Patent US3718497A successfully refreshed from Google Patents.
Patent EP0214633A1 successfully refreshed from Google Patents.
← Back to Patent Explorer
EP0214633A1 Expired / Lapsed EP ⏱️ 0.0 years remaining

Control system for hydraulically-operated construction machinery

Assignee: Hitachi Construction Machinery Co Ltd
•
Filing: 1986-09-05
•
Granted: —
•
Expires: 2006-09-05
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A control system for a hydraulic excavator having a prime mover (20, 110), revolution number control device (70; 120) for the prime mover, at least one variable displacement hydraulic pump (22, 23; 111) driven by the prime mover, displacement volume control device (60) for the pump, actuators (1a, 1b, 3, 5, 7, 9, 53; 113, 114) driven by pressurized fluid discharged from the pump and working elements (2, 4, 6, 8, 10; 101,103, 107,109) driven by the respective actuators. The control system includes maximum revolution number altering device (30; 73; 119; 130) for the prime mover associated with the revolution number control device, maximum displacement volume altering devices (31, 115) for the pump associated with the displacement volume control device, devices (34a, 34b; 56; 125, 126) for sensing the operation condition of the actuators, devices (32, 33; 34, 124) for selecting an operation mode for each working element and control devices (35, 35b; 123; 133). The maximum revolution number altering device provides at least one maximum revolution number of the prime mover and the maximum displacement volume altering device provides at least one maximum displacement volume so that maximum revolution numbers of the prime mover (N1, N2, N3; N TP , N TE , N D ) and maximum displacement volumes (q1, q2, q E , q P ) are arranged in a plurality of combinations (A, B, C, D). The plurality of combinations are set in association with the operation condition of the actuators and the selection of the operation mode. The control means selects a combination of the maximum revolution number of the prime mover and the maximum displacement volume of the pumps on basis of output signals of the sensors and selection devices, and drives the maximum revolution number altering device and the maximum displacement volume altering device to set the maximum revolution number of the prime mover and the maximum displacement volume of the hydraulic pump.

Inventors

  • 👤 Nobuya Okabe
  • 👤 Toichi Hirata
  • 👤 Kuniaki Yoshida
  • 👤 Genroku Sugiyama
  • 👤 Masakazu Haga
  • 👤 Hideaki Tanaka
  • 👤 Akira Tatsumi

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-02 16:41
CPC Classifications
F; F02; F02D; F02D29/00; F02D29/04; E; E02; E02F; E02F9/00; E02F9/20; E02F9/22; E02F9/2246; B; B60; B60W; B60W10/00; B60W10/04; B60W10/06; B60W10/30; B60W30/00; B60W30/18; B60W30/188; E02F9/2221; E02F9/2232; E02F9/2235; E02F9/2278; E02F9/2282; E02F9/2292; E02F9/2296; B60W2300/00; B60W2300/17; B60W2510/00; B60W2510/06; B60W2510/0638; B60W2510/30; B60W2540/00; B60W2540/215; B60W2710/00; B60W2710/06; B60W2710/0644; B60W2710/30

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 318 words
A control system for a hydraulically-operated construction machinery comprising a prime mover (20; 110), means (70; 120) for controlling the revolution number of said prime mover, at least one variable displacement hydraulic pump (22, 23; 111) driven by said prime mover, means (60) for controlling the displacement volume of the pump, a plurality of acutators (la, lb, 3, 5, 7, 9, 53; 113, 114) driven by pressurized fluid discharged from the pump and a plurality of working elements (2, 4, 6, 8, 10; 101, 103, 107, 109) driven by the respective actuators, characterized in that said control system comprises: means (30; 73; 119; 130) associated with said revolution number control means for altering the maximum revolution number of the prime mover; means (31; 115) associated with said displacement volume control means for altering the maximum displacement volume of the pump; means (34a, 34b; 56; 125, 126) for sensing the operation condition of the actuators; means (32, 33; 74, 124) for selecting an operation mode for each working element; the maximum revolution number altering means providing at least one maximum revolution number of the prime mover and the maximum displacement volume altering means providing at least one maximum displacement volume so that maximum revolution numbers of the prime mover and maximum displacement volumes of the pump are arranged in a plurality of combinations, said plurality of combinations being set in association with the operation condition of the actuators and the selection of the operation mode; and control means C35, 35b; 123; 133) for selecting a combination of the maximum revolution number and the maximum displacement volume on basis of output signals of the sensor means and selection means and driving the maximum revolution number altering means and the maximum displacement volume altering means to set the maximum revolution number of the prime mover and the maximum displacement volume of the hydraulic pump to the contents of the selected combination.
Claim 2
Dependent Claim 318 words
A control system for a hydraulically-operated construction machinery comprising a prime mover (20; 110), means (70; 120) for controlling the revolution number of said prime mover, at least one variable displacement hydraulic pump (22, 23; 111) driven by said prime mover, means (60) for controlling the displacement volume of the pump, a plurality of acutators (la, lb, 3, 5, 7, 9, 53; 113, 114) driven by pressurized fluid discharged from the pump and a plurality of working elements (2, 4, 6, 8, 10; 101, 103, 107, 109) driven by the respective actuators, characterized in that said control system comprises: means (30; 73; 119; 130) associated with said revolution number control means for altering the maximum revolution number of the prime mover; means (31; 115) associated with said displacement volume control means for altering the maximum displacement volume of the pump; means (34a, 34b; 56; 125, 126) for sensing the operation condition of the actuators; means (32, 33; 74, 124) for selecting an operation mode for each working element; the maximum revolution number altering means providing at least one maximum revolution number of the prime mover and the maximum displacement volume altering means providing at least one maximum displacement volume so that maximum revolution numbers of the prime mover and maximum displacement volumes of the pump are arranged in a plurality of combinations, said plurality of combinations being set in association with the operation condition of the actuators and the selection of the operation mode; and control means C35, 35b; 123; 133) for selecting a combination of the maximum revolution number and the maximum displacement volume on basis of output signals of the sensor means and selection means and driving the maximum revolution number altering means and the maximum displacement volume altering means to set the maximum revolution number of the prime mover and the maximum displacement volume of the hydraulic pump to the contents of the selected combination.
Claim 3
Dependent Claim 19 words
A control system as claimed in claim 1, wherein said selection means (32, 33; 74; 124) is manually operated.
Claim 4
Dependent Claim 340 words
A control system as claimed in claim 1, wherein said working elements comprise left and right travel devices (2) and other working elements (4, 6, 8, 10) than the travel devices, wherein said sensor means comprises first sensor means (34a) for sensing the operation condition of travel motors (la, lb) for driving the travel devices, and second sensor means (34b) for sensing the operation condition of other actuators (3, 5, 7, 9) than the travel motors for driving other working elements, wherein said selection means comprises first selection means (32) for selecting one of a power mode and an economy mode for other working elements than the travel devices, and second selection means for selecting one of a high-speed travelling mode and a low-speed travelling mode for the travel devices, wherein said plurality of combinations are set beforehand in association with the operation condition of the travel motors and other actuators and the selection of the power mode, economy mode, high-speed travelling mode and low-speed travelling mode and include a first combination (A) of a first maximum revolution number (N 1 ) of the prime mover and a first maximum displacement volume (ql) of the pumps both having a relatively large value, a second combination (B) of the first maximum revolution number (N 1 ) of the prime mover and a second maximum displacement volume (q 2 ) of the pumps smaller than the first maximum displacement volume (q l ), a third combination (C) of a second maximum revolution number of the prime mover (N 2 ) smaller than the first maximum revolution number of (N 1 ) and the first maximum displacement volume (q l ) of the pumps, and a fourth combination (D) of the second maximum revolution number (N2) of the prime mover and the second maximum displacement volume (q2), and wherein said control means (35b) selecting one of the four combinations (A, B, C, D) on the basis of output signals of the first and second sensor means and the first and second selection means.
Claim 5
Dependent Claim 98 words
A control system as claimed in claim 3, wherein said control means (34b) selects, when the travel motors (la, lb) are in operation, one of the first, third and fourth combinations (A, B, D) in accordance with the operation mode selected by the second selection means (33) irrespective of the operation condition of other actuators (3, 5, 7, 9) than the travel motors, and selects, when other actuators than the travel motors are in operation, one of the second and third combinations (B, C) on the basis of the operation mode selected by the first selection means (32).
Claim 6
Dependent Claim 94 words
A control system as claimed in claim 3, wherein said working elements further comprise a breaker (53) for crushing rocks and stones, wherein said sensor means further comprises third sensor means (56) for sensing the operation condition of an actuator for driving said breaker, and the first combination (A) is set beforehand in association with the operation condition of the actuator for driving the breaker, and said control means selects the first combination (A) on the basis of output signals of the third sensor means and the first and second selection means (32, 33).
Claim 7
Dependent Claim 149 words
A control system as claimed in claim 3, wherein said control means (35b) comprises a first determining means (S2 in Figs. 14-17 and 21) for determining with priority whether or not the travel motors (la, lb) are in operation on the basis of an output signal of the first sensor means (34a), and a second determining means (S4 in Figs. 15, 17 and 21) for determining, only when the travel motors have been determined by the first determining means not to be in operation, whether or not other actuators (3, 5, 7, 9) than the travel motors are in operation on the basis of an output signal of the second sensor means (34b), and .selects one of the combinations (A, B, C, D) on the basis of the determinations made by the first and second determining means and output signals of the first and second sensor means (32, 33).
Claim 8
Dependent Claim 117 words
A control system as claimed in claim 6, wherein said control means (35d) further comprises a third determining means (S6 in Fig. 15, S7 in Fig. 17 and S9 in Fig. 21) for determining whether or not the first selection means (32) is actuated after it is determined by the second determining means (S4 in Figs. 15, 17 and 21) that other actuators (3, 5, 7, 9) than the travel motors are not in operation, and selects the same combination as selected when it is determined by the second determining means that other actuators than the travel motors are in operation when it is determined by the third determining means that the first selection means is actuated.
Claim 9
Dependent Claim 145 words
A control system as claimed in claim 6, wherein said control means (35d) further comprises measuring means for measuring time period after it is determined by the second determining means (S4 in Figs. 16, 17 and 21) that other actuators (3, 5, 7, 9) than the travel motors are not in operation, and a third determining means (S6 in Figs. 16, 17 and 21 and S8 in Fig. 21) for determining whether or not the period of time after the determination has been made reaches a predetermined period of time on the basis of an output signal of said measuring means, and selects the same combination as selected when it is determined by the second determining means that other actuators than the travel motors are in operation when it is determined by the third determining means that the predetermined period of time has not elapsed.
Claim 10
Dependent Claim 223 words
A control system as claimed in claim 6, wherein said selection means (35d) further comprises a third selection means (74) for selecting whether or not the prime mover should be placed in an automatic idling mode, and wherein a fifth combination (F) of a third maximum revolution number (N3) of the prime mover for idling operation smaller than the second maximum revolution number (N 2 ) of the prime mover and the second maximum displacement volume (q 2 ) is set beforehand in association with the operation condition of the travel motors (la, lb) and other actuators (3, 5, 7, 9), and wherein said control means (35d) further comprises a third determining means (S6 in Fig. 21) for determining whether or not an automatic idling mode is selected by the third selection means (74) after it is determined by the second determining means (S4 in Fig. 21) that other actuators than the travel motors are not in operation, and selects the fifth combination (F) when it is determined by the third determining means that the automatic idling mode is selected and selects the same combination as selected when it is determined by the second determining means that other actuators than the travel motors are in operation when it is determined by the third determining means that the automatic idling mode is not selected.
Claim 11
Dependent Claim 308 words
A control system as claimed in claim 1, wherein the working elements comprise left and right travel devices (2) and other working elements (4, 6, 8, 10) than the travel devices, wherein said sensor means senses the operation condition of at least one of travel motors (la, lb) for driving the travel devices and other actuators (3, 5, 7, 9) than the travel motors for driving other working elements, wherein said selection means (33) selects a high-speed travelling mode or a low-speed travelling mode for the travel devices, wherein a first combination (A) of a first maximum revolution number (N1) of the prime mover and a first maximum displacement volume (ql) of the pumps both of relatively large value, a second combination (B) of the first maximum revolution number (N 1 ) of the prime mover and a second maximum displacement volume (q2) of the pumps smaller in value than the first maximum displacement volume (ql) of the pumps and a third combination (D) of a second maximum revolution number (N 2 ) of the prime mover smaller in value than the first maximum revolution number (N 1 ) of the prime mover and the second maximum displacement volume (q2) of the pumps are set beforehand in association with the operation condition of at least the travel motors and other actuators and the selection of the high-speed travelling mode and the low-speed travelling mode, and wherein said control means (35d) selects, on the basis of output signals of the sensor means and selection means, the first combination (A) when the travel motors only are in operation and the high-speed travelling mode is selected, the third combination (D) when the travel motors only are in operation and the low-speed travelling mode is selected, and the second combination (B) when other actuators than the travel motors only are in operation.
Claim 12
Dependent Claim 187 words
A control system as claimed in claim 1, wherein said working elements comprise travel devices (10) and other working elements (103, 107 - 109), wherein said selection means selects a power-mode or an economy mode of said travel devices wherein a first combination of a first maximum revolution number (N , N ) of the prime mover relatively large value and a second maximum displacement volume (qp) of the pumps smaller in value than a first maximum displacement volume (q F ) of the pumps relatively large value and a second combination of a second maximum revolution number (N E , N TE ) of the prime mover smaller in value than the first maximum revolution number of the prime mover and the first maximum displacement volume (q E ) of the pumps are set beforehand in association with the selection of the power mode or the economy mode, and wherein said control means (123; 133) selects, on the basis of an output signal of the selection means, the first combination when the power mode is selected and the second combination when the economy mode is selected.
Claim 13
Dependent Claim 147 words
A control system as claimed in claim 11, wherein said sensor means comprises first sensor means (125) for sensing the operation condition of travel motors (113) for driving the travel devices (101) and second sensor means (126) for sensing the operation condition of other actuators (114) than the travel motors for driving other working elements, wherein the first and second combinations are set beforehand in association with the operation condition of the travel motors and other actuators, and wherein said control means (133) selects, on the basis of output signals of the first and second sensor means (125, 126) and the selection means (124), the first combination when the travel motors are in operation and the power mode is selected and the second combination when the travel motors are in operation and the economy mode is selected and other actuators than the travel motors are in operation.
Claim 14
Dependent Claim 105 words
A control system as claimed in claim 12, wherein a third combination of a third maximum revolution number (N D ) of the prime mover smaller in value than the second maximum revolution number (NTE) of the prime mover and the first maximum displacement volume (q E ) of the pumps is set beforehand in association with the operation condition of other actuator (114) than the travel motor, and wherein said control means (133) selects the second combination when the travel motors are in operation and the economy mode is selected and the third combination when other actuators than the travel motors are in operation.

References Cited (Backward Citations)

BE646519A Cited
FR1400491A Cited
US3922855A Cited
US4017216A Cited
US4288196A Cited
JPS5716349A Cited
EP0076485A1 Cited
JPS58135341A Cited
EP0159835A1 Cited

USPTO Annuity & Maintenance Windows

Maintenance schedule is calculated for granted US utility patents.

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag