JP5964116B2 - Work vehicle - Google Patents

Description

  The present invention relates to a work vehicle including a work device that can be driven by power or electric power of an engine.

  2. Description of the Related Art Conventionally, as this type of work vehicle, a vehicle equipped with a working device that can be driven by hydraulic oil discharged from a hydraulic pump that is driven by the power of an engine and that can be driven by electric power is known.

  The work vehicle includes a power battery for supplying electric power for driving the work device, in addition to the vehicle battery for supplying electric power used on the vehicle side.

  In the work vehicle, when the work device is driven by the power of the engine, there is known one that charges the power battery with the power generated by the power of the actuator driven by the hydraulic oil discharged from the hydraulic pump (for example, , See Patent Document 1).

JP 2007-119179 A

  In the work vehicle, since the power battery cannot be charged when the load at the time of driving the work device is large or during traveling of the vehicle, the work battery is insufficiently charged and the work device can be electrically driven. There are cases where it is not possible.

  An object of the present invention is to provide a work vehicle that can reliably charge a power battery with electric power for driving a work device.

In order to achieve the above object, the present invention provides a vehicle that is driven by engine power, a working device that can be driven by hydraulic oil discharged from a hydraulic pump that is driven by engine power, and that can be driven by electric power. , A first generator that generates power by the power of the engine, a second generator that generates power by the power of an actuator driven by hydraulic oil discharged from the hydraulic pump, and the first generator Is provided so as to be able to store the electric power generated in the vehicle, capable of supplying electric power used on the vehicle side, and provided so as to be able to store the electric power generated in the first generator and the electric power generated in the second generator. , and a power battery capable of supplying electric power when driving the working device by power, electric power generated in the first generator Is preferentially supplied as electric power for charging the vehicle battery, it is supplied as the power surplus power to charge the power battery.

  As a result, the power battery is charged by the first generator that generates power with the power of the engine, and is charged by the second generator that generates power by the hydraulic oil discharged from the hydraulic pump. The power battery is charged by the electric power generated by the first generator during the engine driving operation of the device, and the power battery can be charged by the electric power generated by the second generator when the load of the driving unit of the working device is small. It becomes.

  According to the present invention, the electric power generated by the first generator is charged to the power battery while the vehicle is running or the working device is driven by the engine, and the second power generation is performed when the load on the driving unit of the working device is small. Since the electric power generated by the machine can be charged to the power battery, the electric power for electrically driving the work device can be reliably charged to the power battery, and the power shortage when the work device is driven by the electric motor can be prevented. .

It is a side view of the mobile crane which shows one Embodiment of this invention. It is a schematic block diagram of a hydraulic pressure supply apparatus. It is a flowchart which shows a circuit switching process. It is a schematic block diagram of the hydraulic supply apparatus which shows other embodiment of this invention.

  1 to 3 show an embodiment of the present invention.

  As shown in FIG. 1, a mobile crane 1 as a work vehicle according to the present invention includes a traveling vehicle 10 and a crane device 20.

  The vehicle 10 has wheels 11 and travels using the engine E as a power source. Further, on both the left and right sides of the front side and the rear side of the vehicle 10, there are provided outriggers 12 for preventing the vehicle 10 from overturning during crane operation and for stably supporting the vehicle 10. The outrigger 12 can move outward in the width direction, and can extend downward by a hydraulic jack cylinder 13 (FIG. 2). The outrigger 12 stably supports the vehicle 10 with respect to the ground by grounding the lower end.

  The crane apparatus 20 includes a swivel base 21 that is turnable on a horizontal plane at a substantially central portion in the front-rear direction of the vehicle 10, a boom 22 that is provided so as to be able to rise and fall with respect to the swivel base 21, and is extendable. The wire rope 23 suspended from the distal end side of the boom 22, the winch 24 for winding or unwinding the wire rope 23, and the front side of the swivel base 21 are related to the traveling of the vehicle 10 and the work by the crane device 20. And a driving cab 25 for performing an operation.

  The swivel base 21 is provided so as to be turnable with respect to the vehicle 10 via a ball bearing type or roller bearing type turning circle 21a, and is turned by a hydraulic turning motor 21b (FIG. 2).

  The boom 22 includes a plurality of boom members 22a, 22b, 22c, and 22d. The boom members 22b, 22c, and 22d that are adjacent to the distal end side inside the boom members 22a, 22b, and 22c excluding the boom member 22d on the most advanced side. Is configured to be telescopic. The base end portion of the most proximal end boom member 22 a is swingably connected to the bracket 21 c of the swivel base 21. A hydraulic hoisting cylinder 22e is connected between the boom member 22a and the bracket 21c, and the boom 22 is hoisted by an expansion and contraction operation of the hoisting cylinder 22e. A hydraulic telescopic cylinder 22f (FIG. 2) is provided inside the boom member 22a on the most proximal end side, and the boom 22 is expanded and contracted by the expansion and contraction of the expansion cylinder 22f.

  The wire rope 23 is provided with a hook block 23 a on the distal end side, and the hook block 23 a is suspended from the distal end portion of the boom 22. A suspended load can be locked to the hook block 23 a, and the suspended load locked to the hook block 23 a is suspended from the tip of the boom 22.

  The winch 24 has a drum 24a around which the wire rope 23 is wound, and the drum 24a is configured to be rotatable forward and backward by a hydraulic winch motor 24b (FIG. 2).

  The driving cab 25 is provided on the side of the bracket 21 c on the turntable 21 and turns together with the turntable 21.

  Actuators such as each jack cylinder 13, turning motor 21 b, hoisting cylinder 22 e, telescopic cylinder 22 f and winch motor 24 b operate by supplying or discharging hydraulic oil. The hydraulic oil that operates each actuator is supplied by a hydraulic pressure supply device 30 shown in FIG.

  The hydraulic pressure supply device 30 includes a PTO (power take-off) mechanism 31 for taking out the power of the engine E for traveling the vehicle 10, a first hydraulic pump 32 driven by the power of the engine E taken out by the PTO mechanism 31, and a PTO A second hydraulic pump 33 that is driven by the power of the engine E without passing through the mechanism 31, a hydraulic motor 34 that can be driven by hydraulic oil discharged from the second hydraulic pump 33, and a power battery 35 for supplying electric power. The electric motor 36 driven by the power of the power battery 35, the third hydraulic pump 37 driven by the power of the electric motor 36, the first generator 38 driven by the power of the engine E, and the power of the hydraulic motor 34 The second generator 39 to be driven and the hydraulic oil discharged from the first hydraulic pump 32 or the third hydraulic pump 37 A control valve unit 40 for controlling the record, includes a, which are connected to the hydraulic oil circuit 41.

  The first hydraulic pump 32 is configured to be able to switch between transmission of power of the engine E and interruption of transmission of power by the PTO mechanism 31. The first hydraulic pump 32 is driven when the crane device 20 is operated by the power of the engine E.

  The second hydraulic pump 33 is directly connected to the engine E, and power is always transmitted when the engine E is driven. The second hydraulic pump 33 does not supply hydraulic oil to each jack cylinder 13, swing motor 21 b, hoisting cylinder 22 e, telescopic cylinder 22 f, and winch motor 24 b, but the hydraulic motor 34 and, for example, air conditioning in the driving cab 25. The hydraulic fluid is supplied to an actuator for driving the compressor and attaching / detaching the auxiliary jib.

  The first generator 38 mainly generates electric power used on the vehicle 10 side, such as starting of the engine E and lights of the vehicle 10. The first generator 38 is connected to a vehicle battery 38a for storing electric power used on the vehicle 10 side, and the vehicle battery 38a is charged by the electric power generated by the first generator 38. . Furthermore, the 1st generator 38 is connected to the power battery 35 via the battery charger 38b, and the power battery 35 is charged with the surplus electric power at the time of charging the vehicle battery 38a.

  The second generator 39 generates electric power that drives the third hydraulic pump 37. A power battery 35 is connected to the second generator 39, and the power battery 35 is charged by the electric power generated by the second generator 39.

  The control valve unit 40 has a plurality of control valves corresponding to the respective actuators, and each control valve can be operated by an operation unit 40a such as an operation lever or an operation pedal. Each control valve constituting the control valve unit 40 has switching means such as a solenoid and can be operated by a signal from an overload prevention device described later.

  In the hydraulic oil circuit 41, the suction sides of the first hydraulic pump 32, the second hydraulic pump 33, and the third hydraulic pump 37 are connected in parallel to the hydraulic oil tank 42. The discharge sides of the first hydraulic pump 32 and the third hydraulic pump 37 are connected to the pump side port of the control valve unit 40. In the hydraulic oil flow path between the discharge side of each of the first hydraulic pump 32 and the third hydraulic pump 37 and the control valve unit 40, the hydraulic oil from the discharge side of the first hydraulic pump 32 and the third hydraulic pump 37 is provided. A check valve 43 is provided for restricting the inflow. Each actuator is connected to the control valve unit 40. A hydraulic oil tank 42 is connected to a port on the hydraulic oil tank 42 side of the control valve unit 40 via a return filter 44.

  A hydraulic motor 34 and a bypass passage 45 are connected in parallel to the discharge side of the second hydraulic pump 33 in the hydraulic oil circuit 41, and the discharge side of the second hydraulic pump 33 is connected to the hydraulic motor 34 side by the direction switching valve 46. The flow path or the bypass flow path 45 is switched. The hydraulic motor 34 side flow passage and the hydraulic oil outflow side of the bypass flow passage 45 are connected to an actuator (not shown) for driving the air conditioning compressor, attaching / detaching the auxiliary jib, and the like.

  Further, as shown in FIG. 2, the mobile crane 1 includes a controller 50 for performing control related to operation of the hydraulic pressure supply device 30 and charging of the power battery 35.

  The controller 50 has a CPU, a ROM, and a RAM. When the controller 50 receives an input signal from a device connected to the input side, the CPU reads a program stored in the ROM based on the input signal, and stores a state detected by the input signal in the RAM. The output signal is transmitted to a device connected to the output side.

  As shown in FIG. 2, the controller 50 includes a power battery 35, a direction switching valve 46, a first current detection unit 51 for detecting a charging current value from the battery charger 38 b, and a second generator 39. The second current detector 52 for detecting the charging current value of the load, the load of the suspended load, the length of the boom 22 and the undulation angle are detected to calculate the rated load of the suspended load, and the load of the suspended load is rated. An overload prevention device 53 for stopping the operation of the crane device 20 when the load is exceeded is connected.

  In the mobile crane as the work vehicle configured as described above, at the time of crane work by the crane device 20, engine-driven crane work that performs crane work while driving the first hydraulic pump 32 by the power of the engine E, or engine It is possible to select an electrically driven crane operation in which the crane operation is performed while E is stopped and the third hydraulic pump 37 is driven by the power of the electric motor 36.

  Further, during the traveling of the vehicle 10 or during the engine-driven crane operation, the first generator 38 is driven by the power of the engine E, so that the first generator 38 generates power. The electric power generated by the first generator 38 is used on the vehicle 10 side, such as a light of the vehicle 10, and the vehicle battery 38a is preferentially charged by the battery charger 38b, and surplus power is charged to the power battery 35. Is done. At this time, when the amount of electric power used for charging the vehicle 10 side and the vehicle battery 38a is large, the amount of electric power charged in the power battery 35 decreases or the charging of the power battery 35 is stopped.

  In addition, the second hydraulic pump 33 is driven by the power of the engine E while the vehicle 10 is traveling or during engine-driven crane work. The hydraulic oil discharged by driving the second hydraulic pump 33 drives an actuator for driving the air conditioning compressor, attaching / detaching the auxiliary jib, and the like, and sets the direction switching valve 46 to the hydraulic motor 34 side. To drive the hydraulic motor 34. While the hydraulic motor 34 is being driven, the second generator 39 is driven by the power of the hydraulic motor 34, so the second generator 39 generates power. The electric power generated by the second generator 39 is charged in the power battery 35.

  While the engine E is being driven, the direction switching valve 46 is switched based on the voltage of the power battery 35, the detection current of the first current detection unit 51 and the detection current of the second current detection unit 52, and the second generator 39 Switch between power generation and power generation stop.

  Further, during the driving of the engine E, a circuit switching process for switching the direction switching valve 46 according to the load of the actuator driven by the hydraulic oil discharged from the second hydraulic pump 33 and the remaining amount of power of the power battery 35 is performed. . The operation of the controller 50 at this time will be described with reference to the flowchart of FIG.

(Step S1)
In step S1, the CPU determines whether or not the engine E is being driven. If it is determined that the engine E is being driven, the process proceeds to step S2, and if it is not determined that the engine E is being driven, the circuit switching process is terminated.

(Step S2)
When it is determined in step S1 that the engine E is being driven, in step S2, the CPU determines whether the load of the actuator driven by the hydraulic oil discharged from the second hydraulic pump 33 is equal to or less than a predetermined value. If the load of the actuator driven by the hydraulic oil discharged from the second hydraulic pump 33 is less than or equal to a predetermined value, the process proceeds to step S3, and the load of the actuator driven by the hydraulic oil discharged from the second hydraulic pump 33 is predetermined. If it is not determined that it is the following, the process proceeds to step S5.
Here, the load of the actuator driven by the hydraulic oil discharged from the second hydraulic pump 33 is the second hydraulic pressure necessary for driving the actuator for driving the air conditioning compressor, attaching / detaching the auxiliary jib, and the like. This is the magnitude of the output of the pump 33.

(Step S3)
If it is determined in step S2 that the load of the actuator driven by the hydraulic oil discharged from the second hydraulic pump 33 is equal to or less than a predetermined value, the CPU in step S3 determines that the remaining amount of power of the power battery 35 is equal to or less than a predetermined amount. It is determined whether or not there is. When it is determined that the remaining amount of power of the power battery 35 is less than or equal to the predetermined amount, the process proceeds to step S4, and when it is not determined that the remaining amount of power of the power battery 35 is less than or equal to the predetermined amount, step is performed. The processing is moved to S5.

(Step S4)
When it is determined in step S3 that the remaining amount of power of the power battery 35 is equal to or less than the predetermined amount, in step S4, the CPU sets the direction switching valve 46 to the flow path on the hydraulic motor 34 side and ends the circuit switching process. .

(Step S5)
If it is not determined in step S2 that the load of the actuator driven by the hydraulic oil discharged from the second hydraulic pump 33 is equal to or less than a predetermined value, or the remaining power of the power battery 35 is equal to or less than a predetermined amount in step S3. If not, in step S5, the CPU sets the direction switching valve 46 to the bypass flow path 45 side, and ends the circuit switching process.

  Thus, according to the work vehicle of the present embodiment, power is generated by the power of the first generator 38 that generates power using the power of the engine E and the hydraulic motor 34 that is driven by the hydraulic oil discharged from the second hydraulic pump 33. The second power generator 39, the power generated by the first power generator 38 and the power generated by the second power generator 39 are provided so as to be able to store power, and can be supplied with power when the crane device 20 is driven by the power. And a battery 35. As a result, while the engine E is being driven, the power battery 35 can be charged with the electric power generated by the first generator 38 and the load of the actuator driven by the hydraulic oil discharged from the second hydraulic pump 33 is increased. Since the electric power generated by the second generator 39 can be charged to the power battery 35 when the power is small, the electric power for driving the crane device 20 can be reliably charged to the power battery 35, and the crane device by the electric motor 36 is used. It is possible to prevent power shortage at the time of driving 20.

  Further, when the load of the actuator driven by the hydraulic oil discharged from the second hydraulic pump 33 is less than or equal to a predetermined value, the second generator 39 generates power, and when the crane work load is greater than the predetermined value, the second generator 39 The power generation by is regulated. As a result, the power of the engine E can be used preferentially for the actuator driven by the hydraulic oil discharged from the second hydraulic pump 33, so that it is possible to prevent a reduction in work efficiency.

  Power generation by the second generator 39 is performed when the remaining amount of power in the power battery 35 is less than or equal to a predetermined amount, and power generation by the second generator 39 is restricted when the remaining amount of power in the power battery 35 is greater than a predetermined amount. ing. Accordingly, when the power battery 35 is not required to be charged, the hydraulic motor 34 can be stopped, so that the efficiency during crane work can be improved.

  FIG. 4 shows another embodiment of the present invention. In addition, the same code | symbol is attached | subjected and shown to the component similar to the said embodiment.

  As shown in FIG. 4, in the hydraulic supply device 30 of the mobile crane 1 of the present embodiment, a hydraulic motor 34 and a bypass passage 45 are connected in parallel to the discharge side of the first hydraulic pump 32 of the hydraulic oil circuit 41. The direction switching valve 46 switches the discharge side of the first hydraulic pump 32 to the flow path on the hydraulic motor 34 side or the bypass flow path 45.

  In the mobile crane as the work vehicle configured as described above, when the load of the crane work is small when the crane apparatus 20 is on standby, the first hydraulic pump is driven by the direction switching valve 46 as in the above embodiment. Is switched to the hydraulic motor 34 side to drive the hydraulic motor 34. When the hydraulic motor 34 is driven, power is transmitted to the second generator 39 to start power generation, so that the power battery 35 is charged with the generated power.

  Thus, according to the work vehicle of the present embodiment, power is generated by the power of the first generator 38 that generates power using the power of the engine E and the hydraulic motor 34 that is driven by the hydraulic oil discharged from the first hydraulic pump 32. The second power generator 39, the power generated by the first power generator 38 and the power generated by the second power generator 39 are provided so as to be able to store power, and can be supplied with power when the crane device 20 is driven by the power. And a battery 35. As a result, while the engine E is being driven, the power battery 35 can be charged with the electric power generated by the first generator 38, and when the crane work load is low, such as when the crane apparatus 20 is on standby, the first operation is performed. Since the electric power generated by the two generators 39 can be charged in the power battery 35, the electric power for driving the crane apparatus 20 can be reliably charged in the power battery 35, and the electric power when the crane apparatus 20 is driven by the electric motor 36. Insufficiency can be prevented.

  In the above-described embodiment, the mobile crane 1 is shown as a work vehicle. However, if the work vehicle has a hydraulic circuit having an engine-driven hydraulic pump or a work device that can be driven by electric power, The present invention can also be applied to work vehicles such as excavators.

  In the above-described embodiment, an example in which hydraulic fluid is discharged by an electrically driven hydraulic pump is shown as an example of electric drive of the work device. However, in the case of electric drive, the work device is directly driven by an electric motor. The part may be driven.

  Further, the power battery 35 of the embodiment may be disposed above or below the swivel base 21 of the mobile crane 1. For example, when the drive unit that is electrically driven is only above the swivel base 21, it is desirable to arrange the drive unit above the swivel base 21. When the drive unit that is electrically driven is only below the swivel base 21, It is desirable to arrange on the lower side of the turntable 21.

  DESCRIPTION OF SYMBOLS 1 ... Mobile crane, 20 ... Crane apparatus, 30 ... Hydraulic supply apparatus, 31 ... PTO mechanism, 32 ... 1st hydraulic pump, 33 ... 2nd hydraulic pump, 34 ... Hydraulic motor, 35 ... Power battery, 36 ... Electric motor 37 ... 3rd hydraulic pump, 38 ... 1st generator, 39 ... 2nd generator, 41 ... Hydraulic oil circuit, 46 ... Directional switching valve, 50 ... Controller, 51 ... 1st electric current detection part, 52 ... 2nd Current detection unit, 53 ... overload prevention device, E ... engine.

Claims (3)

A working vehicle comprising: a vehicle that travels by the power of the engine; and a working device that can be driven by hydraulic oil discharged from a hydraulic pump that is driven by the power of the engine, and that can be driven by electric power,
A first generator that generates power by engine power;
A second generator that generates electric power by the power of an actuator driven by hydraulic oil discharged from a hydraulic pump;
A battery for a vehicle that is capable of storing electric power generated by the first generator and that can supply electric power used on the vehicle side;
A power battery provided so as to be able to store electric power generated by the first generator and electric power generated by the second generator, and capable of supplying electric power when the working device is driven by electric power ,
Electric power generated by the first generator is preferentially supplied as electric power for charging a vehicle battery, and surplus electric power is supplied as electric power for charging a power battery . Load detecting means for detecting a load acting on the drive unit of the working device;
Power generation regulation means for generating power by the second generator when the load detected by the load detection means is less than or equal to a predetermined value, and for regulating power generation by the second generator when the detected load is greater than the predetermined value, The work vehicle according to claim 1. A remaining amount detecting means for detecting the remaining amount of power of the power battery;
Power generation regulating means for generating power by the second generator when the remaining amount detected by the remaining amount detecting means is less than or equal to a predetermined amount, and for regulating power generation by the second generator when the detected remaining amount is greater than the predetermined amount The work vehicle according to claim 1 or 2, further comprising:

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