JPH01187195A - Shift allowance length display device in construction machinery - Google Patents

Abstract

PURPOSE:To develop the machine faculty to the max. limit without depending onto feeling by selecting a calculation equation which represents each shift limit of joint shafts and calculating and displaying the allowance length of shift in the vertical direction by using the above-described calculation equation from the coordinate values of the joint shafts at present. CONSTITUTION:The variation of the axis angle accompanied with operation is detected by each potentiometer 12a-12c installed onto the joint parts of the joint shafts 11a-11c. The data is converted to the digital value by an A/D converter 13b and continuously inputted into a calculation device 14. While, also the instructed process No. data and instructed timing signal are inputted into the calculation device 14 from an instruction panel 15. In a memory device 16, the machine constants, arithmetic equation which represents the shift limit point, coordinate data for singular points, process No. accompanied with the vertical shift operation, and the shift direction data in this process are previously memorized, and inputted into the calculation device 14. Then, the allowance length in the vertical shift is calculated from each input value, and displayed on a display device 17. Therefore, the machine faculty can be developed to the max. limit.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a movement margin display device for a construction machine having vertical motion.

[Prior Art] Generally, some construction machines such as cranes used at construction sites have multiple joints and perform vertical movement for transporting building materials and the like. When such construction machinery is used to transport building materials, the operator estimates the operating margin of the crane based on his/her experience. For this reason, for example, if the target point is close to the operating limit position,
If the visual estimation was incorrect, extra work was required.

[Problems to be Solved by the Invention] As described above, in the past, the operating margin of a construction machine was estimated based on the operator's intuition, and thus the machine could not be used effectively to the limit of its capacity. In addition, when requesting an operation close to the limit, the machine moves to teach the target point after teaching the starting point, but if the machine reaches the limit position before reaching the target point (,; This method has the disadvantage that it has very poor operability because it requires repeated movement to teach the target point by changing the target point.

The present invention has been made in view of the above-mentioned points, and an object of the present invention is to provide a construction machine margin travel length display device that allows the operator to easily know the travel margin of the construction machine without relying on the operator's intuition. shall be.

[Means and effects for solving the problem] The present invention stores a teaching process involving a vertical movement operation and the direction of this movement in advance, and when executing the teaching operation, a position corresponding to the starting point of the vertical movement process is stored. When a teaching command signal is input, the vertical movement allowance length in the movement direction from this starting point is calculated and displayed on the display device.

[Example] Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a travel margin display device for construction machinery according to an embodiment of the present invention, and FIG. 2 is a diagram showing the structure of a general lane used in the embodiment. . Here, a crane consisting of three joint shafts and no hanging wire is used.

In FIG. 1, 1la-11c are joint shafts of the crane, and 12a-12c are potentiometers attached to the joints of each of the joint shafts 11a-11c for detecting the rotation angle of the shafts. Reference numeral 13 denotes an A/D converter with a multiplexer that converts an analog signal having information on the rotation angle detected by the potentiometers 1ja to 12c into a digital signal.

14 is an arithmetic device having a CPU, and has a teaching process number,
In response to commands from the teaching command panel 15 that inputs teaching timing signals, data processing from the A/D converter 13 is performed using a storage device IB that stores mechanical constants, arithmetic expressions representing movement limit points, etc. Let's do it.

Reference numeral 17 denotes a display device that displays the movement margin, which is the processing result.

The joint shaft 11
Changes in the axial angles (indicated by θ, α, β) accompanying the movement of a-11c are detected. This data is converted from an analog value to a digital value by passing it through an A/D converter with a multiplexer 13, and is continuously input to the arithmetic unit 14.

On the other hand, data indicating a teaching process number and a teaching timing signal are inputted to the arithmetic unit 14 from the teaching command panel 15 .

In addition to the execution program, the storage device 1B also contains mechanical constants (joint axis length, maximum and minimum values of axis angle), arithmetic expressions representing movement limit points, coordinate data of singular points that serve as judgment criteria, and vertical movement. The process number accompanying the operation, the movement direction data of this process, etc. are stored in advance.

The display device 17 is for displaying the vertical movement margin obtained as a calculation result, and includes a 7-segment display,
A CRT display or the like is used.

The operation of the construction machine travel margin display device constructed in this way will be explained with reference to FIG. 3.

The joint shaft 11c has a chuck, and is controlled so that it is always vertical because it is necessary to maintain a constant posture of the hanging building material.

As shown in FIG. 3, the motion range of each joint axis 11a to llc is the first quadrant of a Cartesian coordinate system in which the motion range of joint axis 11a is θ and the origin is the joint center O of joint axis 11a; It is assumed to be within the fourth quadrant. Also, its polarity is 0 when horizontal and 1st when it is horizontal.
The quadrant time is negative and the fourth quadrant time is positive, within ±π/2. The motion range of the joint axis 11b is α, and the effective range is within +π in the clockwise direction with 0 being on the extension line of the joint axis 11g. Further, the motion range of the joint shaft 11c is β, and the effective range is the range in which the joint shaft 11c can be vertically controlled within the entire range of motion. Furthermore, the movable ranges of each of the joint axes 11a to 11c are all within the first quadrant.

Next, the position of the chuck center point Pc in the vertical plane shown in FIG. If the coordinate in the direction is represented by x1 and the coordinate in the vertical direction is represented by 2, it can be obtained by the following formula.

x-7α and θ0mα (θ+α)
...... (1) 2--nosinθ-msin (
θ+a) +n −・= (2) However, J! : Axial length m of the joint axis 11a: Axial length n of the joint axis flb: Length of the joint axis 11c from the joint center to the chuck center Pc.Therefore, the range of motion is determined by the two variables θ and α shown in Fig. 3. The arithmetic expression f1 * ' 2 * f 3 * represents the four movement limits obtained from the combination of the minimum and maximum values of
This is the diagonally shaded range surrounded by f4.

Also, arithmetic expression f3. The coordinates of the position where the X coordinate obtained by f4 is the maximum are A (Xl, Zl), B (X2
, Z2 ), a (x2.zl), b (x2.z
2), and if the movable range is divided by a vertical line passing through each X position, the entire movable range can be divided into seven regions 81 to S7. From this, it is possible to clearly select the arithmetic expression (fx to f, s) that indicates the vertical movable limit in each region.

Here, the starting point of the vertical movement operation step is taught by the teaching command, and if the coordinates of the position at this time are (Xo, Zo), the movement margin is displayed according to the following procedure.

First, the direction of movement is distinguished whether the vertical movement direction is upward or downward. Next, it is determined in which of the regions 81 to S7 the coordinate (X o rzO) is included. Once the area containing the coordinates (x(1, z□) is determined, x□
By substituting the above equation (1), two two-coordinates can be obtained as a solution to the quadratic equation. Then, one value is selected using information on which one of the two coordinates should be selected in advance, and this value is designated as zl. These two no and z.

The travel allowance length is calculated from the difference between the two and outputted to the display device 17.

A flowchart embodying the above procedure is shown in FIG.

In this way, the joint shaft 11a=l constituting the above-mentioned crane
By selecting an arithmetic expression that expresses the movement limit of the lc, and using the above arithmetic expression from the current joint axis coordinate values to calculate and display the vertical movement margin, the operator can be accurate without relying on his or her senses. This makes it possible to know the travel margin.

In addition, in the above embodiment, three joint axes and three potentiometers are used to configure the crane, but cranes with other configurations may also use an arithmetic formula indicating the range of movement, depending on the number of axes used. It is possible to calculate the coordinates of the intersection point and the maximum horizontal position.

From this, by performing the same determination process as in the above embodiment, the margin distances to the upper and lower limit points can be calculated and displayed.

It is also possible to use encoders instead of potentiometers attached to the joints of the crane.

[Effects of the Invention] As described above, according to the present invention, it is possible to calculate and display the vertical movement margin from the current position coordinates using an arithmetic formula indicating the limit of the movement range of the construction machine. It is possible to eliminate the poor workability that relies on the operator's intuition, make the most of the machine's capabilities, shorten the working time, and improve the operating rate.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a travel margin display device for construction machinery according to an embodiment of the present invention, FIG. 2 is a diagram showing a structural model of a general lane applied to the embodiment, and FIG. FIG. 3 is a diagram showing the movable range of the crane, and FIG. 4 is a flowchart of arithmetic processing for determining the travel margin. 11a-Hc--joint axis, 12a-120"potentiometer, 13...A/D converter, 14...
Arithmetic device, 15...Teaching command panel, 16...Storage device, 17...Display device. Applicant's agent Patent attorney Takehiko Suzue

Claims (1)

[Claims] In a multi-joint construction machine that has a teaching function and has vertical movement control during the movement process, when the starting point in the vertical movement process is taught, the difference between this starting point and the vertical position coordinates limited by the mechanism. 1. A movement allowance length display device for a construction machine, comprising: a movement allowance length calculation means for determining a movement allowance length; and a means for displaying the movement allowance length obtained by the movement allowance length calculation means.