CONTROL CIRCUITRY AND CALIBRATION SYSTEM

Abstract

Control circuitry outputs a pump command current corresponding to an actuator operation signal to pump equipment including at least one pump whose displacement increases in accordance with increase in the pump command current. The control circuitry: stores calibration data generated based on actual measurement data of the at least one pump, the actual measurement data indicating an actual relationship between the pump command current and the displacement of the at least one pump, the calibration data being data to correct the pump command current such that the displacement of the at least one pump transitions on a performance line that is preset for the actuator operation signal. The control circuitry: determines the pump command current based on the actuator operation signal; and corrects the determined pump command current by using the calibration data, and outputs the corrected pump command current to the pump equipment.

Description

TECHNICAL FIELD

The present disclosure relates to control circuitry for pump equipment, and to a calibration system including the control circuitry.

BACKGROUND ART

In machines such as construction machines or industrial machines, there is a case where pump equipment including at least one pump whose displacement, i.e., a delivery amount per rotation, increases in accordance with increase in a pump command current is adopted as pump equipment to supply hydraulic oil to a hydraulic actuator (see Patent Literature 1, for example). In this case, the pump equipment is controlled by control circuitry, such that the displacement of the pump increases in accordance with increase in the moving speed of the hydraulic actuator.

Specifically, an actuator operation signal is inputted to the control circuitry. The actuator operation signal corresponds to an operating amount of an operator to move the hydraulic actuator. The operator is a device whose operating amount determines the moving speed of the hydraulic actuator. The control circuitry outputs a pump command current corresponding to the actuator operation signal to the pump equipment.

CITATION LIST

Patent Literature

PTL 1: Japanese Laid-Open Patent Application Publication No. 2019-210974

SUMMARY OF INVENTION

Technical Problem

Incidentally, each pump in the pump equipment varies in terms of I-q characteristics due to their individual differences. The I-q characteristics are a relationship between the pump command current and the displacement of the pump. Patent Literature 1 describes the following: a code that stores actual measurement data indicating actual I-q characteristics of the pump (although Patent Literature 1 describes “a relationship between the command current and the delivery flow rate”, the displacement can be obtained by dividing the delivery flow rate by the number of rotations) is displayed on the surface of the pump equipment, and by use of a code reader, the actual measurement data is inputted to the control circuitry for the pump equipment, and the variation in the I-q characteristics due to the individual differences is electronically calibrated by the control circuitry. Specifically, the control circuitry adjusts the pump command current outputted to the pump equipment, such that a preset displacement corresponding to an operating amount of the operator is obtained.

However, Patent Literature 1 does not give any specific description regarding how the control circuitry adjusts the pump command current based on the actual measurement data.

In view of the above, an object of the present disclosure is to provide control circuitry that realizes a method of adjusting the pump command current based on the actual measurement data, and to provide a calibration system including the control circuitry.

Solution to Problem

One aspect of the present disclosure provides control circuitry for outputting a pump command current corresponding to an actuator operation signal to pump equipment including at least one pump whose displacement increases in accordance with increase in the pump command current, the displacement of the at least one pump being a delivery amount per rotation of the at least one pump. The control circuitry: stores calibration data generated based on actual measurement data of the at least one pump, the actual measurement data indicating an actual relationship between the pump command current and the displacement of the at least one pump, the calibration data being data to correct the pump command current such that the displacement of the at least one pump transitions on a performance line that is preset for the actuator operation signal; determines the pump command current based on the actuator operation signal; and corrects the determined pump command current by using the calibration data, and outputs the corrected pump command current to the pump equipment.

Another aspect of the present disclosure provides control circuitry for outputting a pump command current corresponding to an actuator operation signal to pump equipment including at least one pump whose displacement increases in accordance with increase in the pump command current, the displacement of the at least one pump being a delivery amount per rotation of the at least one pump. The control circuitry: receives an input of actual measurement data of the at least one pump, the actual measurement data indicating an actual relationship between the pump command current and the displacement of the at least one pump, and stores the inputted actual measurement data; determines a pump command displacement based on the actuator operation signal; and determines the pump command current corresponding to the pump command displacement by using the actual measurement data, and outputs the determined pump command current to the pump equipment.

Yet another aspect of the present disclosure provides a calibration system including: pump equipment including at least one pump whose displacement increases in accordance with increase in a pump command current, the displacement of the at least one pump being a delivery amount per rotation of the at least one pump; at least one code displayed on a surface of the pump equipment, the at least one code storing actual measurement data of the at least one pump or save location information on the actual measurement data, the actual measurement data indicating an actual relationship between the pump command current and the displacement of the at least one pump; the above-described control circuitry, which receives an input of the actual measurement data; and a mobile terminal that obtains the actual measurement data by capturing an image of the at least one code and that transmits the obtained actual measurement data to the control circuitry via wireless communication.

Yet another aspect of the present disclosure provides a calibration system including: pump equipment including at least one pump whose displacement increases in accordance with increase in a pump command current, the displacement of the at least one pump being a delivery amount per rotation of the at least one pump; at least one code displayed on a surface of the pump equipment, the at least one code storing actual measurement data of the at least one pump or save location information on the actual measurement data, the actual measurement data indicating an actual relationship between the pump command current and the displacement of the at least one pump; the above-described control circuitry, which receives an input of the calibration data; and a mobile terminal that obtains the actual measurement data by capturing an image of the at least one code, generates the calibration data based on the obtained actual measurement data, and transmits the generated calibration data to the control circuitry via wireless communication.

Advantageous Effects of Invention

The present disclosure provides control circuitry that realizes a method of adjusting a pump command current based on actual measurement data, and provides a calibration system including the control circuitry.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows a schematic configuration of a calibration system including control circuitry according to Embodiment 1.

FIG. 2 shows a schematic configuration of a hydraulic system including pump equipment and the control circuitry.

FIG. 3 is a block diagram showing an internal configuration of the control circuitry.

FIG. 4 is a graph showing a relationship between an actuator operation signal and a pump displacement.

FIG. 5 is a graph showing a relationship between the actuator operation signal and a pump command current.

FIG. 6 is a graph showing a relationship between the pump command current and the pump displacement.

FIG. 7 shows calibration data.

FIG. 8 is a graph showing a relationship between a pump delivery pressure and the pump displacement in horsepower control.

FIG. 9 is a block diagram showing an internal configuration of control circuitry according to Embodiment 2.

DESCRIPTION OF EMBODIMENTS

Embodiment 1

FIG. 1 shows a calibration system 1, which includes pump equipment 2 and control circuitry 3 according to Embodiment 1 for the pump equipment 2. FIG. 2 shows a hydraulic system 10 including the pump equipment 2, a hydraulic actuator 8, and the control circuitry 3.

First, the hydraulic system 10 is described with reference to FIG. 2. The hydraulic system 10 is installed in, for example, a construction machine such as a hydraulic excavator or a hydraulic crane, or in an industrial machine such as a press machine.

The pump equipment 2 includes: at least one pump 21 of a variable displacement type; and at least one regulator 22, which changes the displacement of the corresponding pump 21. In the present embodiment, the pump equipment 2 includes two pumps 21 and two regulators 22. However, the number of pumps 21 included in the pump equipment 2 may be only one.

In the present embodiment, each pump 21 is a swash plate pump (axial piston pump). The pump equipment 2 may be of a parallel type, in which the center axes of the two respective pumps 21 are parallel to each other, or may be of a tandem type, in which the center axes of the two respective pumps 21 are coaxial with each other. Alternatively, the pump equipment 2 may include one or two bent axis pumps as the pump(s) 21.

In the present embodiment, the pump equipment 2 is driven by an engine 7. Both in the case where the pump equipment 2 is of a parallel type and in the case where it is of a tandem type, the pump equipment 2 includes one input shaft, and the input shaft is coupled to the output shaft of the engine 7. Alternatively, the pump equipment 2 may be driven by an electric motor.

Each regulator 22 receives an input of a pump command current I from the control circuitry 3. As shown in FIG. 6, a displacement q of each pump 21, which is a delivery amount per rotation of the pump 21, increases in accordance with increase in the pump command current I inputted to the corresponding regulator 22.

For example, the regulator 22 may change hydraulic pressure applied to a servo piston coupled to the swash plate of the pump 21 in accordance with the pump command current

I. In this case, in accordance with increase in the pump command current I, the servo piston shifts in such a direction as to increase the tilting angle of the swash plate. Alternatively, the regulator 22 may be an electric actuator coupled to the swash plate.

Each pump 21 supplies hydraulic oil to the hydraulic actuator 8. The number of hydraulic actuators 8 may be plural. In the present embodiment, the hydraulic actuator 8 is a double-acting cylinder or hydraulic motor that moves bi-directionally. Accordingly, the pump 21 is connected to a direction-switching valve 82 by a supply line 81, and the direction-switching valve 82 is connected to the hydraulic actuator 8 by a pair of supply/discharge lines 83.

A relief line is branched off from the supply line 81, and a relief valve is located on the relief line. An unloading line may be branched off from the supply line 81, and an unloading valve may be located on the unloading line. In a case where the number of hydraulic actuators 8 is plural and the unloading line is adopted, when none of the hydraulic actuators 8 is moved, i.e., when the supply line 81 is blocked by all the direction-switching valves 82, the unloading valve is opened, and the hydraulic oil delivered from the pump 21 is brought back to the tank through the unloading line.

The hydraulic system 10 further includes an operator 9, which is a device to move the hydraulic actuator 8. The operator 9 outputs an actuator operation signal S corresponding to an operating amount of the operator 9. In the present embodiment, the operator 9 is an electrical joystick that outputs an electrical signal as the actuator operation signal S. The actuator operation signal S outputted from the operator 9 is inputted to the control circuitry 3.

In a case where the hydraulic system 10 is installed in an unmanned machine, the operator 9 may be eliminated. In this case, the control circuitry 3 may generate the actuator operation signal S.

In the present embodiment, the aforementioned direction-switching valve 82 includes: a first pilot port to move the hydraulic actuator 8 in a first direction; and a second pilot port to move the hydraulic actuator 8 in a second direction. Solenoid proportional valves are connected to these pilot ports, respectively.

The control circuitry 3 controls the direction-switching valve 82 via the solenoid proportional valves, such that the opening area of the direction-switching valve 82 increases in accordance with increase in the operating amount of the operator 9. Accordingly, the moving speed of the hydraulic actuator 8 increases in accordance with increase in the operating amount of the operator 9.

Alternatively, the operator 9 may be a pilot operation valve that outputs a pilot pressure to the first pilot port or the second pilot port of the direction-switching valve 82. The pilot pressure outputted from the pilot operation valve increases in accordance with increase in the operating amount of the operator 9, which is the pilot operation valve. In a case where the operator 9 is a pilot operation valve, each pilot pressure outputted from the operator 9 is detected by a corresponding one of pressure sensors, and inputted to the control circuitry 3 as the actuator operation signal S. Alternatively, the direction-switching valve 82 may be a solenoid valve that is directly controlled by the control circuitry 3.

The control circuitry 3 outputs the pump command current I corresponding to the actuator operation signal S to the corresponding regulator 22 (i.e., the regulator 22 of the pump 21 that supplies the hydraulic oil to the hydraulic actuator 8 corresponding to the operator 9 that has been operated). In the present embodiment, the actuator operation signal S increases in accordance with increase in the operating amount of the operator 9. Also, as shown in FIG. 5, the pump command current I indicates a positive correlation with the actuator operation signal S. Accordingly, as shown in FIG. 4, the displacement q of the pump 21 increases in accordance with increase in the operating amount of the operator 9 (i.e., in accordance with increase in the actuator operation signal S).

In the present embodiment, the control circuitry 3 performs horsepower control to limit the displacement q of the pump 21, such that the load on the pump 21 does not exceed the output power of the engine 7. Accordingly, the control circuitry 3 is electrically connected to a rotation speed sensor 71 located on the engine 7 and a pressure sensor 84 located on the supply line 81. The rotation speed sensor 71 detects a rotation speed N of the engine 7, and the pressure sensor 84 detects a delivery pressure Pd of the pump 21. The detected rotation speed N and the detected delivery pressure Pd are inputted to the control circuitry 3. The horsepower control will be described below in detail together with calibration.

Next, described with reference to FIG. 1 and FIG. 3 is calibration that the control circuitry 3 performs to calibrate variation in I-q characteristics due to individual differences. The I-q characteristics are a relationship between the pump command current I and the displacement q.

Regarding the control circuitry 3, the functionality of the elements disclosed herein may be implemented using circuitry or processing circuitry which includes general purpose processors, special purpose processors, integrated circuits, ASICs (“Application Specific Integrated Circuits”), conventional circuitry and/or combinations thereof which are configured or programmed to perform the disclosed functionality. Processors are considered processing circuitry or circuitry as they include transistors and other circuitry therein. In the disclosure, the circuitry, units, or means are hardware that carry out or are programmed to perform the recited functionality. The hardware may be any hardware disclosed herein or otherwise known which is programmed or configured to carry out the recited functionality. When the hardware is a processor which may be considered a type of circuitry, the circuitry, means, or units are a combination of hardware and software, the software being used to configure the hardware and/or processor.

The calibration system 1 includes, in addition to the pump equipment 2 and the control circuitry 3, a mobile terminal 5, which is communicable with the control circuitry 3 via wireless communication. In the present embodiment, a wireless LAN router 4 is wire-connected to the control circuitry 3, and the mobile terminal 5 performs wireless communication with the wireless LAN router 4. Alternatively, the control circuitry 3 may include a wireless communicator, and the mobile terminal 5 may directly perform wireless communication with the control circuitry 3.

On the surface of the pump equipment 2, two codes 6 corresponding to two respective pumps 21 are displayed. In a case where the pump equipment 2 includes only one pump 21, the number of codes 6 displayed on the surface of the pump equipment 2 is also one. Alternatively, one code 6 may store below-described actual measurement data of the two pumps 21.

For the display of each code 6 on the surface of the pump equipment 2, the code 6 may be printed on a plate, and the plate may be mounted to the pump equipment 2. Alternatively, the code 6 may be directly printed on the surface of the pump equipment 2.

Each code 6 stores actual measurement data that indicates actual I-q characteristics of the corresponding pump 21. For example, the code 6 is a matrix two-dimensional code (QR code (registered trademark)).

The mobile terminal 5 includes a camera that can capture an image of each code 6. As a result of the camera capturing an image of each code 6, the mobile terminal 5 obtains actual measurement data of the corresponding pump 21, which is stored in the code 6. The mobile terminal 5 transmits the obtained actual measurement data to the control circuitry 3 via wireless communication and the wireless LAN router 4. As a result, the actual measurement data of the two pumps 21 is inputted to the control circuitry 3.

The control circuitry 3 stores therein the inputted actual measurement data of each pump 21. Then, for each pump 21, the control circuitry 3 generates calibration data shown in FIG. 7 based on the stored actual measurement data, and stores the generated calibration data. The calibration data is data to correct the pump command current I such that the displacement q of the pump 21 transitions on a performance line L (see FIG. 4), which is preset for the actuator operation signal S. The calibration data may be a map as shown in FIG. 7, or may be a mathematical function or a mathematical formula. In FIG. 4, of the performance line L, a transition portion from the minimum displacement to the maximum displacement is a straight line. Alternatively, the transition portion may be a convex upward curve or convex downward curve.

Regarding the calibration, to be more specific, the control circuitry 3 determines the pump command current I based on the actuator operation signal S. In the present embodiment, the control circuitry 3 performs the horsepower control as described above. Therefore, as shown in FIG. 3, first, the control circuitry 3 determines an actuator operation command current Ia in accordance with the actuator operation signal S, and determines a horsepower control command current Ib based on the rotation speed N of the engine 7 and the delivery pressure Pd of the pump 21.

Regarding the determination of the actuator operation command current Ia, for example, the actuator operation command current Ia is determined by using a map (alternatively a mathematical function or a mathematical formula) that defines a correspondence relationship between the actuator operation signal S and the actuator operation command current Ia, such as one represented by a solid line in FIG. 5.

Regarding the determination of the horsepower control command current Ib, the control circuitry 3 prestores, for each of different rotation speeds of the engine 7, a map (alternatively a mathematical function or a mathematical formula) that defines the upper limit value of the displacement q of the pump 21 in relation to the delivery pressure Pd of the pump 21 as shown in FIG. 8. First, the control circuitry 3 uses the map to determine the upper limit value of the displacement q of the pump 21 from the rotation speed N of the engine 7 and the delivery pressure Pd of the pump 21. Thereafter, from the determined upper limit value, the control circuitry 3 determines the horsepower control command current Ib by using a map (alternatively a mathematical function or a mathematical formula) that defines a correspondence relationship between the displacement q and the pump command current I, such as one represented by a solid line in FIG. 6.

Then, the control circuitry 3 determines a smaller one of the determined actuator operation command current Ia or the determined horsepower control command current Ib as the pump command current I. Thereafter, the control circuitry 3 corrects the determined pump command current I by using the calibration data shown in FIG. 7, and outputs the corrected pump command current I to the corresponding regulator 22.

For example, assume that, as represented by a dashed line in FIG. 6, the actual I-q characteristics of the pump 21 (i.e., the actual measurement data) deviate from design characteristics represented by a solid line in FIG. 6. In this case, if the pump command current I is determined such that it is proportional to the actuator operation signal S as represented by the solid line in FIG. 5, then the displacement q of the pump 21 in relation to the actuator operation signal S transitions on a line that deviates from the preset performance line L as represented by a dashed line in FIG. 4.

In this respect, by correcting the pump command current I by using the calibration data shown in FIG. 7, the displacement q of the pump 21 in relation to the actuator operation signal S can be made transition on the preset performance line L. That is, the pump command current I in relation to the actuator operation signal S is corrected as represented by a two-dot chain line in FIG. 5.

As described above, in the control circuitry 3 of the present embodiment, since the pump command current I determined based on the actuator operation signal S is corrected by using the calibration data generated based on the actual measurement data, variation in I-q characteristics due to individual differences can be calibrated electronically. That is, this calibration realizes a method of adjusting the pump command current I based on the actual measurement data.

Further, in the present embodiment, since a smaller one of the actuator operation command current Ia or the horsepower control command current Ib is determined as the pump command current I, even in a case where the displacement q of the pump 21 is limited by the horsepower control, variation in I-q characteristics due to individual differences can be calibrated electronically.

Still further, in the present embodiment, since the actual measurement data is transmitted from the mobile terminal 5 to the control circuitry 3 via wireless communication, by installing a special program on a commercially available mobile terminal, the actual measurement data can be transmitted to the control circuitry 3 by utilizing the mobile terminal. Accordingly, it is unnecessary to use a code reader or the like that is wire-connected to the control circuitry 3.

<Variations>

In the above-described embodiment, the control circuitry 3 generates the calibration data. Instead, the mobile terminal 5 may generate the calibration data based on the actual measurement data, and transmit the generate calibration data to the control circuitry 3 via wireless communication and the wireless LAN router 4. That is, the calibration data may be inputted to the control circuitry 3, and the control circuitry 3 may store the inputted calibration data.

According to the above configuration, by installing a special program on a commercially available mobile terminal, the calibration data can be transmitted to the control circuitry 3 by utilizing the mobile terminal.

Embodiment 2

Next, with reference to FIG. 9, control circuitry 3A according to Embodiment 2 is described. Although the description below is given on the assumption that the pump equipment 2 (see FIG. 1) includes one pump 21, the number of pumps 21 included in the pump equipment 2 may be two.

In the present embodiment, similar to Embodiment 1, actual measurement data indicating the actual I-q characteristics of each pump 21 is transmitted from the mobile terminal 5 (see FIG. 1) to the control circuitry 3A. In this manner, the actual measurement data of the pump 21 is inputted to the control circuitry 3A. The control circuitry 3 stores the inputted actual measurement data of the pump 21 as an I-q map (alternatively as a mathematical function or a mathematical formula).

Further, similar to Embodiment 1, the actuator operation signal S, the rotation speed N of the engine 7, and the delivery pressure Pd of the pump 21 are inputted to the control circuitry 3A.

The control circuitry 3A determines a pump command displacement qi based on the actuator operation signal S. In the present embodiment, in order for the control circuitry 3A to perform the horsepower control, first, the control circuitry 3A determines an actuator operation command displacement qa in accordance with the actuator operation signal S, and determines a horsepower control command displacement qb based on the rotation speed N of the engine 7 and the delivery pressure Pd of the pump 21.

Regarding the determination of the actuator operation command displacement qa, a map (alternatively a mathematical function or a mathematical formula) that defines a correspondence relationship between the actuator operation signal S and the actuator operation command displacement qa is used to determine the actuator operation command displacement qa.

Regarding the determination of the horsepower control command displacement qb, the control circuitry 3A prestores, for each of different rotation speeds of the engine 7, a map (alternatively a mathematical function or a mathematical formula) that defines the upper limit value of the displacement q of the pump 21 in relation to the delivery pressure Pd of the pump 21 as shown in FIG. 8. The control circuitry 3A uses the map to determine the upper limit value of the displacement q of the pump 21 from the rotation speed N of the engine 7 and the delivery pressure Pd of the pump 21, and determines the upper limit value as the horsepower control command displacement qb.

Then, the control circuitry 3A determines a smaller one of the determined actuator operation command displacement qa or the determined horsepower control command displacement qb as the pump command displacement qi. Thereafter, the control circuitry 3A uses the stored I-q map (i.e., actual measurement data) to determine the pump command current I corresponding to the pump command displacement qi, and outputs the determined pump command current I to the regulator 22.

In the present embodiment, since the pump command current I corresponding to the pump command displacement qi determined based on the actuator operation signal S is determined by using the actual measurement data, variation in I-q characteristics due to individual differences can be calibrated electronically. That is, this calibration realizes a method of adjusting the pump command current I based on the actual measurement data.

Further, in the present embodiment, since a smaller one of the actuator operation command displacement qa or the horsepower control command displacement qb is determined as the pump command displacement qi, even in a case where the displacement q of the pump 21 is limited by the horsepower control, variation in I-q characteristics due to individual differences can be calibrated electronically.

Other Embodiments

The present disclosure is not limited to the above-described embodiment. Various modifications can be made without departing from the scope of the present disclosure.

For example, both in Embodiment 1 and Embodiment 2, instead of storing the actual measurement data of the pump 21, the code 6 may store save location information on the actual measurement data. The save location information is, for example, the IP (Internet Protocol) address of a server that is the save location, or the URL (Uniform Resource Locator) of a particular hierarchy level of the server. In this case, when the camera has captured an image of the code 6, the mobile terminal 5 obtains, from the server specified by the save location information, the actual measurement data saved in the server via the Internet. Also, in the case where the code 6 stores the save location information on the actual measurement data, the code 6 may be a character string.

In a case where the minimum displacement of the pump 21 is zero and the hydraulic actuator 8 is a single-acting cylinder, the direction-switching valve 82 may be eliminated. In this case, the moving speed of the hydraulic actuator 8 is changed only by the displacement of the pump 21.

Both in Embodiment 1 and Embodiment 2, the horsepower control can be eliminated. In this case, in Embodiment 1, the control circuitry 3 may directly determine the pump command current I in accordance with the actuator operation signal S, and in Embodiment 2, the control circuitry 3A may directly determine the pump command displacement qi in accordance with the actuator operation signal S.

Summary

One aspect of the present disclosure provides control circuitry for outputting a pump command current corresponding to an actuator operation signal to pump equipment including at least one pump whose displacement increases in accordance with increase in the pump command current, the displacement of the at least one pump being a delivery amount per rotation of the at least one pump. The control circuitry: stores calibration data generated based on actual measurement data of the at least one pump, the actual measurement data indicating an actual relationship between the pump command current and the displacement of the at least one pump, the calibration data being data to correct the pump command current such that the displacement of the at least one pump transitions on a performance line that is preset for the actuator operation signal; determines the pump command current based on the actuator operation signal; and corrects the determined pump command current by using the calibration data, and outputs the corrected pump command current to the pump equipment.

According to the above configuration, since the pump command current determined based on the actuator operation signal is corrected by using the calibration data generated based on the actual measurement data, variation in I-q characteristics (a relationship between the pump command current and the displacement) due to individual differences can be calibrated electronically. That is, this calibration realizes a method of adjusting the pump command current based on the actual measurement data.

The above control circuitry may: determine an actuator operation command current in accordance with the actuator operation signal; receive an input of a rotation speed of an engine that drives the pump equipment and an input of a delivery pressure of the at least one pump, and determine a horsepower control command current based on the rotation speed and the delivery pressure; and determine a smaller one of the actuator operation command current or the horsepower control command current as the pump command current. According to this configuration, even in a case where the displacement of the pump is limited by horsepower control, variation in I-q characteristics due to individual differences can be calibrated electronically.

For example, the above control circuitry may receive an input of the actual measurement data, store the inputted actual measurement data, generate the calibration data based on the stored actual measurement data, and store the generated calibration data.

The above control circuitry may receive an input of the calibration data, and store the inputted calibration data. According to this configuration, it is not necessary for the control circuitry to generate the calibration data.

Another aspect of the present disclosure provides control circuitry for outputting a pump command current corresponding to an actuator operation signal to pump equipment including at least one pump whose displacement increases in accordance with increase in the pump command current, the displacement of the at least one pump being a delivery amount per rotation of the at least one pump. The control circuitry: receives an input of actual measurement data of the at least one pump, the actual measurement data indicating an actual relationship between the pump command current and the displacement of the at least one pump, and stores the inputted actual measurement data; determines a pump command displacement based on the actuator operation signal; and determines the pump command current corresponding to the pump command displacement by using the actual measurement data, and outputs the determined pump command current to the pump equipment.

According to the above configuration, since the pump command current corresponding to the pump command displacement determined based on the actuator operation signal is determined by using the actual measurement data, variation in I-q characteristics due to individual differences can be calibrated electronically. That is, this calibration realizes a method of adjusting the pump command current based on the actual measurement data.

The control circuitry may: determine an actuator operation command displacement corresponding to the actuator operation signal; receive an input of a rotation speed of an engine that drives the pump equipment and an input of a delivery pressure of the at least one pump, and determine a horsepower control command displacement based on the rotation speed and the delivery pressure; and determine a smaller one of the actuator operation command displacement or the horsepower control command displacement as the pump command displacement. According to this configuration, even in a case where the displacement of the pump is limited by horsepower control, variation in I-q characteristics due to individual differences can be calibrated electronically.

Yet another aspect of the present disclosure provides a calibration system including: pump equipment including at least one pump whose displacement increases in accordance with increase in a pump command current, the displacement of the at least one pump being a delivery amount per rotation of the at least one pump; at least one code displayed on a surface of the pump equipment, the at least one code storing actual measurement data of the at least one pump or save location information on the actual measurement data, the actual measurement data indicating an actual relationship between the pump command current and the displacement of the at least one pump; the above-described control circuitry, which receives an input of the actual measurement data; and a mobile terminal that obtains the actual measurement data by capturing an image of the at least one code and that transmits the obtained actual measurement data to the control circuitry via wireless communication.

According to the above configuration, since the actual measurement data is transmitted from the mobile terminal to the control circuitry via wireless communication, by installing a special program on a commercially available mobile terminal, the actual measurement data can be transmitted to the control circuitry by utilizing the mobile terminal. Accordingly, it is unnecessary to use a code reader or the like that is wire-connected to the control circuitry.

Yet another aspect of the present disclosure provides a calibration system including: pump equipment including at least one pump whose displacement increases in accordance with increase in a pump command current, the displacement of the at least one pump being a delivery amount per rotation of the at least one pump; at least one code displayed on a surface of the pump equipment, the at least one code storing actual measurement data of the at least one pump or save location information on the actual measurement data, the actual measurement data indicating an actual relationship between the pump command current and the displacement of the at least one pump; the above-described control circuitry, which receives an input of the calibration data; and a mobile terminal that obtains the actual measurement data by capturing an image of the at least one code, generates the calibration data based on the obtained actual measurement data, and transmits the generated calibration data to the control circuitry via wireless communication.

According to the above configuration, since the calibration data is generated by the mobile terminal and the generated calibration data is transmitted from the mobile terminal to the control circuitry via wireless communication, by installing a special program on a commercially available mobile terminal, the calibration data can be transmitted to the control circuitry by utilizing the mobile terminal.

For example, the at least one pump may include two pumps. The at least one code may include two codes corresponding to the respective two pumps. Each code may store the actual measurement data of the corresponding pump or save location information on the actual measurement data.

Claims

1. Control circuitry for outputting a pump command current corresponding to an actuator operation signal to pump equipment including at least one pump whose displacement increases in accordance with increase in the pump command current, the displacement of the at least one pump being a delivery amount per rotation of the at least one pump, the control circuitry: stores calibration data generated based on actual measurement data of the at least one pump, the actual measurement data indicating an actual relationship between the pump command current and the displacement of the at least one pump, the calibration data being data to correct the pump command current such that the displacement of the at least one pump transitions on a performance line that is preset for the actuator operation signal;determines the pump command current based on the actuator operation signal; andcorrects the determined pump command current by using the calibration data, and outputs the corrected pump command current to the pump equipment.

2. The control circuitry according to claim 1, wherein the control circuitry: determines an actuator operation command current in accordance with the actuator operation signal;receives an input of a rotation speed of an engine that drives the pump equipment and an input of a delivery pressure of the at least one pump, and determines a horsepower control command current based on the rotation speed and the delivery pressure; anddetermines a smaller one of the actuator operation command current or the horsepower control command current as the pump command current.

3. The control circuitry according to claim 1, wherein the control circuitry receives an input of the actual measurement data, stores the inputted actual measurement data, generates the calibration data based on the stored actual measurement data, and stores the generated calibration data.

4. The control circuitry according to claim 1, wherein the control circuitry receives an input of the calibration data, and stores the inputted calibration data.

5. Control circuitry for outputting a pump command current corresponding to an actuator operation signal to pump equipment including at least one pump whose displacement increases in accordance with increase in the pump command current, the displacement of the at least one pump being a delivery amount per rotation of the at least one pump, the control circuitry: receives an input of actual measurement data of the at least one pump, the actual measurement data indicating an actual relationship between the pump command current and the displacement of the at least one pump, and stores the inputted actual measurement data;determines a pump command displacement based on the actuator operation signal; anddetermines the pump command current corresponding to the pump command displacement by using the actual measurement data, and outputs the determined pump command current to the pump equipment.

6. The control circuitry according to claim 5, wherein the control circuitry: determines an actuator operation command displacement corresponding to the actuator operation signal;receives an input of a rotation speed of an engine that drives the pump equipment and an input of a delivery pressure of the at least one pump, and determines a horsepower control command displacement based on the rotation speed and the delivery pressure; anddetermines a smaller one of the actuator operation command displacement or the horsepower control command displacement as the pump command displacement.

7. A calibration system comprising: pump equipment including at least one pump whose displacement increases in accordance with increase in a pump command current, the displacement of the at least one pump being a delivery amount per rotation of the at least one pump;at least one code displayed on a surface of the pump equipment, the at least one code storing actual measurement data of the at least one pump or save location information on the actual measurement data, the actual measurement data indicating an actual relationship between the pump command current and the displacement of the at least one pump;the control circuitry according to claim 3; anda mobile terminal that obtains the actual measurement data by capturing an image of the at least one code and that transmits the obtained actual measurement data to the control circuitry via wireless communication.

8. A calibration system comprising: pump equipment including at least one pump whose displacement increases in accordance with increase in a pump command current, the displacement of the at least one pump being a delivery amount per rotation of the at least one pump;at least one code displayed on a surface of the pump equipment, the at least one code storing actual measurement data of the at least one pump or save location information on the actual measurement data, the actual measurement data indicating an actual relationship between the pump command current and the displacement of the at least one pump;the control circuitry according to claim 4; anda mobile terminal that obtains the actual measurement data by capturing an image of the at least one code, generates the calibration data based on the obtained actual measurement data, and transmits the generated calibration data to the control circuitry via wireless communication.

9. The calibration system according to claim 7, wherein the at least one pump includes two pumps,the at least one code includes two codes corresponding to the respective two pumps, andeach code stores the actual measurement data of the corresponding pump or save location information on the actual measurement data.

10. A calibration system comprising: pump equipment including at least one pump whose displacement increases in accordance with increase in a pump command current, the displacement of the at least one pump being a delivery amount per rotation of the at least one pump;at least one code displayed on a surface of the pump equipment, the at least one code storing actual measurement data of the at least one pump or save location information on the actual measurement data, the actual measurement data indicating an actual relationship between the pump command current and the displacement of the at least one pump;the control circuitry according to claim 5; anda mobile terminal that obtains the actual measurement data by capturing an image of the at least one code and that transmits the obtained actual measurement data to the control circuitry via wireless communication.

11. The calibration system according to claim 10, wherein the at least one pump includes two pumps,the at least one code includes two codes corresponding to the respective two pumps, andeach code stores the actual measurement data of the corresponding pump or save location information on the actual measurement data.

12. The calibration system according to claim 8, wherein the at least one pump includes two pumps,the at least one code includes two codes corresponding to the respective two pumps, andeach code stores the actual measurement data of the corresponding pump or save location information on the actual measurement data.