Method and apparatus for controlling angles of working machine

• US 6,246,939 B1
• Filed: 09/23/1999
• Issued: 06/12/2001
• Est. Priority Date: 09/25/1998
• Status: Expired due to Fees

• Current Assignee: Komatsu Ltd.
• Original Assignee: Komatsu Ltd.
• Inventors: Nozawa, Yasuhiko
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): Hernandez, Olga
• Application Number:
  US09/401,303
• Time in Patent Office: 628 Days
• Field of Search: 701/50, 701/36, 374/11, 340/686.1, 172/810, 172/818, 172/819
• US Class Current: 701/50
• CPC Class Codes: E02F 3/3411 of the Z-type
• CPC Class Codes: E02F 3/432 for keeping the bucket in a predetermined position or attitude
• CPC Class Codes: E02F 3/434 providing automatic sequences of movements, e.g. automatic dumping or loading, automatic return-to-dig
• CPC Class Codes: E02F 9/2041 Automatic repositioning of implements, i.e. memorising determined positions of the implement for dipper-arms or bucket-arms E02F3/434, E02F3/437, E02F3/438, E02F3/439 take precedence
• CPC Class Codes: E02F 9/2228 including an electronic controller
• CPC Class Codes: E02F 9/2282 Systems using center bypass type changeover valves
• CPC Class Codes: E02F 9/2285 Pilot-operated systems

Abstract

The invention provides a method and an apparatus for controlling angles of a working machine, which even unskilled operators can easily and efficiently perform in excavation and loading operation. For this purpose, the control apparatus includes an automatic excavation starting button (34), a boom angle detecting device (40), a bucket angle detecting device (41), an electromagnetic proportional control valve (20) for controlling the boom controlling valve (13) and the bucket controlling valve (14), and a controller (25) which starts an automatic excavation mode when inputting a start signal from the automatic excavation starting button (34), while outputting a control signal to cause the boom (3) to ascend at a predetermined speed to the electromagnetic proportional control valve (20), inputs the respective signals from the boom angle detecting device (40) and the bucket angle detecting device (41) to perform predetermined computation, and based on the previously stored automatic excavation mode, outputs a control signal to tilt the aforesaid bucket (4) at a predetermined angle in response to the ascending boom angle to the electromagnetic proportional control valve (20).

Claims

1. A method for controlling angles of a working machine of a front-end loader having a working machine including a boom (3) attached to the front portion of a vehicle body to be ascendable and descendable, and a bucket (4) attached to the front end portion of said boom (3) to be vertically rotatable, comprising the steps of:

previously storing an automatic excavation mode expressing predetermined relationship of a bucket angle to a boom angle in excavation;

during excavation, after manually setting said boom (3) and said bucket (4) at an automatic excavation starting position, starting an automatic excavation, and controlling the ascent of said boom (3) and the tilt of said bucket (4) based on the relationship between the boom angle and the bucket angle in said stored automatic excavation mode to thereby control each angle.

2. An apparatus for controlling angles of a working machine of a front-end loader including a boom (3) attached to the front portion of a vehicle body to be ascendable and descendable, a bucket (4) attached to the front end portion of said boom (3) to be vertically rotatable, a boom controlling valve (13) and a bucket controlling valve (14) respectively controlling ascending and descending movements of said boom (3) and tilting and dumping, movements of said bucket (4) based on operating signals from a boom operating lever (30) and a bucket operating lever (32), said apparatus comprising:

an automatic excavation starting button (34) for instructing the start of automatic excavation by means of said boom (3) and said bucket (4);

a boom angle detecting means (40) for detecting an ascent angle of said boom (3);

a bucket angle detecting means (41) for detecting a tilt angle of said bucket (4);

an electromagnetic proportional control valve (20) for inputting each control signal of said boom (3) and said bucket (4), and controlling said boom controlling valve (13) and said bucket controlling valve (14); and

a controller (25) which starts an automatic excavation mode when inputting a start signal from said automatic excavation starting button (34),

while outputting a control signal to cause said boom (3) to ascend at a predetermined speed to said electromagnetic proportional control valve (20),

inputs the respective signals from said boom angle detecting means (40) and said bucket angle detecting means (41) to perform predetermined computation, and based on the previously stored automatic excavation mode, outputs a control signal to tilt said bucket (4) at a predetermined angle in response to the ascending boom angle to said electromagnetic proportional control valve (20).

5. The apparatus for controlling the angles of the working machine in accordance with any one of claim 2 to claim 4, further comprising:

a kick down switch (35) for shifting the traveling speed from the forward second gear to the forward first gear.

6. The apparatus for controlling the angles of the working machine in accordance with any one of claim 2 to claim 4, further comprising:

a mode selecting means (42) which is connected to said controller (25), and allows the selection of any one of the automatic excavation modes in which at least one of the following is previously set;

the bucket tilt angle corresponding to a predetermined boom ascent angle, and the bucket tilt period of time corresponding to the predetermined boom ascent angle.

7. The apparatus for controlling the angles of the working machine in accordance with any one of claim 2 to claim 4, further comprising:

a kick down switch (35) for shifting the traveling speed from the forward second car to the forward first gear; and

a mode selecting means (42) which is connected to said controller (25), and allows the selection of any one of the automatic excavation modes in which at least one of the following is previously set;

the bucket tilt angle corresponding to a predetermined boom ascent angle, and the bucket tilt period of time corresponding to the boom ascent angle.

8. The apparatus for controlling the angles of the working machine in accordance with claim 2 or claim 3, further comprising

an engine speed detector (43) for detecting engine speed and outputting a detection signal to said controller (25)

said controller (25) selecting, the automatic excavation mode corresponding to the magnitude of a load determined based on said engine speed detection signal out of said stored automatic excavation modes, and controlling the movement of said bucket (4) based on said selected excavation mode.

3. An apparatus for controlling angles of a working machine of a front-end loader including a boom (3) attached to the front portion of a vehicle body to be ascendable and descendable, a bucket (4) attached to the front end portion of said boom (3) to be vertically rotatable, a boom controlling valve (13) and a bucket controlling valve (14) respectively controlling ascending and descending movements of said boom (3) and tilting and dumping movements of said bucket (4) based on operating signals from a boom operating lever (30) and a bucket operating lever (32), said apparatus comprising:

an automatic excavation starting button (34) for instructing the start of automatic excavation by means of said boom (3) and said bucket (4);

a boom angle detecting means (40) for detecting an ascent angle of said boom (3);

a bucket angle detecting means (41) for detecting a tilt angle of said bucket (4);

an electromagnetic proportional control valve (20) for inputting each control signal of said boom (3) and said bucket (4), and controlling said boom controlling valve (13) and said bucket controlling valve (14); and

a controller (25) which starts an automatic excavation mode when inputting a start signal from said automatic excavation starting button (34),

while outputting a control signal to cause said boom (3) to ascend in accordance with the signal from said boom operating lever (30) to said electromagnetic proportional control valve (20),

inputs the respective signals from said boom angle detecting means (40) and said bucket angle detecting means (41) to perform predetermined computation, and based on the previously stored automatic excavation mode, outputs a control signal to tilt said bucket (4) at a predetermined angle in response to the ascending, boom angle to said electromagnetic proportional control valve (20).

4. An apparatus for controlling angles of a working machine of a front-end loader including a boom (3) attached to the front portion of a vehicle body to be ascendable and descendable, a bucket (4) attached to the front end portion of said boom (3) to be vertically rotatable, a boom controlling valve (13) and a bucket controlling valve (14) respectively controlling ascending and descending movements of said boom (3) and tilting and dumping movements of said bucket (4) based on operating signals from a boom operating lever (30) and a bucket operating lever (32), said apparatus comprising:

an automatic excavation starting button (34) for instructing the start of automatic excavation by means of said boom (3) and said bucket (4);

a boom angle detecting, means (40) for detecting an ascent angle of said boom (3);

an electromagnetic proportional control valve (20) for inputting each control signal of said boom (3) and said bucket (4), and controlling said boom controlling valve (13) and said bucket controlling valve (14); and

a controller (25) which starts an automatic excavation mode when inputting a start signal from said automatic excavation starting button (34),

while outputting a control signal to cause said boom (3) to ascend in accordance with the signal from said boom operating lever (30) to said electromagnetic proportional control valve (20),

inputs the signal from said boom angle detecting means (40) to perform predetermined computation, and based on the previously stored automatic excavation mode, outputs a control signal to tilt said bucket (4) for a predetermined period of time in response to the ascending boom angle to said electromagnetic proportional control valve (20).