JP6788733B2 - Work machine - Google Patents

Description

The present invention relates to a working machine.

In a work machine such as a hydraulic excavator, it is common practice to drive a hydraulic pump with a prime mover and drive a hydraulic actuator such as a hydraulic cylinder with pressure oil discharged from the hydraulic pump. The speed and operating direction of the hydraulic actuator are controlled by controlling the direction and flow rate of the pressure oil supplied from the hydraulic pump to the hydraulic actuator by a directional control valve that operates in conjunction with the operation lever device provided in the cab. ..

In recent years, there has been an increasing need for fuel efficiency of work machines from the viewpoint of energy saving and protection of the global environment, and the loss of the flow of hydraulic energy from the hydraulic pump to the hydraulic actuator is also minimized. Since hydraulic energy is the product of the pressure and volume of the pressure oil used, in order to reduce energy loss, the pressure loss from the discharge pressure of the pump to the inlet pressure of the hydraulic actuator, or the discharge flow rate of the hydraulic pump and the hydraulic actuator It is conceivable to reduce the flow rate loss, which is the difference between the inlet flow rates.

As a method of reducing the flow rate loss, for example, in the area of fine operation of the lever operation amount where a large flow rate is not required for the hydraulic actuator, the discharge flow rate of the hydraulic pump is reduced to reduce the unnecessary pump discharge flow rate. It is known to reduce the loss of bleed-off flow rate to be discarded. Further, as a means of further reducing the flow rate loss, for example, in Patent Document 1, the pump reference flow rate according to the lever operation amount is adjusted to the minimum necessary pump discharge flow rate according to the opening degree of the bleed-off valve. , A technique for minimizing pressure loss and bleed-off flow rate loss without deteriorating operability is disclosed.

Patent No. 5886976

However, the above-mentioned prior art has the following problems.

The response of the increase / decrease of the discharge flow rate in the variable volume hydraulic pump tends to be slower than the response of the directional control valve or the electronically controlled bleed-off valve. Therefore, it takes time for the discharge flow rate of the hydraulic pump to reach an appropriate discharge flow rate with respect to the opening degree of the directional control valve or the bleed-off valve, so that the discharge pressure of the hydraulic pump does not increase until it overcomes the load pressure of the hydraulic actuator. , There is a problem that the operation of the hydraulic actuator is delayed. In other words, when the operating lever is operated intermittently and quickly, the operating lever is returned before the pump flow rate has finished increasing, so the pump flow rate is smaller than in steady operation, and the operation of the hydraulic actuator is extremely deteriorated. Is a concern. In particular, when a solenoid valve generates a flow control signal pressure for a hydraulic pump, a sudden change in the pump control signal pressure due to a delay in controlling the solenoid valve or a decrease in signal pressure due to pressure loss when passing through the solenoid valve. Was not possible in some cases.

The present invention has been made in view of the above, and is an operation capable of achieving both reduction of pressure loss and flow rate loss by controlling the discharge flow rate of the hydraulic pump and responsiveness of the hydraulic actuator by intermittent sudden lever operation. The purpose is to provide a machine.

The present application includes a plurality of means for solving the above problems. For example, a variable displacement hydraulic pump driven by a prime mover and a plurality of driven members are rotatably connected to each other. An articulated front working machine, a plurality of hydraulic actuators driven by pressure oil discharged from the hydraulic pump to drive the plurality of driven members, and the plurality of hydraulic actuators from the hydraulic pump. A plurality of direction switching valves that control the direction and flow rate of the supplied pressure oil, a plurality of operating devices that control the plurality of direction switching valves, and an operating amount of at least one of the plurality of operating devices. One or more operation amount detection devices to be detected, and a regulator that controls the pump volume of the hydraulic pump based on a pump control signal generated according to the operation amount of at least one operation device among the plurality of operation devices. , At least one operation amount of the signal adjustment valve capable of adjusting the pump control signal input to the regulator and the operation amount detection device for detecting the operation amount of the operation device related to the generation of the pump control signal. The controller includes a controller that controls the signal adjusting valve based on the detection result of the amount of operation from the detection device, and the controller has a normal mode in which the pump control signal is adjusted by the signal adjusting valve and the signal adjusting valve. It is possible to switch to either the responsiveness priority mode in which the pump control signal is not adjusted.

According to the present invention, it is possible to achieve both reduction of pressure loss and flow rate loss by controlling the discharge flow rate of the hydraulic pump and responsiveness of the hydraulic actuator by intermittent sudden lever operation.

It is a side view which shows typically the appearance of the hydraulic excavator which is an example of the work machine which concerns on 1st Embodiment. It is a figure which shows typically the main part of the hydraulic circuit system which concerns on 1st Embodiment by extracting. It is a functional block diagram which shows the calculation content of the pump target volume in a controller. It is a functional block diagram which shows the detail of the processing content of a pump target volume calculation part. It is a flowchart explaining the processing content in the responsiveness priority mode switching part. It is a functional block diagram which shows the calculation content of the pump target volume in the controller of the modification of the 1st Embodiment. It is a figure which shows an example of the setting menu composition displayed on the monitor (display device) of the input / output device in the modification of the 1st Embodiment. It is a figure which shows an example of the valid / invalidity determination table for determining the possibility of switching to the responsiveness priority mode for each work mode in the modification of the 1st Embodiment. It is a figure which shows typically the main part of the hydraulic circuit system which concerns on 2nd Embodiment by extracting. It is a functional block diagram which shows the calculation content of the pump target volume in the controller of the 2nd Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present embodiment, as an example of the work machine, a hydraulic excavator having a bucket as a work tool at the tip of the front device (front work machine) will be described as an example, but the present invention will be described as a hydraulic excavator having an attachment other than the bucket. It is also possible to apply the invention.

<First Embodiment>
The first embodiment of the present invention will be described with reference to FIGS. 1 to 5.

FIG. 1 is a side view schematically showing the appearance of a hydraulic excavator which is an example of a work machine according to the present embodiment.

In FIG. 1, the hydraulic excavator 100 is an articulated front device (front) configured by connecting a plurality of driven members (boom 31, arm 33, bucket (working tool) 35) that rotate in each vertical direction. The work machine) 30 and the upper swivel body 20 and the lower traveling body 10 constituting the vehicle body are provided, and the upper swivel body 20 is provided so as to be rotatable with respect to the lower traveling body 10. The upper swivel body 20 is configured by arranging each member on a swivel frame 21 which is a base, and the swivel frame 21 constituting the upper swivel body 20 can swivel with respect to the lower traveling body 10. Further, the base end of the boom 31 of the front device 30 is rotatably supported by the front portion of the upper swing body 20 in a vertical direction, and one end of the arm 33 is an end portion (tip) different from the base end of the boom 31. The bucket 35 is rotatably supported in the vertical direction at the other end of the arm 33.

The lower traveling body 10 is composed of a pair of crawlers 11a (11b) hung around a pair of left and right crawler frames 12a (12b), and a traveling hydraulic motor 13a (13b) for driving the crawlers 11a (11b), respectively. ing. For each configuration of the lower traveling body 10, only one of the left and right pairs is illustrated and designated, and for the other configuration, only the reference numerals in parentheses are attached in the drawings and the illustration is omitted. To do.

The boom 31, arm 33, bucket 35, and lower traveling body 10 are driven by the boom cylinder 32, the arm cylinder 34, the bucket cylinder 36, and the left and right traveling hydraulic motors 13a (13b), which are hydraulic actuators, respectively. Further, the upper swivel body 20 is also driven by the swivel hydraulic motor 27, which is a hydraulic actuator, via the reduction mechanism 26, and swivels with respect to the lower traveling body 10.

On the swivel frame 21 constituting the upper swivel body 20, along with the engine 22 which is a prime mover, a boom cylinder 32, an arm cylinder 34, a bucket cylinder 36, a swivel hydraulic motor 27, left and right traveling hydraulic motors 13a (13b), etc. A hydraulic circuit system 40 for driving a hydraulic actuator is mounted.

FIG. 2 is a diagram schematically showing a main part of the hydraulic circuit system according to the present embodiment by extracting it. Note that, in FIG. 2, only the bucket cylinder 36 and its related configuration are shown as representatives of the plurality of hydraulic actuators, and the other hydraulic actuators and their related configurations are not shown for the sake of simplicity.

In FIG. 2, the hydraulic circuit system 40 includes a variable-volume hydraulic pump 41 driven by an engine 22, a fixed-volume pilot pump (pilot hydraulic source) 49, and a hydraulic oil tank which is a hydraulic oil supply source for the hydraulic pump. It is supplied from the hydraulic pump 41 to the hydraulic actuator (bucket cylinder) 36 via the discharge line L4 based on the operation pilot pressure (operation signal) guided by the pilot lines L1 and L2 from the operation lever device 52 for operating the bucket and the 48. A control valve (direction switching valve) 44 that controls the direction and flow rate of the hydraulic oil, and an operation pilot pressure sensor (operation) that detects the operation amount of the operation lever device 52 by detecting the operation pilot pressure of the pilot lines L1 and L2. Volume detection devices) SE1 and SE2, and a regulator 42 that controls the pump volume (tilt angle) of the hydraulic pump 41 based on the pilot pressure (pump control signal) generated in response to the operation of the operation lever device 52. Proportional electromagnetic valve 45 (signal adjustment valve) that can be adjusted by reducing the pressure of the pump control signal input from the lever device 52 to the regulator 42, and proportional based on the detection results of the operation amount from the operation pilot pressure sensors SE1 and SE2. It is roughly composed of a controller 60 that controls the electromagnetic valve 45. A relief valve 41a that defines an upper limit of the discharge pressure of the hydraulic pump 41 is installed in the discharge line L4 from the hydraulic pump 41.

The driver's cab 23 (cabinet: see FIG. 1) on which the operator is boarded is provided with a plurality of operation lever devices (operation devices) that output operation signals for operating the hydraulic actuators 27, 32, 34, and 36. .. Of these, the operation lever device 52 for bucket operation generates operation signals output to the pilot lines L1 and L2 based on the operation lever 52a tilted by the operator and the lever operation amount and operation direction of the operation lever 52a. It has an operation signal generation unit 52b to be operated. When the operation lever 52a is operated, the operation signal generation unit 52b operates one of a pair of pressure reducing valves (not shown) according to the operation direction and the operation amount, and uses the pilot primary pressure of the pilot pump 49 as the operation amount. The pressure is reduced to the corresponding pilot pressure, and the operation signal (operation pilot pressure) is output to either the pilot lines L1 and L2. On the pilot lines L1 and L2, the operation pilot pressure sensor (operation amount detection device) SE1 and 2 for detecting the operation amount of the operation lever 52a (hereinafter, also referred to as the operation amount of the operation lever device 52) by detecting the operation pilot pressure. SE2 is arranged, the operation signal of the bucket cloud by the operation lever 52a is detected by the operation pilot pressure sensor SE1, the operation signal of the bucket dump by the operation lever 52a is detected by the operation pilot pressure sensor SE2, and each is detected by the controller 60. Sent. The operating lever device may be of an electric signal system, and the tilting amount of the lever (that is, the lever operating amount) corresponding to the operating signal from the operating lever device 52 operated by the operator is electrically output to the controller 60. The pilot pressure for driving each of the hydraulic actuators 27, 32, 34, and 36 may be controlled by controlling the electromagnetic proportional valve or the like with the controller 60 based on the detected lever operation amount.

The operation of the bucket 35 is assigned to the operation lever device 52, and when the bucket cloud is operated by the operation lever device 52, the control valve 44 is moved to the right side in FIG. 2 (that is, shown in FIG. 2) according to the operation amount. The pressure oil discharged from the hydraulic pump 41 is supplied to the bottom chamber (bucket cylinder bottom chamber) 36a of the bucket cylinder 36 via the control valve 44, and the rod chamber (bucket cylinder) of the bucket cylinder 36 is supplied. The pressure oil of the rod chamber) 36b flows into the hydraulic oil tank 48 via the control valve 44, so that the bucket cylinder 36 expands and the bucket cloud operation is performed. Similarly, when the bucket dump is operated by the operation lever device 52, the control valve 44 is driven to the left side in FIG. 2 according to the operation amount, and the pressure oil discharged from the hydraulic pump 41 is passed through the control valve 44. While being supplied to the bucket cylinder rod chamber 36b, the pressure oil in the bucket cylinder bottom chamber 36a flows into the hydraulic oil tank 48 via the control valve 44, so that the bucket cylinder 36 is shortened and the bucket dump operation is performed. When the operation lever device 52 is not operated, the control valve 44 is in the neutral position, and the pressure oil discharged from the hydraulic pump 41 returns to the hydraulic oil tank 48 via the center bypass line L5.

A check valve 44a is provided on the upstream side (that is, the hydraulic pump 41 side) of the supply flow path of the control valve 44. The check valve 44a allows the supply of pressure oil to the hydraulic actuator 36 side only when the discharge pressure (pump pressure) of the hydraulic pump 41 is higher than the pressure (actuator pressure) on the hydraulic actuator 36 side, and the pump pressure becomes high. When the pressure is lower than the actuator pressure, the flow of pressure oil from the hydraulic actuator 36 side to the hydraulic pump 41 side is blocked.

The operating pilot pressures of the pilot lines L1 and L2 are guided to the shuttle valve 43, respectively, and the larger operating pilot pressure is selectively output to the pilot line L3 (hereinafter referred to as a pump control signal primary pressure). The primary pressure of the pump control signal output to the pilot line L3 is reduced by the proportional solenoid valve 45 and output to the regulator by 42 (hereinafter referred to as the secondary pressure of the pump control signal). The regulator 42 is a positive control system that increases the pump volume (discharge flow rate) of the hydraulic pump 41 as the input operating pilot pressure (pump control signal secondary pressure) increases.

The controller 60 calculates the pump target volume of the hydraulic pump 41 based on the detection results of the operation pilot pressure sensors SE1 and SE2, and controls the proportional solenoid valve 45 based on the pump target volume. That is, the proportional solenoid valve 45 changes the opening area based on the control signal from the controller 60, so that the pump control signal (operating pilot pressure) input to the regulator 42 via the shuttle valve 43 is a pump control signal. It is a signal adjustment valve that can be adjusted by reducing the pressure from the primary pressure to the pump control signal secondary pressure. The proportional solenoid valve 45 is held at the position shown in FIG. 2 (maximum opening area) when there is no pump control signal from the controller 60, and moves upward in FIG. 2 as the control signal increases to increase the opening area. Decrease. The proportional electromagnetic valve 45 reduces the pump control signal input to the regulator 42 to limit the discharge flow rate of the hydraulic pump in the region of fine operation of the lever operation amount so that the hydraulic actuator does not require a large flow rate. The loss of bleed-off flow rate is reduced by discarding unnecessary pump discharge flow rate to the tank.

FIG. 3 is a functional block diagram showing the calculation contents of the pump target volume in the controller.

In FIG. 3, the controller 60 includes a pump target volume calculation unit C1, a pump control signal pressure target value calculation unit C2, a responsiveness priority mode switching unit C3, a pump flow rate control proportional solenoid valve valid / invalid switching unit C4, and a proportional solenoid. A valve current calculation unit C5 is provided.

The pump target volume calculation unit C1 calculates the pump target volume based on the lever operation amount (operation pilot pressure) of the operation lever device 52 detected by the operation pilot pressure sensors SE1 and SE2 and a predetermined table.

The pump control signal pressure target value calculation unit C2 calculates the pump control signal secondary pressure target value based on the pump target volume calculated by the pump target volume calculation unit C1 and a predetermined table. The table used to calculate the pump control signal secondary pressure target value from the pump target volume is the change in the pump volume of the hydraulic pump 41 due to the pump control signal (pilot pressure) set hard by the positive control type regulator 42. Set from the characteristics.

The responsiveness priority mode switching unit C3 determines whether or not the operation requires the responsiveness of the bucket operation based on the lever operation amount of the operation lever device 52 detected by the operation pilot pressure sensors SE1 and SE2. If it is determined that the operation requires responsiveness, the operation mode is switched to the responsiveness priority mode, and if not, the operation mode is switched to the normal mode.

Here, the responsiveness priority mode is a case where the operation of tilting the operation lever device 52 in the bucket dump direction and the operation of returning the operation lever device 52 in the bucket dump direction are repeated in a short time, such as a gravel sowing operation using a bucket for excavation, or on the bottom surface. The operation lever device 52 is repeatedly tilted and returned in the bucket dump direction and the bucket cloud direction in a short time to vibrate the bucket, as in the sieving operation using a skeleton bucket (not shown) having a mesh-like hole. In such a case, in other words, it is an operation mode that can be switched in an operation that requires responsiveness, such as when the operation amount of the operation lever device 52 changes intermittently and frequently in a short time, and is responsiveness in the present embodiment. When the mode is switched to the priority mode, the opening area of the proportional solenoid valve 45 is widened to improve the responsiveness. Further, the normal mode is an operation mode that is switched at the time of operation other than the responsiveness priority mode, and when the normal mode is switched in the present embodiment, the opening area of the proportional solenoid valve 45 is narrowed and input to the regulator 42. By reducing the primary pressure of the pump control signal to the secondary pressure of the pump control signal, the pump volume of the hydraulic pump is reduced, and the loss of the bleed-off flow rate at which unnecessary pump discharge flow rate is discarded in the tank is reduced.

The pump flow control proportional electromagnetic valve enable / disable switching unit C4 is the calculation result of the pump control signal pressure target value calculation unit C2 (pump control signal secondary pressure target) according to the operation mode switched by the response priority mode switching unit C3. The handling of the value) is switched, and when the operation mode is switched to the normal mode, the output of the pump control signal pressure target value calculation unit C2 is used as it is in the subsequent processing block (proportional electromagnetic valve current calculation unit C5). When the operation mode is switched to the responsiveness priority mode, the pump control signal secondary pressure target value is replaced with the maximum pilot pressure (for example, 4 MPa) of the hydraulic circuit system 40 to replace the processing block in the subsequent stage (for example, 4 MPa). Output to the proportional electromagnetic valve current calculation unit C5).

The proportional solenoid valve current calculation unit C5 outputs a control signal of the proportional solenoid valve 45 based on the target pressure of the proportional solenoid valve 45 input from the pump flow control proportional solenoid valve valid / invalid switching unit C4 and a predetermined table. It calculates and outputs, and drives the proportional solenoid valve 45. That is, when the responsiveness priority mode switching unit C3 is switched to the normal mode, the pump control signal primary pressure becomes the pump control signal secondary pressure based on the calculation result of the pump control signal pressure target value calculation unit C2. The proportional solenoid valve 45 is driven so as to reduce the pressure, and when the operation mode is switched to the responsive priority mode, the proportional solenoid valve 45 is driven so that the pressure reduction in the proportional solenoid valve 45 becomes invalid.

FIG. 4 is a functional block diagram showing details of the processing contents of the pump target volume calculation unit.

In FIG. 4, the pump target volume calculation unit C1 determines the pump target volume of the hydraulic pump 41 based on the operation pilot pressure corresponding to the bucket cloud operation, that is, the detection result of the operation pilot pressure sensor SE1 and a predetermined table. Calculate the pump target volume of the hydraulic pump 41 based on the bucket cloud target volume calculation unit T1 to be calculated, the operation pilot pressure corresponding to the bucket dump operation, that is, the detection result of the operation pilot pressure sensor SE2, and a predetermined table. Of the calculation results of the bucket dump target volume calculation unit T2, the bucket cloud target volume calculation unit T1 and the bucket dump target volume calculation unit T2, the larger one is output as the calculation result of the pump target volume of the pump target volume calculation unit C1. It has a maximum value selection unit T3.

In the table set in the bucket cloud target volume calculation unit T1, for example, as shown in FIG. 4, the horizontal axis sets the input value (the operation amount on the bucket cloud side of the operation lever device 52), and the vertical axis sets the pump target volume. This is a graph-like table, and the pump target volume is set to increase as the operation amount on the bucket cloud side of the operation lever device 52 increases. In the table set in the bucket cloud target volume calculation unit T1, the target volume (shown by the solid line) of the hydraulic pump 41 is set so that the pressure loss and the flow rate loss are minimized according to the opening area of the control valve 44. The volume is set to be smaller than the reference volume (indicated by the dotted line) of the hydraulic pump 41. Here, the reference volume of the hydraulic pump 41 corresponds to the relationship between the pilot pressure (pump control signal) input to the regulator 42 and the pump volume.

Similarly, in the table set in the bucket dump target volume calculation unit T2, for example, as shown in FIG. 4, the horizontal axis is the input value (the operation amount on the bucket dump side of the operation lever device 52), and the vertical axis is the pump target. It is a graph-shaped table in which the volume is set, and the pump target volume is set to increase as the operation amount on the bucket dump side of the operation lever device 52 increases. In the table set in the bucket dump target volume calculation unit T2, the target volume (shown by the solid line) of the hydraulic pump 41 is set so as to minimize the pressure loss and the flow rate loss according to the opening area of the control valve 44. The volume is set to be smaller than the reference volume (indicated by the dotted line) of the hydraulic pump 41.

The maximum value selection unit T3 outputs the larger of the calculation results of the bucket cloud target volume calculation unit T1 and the bucket dump target volume calculation unit T2 as the calculation result of the pump target volume of the pump target volume calculation unit C1.

FIG. 5 is a flowchart illustrating the processing contents in the responsiveness priority mode switching unit.

In FIG. 5, the responsiveness priority mode switching unit C3 repeatedly performs the mode determination process (steps S100 to S161) at intervals of time Δt. That is, the time Δt is a cycle in which the execution of the mode determination process is repeated, and is a sampling cycle of the operation pilot pressure sensors SE1 and SE2. For example, a unit time (for example, 10 ms) of the internal calculation in the controller 60 is used.

The responsiveness priority mode switching unit C3 first detects the pilot pressure corresponding to the bucket operation at the time of the previous mode determination process (time t−Δt), that is, the previous operation pilot pressure sensors SE1 and SE2. It is determined whether or not the detection result (previous value) of is less than the predetermined threshold value PI_ON and the current detection result (current value) is equal to or more than the threshold value PI_ON (step S100). The threshold value PI_ON is a reference for determining whether or not the bucket 35 is operated (bucket cloud operation or bucket dump operation) by the operation lever device 52, and the detection results of the operation pilot pressure sensors SE1 and SE2 are threshold values. If it is less than PI_ON, it is determined that the operation lever device 52 is not operated (neutral position), and if it is less than the threshold value PI_ON, it is determined that the operation lever device 52 is operated. If the previous value does not exist because the process of step S100 is the first time of the mode determination process, the determination of step S100 is performed assuming that the previous value is less than the threshold value PI_ON.

When the determination result in step S100 is YES, that is, when the bucket 35 is operated by the operation lever device 52 during the time Δt, the timer T, which is a variable for counting the time, is reset to T. (T) = 0 (step S110), and 1 is added to the count N, which is a variable for counting the number of times the bucket 35 is operated by the operation lever device 52 (number of operations) (step S120). If the determination result in step S100 is NO, that is, if the bucket 35 is not operated by the operating lever device 52 during the time Δt, the time Δt is added to the timer T (step S111).

Subsequently, it is determined whether or not the timer T is smaller than the predetermined reference time Tmax (for example, 0.5 seconds) (step S130). When the determination result in step S100 is NO (in other words, when the bucket 35 is not operated by the operating lever device 52 during the reference time Tmax), the count N is reset and N (t) = 0. (Step S140).

Subsequently, when the determination result in step S130 is YES, or when the processing in step S140 is completed, it is determined whether or not the count N is equal to or greater than the predetermined reference number Nmax (for example, twice). (Step S150). If the determination result in step S150 is YES, in other words, the number of times the bucket 35 is operated by the operation lever device 52 within a certain time (here, the reference time Tmax) is a certain number of times (here, the reference number Nmax). When the above occurs, the mode is switched to the response priority mode (step S160), and when the determination result in step S150 is NO, the mode is switched to the normal mode (step S161), and the mode determination process (steps S100 to S161) is performed. repeat.

The operation of the present embodiment configured as described above will be described.

In the work machine 100 of the present embodiment, when the operation amount of the operation lever device 52 is changed intermittently and frequently in a short time, that is, the operation is performed such as a gravel sowing operation or a concrete glass sieving operation. When the operation of tilting the lever device 52 in the bucket dump direction (or the direction of the cloud) and the operation of returning the lever device 52 are repeated in a short time, the mode is switched to the responsiveness priority mode. When switched to the responsiveness priority mode, the depressurization of the control signal of the regulator 42 by the proportional solenoid valve 45 is invalidated. As a result, the pump volume can be increased in an operation in which the operation amount of the operation lever device 52 changes intermittently and frequently in a short time, so that the responsiveness of the bucket operation can be improved.

Further, when a normal operation other than the operation in which the responsiveness priority mode is set is performed, the normal mode is set. When the mode is switched to the normal mode, the control signal input to the regulator 42 by the proportional solenoid valve 45 is depressurized and limited (adjusted) according to the operation amount of the operation lever device 52. In adjusting the control signal at this time, an optimized table (see bucket dump target volume calculation units T1 and T2) that can minimize excessive pressure loss in the control valve 44 and flow rate loss from the center bypass passage is used. , Fuel consumption can be reduced.

The effects of the present embodiment configured as described above will be described.

As a conventional technique for reducing the flow rate loss in the flow of hydraulic energy from the hydraulic pump to the hydraulic actuator, for example, in the area of fine operation of the lever operation amount such that the hydraulic actuator does not require a large flow rate, the pump of the hydraulic pump It is known that by reducing the volume, the loss of the bleed-off flow rate at which unnecessary pump discharge flow rate is thrown into the tank is reduced. In addition, by adjusting the pump reference flow rate according to the lever operation amount to the minimum required pump discharge flow rate according to the opening of the bleed-off valve, pressure loss and bleed-off flow rate loss are minimized without deteriorating operability. Some are known to suppress the pressure.

However, the response of the increase / decrease of the discharge flow rate in the variable volume hydraulic pump tends to be slower than the response of the directional control valve or the electronically controlled bleed-off valve. Therefore, it takes time for the discharge flow rate of the hydraulic pump to reach an appropriate discharge flow rate with respect to the opening degree of the directional control valve or the bleed-off valve, so that the discharge pressure of the hydraulic pump does not increase until it overcomes the load pressure of the hydraulic actuator. , There is a problem that the operation of the hydraulic actuator is delayed. In other words, when the operating lever is operated intermittently and quickly, the operating lever is returned before the pump flow rate has finished increasing, so the pump flow rate is smaller than in steady operation, and the operation of the hydraulic actuator is extremely deteriorated. Is a concern. In particular, when a solenoid valve generates a flow control signal pressure for a hydraulic pump, a sudden change in the pump control signal pressure due to a delay in controlling the solenoid valve or a decrease in signal pressure due to pressure loss when passing through the solenoid valve. Was not possible in some cases.

Specifically, as work that requires responsiveness in a hydraulic excavator, for example, a skeleton bucket (a bucket that has a mesh-like hole in the bottom of the bucket and has a structure in which fine earth and sand fall down) is attached. There is a sieving operation of the concreed gala to be performed. In such sieving work, it is necessary to vibrate the bucket part by continuously turning back the bucket operation (which may be accompanied by arm operation) to sift the glass in the bucket. There is a concern that the actuator will not operate sufficiently due to the delay in rising.

On the other hand, in the present embodiment, the variable displacement hydraulic pump 41 driven by the prime mover (for example, the engine 22) and a plurality of driven members (for example, the boom 31, the arm 33, and the bucket 35) rotate. A plurality of hydraulic actuators (for example, a boom cylinder 32) that are driven by an articulated front working machine 30 that is movably connected and configured and a pressure oil discharged from a hydraulic pump to drive a plurality of driven members. , Arm cylinder 34, bucket cylinder 36), a plurality of direction switching valves (for example, control valve 44) for controlling the direction and flow rate of pressure oil supplied from the hydraulic pump to the plurality of hydraulic actuators, and a plurality of direction switching. A plurality of operating devices for controlling the valve (for example, an operating lever device 52) and one or more operating amount detecting devices (for example, an operating pilot pressure sensor) for detecting the operating amount of at least one of the plurality of operating devices. SE1, SE2), a regulator 42 that controls the pump volume of the hydraulic pump based on a pump control signal generated according to the operation amount of at least one of the plurality of operating devices, and input to the regulator. At least one operation amount detection of a signal adjustment valve (for example, a proportional electromagnetic valve 45) capable of adjusting a pump control signal and an operation amount detection device for detecting an operation amount of an operation device related to generation of a pump control signal. It is equipped with a controller that controls the signal adjustment valve based on the detection result of the amount of operation from the device, and the controller adjusts the pump control signal by the signal adjustment valve and the normal mode in which the pump control signal is adjusted by the signal adjustment valve. Since it is configured so that it can be switched to either the responsiveness priority mode that is not performed, it is paraphrased when the operation lever is operated intermittently and quickly to vibrate the bucket, such as gravel sowing operation or sieving operation. In addition, the pump volume (discharge flow rate) of the hydraulic pump can be switched to the responsiveness priority mode in operations that require responsiveness, such as when the operating amount of the operating lever device changes intermittently and frequently in a short time. ) It is possible to achieve both reduction of pressure loss and flow rate loss by control and responsiveness of the hydraulic actuator by intermittent sudden lever operation.

In the present embodiment, a case where the bucket operation is configured to switch between the normal mode and the responsiveness priority mode and change the control mode of the pump volume according to the operation mode has been described as an example. The same effect can be obtained, for example, when the arm operation is configured to switch between the normal mode and the responsiveness priority mode instead of (or in addition to) the bucket operation.

<Modified example of the first embodiment>
A modified example of the first embodiment will be described with reference to FIGS. 6 to 8.

In this modification, in the first embodiment, it is possible to set whether or not to switch the operation mode from the normal mode to the responsiveness priority mode for each work mode set according to the work content performed by the front work machine. It is configured.

FIG. 6 is a functional block diagram showing the calculation contents of the pump target volume in the controller.

In FIG. 6, the controller 60A includes a pump target volume calculation unit C1, a pump control signal pressure target value calculation unit C2, a responsiveness priority mode switching unit C3, a pump flow rate control proportional solenoid valve valid / invalid switching unit C4, and a proportional solenoid valve current. It includes a calculation unit C5 and a responsiveness priority mode enable / disable switching unit C6. Further, the controller 60A is arranged in the cabinet 23 and operates a monitor (display device) 63a for displaying various information and setting screens related to the hydraulic excavator 100 and various setting screens displayed on the monitor 63a. The input / output device 63 in which the switch group 63b is arranged is connected. Since the operation switch group 63b only needs to be able to operate the contents displayed on the monitor 63a, for example, a configuration may be adopted in which selection or determination is made by rotating and pressing the rotation switch.

The pump target volume calculation unit C1 calculates the pump target volume based on the lever operation amount (operation pilot pressure) of the operation lever device 52 detected by the operation pilot pressure sensors SE1 and SE2 and a predetermined table.

The pump control signal pressure target value calculation unit C2 calculates the pump control signal secondary pressure target value based on the pump target volume calculated by the pump target volume calculation unit C1 and a predetermined table. The table used to calculate the secondary pressure target value of the pump control signal from the pump target volume is set from the change characteristics of the pump volume of the hydraulic pump 41 due to the pump control signal pressure set hard by the positive control type regulator 42. To do.

The responsiveness priority mode switching unit C3 determines whether or not the operation requires the responsiveness of the bucket operation based on the lever operation amount of the operation lever device 52 detected by the operation pilot pressure sensors SE1 and SE2. If it is determined that the operation requires responsiveness, the operation mode is switched to the responsiveness priority mode, and if not, the operation mode is switched to the normal mode.

The responsiveness priority mode enable / disable switching unit 6C responds based on the work mode signal from the input / output device (work mode setting device) 63 and the predetermined valid / invalid determination table 300 (see FIG. 8 below). The pump flow rate control proportional solenoid valve of the operation mode switched by the sex priority mode switching unit C3 enables / disables the output to the switching unit C4.

The work mode signal input to the responsiveness priority mode enable / disable switching unit 6C is output corresponding to the work mode set in the input / output device (work mode setting device) 63, and is output from the front work machine 30. It is set by the operator according to the work to be done in. The responsiveness priority mode valid / invalid switching unit 6C selects the responsiveness priority mode among the operation modes switched by the responsiveness priority mode switching unit C3 based on the work mode signal and the predetermined valid / invalidity determination table 300. Switch between enabling and disabling. Specifically, the responsiveness priority mode valid / invalid switching unit 6C determines whether valid / invalid is set in the valid / invalid determination table 300 for the work mode based on the work mode signal, and is set to valid. If so, the signal indicating the result of the operation mode switched by the responsiveness priority mode enable / disable switching unit 6C (that is, "normal mode" or "responsiveness priority mode") is directly used as the pump flow rate control proportional solenoid valve. Output to the valid / invalid switching unit C4. Further, the responsiveness priority mode enable / disable switching unit 6C determines that the responsiveness priority mode is invalid when the work mode based on the work mode signal is set to be invalid, and determines that the responsiveness priority mode is valid. Regardless of the operation mode switched by the invalid switching unit 6C (that is, regardless of whether the operation mode is the "normal mode" or the "responsive priority mode"), the signal indicating the "normal mode" is sent to the pump flow rate. Output to the control proportional solenoid valve enable / disable switching unit C4. The valid / invalid determination table may be set by the input / output device 63 and stored in the responsiveness priority mode valid / invalid switching unit 6C.

The pump flow control proportional electromagnetic valve enable / disable switching unit C4 is the calculation result of the pump control signal pressure target value calculation unit C2 (pump control signal 2) according to the operation mode switched by the response priority mode enable / disable switching unit 6C. The handling of the next pressure target value) is switched, and when the operation mode is switched to the normal mode, the output of the pump control signal pressure target value calculation unit C2 is used as it is in the subsequent processing block (proportional electromagnetic valve current calculation). When the output is output to unit C5) and the operation mode is switched to the responsiveness priority mode, the pump control signal secondary pressure target value is replaced with the maximum pilot pressure (for example, 4 MPa) of the hydraulic circuit system 40 in the subsequent stage. Output to the processing block (proportional electromagnetic valve current calculation unit C5).

The proportional solenoid valve current calculation unit C5 outputs a control signal of the proportional solenoid valve 45 based on the target pressure of the proportional solenoid valve 45 input from the pump flow control proportional solenoid valve valid / invalid switching unit C4 and a predetermined table. It calculates and outputs, and drives the proportional solenoid valve 45. That is, when the responsiveness priority mode switching unit C3 is switched to the normal mode, the pump control signal primary pressure becomes the pump control signal secondary pressure based on the calculation result of the pump control signal pressure target value calculation unit C2. The proportional solenoid valve 45 is driven so as to reduce the pressure, and when the operation mode is switched to the responsive priority mode, the proportional solenoid valve 45 is driven so that the pressure reduction in the proportional solenoid valve 45 becomes invalid.

FIG. 7 is a diagram showing an example of a setting menu configuration displayed on a monitor (display device) of the input / output device.

As shown in FIG. 7, the information that can be displayed on the monitor 63a of the input / output device 63 by the operation of the operation switch group 63b by the operator includes the information menu 210 and the setting menu 220 displayed by selecting the main menu 200. In addition, there is a work mode setting menu 230 for setting a work mode according to the work contents performed by the front work machine 30. When the work mode setting menu 230 is selected, for example, excavation mode 231, crane mode 232, breaker mode 233, subdivision machine mode 234, crusher mode 235, tilt bucket mode 236, etc. are displayed as work modes, and the operator can display them. The working mode is set by selecting the desired working mode. From the input / output device 63, a work mode signal indicating the set work mode is output to the responsiveness priority mode enable / disable switching unit 6C of the controller 60A.

FIG. 8 is a diagram showing an example of an enable / invalid determination table for determining whether or not to switch to the responsiveness priority mode for each work mode.

In FIG. 8, the valid / invalid determination table 300 is capable of switching to a plurality of types of work modes 301 and a responsiveness priority mode set corresponding to each work mode, that is, whether it is valid or invalid. It is composed of the setting state 302 of. In the valid / invalid determination table 300, for example, in the crane mode 232 that requires delicate movement and the breaker mode 233 that uses a heavy attachment whose movement is likely to change suddenly, the switching to the responsiveness priority mode is set to invalid. ing. On the other hand, in the excavation mode 231 and the tilt bucket mode 236, there is a possibility that responsiveness is required such as sieving of the glass and gravel sowing, so switching to the responsiveness priority mode is effective. It is set.

Other configurations are the same as in the first embodiment.

In the present modification configured as described above, the same effect as that of the first embodiment can be obtained.

In addition, since the responsiveness priority mode can be disabled in a predetermined work mode, the responsiveness priority mode is set in the work mode that requires delicate operation or the work mode that uses a heavy attachment whose movement is likely to change suddenly. Switching can be disabled, and operability can be improved.

<Second Embodiment>
A second embodiment of the present invention will be described with reference to FIGS. 9 and 10. In this embodiment, only the differences from the first embodiment will be described, and the same members as those in the first embodiment are designated by the same reference numerals in the drawings, and the description thereof will be omitted.

This embodiment shows a case where a negative control method is adopted for the regulator of the first embodiment.

FIG. 9 is a diagram schematically showing a main part of the hydraulic circuit system according to the present embodiment by extracting it. Note that, in FIG. 9, only the bucket cylinder 36 and its related configuration are shown on behalf of the plurality of hydraulic actuators, and the other hydraulic actuators and their related configurations are not shown for the sake of simplicity.

In FIG. 9, the hydraulic circuit system 40B includes a variable-volume hydraulic pump 41 driven by an engine 22, a fixed-volume pilot pump (pilot hydraulic source) 49, and a hydraulic oil tank which is a hydraulic oil supply source of the hydraulic pump. It is supplied from the hydraulic pump 41 to the hydraulic actuator (bucket cylinder) 36 via the discharge line L4 based on the operation pilot pressure (operation signal) guided by the pilot lines L1 and L2 from the operation lever device 52 for bucket operation. A control valve (direction switching valve) 44 that controls the direction and flow rate of the hydraulic oil, and an operation pilot pressure sensor (operation) that detects the operation amount of the operation lever device 52 by detecting the operation pilot pressure of the pilot lines L1 and L2. Volume detection devices) SE1 and SE2, and a regulator 42a that controls the pump volume (tilt angle) of the hydraulic pump 41 based on the pilot pressure (pump control signal) generated in response to the operation of the operation lever device 52. A proportional electromagnetic valve 56 (signal adjusting valve) capable of adjusting the pump control signal input from the lever device 52 to the regulator 42a, and a proportional electromagnetic valve 56 based on the detection result of the operation amount from the operation pilot pressure sensors SE1 and SE2. It is roughly configured from the controller 60B to be controlled. A relief valve 41a that defines an upper limit of the discharge pressure of the hydraulic pump 41 is installed in the discharge line L4 from the hydraulic pump 41.

At the most downstream of the center bypass line L5, which is the return line of the pressure oil from the control valve 44 to the hydraulic oil tank 48, the throttle 53 and the upper limit of the pressure on the control valve 44 side (that is, the hydraulic pump 41 side) of the throttle 53 A relief valve 54 is installed. The pressure (called the pump flow rate control signal) on the control valve 44 side (that is, the hydraulic pump 41 side) of the throttle 53 and the pressure generated by reducing the discharge pressure of the pilot pump 49 with the proportional electromagnetic valve 56 (pump flow rate). Each of the drop signals) is guided to the shuttle valve 55, and the larger pressure is selectively output to the pilot line L13 as a pump control signal (pilot pressure) and input to the regulator to 42a. The regulator 42a is a negative control system that reduces the pump volume of the hydraulic pump 41 as the input pilot pressure (pump control signal) increases.

The controller 60B calculates the pump target volume of the hydraulic pump 41 based on the detection results of the operation pilot pressure sensors SE1 and SE2, and controls the proportional solenoid valve 56 based on the pump target volume. That is, the proportional solenoid valve 56 and the shuttle valve 55 generate a pump flow rate decrease signal by changing the opening area based on the control signal from the controller 60B, and supply the pump flow rate decrease signal to the pilot line L13 via the shuttle valve 55. Therefore, a signal adjusting valve capable of adjusting the pump control signal input to the regulator 42a is configured. Since the proportional solenoid valve 56 is held at the position (maximum opening area) shown in FIG. 2 when there is no control signal from the controller 60B, the proportional solenoid valve 56 moves upward in FIG. 2 as the control signal increases and has an opening area. Decreases. The proportional electromagnetic valve 56 is controlled to take a larger opening area when the hydraulic actuator does not require a large flow rate, that is, when the lever operation amount is in the fine operation area, and sends a pump flow rate decrease signal. By inputting to the regulator 42a as a pump control signal via the shuttle valve 55, the discharge flow rate of the pressure hydraulic pump of the pump control signal is reduced, and the unnecessary pump discharge flow rate is discarded in the tank. Reduce.

FIG. 10 is a functional block diagram showing the calculation contents of the pump target volume in the controller.

In FIG. 10, the controller 60B includes a pump target volume calculation unit C1, a pump flow rate reduction signal pressure target value calculation unit C12, a responsiveness priority mode switching unit C3, a pump flow rate reduction proportional solenoid valve valid / invalid switching unit C14, and proportional. The solenoid valve current calculation unit C5 is provided.

The pump target volume calculation unit C1 calculates the pump target volume based on the lever operation amount (operation pilot pressure) of the operation lever device 52 detected by the operation pilot pressure sensors SE1 and SE2 and a predetermined table.

The pump flow rate decrease signal pressure target value calculation unit C12 calculates the pump flow rate decrease signal target pressure based on the pump target volume calculated by the pump target volume calculation unit C1 and a predetermined table. The table used to calculate the pump flow rate decrease signal target pressure from the pump target volume is based on the change characteristics of the pump volume of the hydraulic pump 41 due to the pump control signal (pilot pressure) set hard by the negative control type regulator 42a. Set.

The responsiveness priority mode switching unit C3 determines whether or not the operation requires the responsiveness of the bucket operation based on the lever operation amount of the operation lever device 52 detected by the operation pilot pressure sensors SE1 and SE2. If it is determined that the operation requires responsiveness, the operation mode is switched to the responsiveness priority mode, and if not, the operation mode is switched to the normal mode.

The pump flow rate decrease proportional electromagnetic valve enable / disable switching unit C14 is the calculation result (pump flow rate decrease signal) of the pump flow rate decrease signal pressure target value calculation unit C12 according to the operation mode switched by the response priority mode switching unit C3. The handling is switched, and when the operation mode is switched to the normal mode, the output of the pump flow rate reduction signal pressure target value calculation unit C12 is directly output to the subsequent processing block (proportional electromagnetic valve current calculation unit C5). However, when the operation mode is switched to the responsiveness priority mode, the pump flow rate decrease signal is replaced with the minimum pilot pressure (for example, 0 (zero) MPa) of the hydraulic circuit system 40 to replace the processing block (proportional electromagnetic wave) in the subsequent stage. Output to the valve current calculation unit C5).

The proportional solenoid valve current calculation unit C5 outputs a control signal of the proportional solenoid valve 56 based on a target pressure of the proportional solenoid valve 56 input from the pump flow rate reduction proportional solenoid valve enable / invalid switching unit C14 and a predetermined table. It calculates and outputs, and drives the proportional solenoid valve 56. That is, when the responsiveness priority mode switching unit C3 is switched to the normal mode, the proportional solenoid valve is generated so that the pump flow rate reduction signal is generated based on the calculation result of the pump flow rate reduction signal pressure target value calculation unit C12. 56 is driven, and when the operation mode is switched to the responsiveness priority mode, the proportional solenoid valve 56 is driven so that the depressurization by the proportional solenoid valve 56 becomes invalid.

Other configurations are the same as in the first embodiment.

The operation and effect of the present embodiment configured as described above will be described.

In the work machine 100 of the present embodiment, when the operation amount of the operation lever device 52 is changed intermittently and frequently in a short time, that is, the operation is performed such as a gravel sowing operation or a concrete glass sieving operation. When the operation of tilting the lever device 52 in the bucket dump direction (or the direction of the cloud) and the operation of returning the lever device 52 are repeated in a short time, the mode is switched to the responsiveness priority mode. When the responsiveness priority mode is switched, the generation of the pump flow rate decrease signal by the proportional solenoid valve 56 and the input as the pump control signal to the regulator 42a via the shuttle valve 55 are invalidated. As a result, the pressure (pump flow rate control signal) on the hydraulic pump 41 side of the throttle 53 of the center bypass line L5 is always selected as the pump control signal by the shuttle valve 55, so that the operation amount of the operation lever device 52 is intermittent in a short time. The pump volume can be increased and the responsiveness of the bucket operation can be improved in the operation that changes frequently and frequently.

Further, when a normal operation other than the operation in which the responsiveness priority mode is set is performed, the normal mode is set. When the mode is switched to the normal mode, the proportional electromagnetic valve 56 enables the generation of the pump flow rate decrease signal according to the operation amount of the operation lever device 52, and inputs the pump control signal to the regulator 42a via the shuttle valve 55, resulting in the result. The input pump control signal is adjusted to the regulator 42a. In adjusting the control signal at this time, an optimized table (see bucket dump target volume calculation units T1 and T2) that can minimize excessive pressure loss in the control valve 44 and flow rate loss from the center bypass passage is used. , Fuel consumption can be reduced.

Next, the features of each of the above embodiments will be described.

(1) In the above embodiment, the variable displacement hydraulic pump 41 driven by a prime mover (for example, engine 22) and a plurality of driven members (for example, boom 31, arm 33, bucket 35) rotate. A plurality of hydraulic actuators (for example, boom cylinders) driven by an articulated front working machine 30 configured to be connectably connected and pressure oil discharged from the hydraulic pump to drive the plurality of driven members, respectively. 32, arm cylinder 34, bucket cylinder 36), a plurality of direction switching valves (for example, control valve 44) that control the direction and flow rate of pressure oil supplied from the hydraulic pump to the plurality of hydraulic actuators, respectively. A plurality of operating devices for controlling a plurality of direction switching valves (for example, an operating lever device 52) and one or more operating amount detecting devices (for example, for detecting the operating amount of at least one of the plurality of operating devices). , Operation pilot pressure sensors SE1, SE2), and a regulator 42 that controls the pump volume of the hydraulic pump based on a pump control signal generated according to the operation amount of at least one operation device among the plurality of operation devices. A signal adjusting valve (for example, proportional electromagnetic valve 45; shuttle valve 55, proportional electromagnetic valve 56) capable of adjusting the pump control signal input to the regulator, and an operating amount of an operating device related to the generation of the pump control signal. A controller for controlling the signal adjusting valve based on the detection result of the operating amount from at least one operating amount detecting device among the operating amount detecting devices to be detected is provided, and the controller is the pump by the signal adjusting valve. It is assumed that it is possible to switch between the normal mode in which the control signal is adjusted and the responsiveness priority mode in which the pump control signal is not adjusted by the signal adjusting valve.

As a result, when the operation lever is operated intermittently and quickly to vibrate the bucket, such as a gravel-sowing operation or a sieving operation, in other words, when the operation amount of the operation lever device changes intermittently and frequently in a short time. Since it is possible to switch to the responsiveness priority mode for operations that require responsiveness such as, response such as operations in which the operation amount of the operation lever changes frequently in a short time without deteriorating workability during normal operation. It is possible to increase the responsiveness in the operation that requires sexuality, and it is possible to suppress the decrease in work efficiency.

(2) Further, in the above embodiment, in the work machine of (1), the regulator is a positive control system in which the pump volume of the hydraulic pump is increased as the pump control signal is increased, and the signal is The regulating valve is a proportional solenoid valve capable of reducing the pilot pressure input to the regulator as a pump control signal.

(3) Further, in the above embodiment, in the work machine of (1), the controller has a predetermined number of times that the operation amount of the operation device has increased beyond a predetermined threshold value within a predetermined fixed time. When the specified number of times is exceeded, the mode is switched to the responsiveness priority mode in which the pump control signal is not adjusted by the signal adjusting valve.

(4) Further, in the above-described embodiment, the work machine of (1) is provided with a work mode setting device for setting a work mode according to the work content performed by the front work machine, and the controller is the work mode. When the work mode set by the setting device is preset so that the responsiveness priority mode is invalid, the work mode is not switched to the responsiveness priority mode.

As a result, the responsiveness priority mode can be disabled in a predetermined work mode. Therefore, in the work mode that requires delicate operation or the work mode that uses a heavy attachment whose movement is likely to change suddenly, the responsiveness priority mode is used. Switching to can be disabled and operability can be improved.

(5) Further, in the above embodiment, in the work machine of (1), the regulator is a negative control method in which the pump volume of the hydraulic pump is reduced as the pump control signal increases, and the signal is The regulating valve is generated to limit the pump volume control pilot pressure generated so as to decrease as the operation amount of the operating device related to the generation of the pump control signal increases, and the pump volume of the hydraulic pump. It has a shuttle valve that selectively guides the larger pump volume limiting pilot pressure as a pump control signal to the regulator, and a proportional electromagnetic valve capable of reducing the pump volume limiting pilot pressure input to the shuttle valve. I made it.

<Additional notes>
In the above embodiment, a general hydraulic excavator in which a hydraulic pump is driven by a prime mover such as an engine has been described as an example, but a hybrid type hydraulic excavator in which the hydraulic pump is driven by an engine and a motor, and Needless to say, the present invention can be applied to an electric hydraulic excavator or the like in which a hydraulic pump is driven only by a motor.

Further, the present invention is not limited to the above-described embodiment, and includes various modifications and combinations within a range not deviating from the gist thereof. That is, in each of the above embodiments, the case where the pump control signal is generated according to the operation amount of the operation lever device 52 related to the bucket 35 has been described as an example, but the present invention is not limited to this, and the configuration is not limited to the bucket 35. When a pump control signal is generated according to the operation amount of the related hydraulic actuator (for example, boom cylinder 32, arm cylinder 34, swing hydraulic motor 27, etc.), that is, by using the operation amounts of a plurality of hydraulic actuators in combination. The present invention may be applied. Further, in each of the above embodiments, the case of switching between the normal mode and the responsiveness priority mode based on the operation amount of the operation lever device 52 related to the bucket 35 has been described as an example, but the present invention is not limited to this, and the operation lever is not limited to this. Responds to normal mode based on the amount of operation of the hydraulic actuator (eg, the arm cylinder 34 associated with the arm 33 which may be operated quickly when vibrating the bucket) related to the configuration which may be operated intermittently and quickly. It may be configured to switch between the sex priority mode, or it may be configured to switch between the normal mode and the responsiveness priority mode by using these manipulation amounts in combination.

Further, the present invention is not limited to the one including all the configurations described in the above-described embodiment, and includes the one in which a part of the configurations is deleted. Further, each of the above configurations, functions and the like may be realized by designing a part or all of them by, for example, an integrated circuit. Further, each of the above configurations, functions, and the like may be realized by software by the processor interpreting and executing a program that realizes each function.

10 ... lower traveling body, 11a (11b) ... crawler, 12a (12b) ... crawler frame, 13a (13b) ... traveling hydraulic motor, 13b ... traveling hydraulic motor, 20 ... upper swing body, 21 ... swivel frame, 22 ... engine , 23 ... cab (cabinet), 26 ... reduction mechanism, 27 ... swivel hydraulic motor, 30 ... front device (front work machine), 31 ... boom, 32 ... boom cylinder, 33 ... arm, 35 ... bucket, 36 ... bucket Cylinder, 36a ... Bucket cylinder bottom chamber, 36b ... Bucket cylinder rod chamber, 40, 40B ... Hydraulic circuit system, 41 ... Hydraulic pump, 41a ... Relief valve, 42, 42a ... Regulator, 43 ... Shuttle valve, 44 ... Control valve ( Direction switching valve), 44a ... Check valve, 45, 56 ... Proportional electromagnetic valve, 48 ... Hydraulic oil tank, 49 ... Pilot pump (Pilot hydraulic source), 52 ... Operating lever device (Operating device), 52a ... Operating lever, 52b ... operation signal generator, 52b ... operation signal generator, 53 ... throttle, 54 ... relief valve, 55 ... shuttle valve, 60, 60A, 60B ... controller, 63 ... input / output device (work mode setting device), 63a ... monitor (Display device), 63b ... Operation switch group, 100 ... Hydraulic excavator (work machine), 200 ... Main menu, 210 ... Information menu, 220 ... Setting menu, 230 ... Work mode setting menu, SE1, SE2 ... Operation pilot pressure sensor (Operation amount detection device)

Claims (4)

A variable displacement hydraulic pump driven by a prime mover,
An articulated front work machine composed of a plurality of driven members rotatably connected to each other.
A plurality of hydraulic actuators driven by the pressure oil discharged from the hydraulic pump to drive the plurality of driven members, respectively.
A plurality of direction switching valves for controlling the direction and flow rate of the pressure oil supplied from the hydraulic pump to the plurality of hydraulic actuators, respectively.
A plurality of operating devices for controlling the plurality of directional control valves, and
One or more operation amount detection devices that detect the operation amount of at least one operation device among the plurality of operation devices, and
A regulator that controls the pump volume of the hydraulic pump based on a pump control signal pressure generated according to the operation amount of at least one of the plurality of operating devices.
A signal regulating valve capable of adjusting the pump control signal pressure input to the regulator, and
The signal adjusting valve is controlled based on the detection result of the operation amount from at least one operation amount detection device of the operation amount detection device that detects the operation amount of the operation device related to the generation of the pump control signal pressure. Equipped with a controller
The controller does not adjust the pump control signal pressure by the signal adjusting valve in a normal mode in which the pump control signal pressure is adjusted so that the pump volume of the hydraulic pump is reduced, and the pump control signal pressure is not adjusted by the signal adjusting valve. , It is possible to switch to either one of the responsiveness priority mode for controlling the pump volume of the hydraulic pump by the pump control signal pressure generated according to the operation amount of at least one of the plurality of operating devices. der is,
When the number of times the operating amount of the operating device rises beyond the predetermined threshold value within a predetermined fixed time exceeds the predetermined number of times, the mode is switched to the responsiveness priority mode, and in other cases, the above-mentioned work machine which is characterized that you set in the normal mode. In the work machine according to claim 1,
The regulator is a positive control system that increases the pump volume of the hydraulic pump as the pump control signal pressure increases.
The signal regulating valve is a work machine characterized by being a proportional solenoid valve capable of reducing the pilot pressure input to the regulator as a pump control signal pressure . In the work machine according to claim 1,
A work mode setting device for setting a work mode according to the work contents performed by the front work machine is provided.
The controller does not switch to the responsiveness priority mode when the responsiveness priority mode is set in advance for the work mode set by the work mode setting device. .. In the work machine according to claim 1,
The regulator is a negative control system in which the pump volume of the hydraulic pump is reduced as the pump control signal pressure increases.
The signal regulating valve is
The pump volume control pilot pressure generated so as to decrease as the operation amount of the operating device related to the generation of the pump control signal pressure increases, and the pump volume generated to limit the pump volume of the hydraulic pump. A shuttle valve that selectively guides the larger limiting pilot pressure as the pump control signal pressure to the regulator,
A work machine having a proportional solenoid valve capable of reducing the pump volume limiting pilot pressure input to the shuttle valve.

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