JP3645740B2 - Construction machine control equipment - Google Patents

Description

この表１に示すように、本実施形態における最適ポンプ流量制御を行なった場合、従来のポンプ流量制御に比べ、地ならし作業時の燃費を約２５％向上させることができることがわかる。なお、バケット用操作部材５４ｃやスティック用操作部材５４ｂがフル操作された場合の燃費は従来の場合とほとんど変わらない。
【００９９】
したがって、本実施形態によれば、ブーム用操作部材５４ａ，スティック用操作部材５４ｂ及びバケット用操作部材５４ｃの操作量に基づいてブームアップ微操作，スティックイン微操作及びバケットイン微操作が同時に行なわれた場合にいわゆる地ならし作業であると判定し、この地ならし作業において最適なポンプ流量となるように油圧ポンプ５１，５２の傾転角制御を行なうため、油圧ポンプ５１，５２を駆動するエンジン５０の出力ロスを抑制することができ、ひいては燃費を良くすることができるという利点がある。
【０１００】
また、ブーム用操作部材５４ａ，スティック用操作部材５４ｂ及びバケット用操作部材５４ｃの操作量に基づいてブームアップ微操作，スティックイン微操作及びバケットイン微操作が同時に行なわれた場合に地ならし作業であると判定し、ポンプ吐出圧が過剰に上昇しないようにブーム用操作部材５４ａ，スティック用操作部材５４ｂ及びバケット用操作部材５４ｃの操作量に応じて油圧ポンプ５１，５２の傾転角制御を行なうため、つまりポンプ吐出流量を減らすように油圧ポンプ５１，５２の傾転角を制御するため、油圧ポンプ５１，５２を駆動するエンジン５０の出力ロスを抑制することができ、ひいては燃費を良くすることができるという利点がある。
【０１０１】
なお、上述の実施形態では、ブームアップ微操作，スティックイン微操作及びバケットイン微操作が行なわれる場合について説明したが、これに限られるものではなく、ブームダウン微操作（ブーム微操作），スティックアウト微操作（スティック微操作）及びバケットオープン微操作（バケット微操作）が行なわれる場合であっても、本発明を同様に適用できる。
【０１０２】
この場合、ブーム微操作判定手段２は、ブーム用操作部材５４ａの操作量に基づいてブームダウン微操作が行なわれたかを判定するものとして構成され、スティック微操作判定手段３は、スティック用操作部材５４ｂの操作量に基づいてスティックアウト微操作が行なわれたかを判定するものとして構成されるとともに、バケット微操作判定手段４は、バケット用操作部材５４ｃの操作に基づいてバケットオープン微操作が行なわれたかを判定するものとして構成される。そして、ポンプ傾転角制御手段５が、ブーム微操作判定手段２，スティック微操作判定手段３及びバケット微操作判定手段４の判定結果に基づいて油圧ポンプ５１，５２の傾転角制御を行なうことになる。
【０１０４】
【発明の効果】
以上詳述したように、請求項１，２，３記載の本発明の建設機械の制御装置によれば、ブーム用操作部材，スティック用操作部材及びバケット用操作部材の操作量に基づいてブームアップ微操作，スティックイン微操作及びバケットイン微操作が同時に行なわれた場合にいわゆる地ならし作業であると判定し、この地ならし作業において最適なポンプ流量となるように油圧ポンプの傾転角制御を行なうため、油圧ポンプを駆動するエンジンの出力ロスを抑制することができ、ひいては燃費を良くすることができるという利点がある。
【０１０５】
また、請求項４記載の本発明の建設機械の制御装置によれば、ブーム用操作部材，スティック用操作部材及びバケット用操作部材の操作量に基づいてブームアップ微操作，スティックイン微操作及びバケットイン微操作が同時に行なわれた場合に地ならし作業であると判定し、ポンプ吐出圧が過剰に上昇しないようにブーム用操作部材，スティック用操作部材及びバケット用操作部材の操作量に応じてポンプ吐出流量を減らすように油圧ポンプの傾転角を制御するため、油圧ポンプを駆動するエンジンの出力ロスを抑制することができ、ひいては燃費を良くすることができるという利点がある。
【図面の簡単な説明】
【図１】本発明の一実施形態にかかる建設機械の制御装置における油圧ポンプの傾転角制御を説明するための制御ブロック図である。
【図２】本発明の一実施形態にかかる建設機械の制御装置の全体構成図である。
【図３】本発明の一実施形態にかかる建設機械の制御装置の制御弁を説明するための模式図である。
【図４】本発明の一実施形態にかかる建設機械の制御装置におけるネガティブフローコントロールの要求流量とネガコン圧との関係を示す図である。
【図５】本発明の一実施形態にかかる建設機械の制御装置におけるネガティブフローコントロールの許容流量とポンプ吐出圧との関係を示す図である。
【図６】本発明の一実施形態にかかる建設機械の制御装置におけるネガティブフローコントロールを説明するためのフローチャートである。
【図７】本発明の一実施形態にかかる建設機械の制御装置におけるポンプ傾転角制御を説明するためのフローチャートである。
【図８】従来の建設機械を示す模式的斜視図である。
【符号の説明】
１ コントローラ（制御手段）
２ ブームアップ微操作判定手段（ブーム微操作判定手段）
３ スティックイン微操作判定手段（スティック微操作判定手段）
４ バケットイン微操作判定手段（バケット微操作判定手段）
５ ポンプ傾転角制御手段
５１ 第１油圧ポンプ
５２ 第２油圧ポンプ
５４ 操作部材
５４ａ ブーム用操作部材
５４ｂ スティック用操作部材
５４ｃ バケット用操作部材
７２，７３，７４，７５ 圧力センサ
１０３ ブーム
１０４ スティック
１０８ バケット[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a control device for a construction machine that controls the operation of hydraulic actuators such as a boom cylinder and a bucket cylinder by controlling the pump discharge flow rate by controlling the tilt angle of a hydraulic pump provided in the construction machine.
[0002]
[Prior art]
In general, a construction machine such as a hydraulic excavator includes an upper swing body 102, a lower traveling body 100, and a work device 118 as shown in FIG.
The lower traveling body 100 includes a right truck 100R and a left truck 100L that can be driven independently from each other. On the other hand, the upper revolving body 102 is provided so as to be able to swivel in a horizontal plane with respect to the lower traveling body 100. .
[0003]
The working device 118 mainly includes a boom 103, a stick 104, a bucket 108, and the like. The boom 103 is pivotally attached to the upper swing body 102. A stick 104 is connected to the tip of the boom 103 so as to be rotatable in the same vertical plane.
A boom drive hydraulic cylinder (boom cylinder, hydraulic actuator) 105 for driving the boom 103 is provided between the upper swing body 102 and the boom 103, and between the boom 103 and the stick 104. A stick driving hydraulic cylinder (stick cylinder, hydraulic actuator) 106 for driving the stick 104 is provided. Further, a bucket driving hydraulic cylinder (bucket cylinder, hydraulic actuator) 107 for driving the bucket 108 is provided between the stick 104 and the bucket 108.
[0004]
Further, each of the cylinders 105 to 107 described above includes a plurality of control valves such as a hydraulic pump driven by an engine (mainly a diesel engine), a boom control valve, a stick control valve, and a bucket control valve. A circuit (not shown) is connected, hydraulic oil of a predetermined hydraulic pressure is supplied from the hydraulic pump via each control valve, and driven in accordance with the supplied hydraulic pressure in this way. Yes.
[0005]
Here, the plurality of control valves are respectively installed in hydraulic oil supply passages (hydraulic pump-cylinder passage, PC passage) that supply / discharge hydraulic oil to / from the cylinders 105 to 107 and the hydraulic pump. In addition to the C-T throttle interposed in the throttle and the hydraulic oil discharge passage (cylinder-tank passage, C-T passage), it also has a bypass passage throttle interposed in the bypass passage leading from the hydraulic pump to the reservoir tank.
[0006]
With such a configuration, the boom 103 can rotate in the directions of arrows a and b in the drawing, the stick 104 can rotate in the directions of arrows c and d in the drawing, and the bucket 108 can rotate in the directions of arrows e and f in the drawing. It is configured.
Note that the rotation of the boom 103 in the direction of arrow a in the drawing is called boom up, and the rotation in the direction of arrow b in the drawing is called boom down. Further, the rotation of the stick 104 in the direction of the arrow c in the drawing is called stick-out, and the rotation in the direction of the arrow d in the drawing is called stick-in. Further, the rotation of the bucket 108 in the direction of arrow e in the drawing is referred to as bucket open, and the rotation in the direction of arrow f in the drawing is referred to as bucket-in.
[0007]
In the operation operation chamber 101, a left lever, a right lever, a left pedal, and a right pedal are provided as operation members for controlling the operation of the hydraulic excavator (running, turning, boom turning, stick turning, and bucket turning). Etc. are provided.
For example, when the operator operates the operation members such as the levers and the pedals, the control valves of the hydraulic circuit are controlled, and the cylinders 105 to 107 are driven, whereby the boom 103, the stick 104, and the bucket are driven. 108 etc. can be rotated.
[0008]
A pilot hydraulic circuit is provided to control each control valve. Accordingly, in order to operate the boom 103 and the stick 104, the boom operation member and the stick operation member in the operation operation chamber 101 are operated, and the pilot hydraulic pressure is supplied to the boom control valve and the stick control valve through the pilot oil passage. The boom control valve and the stick control valve are driven to required positions. As a result, the hydraulic oil to the boom driving hydraulic cylinder 105 and the stick driving hydraulic cylinder 106 is supplied and discharged, and the cylinders 105 and 106 are extended and driven to a required length.
[0009]
As described above, in the hydraulic excavator, the cylinders 105 to 107 are driven to extend and retract, and the working devices 118 such as the boom 103, the stick 104, and the bucket 108 are driven to perform various operations such as excavation work. Yes.
By the way, as one operation in such various works, for example, there is a so-called ground leveling work (leveling operation), and in the ground leveling work, the above-described boom-up, stick-in and bucket-in are operated simultaneously.
[0010]
Here, when the boom-up operation is performed, the boom 103 is driven as follows.
That is, when the boom up operation is performed, the boom driving hydraulic cylinder 105 may be extended to raise the boom 103. In this case, pilot hydraulic pressure is applied to the boom control valve through the pilot oil passage. Thereby, the spool position of the boom control valve becomes the boom raising position, and the hydraulic oil from the hydraulic pump is supplied to one chamber of the boom driving hydraulic cylinder 105 through the oil passage. On the other hand, hydraulic oil in the other chamber of the boom driving hydraulic cylinder 105 is discharged to the tank through the oil passage. As a result, the boom 103 is rotated upward as indicated by an arrow a in FIG. 8 while the boom driving hydraulic cylinder 105 is extended.
[0011]
When a stick-in operation is performed, the stick 104 is driven as follows.
That is, when the stick-in operation is performed, the stick driving hydraulic cylinder 106 may be extended to lower the stick 104. In this case, the pilot hydraulic pressure is applied to the stick control valve through the pilot oil passage. As a result, the spool position of the stick control valve becomes the stick lowering position, and the hydraulic oil from the hydraulic pump is supplied to one chamber of the stick driving hydraulic cylinder 106 through the oil passage. On the other hand, the hydraulic oil in the other chamber of the stick driving hydraulic cylinder 106 is discharged to the tank through the oil passage. Accordingly, the stick 104 is rotated downward as shown by an arrow d in FIG. 8 while the stick driving hydraulic cylinder 106 is extended.
[0012]
Further, when the bucket-in operation is performed, the bucket 108 is driven as follows.
That is, when the bucket-in operation is performed, the bucket driving hydraulic cylinder 107 may be extended to close the bucket 108. In this case, the pilot hydraulic pressure is applied to the bucket control valve through the pilot oil passage. As a result, the spool position of the bucket control valve becomes the bucket closed position, and hydraulic oil from the hydraulic pump is supplied to one chamber of the bucket drive hydraulic cylinder 107 through the oil passage. On the other hand, hydraulic oil in the other chamber of the bucket driving hydraulic cylinder 107 is discharged to the tank through the oil passage. As a result, the bucket 108 is moved in the closing direction as indicated by an arrow f in FIG. 8 while the bucket driving hydraulic cylinder 107 extends.
[0013]
In order to ensure the simultaneous operability of the boom 103, the stick 104, and the bucket 108, the pressure of the hydraulic oil discharged from the hydraulic pump is the maximum pressure (maximum pressure value) of the operating pressures of these work machines. ) To be set. As a method of ensuring the pressure of the hydraulic oil, the pump discharge flow rate is slightly increased from the total flow rate of the hydraulic oil supplied to each cylinder, and the excess pump discharge flow rate is reduced by the bypass passage throttle of the control valve to increase the pressure. It is common.
[0014]
[Problems to be solved by the invention]
By the way, as described above, there is, for example, a leveling work as a work for simultaneously operating the boom 103, the stick 104, and the bucket 108. The leveling work is performed by a fine operation for any of boom-up, stick-in and bucket-in. Moreover, since the load direction of the stick-in and bucket-in in this case is the self-weight drop direction of the linkage, the flow rate of the hydraulic oil discharged from the hydraulic pump is not necessary in these operations, and the pressure of the hydraulic oil is not so much. Not necessary.
[0015]
In such leveling work, the same amount of hydraulic oil as that discharged from the hydraulic pump is supplied during other work in which any one of the boom 103, the stick 104, and the bucket 108 is operated without fine operation. Therefore, the hydraulic oil is supplied at an excessive flow rate, and the pump discharge pressure from the hydraulic pump is excessively increased.
[0016]
As described above, since the pump flow rate control of the hydraulic pump is performed so that the pump discharge pressure becomes excessive, a loss occurs in the engine output for driving the hydraulic pump correspondingly, leading to deterioration of fuel consumption. .
The present invention was devised in view of such problems, and performs pump flow control so that the pump discharge pressure does not increase excessively when a boom, stick, or bucket is finely operated during so-called leveling work. Thus, it is an object of the present invention to provide a construction machine control device capable of suppressing loss of engine output and thus preventing deterioration of fuel consumption.
[0017]
[Means for Solving the Problems]
Therefore, the construction machine control device according to the first aspect of the present invention includes a hydraulic pump that discharges hydraulic oil in the tank and an operator. Configured to output an electrical signal according to the operation amount A plurality of operation members; and a control means for controlling a discharge flow rate from the hydraulic pump, wherein the control means is a boom operation member among the plurality of operation members. Electrical signal from Boom fine operation determining means for determining whether or not a boom fine operation has been performed based on the above, and a stick operation member among the plurality of operation members Electrical signal from Stick fine operation determining means for determining whether or not a stick fine operation has been performed based on the above, and a bucket operation member among the plurality of operation members Electrical signal from Fine operation determination means for determining whether a fine bucket operation has been performed based on the above, fine boom operation determination means, stick fine operation determination means, and fine bucket operation determination means When it is determined that the boom fine operation, the stick fine operation and the bucket fine operation are performed simultaneously, the boom operation member, the stick operation member, and the bucket operation member are operated according to the operation amount. Control the tilt angle of the hydraulic pump On the other hand, when it is determined that any one of the boom fine operation, the stick fine operation, and the bucket fine operation is not performed, the tilt angle control of the hydraulic pump is performed by the negative flow control. And a pump tilt angle control means.
[0018]
According to a second aspect of the present invention, there is provided a control device for a construction machine that supplies and discharges hydraulic oil to and from a hydraulic pump that discharges hydraulic oil in a tank. Therefore, the downstream side of the bypass passage communicating the hydraulic pump and the tank A pressure sensor, a plurality of operation members configured to output an electric signal according to an operation amount by an operator, and a control means for controlling a discharge flow rate from the hydraulic pump, the control means Is a boom fine operation determination means for determining whether a boom fine operation has been performed based on an electric signal from a boom operation member among the plurality of operation members, and a stick for the stick among the plurality of operation members. A stick fine operation determination means for determining whether or not a stick fine operation has been performed based on an electric signal from the operation member, and a bucket fine operation based on an electric signal from the bucket operation member among the plurality of operation members. The bucket fine operation determining means for determining whether the operation has been performed, the boom fine operation determining means, the stick fine operation determining means, and the bucket fine operation determining means. If it is determined that the minute operation, the stick operation, and the bucket operation are performed at the same time, the hydraulic pump is tilted according to the operation amounts of the boom operation member, the stick operation member, and the bucket operation member. When it is determined that any one of the boom fine operation, the stick fine operation, and the bucket fine operation is not performed while performing the rotation angle control, the tilt angle of the hydraulic pump is determined based on the detection signal from the pressure sensor. And a pump tilt angle control means for performing control.
According to a third aspect of the present invention, there is provided a construction machine control device according to the first or second aspect, wherein the boom fine operation determining means determines whether a boom up fine operation has been performed, The stick fine operation determining means is configured to determine whether a stick-in fine operation has been performed, and the bucket fine operation determining means is configured to determine whether a bucket-in fine operation has been performed. When the turning angle control means determines that the boom fine operation, the stick-in fine operation, and the bucket-in fine operation are simultaneously performed by the boom fine operation determination means, the stick fine operation determination means, and the bucket fine operation determination means. The tilt angle of the hydraulic pump is controlled according to the operation amounts of the boom operation member, the stick operation member, and the bucket operation member. It is characterized in that Nau.
[0019]
According to a fourth aspect of the present invention, there is provided a construction machine control device according to the first aspect. Or 3 In the configuration described, The The pump tilt angle control means is controlled by the boom fine operation determining means, the stick fine operation determining means, and the bucket fine operation determining means. Fine Operation, sticky Fine Operation and bucket Fine Operation at the same time If it is determined that it was done Is Discharge flow rate from the hydraulic pump Is due to the negative flow control Less than the discharge flow rate from the hydraulic pump Ru Thus, the tilt angle control of the hydraulic pump is performed.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
First, the construction machine according to the present embodiment will be described.
This construction machine is a construction machine (working machine) such as a hydraulic excavator as already described in the prior art (see FIG. 8), and includes an upper swing body 102, a lower traveling body 100, and a work device 118. Yes.
[0021]
The lower traveling body 100 includes a right truck 100R and a left truck 100L that can be driven independently from each other. On the other hand, the upper revolving body 102 is provided so as to be able to swivel in a horizontal plane with respect to the lower traveling body 100. .
The working device 118 mainly includes a boom 103, a stick 104, a bucket 108, and the like. The boom 103 is pivotally attached to the upper swing body 102. A stick 104 is connected to the tip of the boom 103 so as to be rotatable in the same vertical plane.
[0022]
A boom drive hydraulic cylinder (boom cylinder, hydraulic actuator) 105 for driving the boom 103 is provided between the upper swing body 102 and the boom 103, and between the boom 103 and the stick 104. A stick driving hydraulic cylinder (stick cylinder, hydraulic actuator) 106 for driving the stick 104 is provided. Further, a bucket driving hydraulic cylinder (bucket cylinder, hydraulic actuator) 107 for driving the bucket 108 is provided between the stick 104 and the bucket 108.
[0023]
With such a configuration, the boom 103 can be rotated in directions a and b in the drawing, the stick 104 can be rotated in directions c and d in the drawing, and the bucket 108 can be rotated in directions e and f in the drawing. Yes.
Here, FIG. 2 is a diagram schematically showing the main part of the hydraulic circuit of such a hydraulic excavator.
[0024]
As shown in FIG. 2, the left track 100L and the right track 100R described above are provided with traveling motors 109L and 109R as independent power sources. A turning motor 110 for turning the upper turning body 102 is provided.
These travel motors 109L and 109R and the turning motor 110 are configured as hydraulic motors that are operated by hydraulic pressure, and as described later, a plurality of (here, two) driven by an engine (mainly a diesel engine) 50. The hydraulic oil from the hydraulic pumps 51, 52 is supplied at a predetermined pressure via the hydraulic circuit 53, and the hydraulic motors 109L, 109R, 110 are driven in accordance with the hydraulic pressure supplied in this way. It has become.
[0025]
Here, the hydraulic pumps 51 and 52 discharge hydraulic oil in the reservoir tank 70 as a predetermined hydraulic pressure. Here, as the swash plate rotary piston pump (piston type variable capacity pump, variable discharge amount type piston pump) It is configured. These hydraulic pumps 51 and 52 can adjust the pump discharge flow rate by changing the stroke amount of a piston (not shown) provided in the hydraulic pump.
[0026]
That is, in these hydraulic pumps 51 and 52, one end of the piston is configured to come into contact with a swash plate (creep plate: not shown), and the inclination (tilt angle) of the swash plate is described later. The pump discharge flow rate can be adjusted by changing the stroke amount of the piston by changing it based on the operation signal from.
[0027]
As described above, the inclination of the swash plate can be changed based on the operation signal from the controller 1, and in addition to the pressure of the hydraulic oil in the oil passage constituting the hydraulic circuit, Since the amount of operation can be taken into account, the operator's driving feeling can be improved as compared with the conventional one in which the pressure of the hydraulic oil in the oil passage is guided to change the inclination of the swash plate. .
[0028]
Further, the engine 50 can set the engine speed by an operator switching the engine speed setting dial. Here, the maximum engine speed (for example, about 2000 rpm) and the minimum engine speed (for example, about 1000 rpm) are set. ) Can be switched to multiple levels. It should be noted that the engine speed is not limited to switching in stages as described above, and may be one that can be changed smoothly. Further, the total horsepower of the engine 50 is consumed to drive these hydraulic pumps 51 and 52 and a pilot pump 83 described later.
[0029]
Also for each of the cylinders 105 to 107, hydraulic oil supplied from a plurality (two in this case) of hydraulic pumps 51 and 52 driven by the engine 50 is the same as the traveling motors 109 </ b> L and 109 </ b> R and the turning motor 110. It is driven by the hydraulic pressure.
The operation chamber 101 includes a plurality of levers such as a left lever, a right lever, a left pedal, and a right pedal for controlling the operation of the excavator (running, turning, boom turning, stick turning, and bucket turning). An operation member 54 is provided. These operation members 54 are configured as electric operation members (for example, electric operation levers), and output an electric signal corresponding to the operation amount to a controller (control means) 1 described later.
[0030]
For example, when the operator operates these operation members 54, the control valves 57 to 60 and 62 to 65 interposed in the hydraulic circuit 53 are controlled, and the cylinders 105 to 107 and the hydraulic motors 109L and 109R are controlled. 110 are driven. Accordingly, the upper swing body 102 can be turned, the boom 103, the stick 104, the bucket 108, and the like can be turned, and the hydraulic excavator can be run.
[0031]
In addition, what is operated when the boom 103 is rotated is referred to as a boom operation member 54a, and what is operated when the stick 104 is rotated is referred to as a stick operation member 54b, and when the bucket 108 is rotated. What is operated is referred to as a bucket operating member 54c.
Next, the hydraulic circuit 53 for controlling each of these cylinders will be described.
[0032]
As shown in FIG. 2, the hydraulic circuit 53 includes a first circuit unit 55 and a second circuit unit 56.
Among these, the 1st circuit part 55 is the oil path 61 connected to the 1st hydraulic pump 51, the right travel motor control valve 57 interposed in the oil path 61, the bucket control valve 58, and 1st boom use. And a control valve 59, a control valve such as a second stick control valve 60, and the like.
[0033]
Then, the hydraulic oil from the first hydraulic pump 51 is supplied to the right travel motor 109R via the oil passage 61 and the right travel motor control valve 57 to drive the right travel motor 109R. The hydraulic oil from the first hydraulic pump 51 is supplied to the bucket drive hydraulic cylinder 107 via the oil passage 61 and the bucket control valve 58, and via the oil passage 61 and the first boom control valve 59. Is supplied to the boom driving hydraulic cylinder 105, and further supplied to the stick driving hydraulic cylinder 106 via the oil passage 61 and the second stick control valve 60, whereby each cylinder 105, 106, 107 is driven. It is like that.
[0034]
Further, a throttle (restriction with a relief valve) 81 is provided on the downstream side of the oil passage 61 of the first circuit unit 55, and the hydraulic oil from the first hydraulic pump 51 is returned to the reservoir tank 70 through the throttle 81. It has become.
The second circuit unit 56 includes an oil passage 66 connected to the second hydraulic pump 52, a left travel motor control valve 62, a swing motor control valve 63, and a first stick control valve interposed in the oil passage 66. 64, a control valve such as a second boom control valve 65, and a throttle 82.
[0035]
Then, the hydraulic oil from the second hydraulic pump 52 is supplied to the left travel motor 109L via the oil passage 66 and the left travel motor control valve 62, whereby the left travel motor 109L is driven. Yes. Further, the hydraulic oil from the second hydraulic pump 52 is supplied to the swing motor 110 via the oil passage 66 and the swing motor control valve 63, whereby the swing motor 110 is driven. Further, the hydraulic oil from the second hydraulic pump 52 is supplied to the stick driving hydraulic cylinder 106 via the oil passage 66 and the first stick control valve 64, and the oil passage 66 and the second boom control valve 65. Is supplied to the boom drive hydraulic cylinder 105, whereby the cylinders 105 and 106 are driven.
[0036]
Further, a throttle (restriction with a relief valve) 82 is provided on the downstream side of the oil passage 66 of the second circuit portion 56, and the hydraulic oil from the second hydraulic pump 52 is returned to the reservoir tank 70 through the throttle 82. It has become.
In addition, each control valve 57-60, 62-65 is accommodated in the control unit which is not shown in figure.
[0037]
As described above, in the present embodiment, the second circuit portion 56 of the second circuit unit 56 is supplied so that sufficient hydraulic oil is supplied to the stick 104 that is important in the work of the construction machine even during the simultaneous operation with the other work machines 118. In addition to the hydraulic oil from the hydraulic pump 52, the hydraulic oil from the first hydraulic pump 51 of the first circuit unit 55 is also supplied to the stick driving hydraulic cylinder 106.
[0038]
For this reason, the first stick control valve 64 is interposed in the oil passage 66 of the second circuit portion 56, and the second stick control valve 60 is interposed in the oil passage 61 of the first circuit portion 55. The first stick control valve 64 is controlled by the proportional control valves 64a and 64b, and the second stick control valve 60 is controlled by the proportional control valves 60a and 60b. Oil can be supplied and discharged.
[0039]
Similarly, in addition to the hydraulic oil from the first hydraulic pump 51 of the first circuit unit 55, the second circuit is provided so that sufficient hydraulic oil is supplied to the boom 103 during simultaneous operation with the other work implements 118. The hydraulic oil from the second hydraulic pump 52 of the part 56 is also supplied to the boom driving hydraulic cylinder 105.
For this reason, the first boom control valve 59 is interposed in the oil passage 61 of the first circuit portion 55, and the second boom control valve 65 is interposed in the oil passage 66 of the second circuit portion 56. The first boom control valve 59 is controlled by the proportional control valves 59a and 59b, and the second boom control valve 65 is controlled by the proportional control valves 65a and 65b. Oil can be supplied and discharged.
[0040]
In this embodiment, a stick regeneration valve 76 is interposed in the oil passages 67 and 68 for supplying and discharging the hydraulic oil to and from the hydraulic cylinder 106 for driving the stick, and the hydraulic oil is supplied from the hydraulic oil discharge side oil passage. A predetermined amount of hydraulic oil can be regenerated in the supply side oil passage.
Similarly, boom regeneration valves 77 are also interposed in the oil passages 78 and 79 for supplying and discharging the hydraulic oil to and from the boom drive hydraulic cylinder 105, and the hydraulic oil supply-side oil passage from the hydraulic oil discharge-side oil passage. A predetermined amount of hydraulic fluid can be regenerated.
[0041]
Here, as shown in FIG. 3, each of the control valves 57 to 60 and 62 to 65 is configured as a spool valve, and each includes a plurality of (here, five) throttles.
That is, as shown in FIG. 3, each control valve 57-60, 62-65 is provided with an oil passage (hydraulic oil supply passage) that connects the first hydraulic pump 51, the second hydraulic pump 52, and the stick driving hydraulic cylinder 106. , PC passages) 61a, 66a, an oil passage (hydraulic oil discharge passage, CT passage) 66b communicating with the PC throttle 8 and the stick driving hydraulic cylinder 106 and the reservoir tank 70, A bypass passage throttle 10 interposed in oil passages (bypass passages) 61b and 66c that connect the CT throttle 9 interposed in 69, the first hydraulic pump 51, the second hydraulic pump 52, and the reservoir tank 70. And is configured.
[0042]
In FIG. 3, the stick control valves 60 and 64 are in the stick lowering position, but the stick control valves 60 and 64 are moved upward in FIG. By interposing the bypass passage throttle 10 in the bypass passages 61b and 66c, the stick control valves 60 and 64 can be set to the neutral position, and the stick control valves 60 and 64 are at the top in FIG. And the P-C throttle 8 of the stick control valves 60, 64 is inserted in the PC passages 61a, 66a, and the C-T throttle 9 of the stick control valves 60, 64 is set to C-T. By interposing the passages 66b and 69, the stick control valves 60 and 64 can be set to the stick raising position.
[0043]
In setting the diameters of the apertures 8, 9, and 10, all work devices 118 are operated when each operation member 54 is fully operated in order to ensure the linkage of the work devices 118 such as the boom 103 and the stick 104. Is considered to move.
Then, the opening area of the oil passages 61a, 66a that communicates the first hydraulic pump 51, the second hydraulic pump 52 and the stick driving hydraulic cylinder 106 by the PC throttle 8 (the opening area of the hydraulic oil supply passage, P− C opening area) is adjusted.
[0044]
The opening area of the oil passages 66b and 69 (the opening area of the hydraulic oil discharge passage, the C-T opening area) for communicating the stick driving hydraulic cylinder 106 and the reservoir tank 70 is adjusted by the CT throttle 9.
By the bypass passage throttle 10, the opening areas (opening areas of the bypass passages) of the oil passages 61 b and 66 c that communicate the first hydraulic pump 51, the second hydraulic pump 52, and the reservoir tank 70 are adjusted.
[0045]
By the way, in this embodiment, as shown in FIG. 2, in order to control each control valve 57-60, 62-65, the pilot pump 83 and proportional pressure reducing valve 57a-60a, 57b-60b, 62a-65a, A pilot hydraulic circuit having 62b to 65b is provided. In FIG. 2, only the pilot pump 83 and the proportional pressure reducing valves 57a to 60a, 57b to 60b, 62a to 65a, and 62b to 65b provided in the pilot hydraulic circuit are illustrated, and the pilot oil pressure is omitted. Indicated by P.
[0046]
Here, the proportional pressure reducing valves 57a to 60a, 57b to 60b, 62a to 65a, and 62b to 65b are electromagnetic valves and are operated by an operation signal from the controller 1 described later. As a result, the pilot hydraulic pressure from the pilot pump 83 is applied to the control valves 57 to 60 and 62 to 65 as a predetermined pressure based on the operation signal from the controller 1.
[0047]
With such a configuration, for example, to operate the boom 103, the boom operation member 54a in the operation operation chamber 101 is operated, and the pilot hydraulic pressure P from the pilot pump 83 is controlled through the pilot oil passage (not shown). Acting on the valves 59 and 65, the boom control valves 59 and 65 are moved to the required positions. As a result, the hydraulic oil in the boom drive hydraulic cylinder 105 is supplied and discharged, and these cylinders 105 are expanded and contracted to a required length, whereby the boom 103 is operated.
[0048]
For example, in order to rotate the boom 103 downward (boom down), the boom driving hydraulic cylinder 105 may be contracted. In this case, the pilot hydraulic pressure is applied to the first boom control valve 59 through the pilot oil passage. As a result, the spool position of the first boom control valve 59 becomes the boom lower side rotation position (boom down position), and the hydraulic oil from the first hydraulic pump 51 of the first circuit portion 55 is supplied to the oil passages 95 and 79. Then, it is supplied to one chamber of the boom driving hydraulic cylinder 105 and supplied to one chamber of the boom driving hydraulic cylinder 105. On the other hand, the hydraulic oil in the other chamber of the boom drive hydraulic cylinder 105 is discharged to the reservoir tank 70 through the oil passages 78 and 69. Thereby, the boom 103 is rotated downward as shown by an arrow b in FIG. 8 while the boom driving hydraulic cylinder 105 contracts.
[0049]
Conversely, in order to rotate the boom 103 upward (boom up), the boom driving hydraulic cylinder 105 may be extended. In this case, the pilot hydraulic pressure is applied to the first boom control valve 59 and the second boom control valve 65 through the pilot oil passage. As a result, the spool positions of the first boom control valve 59 and the second boom control valve 65 become the boom upper rotation position (boom up position), and the first circuit section 55 operates from the first hydraulic pump 51. Oil is supplied to one chamber of the boom drive hydraulic cylinder 105 through oil passages 95 and 78, and further, hydraulic oil from the second hydraulic pump 52 of the second circuit portion 56 passes through oil passages 66a, 90, and 78. The boom drive hydraulic cylinder 105 is supplied to the other chamber. On the other hand, hydraulic fluid in one chamber of the boom drive hydraulic cylinder 105 is discharged to the reservoir tank 70 via the oil passages 79, 91, 66 b or the oil passages 79, 69. As a result, the boom 103 is rotated upward as indicated by an arrow a in FIG. 8 while the boom driving hydraulic cylinder 105 is extended.
[0050]
Further, in order to maintain the current state of the boom drive hydraulic cylinder 105, the pilot hydraulic pressure is appropriately applied to the first boom control valve 59 and the second boom control valve 65 so that the first boom control valve 59, The position of each spool of the two-boom control valve 65 may be set to the neutral position (hydraulic supply / discharge path blocking position). As a result, the supply and discharge of the hydraulic oil in each oil chamber of the boom drive hydraulic cylinder 105 is stopped, and the boom 103 is held at the current position.
[0051]
Further, for example, to operate the stick 104, the operation member 54 in the operation operation chamber 101 is operated, and the pilot hydraulic pressure P from the pilot pump 83 acts on the stick control valves 60 and 64 through a pilot oil passage (not shown). Thus, the stick control valves 60 and 64 are driven to required positions. As a result, the hydraulic oil in the stick driving hydraulic cylinder 106 is supplied and discharged, and the cylinders 105 and 106 are driven to extend and contract to a required length, whereby the stick 104 is operated.
[0052]
For example, in order to rotate the stick 104 inward (stick-in), the stick driving hydraulic cylinder 106 may be extended. In this case, the pilot hydraulic pressure is applied to the second stick control valve 60 through the pilot oil passage. As a result, the spool position of the second stick control valve 60 becomes the stick inner rotation position (stick-in position), and the hydraulic oil from the first hydraulic pump 51 of the first circuit section 55 passes through the oil passages 61 and 67. Then, it is supplied to one chamber of the stick driving hydraulic cylinder 106. On the other hand, hydraulic oil in the other chamber of the stick driving hydraulic cylinder 106 is discharged to the reservoir tank 70 through the oil passages 68 and 69. Accordingly, the stick 104 is rotated inward as indicated by an arrow d in FIG. 8 while the stick driving hydraulic cylinder 106 is extended.
[0053]
Conversely, to rotate the stick 104 outward (stick out), the stick driving hydraulic cylinder 106 may be contracted. In this case, the pilot hydraulic pressure is applied to the second stick control valve 60 through the pilot oil passage. As a result, the spool position of the second stick control valve 60 becomes the stick outer rotation position (stick-out position), and hydraulic oil from the first hydraulic pump 51 of the first circuit section 55 passes through the oil passages 61 and 68. Then, it is supplied to the other chamber of the stick driving hydraulic cylinder 106. On the other hand, hydraulic oil in one chamber of the stick driving hydraulic cylinder 106 is discharged to the reservoir tank 70 through the oil passages 67 and 69. As a result, the stick 104 is rotated outward as indicated by an arrow c in FIG. 8 while the stick driving hydraulic cylinder 106 contracts.
[0054]
Further, in order to maintain the current state of the stick driving hydraulic cylinder 106, pilot hydraulic pressure is appropriately applied to the second stick control valve 60, and the position of each spool of the second stick control valve 60 is set to the neutral position (hydraulic pressure). The supply / exhaust passage blocking position may be set. As a result, the supply and discharge of hydraulic oil in each oil chamber of the stick driving hydraulic cylinder 106 is stopped, and the stick 104 is held at the current position.
[0055]
Further, for example, in order to operate the bucket 108, the bucket operating member 54c in the operation operation chamber 101 is operated, and the pilot hydraulic pressure P from the pilot pump 83 acts on the bucket control valve 58 through a pilot oil passage (not shown). Then, the bucket control valve 58 is moved to a required position. As a result, the hydraulic oil in the bucket driving hydraulic cylinder 107 is adjusted to be supplied and discharged, and these cylinders 107 are extended and contracted to a required length, whereby the bucket 108 is operated.
[0056]
For example, in order to rotate the bucket 108 inward (bucket in), the bucket driving hydraulic cylinder 107 may be extended. In this case, the pilot hydraulic pressure is applied to the bucket control valve 58 through the pilot oil passage. As a result, the spool position of the bucket control valve 58 becomes the bucket inner rotation position (bucket in position), and the hydraulic oil from the first hydraulic pump 51 of the first circuit portion 55 passes through the oil passages 61 and 92. It is supplied to one chamber of the hydraulic cylinder 107 for driving the bucket. On the other hand, hydraulic oil in the other chamber of the bucket driving hydraulic cylinder 107 is discharged to the reservoir tank 70 through the oil passages 93 and 69. Accordingly, the bucket 108 is rotated inward as indicated by an arrow f in FIG. 8 while the bucket driving hydraulic cylinder 107 is extended.
[0057]
Conversely, to rotate the bucket 108 outward (bucket open), the bucket drive hydraulic cylinder 107 may be contracted. In this case, the pilot hydraulic pressure is applied to the bucket control valve 58 through the pilot oil passage. As a result, the spool position of the bucket control valve 58 becomes the bucket outer rotation position (bucket open position), and the hydraulic oil from the first hydraulic pump 51 of the first circuit portion 55 passes through the oil passages 94 and 93, It is supplied to the other chamber of the bucket driving hydraulic cylinder 107. On the other hand, hydraulic fluid in one chamber of the bucket driving hydraulic cylinder 107 is discharged to the reservoir tank 70 through the oil passages 92 and 69. As a result, the bucket 108 is rotated outward as indicated by an arrow e in FIG. 8 while the bucket driving hydraulic cylinder 107 contracts.
[0058]
Further, in order to maintain the current state of the bucket drive hydraulic cylinder 107, the pilot hydraulic pressure is appropriately applied to the bucket control valve 58, and the position of the spool of the bucket control valve 58 is set to the neutral position (hydraulic supply / drain passage blocking position). ). As a result, the supply and discharge of the hydraulic oil in the oil chamber of the bucket driving hydraulic cylinder 107 is stopped, and the bucket 108 is held at the current position.
[0059]
By the way, various sensors are attached to the construction machine configured as described above, and detection signals from the respective sensors are sent to the controller 1 described later.
For example, an engine speed sensor 71 is attached to the engine 50 that drives the hydraulic pumps 51 and 52, and a detection signal from the engine speed sensor 71 is sent to the controller 1 described later. The controller 1 performs feedback control so that the actual engine speed becomes the target engine speed set by the operator using the engine speed setting dial.
[0060]
Further, on the discharge side of the first hydraulic pump 51 of the first circuit unit 55 and the second hydraulic pump 52 of the second circuit unit 56, pressure sensors (P / S-P1) 72, A pressure sensor (P / S-P2) 73 is provided, and detection signals from these pressure sensors 72 and 73 are sent to the controller 1 described later.
[0061]
Further, pressure sensors (P / S-N1) are respectively provided downstream of the control valves 57 to 60 of the oil passage 61 of the first circuit portion 55 and the control valves 62 to 65 of the oil passage 66 of the second circuit portion 56. ) 74 and pressure sensor (P / S-N2) 75 are provided, and detection signals from these pressure sensors 74 and 75 are sent to the controller 1 described later.
[0062]
Further, a pressure sensor (P / S-BMd) 80 is provided in an oil passage for supplying and discharging hydraulic oil to and from the boom driving hydraulic cylinder 105, and the rod of the boom driving hydraulic cylinder 105 is provided by the pressure sensor 80. The side pressure (load pressure) can be detected. And the detection signal from this pressure sensor 80 is sent to the controller 1 mentioned later.
[0063]
And in this embodiment, the controller 1 is provided in order to control the construction machine comprised as mentioned above.
The controller 1 controls the first hydraulic pump 51, the second hydraulic pump 52, the regenerative valves 76, 77, and the respective controls based on the detection signals from the sensors 71 to 75, 80 and the electrical signals from the operation member 54. By outputting an operation signal to the valves 57 to 60 and 62 to 65, the tilt angle control of the first hydraulic pump 51 and the second hydraulic pump 52, the position control of each control valve 57 to 60, 62 to 65, and each regeneration The position of the valves 76 and 77 is controlled.
[0064]
Among these, the tilt angle control of the first hydraulic pump 51 and the second hydraulic pump 52 by the controller 1 is performed on the downstream side of the bypass passage 61 b of the first circuit portion 55 and the downstream side of the bypass passage 66 c of the second circuit portion 56. The negative flow control is performed based on detection signals from the respective pressure sensors 74 and 75 provided. Since negative flow control is performed based on the pressure detected by the pressure sensors 74 and 75, the pressure detected by the pressure sensors 74 and 75 is also referred to as a negative control pressure.
[0065]
Here, negative flow control (electronic negative flow control system) refers to pump flow control with negative characteristics that reduces the pump discharge flow rate when the pressure on the downstream side of the bypass passages 61b and 66c increases.
Here, the negative flow control is a flow control in which the pump discharge flow rate is controlled in accordance with the operation amount of each operation member 54, that is, the negative control pressure, and the pump discharge flow rate in accordance with the load pressure applied to the actuator, that is, the pump discharge pressure. It is divided into horsepower control to be controlled.
[0066]
Among these, the flow rate control can control the speed of the actuator (each cylinder) within the allowable horsepower. That is, the pump discharge flow rate can be controlled in accordance with the operation amount of each operation member 54, that is, the negative control pressure, and thereby the speed of the actuator can be controlled.
By the way, when each operation member 54 is fully operated and the pump discharge flow rate becomes maximum and the actuator speed becomes maximum, the pump discharge flow rate (that is, the actuator speed) is determined by the following equation.
[0067]
Pump discharge flow rate Q = allowable horsepower W / pump discharge pressure P
In this state, if the load pressure applied to the actuator varies, the pump discharge pressure P also varies, and the pump discharge flow rate Q also varies from the above equation. Therefore, the actuator speed also varies.
As described above, the pump discharge flow rate Q is not controlled according to the operation amount of each operation member 54, but is controlled according to the load pressure applied to the actuator, that is, the pump discharge pressure P. The control in a state depending on the allowable horsepower W of the engine 50 that drives the first hydraulic pump 51 and the second hydraulic pump 52 is called horsepower control.
[0068]
When such horsepower control is performed, even if the operator fully operates each operation member 54 and requests the maximum speed of the actuator, the actual speed of the actuator is determined by the magnitude of the load pressure. In this case, the horsepower of the engine 50 is an allowable maximum value.
For example, when operating a plurality of actuators simultaneously, even if each operation member 54 is not fully operated, hydraulic oil is supplied to each actuator, the negative control pressure is reduced, and the required flow rate is reduced. When the allowable flow rate determined by the allowable horsepower is exceeded, the pump tilt angle control is performed so that the allowable flow rate in the horsepower control is obtained.
[0069]
By the way, when the operation member 54 is in the neutral position, that is, when the operator is not operating the operation member 54, the work machine 118 does not work at all, and it is not necessary to drive the actuator. Desirably, the pump discharge flow rate should be zero.
For this reason, in this embodiment, each control valve 57-60, 62-65 is an open center (arranged so that the bypass passages 61b, 66c are open at the spool neutral position), and the operation member 54 is neutral. In the case of the position, the hydraulic oil supplied from the hydraulic pumps 51 and 52 returns to the reservoir tank 70 through the bypass passages 61b and 66c.
[0070]
Thus, when the operation member 54 is in the neutral position, the pressure immediately upstream of the throttles 81 and 82 interposed downstream of the bypass passages 61b and 66c increases, and the variable displacement hydraulic pump 51 is controlled by negative flow control. , 52 is controlled so that the pump discharge flow rate decreases.
On the other hand, when the operation member 54 is operated, an amount of hydraulic oil corresponding to the operation amount is supplied to each actuator (cylinder, etc.), and the remaining hydraulic oil returns to the reservoir tank 70 through the bypass passages 61b and 66c. It is like that.
[0071]
Further, as described above, the restrictors (orifices) 81 and 82 are provided on the downstream side of the bypass passages 61b and 66c. Pressure sensors 74 and 75 are interposed in the bypass passages 61 b and 66 c immediately upstream of the throttles 81 and 82, and the pressure immediately upstream of the throttles 81 and 82 detected by these pressure sensors 74 and 75. The tilt angle control of the hydraulic pumps 51 and 52 is performed based on the above.
[0072]
When the operator operates the operation member 54, the control valves 57 to 60 and 62 to 65 are moved according to the operation amount of the operation member 54, the bypass passages 61b and 66c are throttled, and the operation flows through the bypass passages 61b and 66c. Although the flow rate of the oil is reduced, the diameters of the throttles 81 and 82 are constant, so that the pressure immediately upstream of the throttles 81 and 82, that is, the pressure detected by the pressure sensors 74 and 75 is decreased by the reduced flow rate. Then, the tilt angle control of the variable displacement hydraulic pumps 51 and 52 is performed so that the pump discharge flow rate increases in accordance with the reduced pressure.
[0073]
This means that the pump discharge flow rate is controlled to increase according to the operator's request, that is, the operation amount of the operation member 54 by the operator. This is because the operator operates the operation member 54 to operate the hydraulic pump 51. , 52 can control the pump discharge flow rate to control the speed of the actuator (each cylinder).
[0074]
Here, basic pump tilt angle control in the negative flow control by the controller 1 will be described.
That is, the controller 1 operates the hydraulic pressure (negative control pressure) P detected by the pressure sensors 74 and 75. _N1 , P _N2 Is read, negative control pressure P _N And required flow rate Q _N The negative control pressure P read from the map as shown in FIG. _N1 , P _N2 Required flow rate Q corresponding to _N1 , Q _N2 (Specifically, required flow rate Q _N1 , Q _N2 Equivalent to the pump tilt angle V _N1 , V _N2 ) Is set. The required flow rate refers to a flow rate required in negative flow control. In FIG. 4, the negative control pressure P _N1 Required flow rate Q corresponding to _N1 (Specifically, required flow rate Q _N1 , Equivalent to the pump tilt angle V _N1 Only).
[0075]
On the other hand, the controller 1 uses the pump discharge pressure P detected by the pressure sensors 72 and 73. _P1 , P _P2 Is read and the pump discharge pressure P _P And allowable flow rate Q _P From the map as shown in FIG. _P1 , P _P2 Allowable flow rate Q corresponding to _P1 , Q _P2 (Specifically, allowable flow rate Q _P1 , Q _P2 Equivalent to the pump tilt angle V _P1 , V _P2 ) Is set. The allowable flow rate is a pump discharge flow rate corresponding to the allowable horsepower of the engine 50 that drives the first hydraulic pump 51 and the second hydraulic pump 52. In FIG. 5, the pump discharge pressure P _P1 Allowable flow rate Q corresponding to _P1 (Specifically, allowable flow rate Q _P1 Equivalent to the pump tilt angle V _P1 Only).
[0076]
And the controller 1 is the above-mentioned required flow rate Q. _N1 , Q _N2 And allowable flow rate Q _P1 , Q _P2 And the smaller pump flow rate (required flow rate Q _N1 , Q _N2 Or allowable flow rate Q _P1 , Q _P2 ) So that the pump tilt angle (pump tilt angle V _N1 , V _N2 Or pump tilt angle V _P1 , V _P2 ) And is output to the first hydraulic pump 51 and the second hydraulic pump 52 as a tilt angle control signal.
[0077]
Next, the basic pump tilt angle control operation in the negative flow control by the controller 1 will be described with reference to the flowchart of FIG.
That is, first, in step S10, the negative control pressure P _N1 , P _N2 And at step S20 the pump discharge pressure P _P1 , P _P2 Is read.
[0078]
Next, the negative control pressure P read in step S10 in step S30 _N1 , P _N2 Required flow rate Q corresponding to _N1 , Q _N2 4 is calculated from the map of FIG. 4 and the pump discharge pressure P read in step S20 in step 40. _P1 , P _P2 Allowable flow rate Q corresponding to _P1 , Q _P2 Is calculated from the map of FIG.
In step S50, the required flow rate Q _N1 , Q _N2 Is allowable flow rate Q _P1 , Q _P2 Or less, and as a result of this determination, the required flow rate Q _N1 , Q _N2 Is allowable flow rate Q _P1 , Q _P2 When it is determined that the flow rate is smaller than the required flow rate Q, the process proceeds to step S60. _N1 , Q _N2 Set as the pump flow rate and return. As a result, the tilt angles of the first hydraulic pump 51 and the second hydraulic pump 52 become the required flow rate Q. _N1 , Q _N2 The tilt angle is set according to the angle.
[0079]
On the other hand, required flow rate Q _N1 , Q _N2 Is allowable flow rate Q _P1 , Q _P2 If it is determined that the flow rate is equal to or greater than the allowable flow rate Q, the process proceeds to step S70. _P1 , Q _P2 Set as the pump flow rate and return. As a result, the tilt angles of the first hydraulic pump 51 and the second hydraulic pump 52 become the allowable flow rate Q. _P1 , Q _P2 The tilt angle is set according to the angle.
The construction machine control device according to the present embodiment is configured as described above, and various controls are performed by the controller 1. In the present embodiment, the boom-up fine operation, the stick-in fine operation and the bucket are performed during the so-called leveling work. When the in fine operation is performed simultaneously, pump flow rate control different from the pump flow rate control in the normal negative flow control is performed.
[0080]
Next, the pump flow rate control in the case where the boom-up fine operation, the stick-in fine operation, and the bucket-in fine operation are performed at the same time during the leveling work, which is a feature of the construction machine control device according to the present embodiment, will be described.
Here, FIG. 1 is a control block diagram for explaining the pump flow rate control by the construction machine control device according to the present embodiment.
[0081]
In the present embodiment, as shown in FIG. 1, the controller 1 includes a boom-up fine operation determining means (boom fine operation determining means) 2, a stick-in fine operation determining means (stick fine operation determining means) 3, a bucket-in A fine operation determination means (bucket fine operation determination means) 4 and a pump tilt angle control means 5 are provided.
Of these, the boom-up fine operation determining means 2 determines whether or not a boom-up fine operation has been performed based on an electrical signal corresponding to the amount of operation of the boom operation member 54a, and the result of the determination is pump tilted. A signal is output to the angle control means 5.
[0082]
The stick-in fine operation determining means 3 determines whether or not the stick-in fine operation has been performed based on an electrical signal corresponding to the operation amount of the stick operation member 54b, and the determination result is used as the pump tilt angle control means. 5 outputs a signal.
The bucket-in fine operation determination means 4 determines whether or not the bucket-in fine operation has been performed based on an electrical signal corresponding to the operation amount of the bucket operation member 54c, and the determination result is used as the pump tilt angle control means. 5 outputs a signal.
[0083]
The pump tilt angle control unit 5 is configured to perform boom-up fine operation, stick-in fine operation, and bucket-in fine operation based on signals from the boom-up fine operation determination unit 2, the stick-in fine operation determination unit 3, and the bucket-in fine operation determination unit 4. When it is determined that the fine operations are performed simultaneously, an electric signal corresponding to the operation amount of the boom operation member 54a, the stick operation member 54b, and the bucket operation member 54c so that the optimum pump flow rate in this operation pattern is obtained. Based on this, the pump tilt angle control of the hydraulic pumps 51 and 52 is performed.
[0084]
Specifically, in the present embodiment, the pump tilt angle control means 5 controls the tilt angles of the hydraulic pumps 51 and 52 as follows.
The pump tilt angle control means 5 basically performs tilt angle control of the hydraulic pumps 51 and 52 by negative flow control.
In this negative flow control, when the boom operation member 54a, the stick operation member 54b, and the bucket operation member 54c are operated, the control valves 58 to 60 are controlled in accordance with the operation amounts of the operation members 54a, 54b, and 54c. , 64, 65 are controlled, and hydraulic oil is supplied to the boom driving hydraulic cylinder 105, the stick driving hydraulic cylinder 106, and the bucket driving hydraulic cylinder 107, so that each of these control valves 58-60, 64 is controlled. , 65 (the pressure of the hydraulic oil in the bypass passages 61b and 66c) is reduced, and this pressure is detected by the pressure sensors 74 and 75 and used in negative flow control. The tilt angles of the hydraulic pumps 51 and 52 are controlled so as to increase.
[0085]
For this reason, the boom-up fine operation, the stick-in fine operation, and the bucket-in fine operation are performed at the same time. Will be performed.
Therefore, in this embodiment, the pump tilt angle control means 5 determines that the boom-up fine operation, the stick-in fine operation, and the bucket-in fine operation are performed at the same time, the boom operation member 54a, the stick operation member. Based on the electrical signals from 54b and the bucket operating member 54c, the hydraulic pumps 51 and 52 are configured so that the pump discharge flow rate is reduced according to the operation amount of the boom operating member 54a, the stick operating member 54b and the bucket operating member 54c. The pump tilt angle control is performed.
[0086]
When the pump tilt angle control of the hydraulic pumps 51 and 52 is performed in this way, for example, the boost pressure (the differential pressure between the pump discharge pressure of the hydraulic pumps 51 and 52 and the load pressure) is a predetermined pressure (about 100 kgf / cm). ² ) For this reason, the pump discharge pressure is a predetermined pressure (about 100 kgf / cm than the load pressure). ² The pump tilt angle control may be performed based on electric signals from the boom operation member 54a, the stick operation member 54b, and the bucket operation member 54c so as to be higher.
[0087]
In order to ensure the simultaneous operability of the boom 103, the stick 104, and the bucket 108, the pressure of the hydraulic oil discharged from the hydraulic pumps 51, 52 is the maximum pressure among the operating pressures of these working machines 118. (Maximum pressure value) must be set. For this reason, also in the control balance of the negative flow control described above, the pump discharge flow rate is slightly increased from the total flow rate of the hydraulic oil supplied to each cylinder 105 to 107, and the surplus pump discharge flow rate is reduced by the bypass passage restriction of each control valve. It is set to increase the pressure by squeezing.
[0088]
On the other hand, the pump tilt angle control means 5 is configured to perform boom-up fine operation, stick-in fine operation and stick-in fine operation based on signals from the boom-up fine operation determination means 2, the stick-in fine operation determination means 3, and the bucket-in fine operation determination means 4. When it is determined that the bucket-in fine operation is not performed at the same time, it is determined that the operation is one of the boom 103, the stick 104, and the bucket 108 without fine operation. The pump flow rate control of the hydraulic pumps 51 and 52 is performed so as to obtain a pump flow rate.
[0089]
Here, the normal negative flow control means that, as described above, the control valves 57 to 60 and 62 to 65 are operated according to the operation amounts of the operation members 54, and the hydraulic oil in the bypass oil passages 61b and 66c is operated. The pressure (negative control pressure) generated when the flow rate changes is detected by pressure sensors 74 and 75, and the pump flow rate is controlled by controlling the pump tilt angle of the hydraulic pumps 51 and 52. In this case, pump tilt angle control based on electric signals from the boom operation member 54a, the stick operation member 54b, and the bucket operation member 54c is not performed.
[0090]
Thus, when the pump tilt angle control of the hydraulic pumps 51 and 52 is performed, for example, the boost pressure is a predetermined pressure (about 150 to 200 kgf / cm ² ) For this reason, the pump discharge pressure is higher than the load pressure by a predetermined pressure (about 150 to 200 kgf / cm ² The pump tilt angle can be controlled to be higher.
Here, in the negative flow control, the required pump flow rate varies depending on the difference in lever pattern and the amount of operation.
[0091]
For example, as a difference in the operation pattern of the operation member 54, when the boom-up and the stick-out are linked, the boost pressure is a predetermined pressure (about 200 kgf / cm ² ) And when the boom-up and bucket-out are linked, the boost pressure is a predetermined pressure (about 150 kgf / cm ² The pump flow rate should be such that
[0092]
On the other hand, differences in the operation amount of the operation member 54 include, for example, a boom-up fine operation, a stick-in operation (operation of about 50 to 100% with respect to the total operation amount), and a bucket-in operation (about about the total operation amount). When operation of about 50 to 100% is performed, this corresponds to excavation work using the stick 104 and the bucket 108, and the pump discharge pressure is a pressure balanced with the excavation load. In this case, since the boost pressure is not generated, the pump flow rate corresponding to the operation amount of the operation member 54 is supplied to ensure the productivity.
[0093]
The construction machine control device according to the present embodiment is configured as described above, and operates as shown in the flowchart of FIG. 7 in order to perform optimal pump flow rate control during so-called leveling work.
That is, in step A10, an electric signal from each operation member 54 is read, and the process proceeds to step A20.
[0094]
In step A20, it is determined by the boom-up fine operation determination means 2 whether or not a boom-up fine operation has been performed based on the operation amount of the boom operation member 54a.
As a result of the determination, if it is determined that the boom-up fine operation has been performed, the process proceeds to step A30, where the stick-in fine operation determination means 3 performs the stick-in fine operation based on the operation amount of the stick operation member 54b. It is determined whether or not it has been.
[0095]
As a result of the determination, if it is determined that the stick-in fine operation has been performed, the process proceeds to step A40, and the bucket-in fine operation determination means 4 further performs the bucket-in fine operation based on the operation amount of the bucket operation member 54c. When it is determined whether or not the bucket-in fine operation has been performed, the process proceeds to step A50, where the boom-up fine operation, the stick-in fine operation, and the bucket-in fine operation are performed simultaneously. Since it is considered to be during so-called leveling work, the boom operation member 54a and the stick operation are controlled by the pump tilt angle control means 5 so that the optimum pump flow rate is obtained during leveling work (boom, stick, bucket fine operation). The pump tilt angle control is performed according to the operation amount of the member 54b and the bucket operation member 54c, To turn.
[0096]
On the other hand, if it is determined in step A20 that the boom-up fine operation determining means 2 has not performed the boom-up fine operation determining means 2, it is determined in step A30 that the stick-in fine operation determining means 3 has not been performed. If it is determined in step A40 that the bucket-in fine operation determining means 4 determines that the bucket-in fine operation has not been performed, it is determined that the ground leveling work is not being performed in any case, and the process proceeds to step A60. Then, the pump tilt angle control is performed so as to obtain the optimum pump flow rate in the normal negative flow control, and the process returns.
[0097]
Here, Table 1 shown below shows the measurement results of fuel consumption when optimal pump flow rate control is performed during leveling work. Table 1 shows the measurement results when the leveling operation (leveling operation) is performed 10 cycles.
[0098]
[Table 1]

As shown in Table 1, when the optimum pump flow rate control is performed in the present embodiment, it can be seen that the fuel efficiency during the leveling work can be improved by about 25% compared to the conventional pump flow rate control. Note that the fuel consumption when the bucket operation member 54c and the stick operation member 54b are fully operated is almost the same as in the conventional case.
[0099]
Therefore, according to the present embodiment, the boom-up fine operation, the stick-in fine operation, and the bucket-in fine operation are simultaneously performed based on the operation amounts of the boom operation member 54a, the stick operation member 54b, and the bucket operation member 54c. In this case, it is determined that the work is so-called leveling work, and the tilt angle control of the hydraulic pumps 51 and 52 is performed so that the optimum pump flow rate is obtained in this leveling work. There is an advantage that loss can be suppressed and fuel consumption can be improved.
[0100]
Further, the leveling work is performed when the boom-up fine operation, the stick-in fine operation, and the bucket-in fine operation are simultaneously performed based on the operation amounts of the boom operation member 54a, the stick operation member 54b, and the bucket operation member 54c. In order to control the tilt angle of the hydraulic pumps 51 and 52 in accordance with the operation amounts of the boom operation member 54a, the stick operation member 54b, and the bucket operation member 54c so that the pump discharge pressure does not increase excessively. In other words, since the tilt angle of the hydraulic pumps 51 and 52 is controlled so as to reduce the pump discharge flow rate, the output loss of the engine 50 that drives the hydraulic pumps 51 and 52 can be suppressed, and the fuel consumption can be improved. There is an advantage that you can.
[0101]
In the above-described embodiment, the case where the boom-up fine operation, the stick-in fine operation, and the bucket-in fine operation are performed has been described. However, the present invention is not limited to this, and the boom-down fine operation (boom fine operation), stick The present invention can be similarly applied even when an out fine operation (stick fine operation) and a bucket open fine operation (bucket fine operation) are performed.
[0102]
In this case, the boom fine operation determination means 2 is configured to determine whether the boom down fine operation has been performed based on the operation amount of the boom operation member 54a, and the stick fine operation determination means 3 is the stick operation member. It is configured to determine whether or not the stick-out fine operation has been performed based on the operation amount of 54b, and the bucket fine operation determination means 4 performs the bucket open fine operation based on the operation of the bucket operation member 54c. It is comprised as what determines. Then, the pump tilt angle control means 5 performs tilt angle control of the hydraulic pumps 51 and 52 based on the determination results of the boom fine operation determination means 2, the stick fine operation determination means 3 and the bucket fine operation determination means 4. become.
[0104]
【The invention's effect】
As described in detail above, according to the construction machine control device of the present invention, the boom-up operation is performed based on the operation amounts of the boom operation member, the stick operation member, and the bucket operation member. In order to perform the tilt angle control of the hydraulic pump so as to determine the so-called leveling work when the fine operation, the stick-in fine operation, and the bucket-in fine operation are performed at the same time, and to achieve the optimum pump flow rate in this leveling work There is an advantage that the output loss of the engine that drives the hydraulic pump can be suppressed, and the fuel consumption can be improved.
[0105]
According to the construction machine control device of the present invention, the boom-up fine operation, the stick-in fine operation, and the bucket based on the operation amounts of the boom operation member, the stick operation member, and the bucket operation member. It is determined that the work is leveling when the in-fine operation is performed at the same time, and the pump discharge is performed according to the operation amount of the boom operation member, stick operation member, and bucket operation member so that the pump discharge pressure does not increase excessively. Since the tilt angle of the hydraulic pump is controlled so as to reduce the flow rate, there is an advantage that the output loss of the engine that drives the hydraulic pump can be suppressed and the fuel consumption can be improved.
[Brief description of the drawings]
FIG. 1 is a control block diagram for explaining tilt angle control of a hydraulic pump in a construction machine control device according to an embodiment of the present invention.
FIG. 2 is an overall configuration diagram of a construction machine control device according to an embodiment of the present invention.
FIG. 3 is a schematic diagram for explaining a control valve of the control device for the construction machine according to the embodiment of the present invention.
FIG. 4 is a diagram showing a relationship between a required flow rate of negative flow control and a negative control pressure in the control device for a construction machine according to one embodiment of the present invention.
FIG. 5 is a diagram showing a relationship between an allowable flow rate of negative flow control and a pump discharge pressure in the construction machine control device according to the embodiment of the present invention.
FIG. 6 is a flowchart for explaining negative flow control in the construction machine control device according to the embodiment of the present invention;
FIG. 7 is a flowchart for explaining pump tilt angle control in the construction machine control device according to the embodiment of the present invention;
FIG. 8 is a schematic perspective view showing a conventional construction machine.
[Explanation of symbols]
1 Controller (control means)
2 Boom-up fine operation determination means (boom fine operation determination means)
3 Stick-in fine operation determination means (stick fine operation determination means)
4 Bucket-in fine operation determination means (bucket fine operation determination means)
5 Pump tilt angle control means
51 1st hydraulic pump
52 Second hydraulic pump
54 Operating members
54a Operation member for boom
54b Operation member for stick
54c Operation member for bucket
72, 73, 74, 75 Pressure sensor
103 boom
104 stick
108 buckets

Claims (4)

A hydraulic pump that discharges hydraulic oil in the tank;
A plurality of operating members adapted to output an electrical signal according to the operation amount that by the operator,
Control means for controlling the discharge flow rate from the hydraulic pump,
The control means
Boom fine operation determination means for determining whether a boom fine operation has been performed based on an electric signal from the boom operation member among the plurality of operation members;
A stick fine operation determination means for determining whether a stick fine operation has been performed based on an electrical signal from a stick operation member among the plurality of operation members;
Bucket fine operation determination means for determining whether a bucket fine operation has been performed based on an electrical signal from the bucket operation member among the plurality of operation members;
When the boom fine operation determining means, the stick fine operation determining means and the bucket fine operation determining means determine that the boom fine operation, the stick fine operation and the bucket fine operation are performed simultaneously, the boom operation member, While the tilt angle control of the hydraulic pump is performed according to the operation amount of the stick operation member and the bucket operation member, it is determined that any one of the boom fine operation, the stick fine operation, and the bucket fine operation is not performed. And a pump tilt angle control means for controlling the tilt angle of the hydraulic pump by negative flow control . A hydraulic pump that discharges hydraulic oil in the tank;
A pressure sensor provided on the downstream side of a bypass passage communicating the hydraulic pump and the tank in order to supply and discharge hydraulic oil to and from the hydraulic actuator;
A plurality of operation members configured to output an electrical signal according to an operation amount by an operator;
Control means for controlling the discharge flow rate from the hydraulic pump,
The control means
A boom fine operation determination means for determining whether a boom fine operation has been performed based on an electric signal from a boom operation member among the plurality of operation members;
A stick fine operation determination means for determining whether a stick fine operation has been performed based on an electric signal from a stick operation member among the plurality of operation members;
Bucket fine operation determination means for determining whether a bucket fine operation has been performed based on an electrical signal from the bucket operation member among the plurality of operation members;
When the boom fine operation determining means, the stick fine operation determining means, and the bucket fine operation determining means determine that the boom fine operation, the stick fine operation, and the bucket fine operation are performed simultaneously, the boom operation member, While the tilt angle control of the hydraulic pump is performed according to the operation amount of the stick operation member and the bucket operation member, it is determined that any one of the boom fine operation, the stick fine operation, and the bucket fine operation is not performed. And a pump tilt angle control means for controlling the tilt angle of the hydraulic pump based on a detection signal from the pressure sensor. The boom fine operation determining means is configured to determine whether a boom up fine operation has been performed,
The stick fine operation determination means is configured to determine whether a stick-in fine operation has been performed,
The bucket fine operation determination means is configured to determine whether a bucket-in fine operation has been performed,
The pump tilt angle control means determines that boom-up fine operation, stick-in fine operation, and bucket-in fine operation are simultaneously performed by the boom fine operation determination means, the stick fine operation determination means, and the bucket fine operation determination means. the boom operating member when, and performs the tilt angle control of the hydraulic pump in accordance with the operation amount of the operation member and said bucket operation member for the stick, the construction of claim 1 or 2, wherein Machine control device. Determined that the pump tilting angle control means, the boom fine operation determination means, boom fine operation by the stick fine operation determination means and said bucket fine operation determination means, stick fine operation and bucket fine operation is performed at the same time If it is, characterized in that the discharge flow rate from the hydraulic pump performs the tilt angle control of the hydraulic pump as Ru reduced than the discharge flow rate from the hydraulic pump by the negative flow control, according to claim 1 Or the control apparatus of the construction machine of 3 .

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