×

Automatic control of backhoe digging depth

  • US 4,129,224 A
  • Filed: 09/15/1977
  • Issued: 12/12/1978
  • Est. Priority Date: 09/15/1977
  • Status: Expired due to Term
First Claim
Patent Images

1. The method of operating a backhoe to move the digging edge of the bucket thereof along a path parallel to the desired slope of the bottom of the excavation and with the digging angle of the bucket being substantially constant with respect to said desired slope, said backhoe having an outreach boom vertically pivotal about a horizontal axis defining an Angle A with respect to the horizontal, a downreach boom pivotally secured to the free end of the outreach boom to define an Angle B therebetween, and a digging bucket pivotally secured to the other end of the downreach boom to define Angle C between the digging edge of the bucket and its pivotal axis on the downreach boom, there being three power-actuating means respectively operating on said outreach boom, said downreach boom, and said digging bucket to vary said Angles A, B and C, comprising the steps of:

  • (1) manually controlling the power-actuating means determining Angle B to move said bucket through a digging stroke;

    (2) generating a first electrical signal continuously proportional to Angle B;

    (3) controlling one of the two remaining power-actuating means as a trigonometric function of Angle B, the length of the outreach boom, and the length of the downreach boom, thereby determining either Angle A or Angle C;

    (4) generating a second electrical signal continuously proportional to the Angle determined by step (3); and

    (5) controlling the remaining power-actuating means as a linear function of the sum of the electrical signals generated in steps (2) and (4).

View all claims
  • 5 Assignments
Timeline View
Assignment View
    ×
    ×