1. A concrete agitating drum driving device comprising:
a hydraulic motor connected to a concrete agitating drum;
a variable capacity hydraulic pump which drives the hydraulic motor by supplying pressurized oil thereto;
a hydraulic actuator which regulates a discharge flow rate of the pressurized oil discharged from the hydraulic pump in response to an actuator driving pressure;
a load sensing valve which generates the actuator driving pressure by reducing a discharge pressure of the pressurized oil discharged from the hydraulic pump in response to a differential pressure between the discharge pressure and a load pressure acting on the hydraulic motor;
a shut-off valve which shuts off supply of the pressurized oil discharged from the hydraulic pump to the hydraulic motor; and
an unload valve which drains the pressurized oil discharged from the hydraulic pump when the differential pressure between the discharge pressure and the load pressure increases beyond a predetermined differential pressure.
2. The concrete agitating drum driving device as defined in claim 1, wherein the unload valve comprises a valve spool which selectively applies a loading section which does not drain the pressurized oil discharged from the hydraulic pump, and an unloading section which drains the pressurized oil discharged from the hydraulic pump, a spring which biases the valve spool in a direction for applying the loading section, a first pilot pressure passage which applies the discharge pressure to the valve spool as a pilot pressure biasing the valve spool in a direction for applying the loading section, and a second pilot pressure passage which applies the load pressure to the valve spool as a pilot pressure biasing the valve spool in a direction for applying the unload section.
3. The concrete agitating drum driving device as defined in claim 1, wherein the load sensing valve is configured to supply the discharge pressure to the hydraulic actuator without reducing the discharge pressure when the differential pressure increases beyond a second predetermined differential pressure which is set smaller than the first predetermined differential pressure.
4. The concrete agitating drum driving device as defined in claim 1, wherein the first predetermined differential pressure is set within a range of 0.1-1.0 megapascals.
5. The concrete agitating drum driving device as defined in claim 1, wherein the load sensing valve comprises a valve spool which applies a low-pressure section, which releases the actuator driving pressure to the reservoir, and a high-pressure section, which supplies the hydraulic actuator with the discharge pressure as the actuator driving pressure, in a proportion depending on the differential pressure, a spring which biases the valve spool in a direction for applying the low-pressure section, a first pilot pressure passage which applies the load pressure as a pilot pressure to the valve spool in the same direction as a biasing force of the spring, and a second pilot pressure passage which applies the discharge pressure as a pilot pressure to the valve spool in a reverse direction to the biasing force of the spring.
6. The concrete agitating drum driving device as defined in claim 1, further comprising a closed circuit including a first hydraulic passage and a second hydraulic passage connecting the hydraulic motor to the hydraulic pump, and a high-pressure selector valve which extracts the higher of a hydraulic pressure in the first hydraulic passage and a hydraulic pressure in the second hydraulic passage as the load pressure.
7. The concrete agitating drum driving device as defined in claim 6, wherein the hydraulic pump comprises a suction passage and a discharge passage, the shut-off valve is constituted by a connection switch-over valve which selectively applies a discharge section which connects the discharge passage to the second hydraulic passage and connects the suction passage to the first hydraulic passage, an agitating section which connects the discharge passage to the first hydraulic passage and connects the suction passage to the second hydraulic passage, and an operation-stop section which shuts off the discharge passage and the suction passage from the first hydraulic passage and the second hydraulic passage.
8. The concrete agitating drum driving device as defined in claim 7, wherein the hydraulic pump comprises a swash plate which varies the discharge flow rate according to a swash-plate angle, and a spring which supports the swash plate in a direction for increasing the swash-plate angle, and the hydraulic actuator pushes the swash plate using the actuator driving pressure in a direction to reduce the swash-plate angle against the spring.
9. The concrete agitating drum driving device as defined in claim 7, wherein the connection switch-over valve, the unload valve, the load sensing valve, the high-pressure selector valve, and the hydraulic pump are integrated into a unit.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
We claim:
1. A method for determining a planned path for a vehicle, the method comprising:
defining a border of a designated area within a work area;
determining a designated axis of the designated area;
aligning a series of generally parallel rows consistent with a travel axis having a known alignment with respect to the designated axis;
defining one of the generally parallel rows as a starting row and pointing the vehicle in a starting direction along or generally parallel to the travel axis; and
establishing a turn path segment after an end of the starting row to move the vehicle at least somewhat perpendicular to the travel axis between the starting row and a next row, a turn path segment having a turn radius greater than or equal to a minimum turning radius of the vehicle, wherein the starting row and the next row are spatially separated by a multiple of effective implement widths, less an overlap allowance; and
defining the turn path segment so as to skip one or more intervening parallel rows between the starting row and the next row.
2. The method according to claim 1 further comprising:
establishing an additional turn path segment after an end of the next row to move the vehicle at least somewhat perpendicular to the travel axis between the next row and a subsequent next row, the additional turn path segment having a turn radius greater than or equal to a minimum turning radius of the vehicle; and
defining the turn path segment so as to skip one or more intervening parallel rows between the next row and the subsequent next row.
3. The method according to claim 1 further comprising:
skipping one or more intervening rows between each last row and each next successive row of the generally parallel rows for traversal by the vehicle as the vehicle progresses through the planned path from one end of the designated area to an opposite end, each said last row and each said successive row separated by one or more effective implement widths, less an overlap allowance.
4. The method according to claim 1 further comprising:
bypassing one or more previously traversed intervening rows between a last row and a next successive row for traversal by the vehicle as the vehicle progresses through the planned path from one end of the designated area to an opposite end; and the last row and the next successive row separated by one or more effective implement widths, less an overlap allowance.
5. The method according to claim 1 further comprising:
heading the vehicle in opposite directions for adjacent rows of the generally parallel rows, each of the generally parallel rows having an effective implement width and an offset from an adjacent row by an overlap allowance.
6. The method according to claim 1 wherein the overlap allowance between any two adjacent rows of the planned path is less than ten centimeters.
7. The method according to claim 1 further comprising:
selecting a substantially minimum radius turn for at least one turn path segment in the planned path if the minimum radius turn substantially supports opposite travel directions for the vehicle for adjacent travel rows throughout the designated area to provide a desired coverage or traversal of the designated area.
8. The method according to claim 1 further comprising:
selecting a bulb-shaped turn for at least one turn path segment in the planned path if the bulb-shaped turn substantially supports opposite travel directions for the vehicle for adjacent travel rows throughout the designated area to provide a desired coverage or traversal of the designated area.
9. The method according to claim 1 further comprising:
selecting a generally keyhole-shaped turn for at least one turn path segment in the planned path if the bulb-shaped turn substantially supports opposite travel directions for the vehicle for adjacent travel rows throughout the designated area to provide a desired coverage or traversal of the designated area.
10. The method according to claim 1 further comprising:
determining a treatment of at least one of soil and vegetation within the designated area.
11. The method according to claim 1 wherein the determined treatment is mowing the vegetation within the designated area to a defined height.
12. The method according to claim 1 further comprising the step of:
activating an implement of the vehicle generally coincident with a border of the designated area upon movement of the vehicle toward an inside of the designated area from outside the designated area prior to or during alignment of a critical portion of the implement with the border; and
deactivating the implement of the vehicle coincident with the border of the designated area upon movement of the vehicle toward an outside of the designated area from an inside of the designated area prior to or during alignment of a critical portion of the implement with the border.
13. The method according to claim 12 further comprising:
defining the border in terms of a series of reference geographic coordinates; and
tracking the operational vehicular coordinates of the vehicle and direction of vehicular movement of the vehicle during operation of the vehicle for comparison to the reference geographic coordinates.
14. The method according to claim 12 wherein the implement is selected from the group consisting of a cutting blade, a mowing blade, a plow, a harrow, a cutter, a thresher, a mowing deck, a harvester, a pump, a sprayer, an agricultural implement, a construction implement, an agricultural attachment, and a construction attachment.
15. A system for determining a planned path for a vehicle, the system comprising:
data storage storing at least one of mapped area data, pattern parameters, and planned path data; the mapped area data defining a border of a designated area within a work area, the pattern parameters determining a designated axis of the designated area, the planned path data aligning a series of generally parallel rows consistent with a travel axis having a known alignment with respect to the designated axis;
a vehicular guidance module defining one of the generally parallel rows as a starting row and pointing the vehicle in a starting direction along or generally parallel to the travel axis;
a steering system for engaging in a turn path segment under control of the vehicular guidance module after an end of the starting row to move the vehicle at least somewhat perpendicular to the travel axis between the starting row and a next row, a turn path segment having a turn radius greater than or equal to a minimum turning radius of the vehicle; the vehicular guidance module defining the turn path segment so as to skip one or more intervening parallel rows between the starting row and the next row, the starting row and the next row spatially separated by an effective implement width associated with the vehicle, less an overlap allowance.
16. The system according to claim 15 wherein the steering system is instructed to engage in an additional turn path segment after an end of the next row to move the vehicle at least somewhat perpendicular to the travel axis between the next row and a subsequent next row, the additional turn path segment having a turn radius greater than or equal to a minimum turning radius of the vehicle; the vehicular controller defining the turn path segment so as to skip one or more intervening parallel rows between the next row and the subsequent next row; the next row and the next subsequent row spatially separated by an effective implement width associated with the vehicle, less an overlap allowance.
17. The system according to claim 15 wherein the vehicular guidance module controls the vehicle to skip one or more intervening rows between each last row and each next successive row of the generally parallel rows for traversal by the vehicle as the vehicle progresses through the planned path from one end of the designated area to an opposite end.
18. The system according to claim 15 wherein the vehicular guidance module controls the vehicle to bypass one or more previously traversed intervening rows between each last row and each next successive row for traversal by the vehicle as the vehicle progresses through the planned path from one end of the designated area to an opposite end.
19. The system according to claim 15 wherein the vehicular guidance module controls the vehicle to head in opposite directions for traversal of adjacent rows of the generally parallel rows; the vehicular guidance module controlling the vehicle to overlap between two adjacent rows by the overlap allowance.
20. The system according to claim 19 wherein the overlap allowance between any two rows is generally less than ten centimeters.
21. The system according to claim 15 further comprising:
a path planner for selecting a substantially minimum radius turn for at least one turn path segment in the planned path if the minimum radius turn substantially supports opposite travel directions for the vehicle for adjacent travel rows throughout the designated area to traverse a desired portion of the designated area.
22. The system according to claim 15 further comprising:
a path planner for selecting a bulb-shaped turn for at least one turn path segment in the planned path if the bulb-shaped turn substantially supports opposite travel directions for the vehicle for adjacent travel rows throughout the designated area to traverse a desired portion of the designated area.
23. The system according to claim 15 further comprising:
a path planner for selecting a generally keyhole-shaped turn for at least one turn path segment in the planned path if the bulb-shaped turn substantially supports opposite travel directions for the vehicle for adjacent travel rows throughout the designated area to traverse a desired portion of the designated area.
24. The system according to claim 15 further comprising:
a vehicular controller for determining a treatment of at least one of vegetation and soil within the designated area.
25. The system according to claim 24 wherein the determined treatment is mowing the vegetation within the designated area.
26. The system according to claim 15 further comprising the step of:
activating an implement system of the vehicle generally coincident with the border of the designated area prior to or during movement of the vehicle toward an inside the designated area; and
deactivating the implement system of the vehicle coincident with the border prior to or upon movement of the vehicle toward an outside of the designated area.
27. The system according to claim 26 further comprising:
defining the border in terms of a series of reference geographic coordinates; and
tracking the operational vehicular coordinates of the vehicle and direction of vehicular movement of the vehicle during operation of the vehicle for comparison to the reference geographic coordinates.
28. The system according to claim 26 wherein the implement system is selected from the group consisting of a cutting blade, a mowing blade, a plow, a disc harrow, a cutter, a thresher, a mowing deck, a harvester, a pump, a sprayer, an agricultural implement, an agricultural attachment, a construction implement and a construction attachment.