made, such as switching the torque characteristics by combining conditions such as load position and wind load.

A brief description of the drawing.

FIG. 1 is a top view showing lanes traveled according to an embodiment of the present invention, FIG. 2 is an electrical connection diagram showing a torque switching circuit for multiple electric motors in the same embodiment, and FIG. 3 is a diagram showing the speed at which the motors are switched. FIG. 4 is a characteristic diagram showing the torque characteristics, and is a characteristic diagram of the stress due to the diagonal force of the running lane controlled by the same embodiment.

1...Running lane, 2-5...Wheels, 6...Rail, 7-10...Drive mechanism, 15... Trolley, 16...To01
J drive mechanism, 18...Reversible electromagnetic contactor, 19
~22...Secondary resistor, 23-26...
・Magnetic contactor, ILS, 2LS...Position detection switch, W■...Wind speed switch, 1A to 4A
・・・・・・Magnetic contactor energizing coil, L・・・・・・
Flange friction limit.

Claims (1)

[Scope of Claims] 1. In a lane in which a plurality of traveling electric motors each having a lateral moving trolley and having drive mechanisms on the left and right sides run, whether the lateral moving trolley is located on either the left or right side in the lateral direction. There are left and right position detectors that detect the wind speed, a wind speed detector that detects when the wind speed from the side exceeds a certain level, and a part of the secondary resistor of each motor that is short-circuited when the motor is turned on to reduce the torque. Equipped with an electromagnetic contactor that applies weight, when the trolley is on the right side, it applies torque to the traveling electric motor of the right drive mechanism, and when the trolley is on the left side, it applies torque to one traveling electric motor of the left drive mechanism. In addition, when the wind speed from the side exceeds a certain level, torque is applied to the traveling electric motors of the right and left drive mechanisms to switch the torque characteristics of each traveling electric motor. Skew control device.