JPS5943388B2 - Crane control device - Google Patents

Description

[Detailed description of the invention] The present invention relates to a cargo handling control device for a crane.

Although this type of technology has been provided in Japanese Patent Application Laid-open No. 48-2547, the present invention provides a new function for the purpose of improving operability.

In the technique of JP-A-4-8-2547, the ascending speed of cargo handling can be controlled by the converter governor, but the descending speed is controlled by positive feedback because the input rotation of the converter governor is reversed. It has the disadvantage of not being able to control speed.

In the present invention, the above-mentioned drawbacks are solved by making the input rotation of the converter governor unidirectional regardless of whether the cargo is being lifted or lowered during cargo handling.

The present invention will now be described with reference to illustrated embodiments.

In Fig. 1, a diesel engine 1 serving as a power source has its upper and lower limits of rotation regulated by a high/low speed governor 2 (hereinafter referred to as the engine governor), and the rotation of the fuel control lever 2a responds to demands. produces an output.

The output of the engine is coupled via a torque converter 3 to a winch drum 4, which is a loading mechanism of the crane.

On the other hand, the output shaft of the torque converter transmits rotation to a second speed governor (hereinafter referred to as converter governor) 6 via a differential gear mechanism 5.

This second speed governor is composed of a fluid speed governor and is of the full speed control type, and may be of the type shown in the aforementioned Japanese Patent Application Laid-Open No. 48-2547, but may also be of the general Japanese Patent Publication No. 50-14291.

The output lever 6a is connected to the fuel control lever 2a of the engine governor 2.

The input lever 6b is connected to the control lever 8.

The differential gear mechanism 5 has an input shaft 5a and an output shaft 5b disposed on a coaxial extension, and a spur gear zl on the input and output shafts facing each other at the ends.
, z4 (the number of teeth is zl>z4) is fixed, and a gear z2 having the same number of teeth as gear Z4 is fixed to one end of a hollow shaft 5c provided parallel to the shaft, meshing with gear Z1, etc. Gear z on the end
A gear Z3 having the same number of teeth as 1 is fixed and meshed with gear Z4.

The hollow shaft has the above-mentioned arm 5 with a bearing on the output shaft.
The shaft connecting d and 5 e passes through the gear z2. I support z3.

Furthermore, a spur gear Z5 is fixed to the end of the bearing of the arm 5e and is driven by a constant rotation drive source (synchronous motor) 7.

The rotation speed of gear Z5 by the synchronous motor is determined as follows.

The input rotation of the converter governor is determined by connecting Nl, N2, and N3 to gears z1. z5. Assuming the rotation of z4, N5=(
zl, z3/z2, z4).(Nl-N2)+N2.

In order for the input rotational direction to the converter governor 6 to be the same rotational direction as when the cargo is being lowered during loading and unloading, for example, the input rotational direction to the converter governor must be at the maximum rotation when the drum shaft rotates in the opposite direction during loading and unloading. N2 is determined so that the minimum rotation (N3>O) is achieved.

That is, in the above equation, Nl<0 because of the reversal, but N3
〉To maintain 0, N2-(z 1 ・z 3/Z2・z
4) Determine the size of N2 so that (N17N2)>0.

The operation of the above configuration is performed as follows.

The rising speed of the cargo handling load is determined by the output torque of the torque converter 3, and the output torque of the torque converter is determined by the rotation speed of the engine 1.

Further, the engine speed is determined by the deviation value between the speed setting value of the aforementioned full speed control type converter governor 6 and the input value (rotation N2).

For example, if the output torque T1 of the torque converter 3 is greater than the cargo handling load torque T2, and TI>T2, the control lever 8
If, for example, the elevation angle of a boom (not shown) changes and the load on the torque converter increases while the cargo handling load is increasing at a speed based on the set value, the output rotation will decrease and the converter governor 6 will move the output lever 6a in the direction of fuel increase. This increases the engine speed and the output torque of the torque converter.

When the load decreases, the opposite effect takes place, keeping the lifting speed of the load at a constant value corresponding to the set value, regardless of load fluctuations.

Lower the set value of control lever 8 to torque converter 3.
The cargo is suspended at the engine speed when the output torque and the cargo handling load torque are TI=T2.

To determine the suspension height, move the control lever 8 in the direction of fuel reduction at the desired position of the rising cargo load.

Just return it.

If the control lever is returned further, the engine rotation will further drop, and TI<T2, and the output shaft of the torque converter 3 will rotate in the opposite direction.

However, since N3>0, the input rotation of the converter governor 60 is not reversed.

Therefore, the converter governor 6 performs a speed regulating function as negative feedback control even when the load changes while the cargo handling load is decreasing.

The differential gear mechanism is not limited to this, and may be a planetary gear mechanism or the like.

Furthermore, the converter governor is not limited to a fluid speed reducer.

As described above, according to the present invention, cargo handling operations such as raising, lowering, stopping in the air, and operations can be smoothly performed without shock by simply operating the control lever 8, without requiring brake or clutch operations as in conventional methods. It greatly contributes to improving the efficiency of cargo handling operations.

This invention can be implemented in various other forms without departing from the scope of the claims, provided that the content thereof is fully understood.

[Brief explanation of the drawing]

FIG. 1 is an overall view of a crane control device according to the present invention, and FIG. 2 is an enlarged view of its main parts. 1: Engine, 2: Engine governor, 3: Torque converter, 4: Winch drum, 5: Differential gear mechanism, 6:
Converter governor, 7: Constant rotation drive source.

Claims (1)

[Claims] 1 In a crane control device that transmits the engine output to the loading machine via a torque converter and regulates the engine rotation with a converter governor that receives the rotation of the output shaft of the torque converter as input, the output rotation is determined by two input rotations. The rotation of the output shaft of the torque converter and the rotation of the constant rotation drive source are respectively the two input rotations of the differential gear mechanism, and the output rotation drives the converter governor, and the output of the torque converter is A control device for a crane, characterized in that the rotation of a constant rotation drive source is set so that the drive rotation of a converter governor is the lowest when the shaft is at its highest rotation in the downward direction of cargo handling.