Method and apparatus for controlling the depth of cut of a trackhoe bucket

1. An apparatus for controlling the depth of a hoe bucket, comprising:

a hoe bucket defining a cutting edge;

an elongated member operationally connected to the bucket;

an actuator operationally connected to the elongated member;

an electronic controller operationally connected to the actuator;

a position sensor operationally connected to the cutting edge and operationally connected to the electronic controller;

wherein the actuator may be energized to pivot the elongated member to a position adjacent the cutting edge for engaging ground; and

wherein positioning of the elongated member adjacent the cutting edge prevents the cutting edge from digging ground.

2. The apparatus of claim 1 wherein the elongated member is pivotably connected to the bucket.

3. The apparatus of claim 1 and further comprising a recess formed in the bucket, and wherein the actuator is substantially positioned in the recess.

4. The apparatus of claim 1 wherein the actuator further comprises a hydraulic pump; and a hydraulic cylinder connected in hydraulic communication with the hydraulic pump; wherein the hydraulic cylinder is operationally connected to the elongated member.

5. The apparatus of claim 1 wherein the actuator further comprises a pneumatic pump; and a pneumatic cylinder connected in pneumatic communication with the pneumatic pump; wherein the pneumatic cylinder is operationally connected to the elongated member.

6. The apparatus of claim 1 wherein the position sensor is a GPS transceiver.

7. The apparatus of claim 1 and further comprising a reference signal operationally connected to the microprocessor.

8. A system for automatically preventing overdigging with a mechanical shovel, comprising:

a microprocessor;

a sensor operationally connected to the microprocessor for measuring the position of a shovel bucket relative to grade;

a movable interrupt bar for blocking the shovel bucket; and

an actuator for moving the interrupt bar operationally connected to the microprocessor and to the interrupt bar;

wherein the microprocessor is programmable with predetermined desired grade parameters;

wherein the microprocessor is programmable to compare a measured bucket position to programmed grade parameters; and

wherein the microprocessor is programmable to send a signal to the actuator to move the interrupt bar between the shovel bucket and ground when the shovel bucket begins to exceed programmed grade parameters.

9. The apparatus of claim 8 wherein the interrupt bar is pivotably connected to the bucket.

10. The apparatus of claim 8 and further comprising a recess formed in the bucket, and wherein the actuator is substantially positioned in the recess.

11. The system of claim 8 wherein the sensor is a GPS transceiver.

12. The system of claim 8 wherein the interrupt bar is a generally cylindrical member pivotably connected to the shovel bucket.

13. The system of claim 8 wherein the shovel bucket is a track hoe bucket.

14. The system of claim 8 wherein the shovel bucket is a skid loader bucket.

15. A method for preventing overdigging and maintaining grade with a mechanical hoe, comprising:

a) programming an electronic controller with desired grade parameters;

b) receiving depth information regarding a hoe bucket by electronic controller;

c) calculating whether the hoe bucket is below grade;

c) sending a first signal from electronic controller to hydraulic pump when the bucket is below grade;

d) moving an interrupt bar to block the hoe bucket into response to the first signal;

e) sending a second signal from electronic controller to hydraulic pump when the bucket is above grade;

f) moving the interrupt bar to unblock the hoe bucket in response to the second signal;

wherein the interrupt bar is movably connected to the bucket.

16. The method of claim 15 wherein the position information is received by a GPS transceiver.

17. The method of claim 15 wherein the actuator assembly includes a hydraulic pump operationally connected to the electronic controller and a hydraulic cylinder operationally connected to the interrupt bar and to the hydraulic pump.