JPH0527882B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a control lever in a working machine such as a crane, which converts the amount of lever operation into an electrical signal to control the machine.

Prior Art An example of a conventional control lever is shown in FIGS. 3 and 4. The lever 1 is rotatably supported by a frame 2, and the rotation axis of the lever 1 has a rotation amount of the lever 1. A potentiometer 3 that converts the signal into an electric signal, and a return spring 4 that biases the lever 1 in the direction of returning to the neutral position are provided.

The mechanical daytent used for these control levers is as shown in Figure 6.
A plate 5 is attached to the rotating shaft of the detent, and a groove is formed in the plate 5 at a position corresponding to the detent angle. Furthermore, it is comprised of a hard ball 6 which is fitted into the groove of the plate 5 by the biasing force of a spring 7 supported by the frame 2 and stops the rotation of the plate 5.

Problems to be Solved by this Invention The relationship between the operating angle and operating force of the conventional control lever is shown by the solid line in Fig. 5 (the broken line is for returning). Therefore, as the amount of operation increases, the reaction force increases, making the lever heavy and difficult to operate.If the spring is weakened, the reaction force becomes too light near neutral, making it difficult to operate.

Further, FIG. 7 shows an example of the lever return force near the day tent. Here, when the lever is tilted to the right from the neutral position, the lever return force increases as the lever tilts, as shown by the solid line. When entering the detent area, the hard ball 6 biased by the spring is forced to move toward the bottom of the groove, causing the lever return force to rapidly decrease, sometimes reaching a negative value and reaching the bottom of the groove as if being sucked in against the operator's will. It settles down to. As the lever is further pushed down, the lever return force increases rapidly as the hard ball goes over the groove, and as soon as it crosses the groove, the return force decreases rapidly and returns to normal force. As described above, since the return force changes drastically near the day tent, it is difficult to perform fine operation in this area, and even when returning the lever to the neutral position, the same problem occurs as shown by the broken line.

Furthermore, since it is a mechanical type, the self-holding position of the day tent is predetermined and cannot be stopped at an arbitrary position, which has the disadvantage that it takes up mechanical space and cannot be made compact.

Therefore, the present invention improves the disadvantages of the conventional control lever as described above, improves operability by hardly increasing the operating force even if the operating angle of the lever increases, and improves operability within the lever operating range. It is an object of the present invention to provide a control lever which has a self-holding area (detent area) and eliminates discontinuity of operation reaction force there.

Another object of the present invention is to provide a self-returning control lever that allows the lever to be self-retained at any position within the lever operation range, making the whole compact, and easily returning to the neutral position. be.

Structure of the Invention The control lever according to the present invention includes a potentiometer and a motor attached to the rotating shaft of the lever, and a switch provided on the lever and a potentiometer output value at the time the switch is operated. and a comparator that compares the value in the memory with the value of the potentiometer, the detent position can be set in the memory by operating the switch, and the switch is operated again. or if the lever is operated beyond a preset tolerance, the detent position set in the memory is canceled and the motor is controlled to return the lever to the neutral position.

Embodiments The embodiments shown in the drawings will be explained below. As shown in Fig. 1, a lever 1 is attached to a frame 2 so as to be rotatable about a rotation axis.
A potentiometer 3 is attached to one end of the rotating shaft, and a motor 8 is attached to the other end.

Further, a switch 9 for setting the daytent position is attached to the upper end of the lever 1.

A potentiometer 3 attached to the rotating shaft of the lever 1 converts the rotation amount, which is the operating angle of the lever 1, into an electric signal, and a motor 8 generates a reaction force to return the lever 1 to the neutral position and self-holding at the day tent position. It is a torque motor that applies force.

These potentiometer 3, motor 8 and switch 9 are connected to a control block as shown in FIG.

In this control block, the potentiometer 3 is connected to a comparator 10, and the comparator 10 is connected to a memory 13 for mutually inputting and outputting data. Therefore, an electrical signal indicating the amount of rotation of the lever 1 is input to the comparator 10 and the memory 13.

In addition, a switch 9 is connected to the memory 13, and as will be explained in detail in the operation section below, if the switch 9 is turned on while the lever 1 is being operated, the output value of the potentiometer 3 at that point will be changed. Stored as detent position.

Further, when the switch 9 is turned on while the lever 1 is held at the detent position thus set, the detent position stored in the memory 13 is cleared.

When a memory value indicating the detent setting position is stored in the memory device 13, the comparator 10 compares this memory value with the output value of the potentiometer 3 and self-maintains the lever rotation angle at the memorized value. Outputs a position control signal to This position control signal is output to the position control section 11 connected to the output side of the comparator 10, and the position control section 11 torque-controls the motor 8 so as to self-hold the lever 1 position.

Furthermore, if the detent position set value is not stored in the memory 13, the comparator 10 always selects the lever 1.
A reaction force control signal according to the output value of the potentiometer 3 is output so as to return the potentiometer to the neutral position. This reaction force control signal is input to the reaction force control section 12, which controls the torque of the motor 8 so as to return the lever 1 to the neutral position.

Here, the detent setting value stored in the memory device 13 is determined once the detent is stored and the lever 1 is
Switch 9 is turned on again while it is self-holding.
Cleared when turned ON.

Further, in the self-holding state due to the detent setting, the value of the potentiometer 3 compared in the comparator 10 is a tolerance value of the stored value (for example, the stored value ±1
%), the stored value is cleared in the same way as in the previous case.

The configuration of this embodiment is as described above, and the operation will be explained based on the flowchart of FIG.

When the power is turned on, first, in step a, the stored value in the memory 13 is cleared, and in step b, the state of the switch 9 is checked. Here, switch 9
If it is in the OFF state, proceed to step 1, and return the lever 1 to the neutral position at step j or k depending on the direction in which the lever 1 is tilted.

If the switch 9 is turned on in step b, the process proceeds to step c, and the value of the potentiometer 3 indicating the angle of one rotation of the lever at that time is read into the memory and stored. Next, in step d, it is checked whether the lever 1 is within a permissible range centered on this memorized value, and if it exceeds the permissible range, the process returns to step a and the memorized value in the memory 13 is erased. step d
Repeat the process up to.

As a result, in order to return the lever 1, which has been held at an intermediate detent position, to the neutral position, the lever 1 is returned to the neutral position by applying an appropriate external force to the lever 1 and moving the lever 1 by more than the allowable width. For this reason,
Unlike conventional control levers, when there are two or more day tents, there is no problem of the day tent getting caught in the next day tent and not returning to neutral, and unlike levers without self-returning force, there is no need to manually return to the neutral position, making it easy to operate. will improve.

Further, when the lever 1 is within the allowable width in step d, the motor 8 is controlled in steps e, f, and g to hold the lever 1 at the position stored as the detent setting value. This allows the lever 1 to be held at any position for full operation.

In step d mentioned above, even while self-holding in the day tent, it is checked whether the external force applied to lever 1 has deviated from the allowable range or not, and in step h, the state of switch 9 is checked, and if it is turned ON again, the process returns to step a. Erase the memory value, cancel self-holding, and return to the neutral position.

Therefore, there is no discontinuity when the detent part comes out of self-retention, and fine operation is possible.

Effects of the Invention The embodiment of the control lever according to the present invention is as described above, and can bring about the following effects.

Even if the operating angle of the lever increases, the operating force (reaction force) hardly increases, and while the lever has a self-holding area (detent area) within the lever operating range, there is no discontinuity in the operating force, improving operability. Becomes good.

Furthermore, the lever can be self-held at any position within the lever operation range, making the whole compact, and the control lever is a self-returning type that can be easily returned to the neutral position.

[Brief explanation of the drawing]

Figure 1 is a partially cutaway front view of the embodiment, Figure 2 is a control block diagram of Figure 1, Figures 3 and 4 are configuration diagrams of the conventional example, and Figure 5 is the operating angle and operation of the conventional example. FIG. 6 is a diagram showing a configuration example of a conventional detent, FIG. 7 is a diagram showing return force characteristics in a conventional detent portion, and FIG. 8 is an operation flowchart of an embodiment. 1... Lever, 2... Frame, 3... Potentiometer, 4... Return spring, 5... Plate,
6... Hard ball, 7... Spring, 8... Motor, 9...
Switch, 10... Comparator, 11... Position control section, 12... Reaction force control section, 13... Memory device.

Claims (1)

[Scope of Claims] 1. A control lever having a lever that self-returns to a neutral position, which is attached to the rotating shaft of the lever and converts a rotation angle corresponding to the amount of operation of the lever into an electrical signal and outputs the signal. a potentiometer; a motor attached to the rotating shaft of the lever to maintain the operating position of the lever and control reaction force to the lever's neutral position; and a motor attached to the lever to move the lever to any operating position. a switch capable of setting the daytent setting position by inputting the potentiometer output value at that time when the switch is turned ON while the lever is being operated; The switch is
a memory device that clears the set position when turned on; and a memory device that inputs the output of the potentiometer and compares it with a stored value of the detent set position in the memory device, and sends a reaction force signal to the motor to maintain the operation position or a comparator that outputs an output to a motor, the comparator outputs a position hold signal to maintain the lever operation position if the potentiometer output is within a preset tolerance with respect to the stored value; The control lever is configured to clear the detent set value in the memory and output a reaction force signal so that the lever returns to a neutral position if the detent setting value is outside the allowable deviation.