JP2019173363A - Hydraulic oil amount measuring device for construction machine - Google Patents

Abstract

To provide a hydraulic oil amount measuring device that makes it possible to appropriately check the hydraulic oil amount regardless of an operation state of a hydraulic cylinder provided in a construction machine.SOLUTION: Hydraulic excavator 1 (construction machine) comprises an operation state information acquisition unit 31 for acquiring operation state information of hydraulic cylinders 12a, 12b, and 12c, a cylinder oil amount estimation unit 32 for estimating the cylinder oil amount held by the hydraulic cylinders 12a, 12b, and 12c based on the operation state information, a tank oil amount measuring unit 33 for measuring the tank oil amount of an oil tank 21, and an oil amount information notifying unit 34 for outputting notification information relating to the propriety or decrease degree of the hydraulic oil amount in the hydraulic excavator 1 based on the estimated value of the cylinder oil amount and the measured value of the tank oil amount.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an apparatus for measuring the amount of hydraulic oil of a construction machine such as a hydraulic excavator.

  In a construction machine such as a hydraulic excavator, during operation, the hydraulic oil stored in an oil tank is supplied to a hydraulic actuator such as a hydraulic cylinder via a hydraulic pump to operate the hydraulic actuator. The hydraulic oil discharged from the actuator is returned to the oil tank.

  In this type of construction machine, for example, as seen in Patent Document 1, a level gauge indicating the liquid level of the hydraulic oil in the oil tank is attached to the oil tank, and the level gauge is visually recognized. It is generally known that it is possible to confirm whether or not the amount of hydraulic oil in the tank is within an appropriate amount range.

JP 2007-212382 A

  A hydraulic actuator provided in a construction machine such as a hydraulic excavator generally includes a relatively large hydraulic cylinder. In the hydraulic cylinder, the amount of hydraulic oil filled in the entire oil chamber changes according to the operating state (expanded state) of the hydraulic cylinder. As a result, the amount of hydraulic oil in the oil tank also changes according to the operating state of the hydraulic cylinder.

  For this reason, in this type of construction machine, when the amount of hydraulic oil in the oil tank is confirmed using a level gauge such as that disclosed in Patent Document 1, normally, the reference operating state of the hydraulic cylinder for confirmation (or The posture state of a working device such as a boom, an arm, or a bucket driven by the hydraulic cylinder is determined.

  Then, after holding the hydraulic cylinder in the standard operation state, the operator checks the amount of hydraulic oil in the oil tank with a level gauge. Furthermore, when it is determined by this confirmation that the amount of hydraulic oil is insufficient, the operator replenishes the oil tank with the insufficient amount of hydraulic oil while visually checking the level gauge.

  However, in order to check the amount of hydraulic oil, it is often troublesome to operate the hydraulic cylinder to the reference operation state, and it is necessary to secure an operator who can operate the construction machine.

  Also, depending on the location of the construction machine and the like, there are many cases where it is difficult to operate the hydraulic cylinder to the reference operation state due to the occurrence of interference with surrounding objects. In such a case, it is necessary to move the construction machine to an appropriate location and then operate the hydraulic cylinder to the standard operating state. Prone to being unable to run on.

  The present invention has been made in view of such a background, and provides a hydraulic fluid amount measuring device that can appropriately check the hydraulic fluid amount regardless of the operating state of a hydraulic cylinder provided in a construction machine. The purpose is to provide.

In order to achieve the above object, a hydraulic oil measuring apparatus for construction machinery according to the present invention includes hydraulic oil in a construction machine including one or more hydraulic cylinders and an oil tank that stores hydraulic oil for driving the hydraulic cylinders. A quantity measuring device,
An operation state information acquisition unit for acquiring operation state information indicating an operation state of the hydraulic cylinder;
A cylinder oil amount estimation unit that estimates a cylinder oil amount that is a hydraulic oil amount possessed by the hydraulic cylinder based on the operation state information;
A tank oil amount measuring unit for measuring a tank oil amount that is the amount of hydraulic oil stored in the oil tank;
An oil amount information notifying unit that outputs notification information regarding the appropriateness or degree of decrease of the hydraulic oil amount in the construction machine based on at least the estimated value of the cylinder oil amount and the measured value of the tank oil amount. (First invention).

  In the present invention, the amount of hydraulic oil in the construction machine means the amount of hydraulic oil retained in the construction machine including the cylinder oil amount and the tank oil amount. In addition, the notification information regarding the appropriateness or the degree of decrease in the amount of hydraulic oil means that the person who receives the notification information determines whether the amount of hydraulic oil is appropriate or whether the amount of hydraulic oil is appropriate. This means information that can be recognized as to whether the level has decreased.

  According to the first aspect of the invention, the oil amount information notifying unit outputs the notification information based on at least the estimated value of the cylinder oil amount and the measured value of the tank oil amount. Can obtain information that can evaluate whether or not the amount of hydraulic oil held in the construction machine is appropriate, regardless of the operating state of the hydraulic cylinder provided in the construction machine.

  Therefore, according to the first aspect, it is possible to appropriately check the amount of hydraulic oil regardless of the operating state of the hydraulic cylinder provided in the construction machine.

  The first aspect of the invention further includes a temperature sensor that detects the temperature of the hydraulic oil stored in the oil tank, wherein the oil amount information notification unit is configured to estimate the cylinder oil amount. It is preferable that the notification information is output based on the measured value of the tank oil amount and the detected value of the temperature (second invention).

  According to this, it is possible to output the notification information in a mode that takes into account volume expansion according to the temperature of the hydraulic oil. As a result, the reliability of the notification information can be improved.

  In the first invention or the second invention, the oil amount information notification unit determines whether or not the hydraulic oil amount in the construction machine is in a shortage state, and measures at least the estimated value of the cylinder oil amount and the tank oil amount. When the determination result is affirmative, the information indicating that can be output as the notification information (third invention).

  According to this, since the said oil quantity information alerting | reporting part can judge appropriately whether the hydraulic oil quantity in the said construction machine is in a shortage state, irrespective of the operating state of a hydraulic cylinder, this hydraulic oil quantity is It is possible to output notification information indicating that a shortage has occurred at an appropriate timing.

  When the third invention is combined with the second invention, the oil amount information notification unit is based on the estimated value of the cylinder oil amount, the measured value of the tank oil amount, and the detected value of the temperature, It may be configured to determine whether or not the amount of hydraulic oil in the construction machine is in a shortage state.

  In the said 3rd invention, when the said judgment result is affirmative, it is preferable that the alerting | reporting information which the said oil quantity information alerting | reporting part outputs includes the information which shows the shortage amount of the hydraulic oil amount in the said construction machine (4th). invention).

  According to this, the person who receives the notification information can easily recognize the amount of hydraulic oil to be replenished in the oil tank.

  In the first to fourth inventions, the oil amount information notification unit is preferably configured to have a function of outputting the notification information to a portable terminal outside the construction machine (fifth invention).

  According to this, the person who possesses the portable terminal can obtain the notification information via the portable terminal near the inlet of the oil tank. For this reason, it is possible to smoothly perform the operation of replenishing hydraulic oil to the oil tank.

  In the fifth aspect of the invention, the oil amount information notifying unit sequentially obtains the measured value of the tank oil amount while the operation of the construction machine is stopped, and according to the change in the measured value of the tank oil amount, It is preferable that the notification information output to the portable terminal is changed (the sixth invention).

  According to this, the person who possesses the portable terminal can acquire the notification information via the portable terminal while performing the replenishment operation of the hydraulic oil to the oil tank. For this reason, it is possible to perform the replenishment operation of the hydraulic oil while confirming in real time whether or not the shortage of the hydraulic oil amount has been solved. As a result, the replenishment operation can be performed accurately.

A side view of a hydraulic excavator as an example of a construction machine in an embodiment of the present invention. The figure which shows the system configuration | structure of the principal part of the hydraulic excavator of embodiment. The figure which shows schematically the internal structure and hydraulic circuit structure of the hydraulic cylinder with which the hydraulic excavator of embodiment was equipped. The flowchart which shows the process of the control apparatus shown in FIG.

  An embodiment of the present invention will be described below with reference to FIGS. With reference to FIG. 1, the hydraulic oil amount measuring device of the present embodiment is provided in a hydraulic excavator 1 as an example of a construction machine. The hydraulic excavator 1 includes a crawler type traveling body 2, a revolving body 3 mounted on the traveling body 2, and a working device 4 attached to the revolving body 3.

  The traveling body 2 is assembled with a pair of hydraulic motors (not shown) as traveling actuators that respectively drive the left and right crawlers.

  The turning body 3 is attached to the traveling body 2 so as to be able to turn in the direction (yaw direction) around the turning axis Cz in the vertical direction with respect to the traveling body 2, and a hydraulic motor as a turning actuator. It is swiveled by a swivel drive device 7 including a swivel gear (not shown) and a swivel gear (not shown). A driver's cab 5 in which an operator is boarded is provided at the front part of the swivel body 3, and a machine room 6 in which various machines such as an engine and hydraulic equipment (not shown) are accommodated is provided at the rear part. ing.

  The working device 4 includes a boom 11a extending from the front portion of the revolving structure 3, an arm 11b extending from the distal end portion of the boom 11a, and an attachment 11c (in the illustrated example) assembled to the distal end portion of the arm 11b. Bucket), a boom hydraulic cylinder 12a as an actuator that swings the boom 11a in a pitch direction (a direction around the left and right axis of the swing body 3) with respect to the swing body 3, and an arm 11b with respect to the boom 11a. An arm hydraulic cylinder 12b as an actuator that swings in the direction is provided, and an attachment hydraulic cylinder 12c that swings the attachment 11c in the pitch direction with respect to the arm 11b.

  In the present embodiment, these hydraulic cylinders 12a, 12b, and 12c correspond to the hydraulic cylinders in the present invention. In the following description, when it is not necessary to distinguish between the hydraulic cylinders 12a, 12b, and 12c, each is simply referred to as a hydraulic cylinder 12.

  Further, as shown in FIG. 2, the hydraulic excavator 1 includes an oil tank 21 that stores hydraulic oil for driving each hydraulic actuator including the hydraulic cylinders 12 (12 a, 12 b, 12 c), and oil when the hydraulic actuators are operated. A hydraulic circuit device 22 configured to supply hydraulic oil from the tank 21 to each hydraulic actuator and return the hydraulic oil discharged from each hydraulic actuator to the oil tank 21 is mounted. The oil tank 21 and the hydraulic circuit device 22 are accommodated in the machine room 6.

  The hydraulic actuator includes a hydraulic motor for traveling the traveling body 2 and a hydraulic motor for pivoting the revolving body 3 in addition to the hydraulic cylinders 12a, 12b, and 12c.

  The hydraulic circuit device 22 has a known circuit configuration including a pump, a directional switching valve for each hydraulic actuator, and the like, and each hydraulic actuator is connected to the oil tank 21 via the hydraulic circuit device 22.

  FIG. 3 schematically shows the configuration of the hydraulic circuit device 22 relating to each hydraulic cylinder 12. As shown in the figure, each hydraulic cylinder 12 includes a cylinder 121, a piston 122 slidable in the axial direction in the cylinder 121, and a rod 123 extending from the piston 122. A bottom-side oil chamber 124a and a rod-side oil chamber 124b separated by the piston 122 are formed inside.

  The hydraulic circuit device 22 includes a direction switching valve 222 connected to the bottom side oil chamber 124a and the rod side oil chamber 124b of the hydraulic cylinder 12 via oil passages 221a and 221b, and the direction switching valve 222 as an oil tank. 21, a meter-in side oil passage 223 and a meter-out side oil passage 224 connected to 21, and a pump 225 interposed in the meter-in side oil passage 223.

  In this case, the direction switching valve 222 is driven by operating an operating device such as an operating lever (not shown) disposed in the cab 5 with the pump 225 being driven by an engine (not shown). And by the drive, the meter-in side oil passage 223 communicates with one side of the oil passages 221a and 221b, and the meter-out side oil passage 224 communicates with the other side of the oil passages 221a and 221b.

  Thus, the oil tank 21 is operated to one side of the bottom side oil chamber 124a and the rod side oil chamber 124b of the hydraulic cylinder 12 through one of the meter-in side oil passage 223, the direction switching valve 222, and the oil passages 221a and 221b. Oil is supplied, and hydraulic oil discharged from the other side of the bottom side oil chamber 124a and the rod side oil chamber 124b passes through the other of the oil passages 221a and 221b, the direction switching valve 222 and the meter-out side oil passage 224. Is returned to the oil tank 21.

  As a result, the hydraulic cylinder 12 is driven so that the piston 122 and the rod 123 of the hydraulic cylinder 12 move in the axial direction of the cylinder 121 (the rod 123 expands and contracts outside the cylinder 121).

  Returning to FIG. 2, the hydraulic excavator 1 further includes a control device 30 having a function of performing operation control of the hydraulic excavator 1, and a cylinder operation detection sensor 40 for detecting the operation state of each hydraulic cylinder 12. A liquid level sensor 41 for detecting the level of the hydraulic oil in the oil tank 21; a temperature sensor 42 for detecting the temperature of the hydraulic oil in the oil tank 21; A display 45 for displaying information is mounted. In addition, an oil amount gauge 43 capable of easily visually confirming the amount of hydraulic oil in the oil tank 21 is assembled to the side surface of the oil tank 21.

  The oil amount gauge 43 is a gauge having a known structure configured such that the liquid level or float height of the liquid inside thereof increases and decreases as the amount of hydraulic oil in the oil tank 21 increases and decreases. Alternatively, it is possible to recognize the amount of hydraulic oil in the oil tank 21 by visually recognizing the height (vertical position) of the float.

  The cylinder motion detection sensor 40 includes, for example, an angle sensor 40a that detects a rotation angle of the boom 11a with respect to the swing body 3 (hereinafter referred to as a first rotation angle) and a rotation angle of the arm 11b with respect to the boom 11a (hereinafter referred to as a second rotation). Angle sensor 40b for detecting an angle) and an angle sensor 40c for detecting a rotation angle of the attachment 11c with respect to the arm 11b (hereinafter, a third rotation angle). These angle sensors 40a, 40b, and 40c are constituted by, for example, a rotary encoder, a resolver, and the like, and are assembled to the work device 4.

  Here, each of the first rotation angle, the second rotation angle, and the third rotation angle includes the displacement amount of the rod 123 (or the piston 122) of the boom hydraulic cylinder 12a, the rod 123 (or the arm hydraulic cylinder 12b). Each of the displacement amount of the piston 122) and the displacement amount of the rod 123 (or the piston 122) of the attachment hydraulic cylinder 12c has a certain correlation. Therefore, based on the detected values of the first rotation angle, the second rotation angle, and the third rotation angle, the boom hydraulic cylinder 12a, the arm hydraulic cylinder 12b, and the attachment hydraulic cylinder 12c are based on the correlation. Each operation state can be specified.

  The cylinder motion detection sensor 40 is configured so that the displacement amount (stroke) of each rod 123 of the boom hydraulic cylinder 12a, the arm hydraulic cylinder 12b, and the attachment hydraulic cylinder 12c is used instead of the angle sensors 40a, 40b, and 40c. A displacement sensor capable of detecting (quantity) may be provided.

  The liquid level sensor 41 is constituted by, for example, a laser-type distance measuring sensor, and is assembled to the upper surface portion of the oil tank 21. In this case, the liquid level sensor 41 receives the reflected light while irradiating the laser light toward the liquid level of the hydraulic oil in the oil tank 21, thereby reaching the liquid level of the hydraulic oil in the oil tank 21. (In other words, the height of the liquid level) is measured by a triangulation method or a TOF method (TOF: Time of Flight), and a detection signal corresponding to the measured value of the distance is output.

  The liquid level sensor 41 is not limited to the laser type distance measuring sensor, and for example, an infrared type or ultrasonic type distance measuring sensor or a float type level sensor may be used.

  The temperature sensor 42 is composed of a thermistor or the like, and is assembled to the side surface of the oil tank 21 so that the temperature of the hydraulic oil in the oil tank 21 can be detected. The temperature sensor 42 may be assembled in an oil passage that communicates with the oil tank 21.

  The display unit 45 is configured by a liquid crystal display, an organic EL display, or the like, and is installed in the cab 5.

  The control device 30 is configured by one or more electronic circuit units including a microcomputer, a memory, an interface circuit, and the like. The control device 30 receives detection signals from the cylinder motion detection sensor 40, the liquid level sensor 41, and the temperature sensor 42.

  And the control apparatus 30 contains the function as a hydraulic fluid amount measuring apparatus as a function implement | achieved by both or one of the mounted hardware structure and program (software structure).

  More specifically, the control device 30 provides information indicating the operation state of each hydraulic cylinder 12 based on the detection signal of the cylinder operation detection sensor 40 (specifically, the displacement of the piston 122 or the rod 123 of each hydraulic cylinder 12). A function as an operation state information acquisition unit 31 for acquiring information) and the amount of hydraulic oil held by each hydraulic cylinder 12 (specifically, the bottom side oil chamber 124a and the rod side oil chamber 124b are filled entirely) The amount of hydraulic oil in the oil tank 21 (hereinafter, referred to as a cylinder oil amount estimation unit 32 that estimates the cylinder oil amount Vs) and the detection signal of the liquid level sensor 41 A function as a tank oil amount measuring unit 33 for measuring the tank oil amount Vt), and determining whether or not the hydraulic oil amount of the hydraulic excavator 1 is insufficient. And a function as an oil amount notification unit 34 to output the broadcast information.

  Furthermore, the control device 30 can control the display of the display unit 45, and can be used for a mobile terminal 50 such as a smartphone, a tablet terminal, or a feature phone, and Wi-Fi (registered trademark), Bluetooth (registered trademark), or the like. Wireless communication can be performed using a communication method. In this case, a predetermined application is installed in the portable terminal 50 in advance, and various information transmitted from the control device 30 can be displayed in a state where the application is activated.

  Next, the processing of the control device 30 relating to the hydraulic oil amount of the excavator 1 will be described with reference to the flowchart of FIG.

  When the control device 30 is activated (or the control device 30) in a state where the operation of the excavator 1 (specifically, the travel operation of the traveling body 2, the swing operation of the revolving structure 3, and the operation of the work device 4) is stopped. When a predetermined input operation is performed), the control device 30 executes the process shown in the flowchart of FIG.

  In STEP 1, the control device 30 executes a process of measuring the current tank oil amount Vt by the tank oil amount measuring unit 33. In this processing, the tank oil amount measuring unit 33 acquires the detection signal of the liquid level sensor 41 and detects the liquid level (the distance to the liquid level of the hydraulic oil in the oil tank 21) indicated by the detection signal. From the value, the tank oil amount Vt (measured value) is obtained using function data (arithmetic formula, map data, etc.) prepared in advance as a correlation between the liquid level and the tank oil amount.

  Next, in STEP 2, the control device 30 uses the operation state information acquisition unit 31 to acquire information indicating the current operation state of each hydraulic cylinder 12 (displacement amount of the rod 123 or the piston 122 of each hydraulic cylinder 12). Execute.

  In this process, the operation state information acquisition unit 31 takes in the detection signals of the cylinder operation detection sensor 40 (angle sensors 40a, 40b, 40c). Then, the operation state information acquisition unit 31 obtains a correlation between the first rotation angle and the displacement amount of the rod 123 (or piston 122) of the boom hydraulic cylinder 12a from the detection value of the first rotation angle by the angle sensor 40a. The displacement (measured value) of the rod 123 (or piston 122) of the boom hydraulic cylinder 12a is obtained using function data (calculation formula, map data, etc.) created in advance as a representation.

  Similarly, the operation state information acquisition unit 31 determines the correlation between the second rotation angle and the displacement amount of the rod 123 (or piston 122) of the arm hydraulic cylinder 12b from the detection value of the second rotation angle by the angle sensor 40b. The displacement amount (measured value) of the rod 123 (or piston 122) of the arm hydraulic cylinder 12b is obtained using the function data (calculation formula, map data, etc.) representing Further, the operation state information acquisition unit 31 obtains a correlation between the third rotation angle and the displacement amount of the rod 123 (or piston 122) of the attachment hydraulic cylinder 12c from the detection value of the third rotation angle by the angle sensor 40c. The displacement amount (measured value) of the rod 123 (or piston 122) of the attachment hydraulic cylinder 12c is obtained using the function data (calculation formula, map data, etc.).

  Note that the displacement amount of the rod 123 (or piston 122) of each hydraulic cylinder 12 obtained in STEP 2 is more specifically the displacement amount of the rod 123 (or piston 122) of each hydraulic cylinder 12 from the reference position. In this case, the reference position can be set arbitrarily.

  Next, in STEP 3, the control device 30 executes a process of estimating the current cylinder oil amount Vs of each hydraulic cylinder 12 by the cylinder oil amount estimation unit 32. In this process, the cylinder oil amount estimation unit 32 calculates the estimated value of the cylinder oil amount Vs of each hydraulic cylinder 12 by the following equations (1a) to (1c) defined according to the size of the hydraulic cylinder 12. .

Vs = V1 + V2 (1a)
However,
V1 = Volume of bottom side oil chamber = π × (Ds / 2) ² × L1 (1b)
V2 = volume of the oil chamber on the rod side = π × (Ds / 2) ² × L2−π × (Dr / 2) ² × L2 (1c)

  Here, referring to FIG. 3, Ds in the equations (1b) and (1c) is the inner diameter of the cylinder 121 of the hydraulic cylinder 12, Dr is the outer diameter of the rod 123 of the hydraulic cylinder 12, and L1 is the bottom side oil chamber 124a. , L2 is the length of the rod side oil chamber 124b in the axial direction.

  In this case, the values of Ds and Dr are stored and held in advance in the memory of the control device 30 for each hydraulic cylinder 12.

  L1 and L2 are the measured value of the displacement amount of the rod 123 (or piston 122) of each hydraulic cylinder 12, and L1 + L2 = L−L3 = a constant value (where L is the axial direction inside the cylinder 121) (Length, L3: thickness of piston 122).

  For example, in STEP 2, for each hydraulic cylinder 12, one value of L 1 and L 2 can be obtained as a measured value of the displacement amount of the rod 123 (or piston 122) of the hydraulic cylinder 12. In this case, the other value of L1 and L2 can be calculated from one value and the relational expression L1 + L2 = L−L3.

  In addition, without obtaining the values of L1 and L2 or the values of V1 and V2, separately, from the displacement amount of the rod 123 (or piston 122) of each hydraulic cylinder 12, for example, using map data or an arithmetic expression, It is also possible to directly determine the cylinder oil amount Vs of the hydraulic cylinder 12.

  As described above, the cylinder oil amount Vs (estimated value) obtained for each hydraulic cylinder 12 changes according to the displacement amount of the rod 123 (or piston 122) of each hydraulic cylinder 12. In this case, as the length of the rod 123 outside the cylindrical body 121 (the amount of protrusion from the cylindrical body 121) is larger, the volume of the rod 123 existing inside the cylindrical body 121 is decreased, and thus the cylinder oil amount Vs is increased. To do.

  In the following description, in order to distinguish the cylinder oil amount Vs for each hydraulic cylinder 12, the cylinder oil amount Vs of the boom hydraulic cylinder 12a is Vsa, the cylinder oil amount Vs of the arm hydraulic cylinder 12b is Vsb, and the attachment. The cylinder oil amount Vs of the hydraulic cylinder 12c for use may be expressed as Vsc.

  Returning to the description of FIG. 4, the control device 30 then performs the processing of STEP 4 to 9 by the oil amount information notification unit 34.

  In STEP 4, the oil amount information notification unit 34 calculates the tank oil amount Vt obtained in STEP 1 and the cylinder oil amounts Vsa, Vsb, Vsc of all the hydraulic cylinders 12 (12a, 12b, 12c) obtained in STEP 3. The total oil amount Vall (= Vt + Vsa + Vsb + Vsc) is calculated by adding the estimated value.

  Next, in STEP 5, the oil amount information notification unit 34 performs a process of correcting the calculated value of the total oil amount Vall according to the detected value of the current temperature Toil of the hydraulic oil indicated by the detection signal of the temperature sensor 42. To do. In this process, for example, a value Vall_c obtained by correcting the total oil amount Vall is obtained by calculating the following equations (2a) and (2b).

Vall_c = Vall−δ (Toil) (2a)
However,
δ (Toil) = Vall × α × (Toil−Tbase) (2b)

  Here, δ (Toil) is a volume expansion amount corresponding to the temperature Toil of the hydraulic oil, α is a thermal expansion coefficient of the hydraulic oil, and Tbase is a reference temperature (for example, normal temperature). By correcting the total oil amount Vall in this way, the corrected total oil amount Vall_c indicates the total oil amount at a predetermined reference temperature Tbase.

  When the deviation between the detected value of the hydraulic oil temperature Toil and the reference temperature Tbase falls within a predetermined range, or after the hydraulic excavator 1 stops operating, the hydraulic oil temperature Toil is equal to or close to the reference temperature Tbase. In the case where it is clear that the pressure has decreased to a certain level (for example, when the duration of the operation stop of the hydraulic excavator 1 is sufficiently long), in STEP5, Vall_c = Vall may be set.

  Next, in STEP 6, the oil amount information notification unit 34 determines whether or not the corrected total oil amount Vall_c is in a state where the total oil amount Vall_c is insufficient (whether the hydraulic oil needs to be replenished). It is compared with a predetermined determination reference value Vth for determining whether or not the total oil amount Vall_c is smaller than the determination reference value Vth. In other words, the processing of STEP 6 is the determination reference value (= Vth + δ (Toil) obtained by correcting the total oil amount Vall calculated in STEP 4 and the determination reference value Vth by the volume expansion amount δ (Toil). ) Is equivalent to the processing to be compared.

  When the determination result in STEP 6 is negative, the total oil amount Vall_c is an appropriate amount (is not insufficient). In this case, the process shown in the flowchart of FIG.

  On the other hand, if the determination result in STEP 6 is positive, the total oil amount Vall_c is insufficient. In this case, the oil amount information notifying unit 34 in STEP 7 includes hydraulic oil shortage information (in other words, information indicating that the hydraulic oil should be replenished) indicating that the hydraulic oil is insufficient, and hydraulic oil. The deficiency amount information indicating the deficiency amount ΔV (in other words, the required amount of hydraulic oil replenishment) is displayed on the display unit 45. In this case, the shortage amount ΔV is calculated, for example, as a value obtained by subtracting the calculated value of the total oil amount Vall_c obtained in STEP 5 from a value larger than the determination reference value Vth by a predetermined amount.

  The deficiency information is not limited to the numerical value of the deficiency ΔV. For example, the deficiency ΔV is information obtained by converting the deficiency ΔV into the amount of change in the liquid level or float height of the oil amount gauge 43 (for example, the oil amount gauge). 43) (information indicating the amount of change represented by a scale attached to 43).

  As described above, the hydraulic oil shortage information and the shortage amount information are displayed on the display 45, so that the driver of the excavator 1 should replenish the hydraulic tank 21 with hydraulic oil according to the display on the display 45. And the shortage amount ΔV of hydraulic oil can be recognized.

  In STEP 7, instead of visually informing the hydraulic oil shortage information and the shortage amount information on the display unit 45 or in addition to visual notification on the display unit 45, the hydraulic oil shortage information and the shortage amount information are displayed. You may make it alert | report by an audio | voice etc. auditorily.

  The oil amount information notification unit 34 further determines in STEP 8 whether there is a mobile terminal 50 that can communicate. If this determination result is negative, the processing shown in the flowchart of FIG. 4 is terminated.

  If the determination result in STEP 8 is affirmative, the oil amount information notification unit 34 executes terminal notification processing in STEP 9 for displaying the information on the hydraulic oil amount on the portable terminal 50 while sequentially updating the notification information.

  In this terminal notification process, the oil amount information notification unit 34 sequentially acquires the measurement value of the tank oil amount Vt at a predetermined control processing cycle via the tank oil amount measurement unit 33 and performs the processing of STEPs 4 and 5. By sequentially executing, the total oil amount Vall_c is calculated sequentially. Then, every time the total oil amount Vall_c is calculated, the oil amount information notification unit 34 performs the same determination process as STEP 6 on the new calculated value of the total oil amount Vall_c, and the determination result is affirmative. Then, the same or similar information as the hydraulic oil shortage information and the shortage amount information is transmitted to the portable terminal 50 and displayed on the portable terminal 50.

  And if the judgment result of the same judgment process as STEP6 becomes negative, the oil quantity information alerting | reporting part 34 will stop transmitting the same or similar information to the said hydraulic oil shortage information and shortage quantity information to the portable terminal 50. Then, the display of the information is terminated.

  By performing the terminal notification process as described above, an operator who replenishes hydraulic oil to the oil tank 21 confirms information to be displayed on the portable terminal 50, and supplies the hydraulic oil of the shortage amount ΔV to the oil tank 21. Replenishment can be performed smoothly.

  In STEP 9, in addition to displaying the same or similar information on the hydraulic oil shortage information and the shortage amount information on the portable terminal 50, or instead of displaying the information, an audible notification output by voice or the like is given to the portable terminal. 50 may occur.

  In the present embodiment, since the processing in the control device 30 is executed as described above, the hydraulic pressure does not depend on the operating state of each hydraulic cylinder 12 (in other words, regardless of the posture state of the working device 4). The notification information indicating the suitability of the amount of hydraulic oil held by the excavator 1 can be accurately output via the display 45 or the portable terminal 50. As a result, an operator or the like can appropriately confirm whether or not the amount of hydraulic oil is appropriate in a state where the working device 4 is arbitrarily stopped in a posture state.

  In addition, since the operator and the like can acquire the hydraulic oil shortage information and the shortage amount information through the portable terminal 50 possessed by the worker, the operator can check whether the hydraulic oil amount is appropriate near the inlet of the oil tank 21 or the like. it can. For this reason, when the amount of hydraulic oil is insufficient, the operation of quickly replenishing hydraulic oil to the oil tank 21 can be started.

  In addition, even during the operation of replenishing the hydraulic oil to the oil tank 21, the operator and the like can acquire the hydraulic oil shortage information and the shortage amount information in real time via the portable terminal 50, and thus easily recognize the completion timing of the replenishment work. And the replenishing operation can be performed efficiently.

  In addition, this invention is not limited to embodiment described above, Other embodiment can also be employ | adopted. Several other embodiments will be described below.

  In the above embodiment, whether or not the hydraulic oil amount of the excavator 1 is insufficient is determined in STEP 6 by comparing the total oil amount Vall_c, which is the sum of the tank oil amount Vt and the cylinder oil amount Vs, with the determination reference value Vth. Judgment was made. However, for example, it may be determined whether or not the amount of hydraulic oil is insufficient by the following method.

  That is, when the hydraulic oil amount of the hydraulic excavator 1 is an appropriate amount, the value of the tank oil amount (hereinafter referred to as the appropriate tank oil amount) is the cylinder oil amount Vsa, Vsb, Vsc in the current operating state of each hydraulic cylinder 12. Of the total cylinder oil amount (or a value obtained by correcting the estimated value according to the temperature Toil of the hydraulic oil) and the value of the total cylinder oil amount in the reference posture state of the working device 4 ( It is set according to the deviation from the (predetermined value). Then, the hydraulic oil amount of the excavator 1 is insufficient by comparing the measured value of the tank oil amount Vt (or a value obtained by correcting the measured value according to the temperature Toil of the hydraulic oil) with the set appropriate tank oil amount. It is determined whether or not it is in a state. Even in this case, the determination can be appropriately performed.

  In the embodiment, the oil amount information notifying unit 34 outputs the hydraulic oil shortage information and the shortage amount information as notification information when it is determined that the hydraulic oil amount of the excavator 1 is insufficient. I did it. However, for example, only one of the hydraulic oil shortage information and the shortage amount information may be output. Further, even when the hydraulic oil amount of the hydraulic excavator 1 is not insufficient, information indicating that may be output as notification information.

  Further, in addition to one or both of the hydraulic oil shortage information and the shortage amount information, or instead of one or both of the hydraulic oil shortage information and the shortage amount information, the total oil amount Vall_c (or Vall) and the determination reference value Vth. May be output as notification information.

  Moreover, in the said embodiment, the hydraulic excavator 1 shown in FIG. 1 was illustrated as a construction machine to which this invention is applied. However, the construction machine to which the present invention can be applied may be a construction machine having another structure. For example, in the construction machine, in addition to the three hydraulic cylinders 12a, 12b, and 12c described above, the hydraulic cylinder that swings the boom 11a in the yaw direction with respect to the swing body 3 or the boom 11a in the width direction of the swing body 3 is used. The excavator may include a hydraulic excavator including a hydraulic cylinder to be slid, a hydraulic excavator including an attachment including the hydraulic cylinder, a hydraulic excavator including a hydraulic cylinder for a dozer, or a hydraulic excavator including a wheel-type traveling body.

  The construction machine is not limited to a hydraulic excavator, and may be a construction machine such as a crane.

DESCRIPTION OF SYMBOLS 1 ... Hydraulic excavator (construction machine), 12a, 12b, 12c ... Hydraulic cylinder, 21 ... Oil tank, 30 ... Control apparatus (hydraulic oil amount measuring device), 31 ... Operation state information acquisition part, 32 ... Cylinder oil quantity estimation part 33 ... Tank oil amount measurement unit, 34 ... Oil amount information notification unit, 42 ... Temperature sensor, 50 ... Mobile terminal.

Claims (6)

An apparatus for measuring the amount of hydraulic oil in a construction machine comprising one or more hydraulic cylinders and an oil tank that stores hydraulic oil for driving the hydraulic cylinders,
An operation state information acquisition unit for acquiring operation state information indicating an operation state of the hydraulic cylinder;
A cylinder oil amount estimation unit that estimates a cylinder oil amount that is a hydraulic oil amount possessed by the hydraulic cylinder based on the operation state information;
A tank oil amount measuring unit for measuring a tank oil amount that is an amount of hydraulic oil stored in the oil tank;
An oil amount information notifying unit that outputs notification information regarding the appropriateness or degree of decrease of the hydraulic oil amount in the construction machine based on at least the estimated value of the cylinder oil amount and the measured value of the tank oil amount. A hydraulic oil measuring device for construction machinery. In the hydraulic oil amount measuring apparatus for construction machinery according to claim 1,
A temperature sensor that detects the temperature of the hydraulic oil stored in the oil tank;
The oil amount information notifying unit outputs the notification information based on the estimated value of the cylinder oil amount, the measured value of the tank oil amount, and the detected value of the temperature. A hydraulic oil amount measuring device for construction machinery, characterized in that it is configured. In the hydraulic oil amount measuring apparatus of the construction machine according to claim 1 or 2,
The oil amount information notifying unit has a function of determining whether or not the amount of hydraulic oil in the construction machine is insufficient based on at least the estimated value of the cylinder oil amount and the measured value of the tank oil amount. And when the said judgment result is affirmative, it is comprised so that the information which shows that may be output as said alerting | reporting information, The hydraulic-oil measuring device of the construction machine characterized by the above-mentioned. In the hydraulic oil amount measuring device for construction machinery according to claim 3,
When the determination result is affirmative, the notification information output by the oil amount information notification unit includes information indicating a deficiency in the amount of hydraulic oil in the construction machine. apparatus. In the hydraulic oil amount measuring apparatus of the construction machine according to any one of claims 1 to 4,
The oil amount information notifying unit is configured to have a function of outputting the notification information to a portable terminal outside the construction machine. In the apparatus for measuring the amount of hydraulic fluid of the construction machine according to claim 5,
The oil amount information notifying unit sequentially obtains the measured value of the tank oil amount while the operation of the construction machine is stopped, and outputs the information to the portable terminal according to the change in the measured value of the tank oil amount. A hydraulic oil amount measuring device for construction machinery, characterized in that it is configured to change information.