WO2022210608A1 - Asphalt finisher - Google Patents
Asphalt finisher Download PDFInfo
- Publication number
- WO2022210608A1 WO2022210608A1 PCT/JP2022/015201 JP2022015201W WO2022210608A1 WO 2022210608 A1 WO2022210608 A1 WO 2022210608A1 JP 2022015201 W JP2022015201 W JP 2022015201W WO 2022210608 A1 WO2022210608 A1 WO 2022210608A1
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- WIPO (PCT)
- Prior art keywords
- hopper
- screed
- tractor
- cylinder
- driving force
- Prior art date
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- 239000010426 asphalt Substances 0.000 title claims abstract description 72
- 239000000463 material Substances 0.000 claims abstract description 121
- 239000010720 hydraulic oil Substances 0.000 claims description 89
- 239000003921 oil Substances 0.000 claims description 50
- 230000008859 change Effects 0.000 claims description 5
- 230000007480 spreading Effects 0.000 claims description 5
- 238000010276 construction Methods 0.000 abstract description 12
- 238000005516 engineering process Methods 0.000 abstract description 2
- 239000012530 fluid Substances 0.000 description 34
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- 238000010586 diagram Methods 0.000 description 8
- 230000006870 function Effects 0.000 description 8
- 238000005056 compaction Methods 0.000 description 7
- 101100340248 Arabidopsis thaliana SCRM gene Proteins 0.000 description 5
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- 239000013256 coordination polymer Substances 0.000 description 4
- 102100039028 Protein SPO16 homolog Human genes 0.000 description 3
- 101150108548 SPO16 gene Proteins 0.000 description 3
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- 230000009471 action Effects 0.000 description 2
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- 238000003384 imaging method Methods 0.000 description 2
- 230000002411 adverse Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000007667 floating Methods 0.000 description 1
- 230000002706 hydrostatic effect Effects 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
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Classifications
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- E—FIXED CONSTRUCTIONS
- E01—CONSTRUCTION OF ROADS, RAILWAYS, OR BRIDGES
- E01C—CONSTRUCTION OF, OR SURFACES FOR, ROADS, SPORTS GROUNDS, OR THE LIKE; MACHINES OR AUXILIARY TOOLS FOR CONSTRUCTION OR REPAIR
- E01C19/00—Machines, tools or auxiliary devices for preparing or distributing paving materials, for working the placed materials, or for forming, consolidating, or finishing the paving
- E01C19/48—Machines, tools or auxiliary devices for preparing or distributing paving materials, for working the placed materials, or for forming, consolidating, or finishing the paving for laying-down the materials and consolidating them, or finishing the surface, e.g. slip forms therefor, forming kerbs or gutters in a continuous operation in situ
Definitions
- This disclosure relates to an asphalt finisher.
- An asphalt finisher comprising a tractor, a hopper, a conveyor that conveys the paving material in the hopper to the rear side of the tractor, a screw that spreads the paving material conveyed by the conveyor, and a screed that spreads the paving material evenly behind the screw.
- Sha is known (see Patent Document 1).
- the asphalt finisher constructs the asphalt pavement while receiving pavement material from the dump truck bed adjacent in front to the hopper.
- the amount of pavement material in the hopper is relatively large at the start of loading from the dump truck bed, but gradually decreases as construction progresses. Therefore, as the amount of pavement material in the hopper placed in front of the tractor decreases, the load on the front wheels of the tractor decreases, and as a result, the frictional force between the front wheels and the ground (roadbed) becomes relatively As it becomes smaller, the driving force of the front wheels may become larger than the frictional force. Therefore, when the front wheels slip, the roadbed may be dug and the roadbed may be damaged.
- the purpose is to provide a technology that can suppress damage to the roadbed during construction of asphalt pavement.
- a tractor a hopper located in front of the tractor for receiving paving material; a conveyor for transporting the paving material in the hopper to the rear of the tractor; a screw for spreading the pavement material conveyed by the conveyor on the rear side of the tractor; a screed for evenly spreading the pavement material spread by the screw behind the screw; a control unit that controls the driving force of the front wheels of the tractor based on the weight of the pavement material in the hopper; An asphalt finisher is provided.
- FIG. 1 is a schematic diagram of an asphalt finisher;
- FIG. 1 is a schematic diagram of an asphalt finisher;
- FIG. It is a functional block diagram showing an example of a configuration of a controller.
- 1 is a hydraulic circuit diagram showing an example of the configuration of a hydraulic system of an asphalt finisher;
- FIG. It is a figure explaining an example of the control method of the driving force of a front wheel.
- It is a front view which shows the state of the pavement material inside a hopper.
- It is a front view which shows the state of the pavement material inside a hopper.
- It is a front view which shows the state of the pavement material inside a hopper.
- It is a front view which shows the state of the pavement material inside a hopper.
- It is a front view which shows the state of the pavement material inside a hopper.
- FIG. 1A and 1B are diagrams showing an example of an asphalt finisher 100 according to this embodiment. Specifically, FIG. 1A is a left side view of the asphalt finisher 100, and FIG. 1B is a top view of the asphalt finisher 100. FIG.
- the asphalt finisher 100 is arranged such that its vehicle length direction, vehicle width direction, and vehicle height direction correspond to the X-axis direction, Y-axis direction, and Z-axis direction, respectively.
- the front side in the vehicle length direction that is, the front direction of the asphalt finisher 100 corresponds to the positive direction (+X side) of the X axis
- the rear side in the vehicle length direction that is, the rear direction of the asphalt finisher 100 corresponds to the X axis. It corresponds to the negative direction (-X side).
- the left side of the vehicle width direction that is, the left direction of the asphalt finisher 100 corresponds to the Y-axis positive direction (+Y side)
- the right side of the vehicle width direction that is, the right direction of the asphalt finisher 100 corresponds to the Y-axis negative direction (- Y side)
- the upper side in the vehicle height direction that is, the upward direction of the asphalt finisher 100 corresponds to the Z-axis positive direction (+Z side)
- the lower side in the vehicle height direction that is, the downward direction of the asphalt finisher 100 corresponds to the Z-axis negative direction ( -Z side).
- the asphalt finisher 100 includes a tractor 1, a hopper 2, a conveyor CV, a screw SC, and a screed 3.
- the tractor 1 corresponds to the main body of the asphalt finisher 100 and causes the asphalt finisher 100 to travel.
- the tractor 1 includes rear wheels 5 and front wheels 6, rotates the rear wheels 5 using a rear wheel drive motor 20 (see FIG. 3), and rotates the front wheels using a front wheel drive motor 22 (see FIG. 3). By rotating 6, the asphalt finisher 100 is run.
- the tractor 1 may have crawlers instead of the wheels (rear wheels 5 and front wheels 6).
- a driver's seat is provided on the top of the tractor 1. An operator can operate the asphalt finisher from the driver's seat above the tractor 1 .
- the tractor 1 is equipped with a controller 50, for example.
- the controller 50 controls the asphalt finisher 100.
- the functions of the controller 50 may be realized by arbitrary hardware or a combination of arbitrary hardware and software.
- the controller 50 includes, for example, a CPU (Central Processing Unit), a memory device such as RAM (Random Access Memory), a non-volatile auxiliary storage device such as ROM (Read Only Memory), and an interface device for input/output with the outside. It consists mainly of a computer including
- the controller 50 implements various functions by, for example, loading a program installed in the auxiliary storage device into the memory device and causing the CPU to execute the program.
- the controller 50 may control the discharge amount of various hydraulic pumps described later that supply hydraulic fluid for driving the hydraulic actuators.
- Hydraulic actuators include various hydraulic cylinders and hydraulic motors, as described later.
- controller 50 may control the flow of hydraulic fluid between the hydraulic actuator and the hydraulic pump.
- Hopper 2 receives pavement material supplied from the dump truck bed.
- the pavement material is, for example, an asphalt mixture or the like.
- the hopper 2 is provided in the front part of the tractor 1.
- the hopper 2 includes left and right hopper wings 2W (left hopper wing 2WL and right hopper wing 2WR) (see FIG. 5). configured to be openable and closable.
- the asphalt finisher 100 normally opens the hopper 2 to receive pavement material from the dump truck bed. Further, the asphalt finisher 100 continues to travel while pushing the dump truck forward via the push rollers 2b even when receiving pavement material from the bed of the dump truck. An operator of the asphalt finisher 100 closes the hopper 2 when the pavement material in the hopper 2 is reduced, and collects the pavement material near the inner wall of the hopper 2 in the center of the hopper 2 .
- the asphalt finisher 100 can convey the pavement material to the rear side of the tractor 1 by the conveyor CV at the bottom of the central portion of the hopper 2. state can be maintained.
- the pavement material conveyed to the rear of the tractor 1 is spread in the direction of the tractor 1 and in front of the screed 3 in the vehicle width direction by the screw SC.
- FIG. 1 shows the asphalt finisher 100 when the hopper 2 is fully open.
- the tractor 1 is equipped with a space recognition device CM.
- the space recognition device CM is attached to the front upper surface of the tractor 1, specifically the front end of the driver's seat on the top of the tractor 1, and acquires data for monitoring the condition of the pavement material in the hopper 2.
- Space recognition device CM may contain the imaging device which can image the inside of the hopper 2, for example. Imaging devices may include, for example, monocular cameras, stereo cameras, three-dimensional cameras, depth cameras, and the like.
- the space recognition device CM may also include a distance sensor such as LIDAR (Light Detecting and Ranging), millimeter wave radar, and ultrasonic sensor.
- LIDAR Light Detecting and Ranging
- the output data of the spatial recognition device CM is taken into the controller 50 . Thereby, the controller 50 can recognize the amount of pavement material in the hopper 2 based on the output data of the space recognition device CM.
- the conveyor CV conveys the paving material in the center of the hopper 2 to the rear of the tractor 1.
- the conveyor CV is driven by a hydraulic motor (conveyor motor 21C, described later) that rotates by receiving hydraulic fluid supplied from a hydraulic pump (conveyor/screw pump 14S, described later).
- the conveyor CV is configured to be able to transport the pavement material in the hopper 2 to the rear side of the tractor 1 via the transport passage CP provided in the tractor 1 .
- the transport passage CP is a substantially rectangular parallelepiped space formed inside the tractor 1 and has a substantially rectangular entrance OP that opens into the hopper 2 on the front surface of the tractor 1 .
- the conveyor CV includes, for example, two conveyors arranged on the left and right sides of the center of the asphalt finisher 100 (tractor 1) in the vehicle width direction (Y-axis direction).
- the left conveyor of the two conveyors is configured to convey pavement material towards the left main screw SCLM described below, and the right conveyor is adapted to convey pavement material towards the right main screw SCRM described below. Configured.
- the screw SC spreads the paving material conveyed to the ground on the rear side of the tractor 1 by the conveyor CV.
- the screw SC is driven by a hydraulic motor (screw motor 21S, which will be described later) that rotates by receiving supply of hydraulic oil from a hydraulic pump (conveyor/screw pump 14S, which will be described later).
- the screw SC includes a left main screw SCLM, a right main screw SCRM, a left extension screw SCLE and a right extension screw SCRE.
- the left main screw SCLM and the right main screw SCRM are arranged so as to fit within the width of the tractor 1 in the vehicle width direction.
- the left extension screw SCLE is connected to the left end of the left main screw SCLM and arranged to protrude leftward from the left end of the tractor 1 in the vehicle width direction (Y-axis direction).
- the right extension screw SCRE is connected to the right end of the right main screw SCRM and arranged to protrude rightward from the right end of the tractor 1 in the vehicle width direction.
- the screed 3 spreads the pavement material evenly behind the screw SC.
- the screed 3 includes a main screed 30 and an extension screed 31 .
- the main screed 30 includes, for example, a left main screed and a right main screed arranged on the left and right sides with respect to the center of the asphalt finisher 100 (tractor 1) in the vehicle width direction.
- the telescopic screed 31 includes a left telescopic screed 31L and a right telescopic screed 31R.
- the main screed 30, the left telescopic screed 31L, and the right telescopic screed 31R are staggered forward and backward so as not to overlap in the vehicle length direction (X-axis direction).
- the left telescopic screed 31L is arranged on the rear side of the main screed 30, and the right telescopic screed 31R is arranged on the rear side of the left telescopic screed 31L.
- the telescopic screed 31 is configured to be telescopic in the vehicle width direction by the screed telescopic cylinder 27 .
- the screed telescopic cylinder 27 is supported by a support portion fixed to the rear surface of the housing of the main screed 30, and is configured to be able to telescopically extend and retract the telescopic screed 31 in the vehicle width direction.
- the screed telescoping cylinders 27 include a left screed telescoping cylinder 27L and a right screed telescoping cylinder 27R.
- the left screed telescopic cylinder 27L can extend and retract the left telescopic screed 31L with respect to the main screed 30 to the left in the vehicle width direction.
- the right screed telescopic cylinder 27R can extend and retract the right telescopic screed 31R to the right in the vehicle width direction with respect to the main screed 30 .
- the screed 3 is a floating screed towed by the tractor 1 and is connected to the tractor 1 via leveling arms 3A.
- the screed 3 is moved up and down together with the leveling arm 3A by extension and contraction of the screed lift cylinder 25. As shown in FIG.
- the leveling arm 3A is configured so that the screed 3 can be connected to the tractor 1. Specifically, the leveling arm 3A has one end connected to the screed 3 and the other end rotatably connected to the tractor 1 .
- the leveling arm 3A includes a left leveling arm 3AL and a right leveling arm 3AR.
- the leveling cylinder 23 is configured so that the front end portion of the leveling arm 3A can be moved up and down in order to adjust the thickness of pavement material (pavement thickness).
- the leveling cylinder 23 may have a cylinder portion connected to the tractor 1 and a rod portion connected to the front end portion of the leveling arm 3A.
- the front end portion of the leveling arm 3A is slidably supported by the tractor 1.
- the controller 50 causes hydraulic oil discharged from a hydraulic pump (cylinder pump 14M, which will be described later) to flow into the rod-side oil chamber of the leveling cylinder 23, contract the leveling cylinder 23, and extend the leveling arm 3A. Raise the front end.
- the controller 50 causes the hydraulic oil in the rod-side oil chamber of the leveling cylinder 23 to flow out, extends the leveling cylinder 23, and lowers the front end portion of the leveling arm 3A.
- the screed lift cylinder 25 lifts the screed 3 from the construction state (hereinafter, “construction state”) to a state relatively separated from the ground (hereinafter, “lift-up state”), or lifts the screed 3 from the lift-up state. It is used to return to the construction state.
- construction state construction state
- lift-up state a state relatively separated from the ground
- the screed 3 is maintained in a lifted state relatively away from the ground (roadbed) in situations other than the construction work of the asphalt pavement, and the screed 3 and the roadbed are damaged by the contact between the screed 3 and the ground. such situations can be prevented.
- the screed lift cylinder 25 may have a cylinder portion connected to the tractor 1 and a rod portion connected to the rear end portion of the leveling arm 3A.
- the controller 50 When lifting the screed 3 , the controller 50 causes hydraulic oil discharged by a hydraulic pump (cylinder pump 14 ⁇ /b>M described later) to flow into the rod-side oil chamber of the screed lift cylinder 25 . As a result, the screed lift cylinder 25 is contracted, the rear end portion of the leveling arm 3A is lifted, and the screed 3 is lifted. On the other hand, when the lifted screed 3 is lowered, the controller 50 allows the hydraulic oil in the rod-side oil chamber of the screed lift cylinder 25 to flow out. As a result, the screed lift cylinder 25 is extended by the weight of the screed 3, the rear end portion of the leveling arm 3A is lowered, and the screed 3 is lowered.
- the function of lifting the screed 3 and lowering the lifted screed 3 using the screed lift cylinder 25 may be referred to as "screed lift function".
- the asphalt finisher 100 also includes a side plate 40, an elastic mold board, a screed step 42, and a retaining plate 43.
- the side plate 40 is attached to the outer end of the telescopic screed 31 in the vehicle width direction.
- the side plates 40 include a left side plate 40L and a right side plate 40R. Specifically, the left side plate 40L is attached to the outer end (left end) of the left telescopic screed 31L in the vehicle width direction (Y-axis direction), and the right side plate 40R is attached to the right telescopic screed 31R in the vehicle width direction. is attached to the outer end (right end) of the
- the telescopic mold board 41 is a member for adjusting the amount of pavement material that remains in front of the telescopic screed 31 among the pavement materials spread by the screws SC.
- the telescopic mold board 41 is configured to be telescopic in the vehicle width direction together with the telescopic screed 31 .
- a side plate 40 is connected to the outer end of the expandable mold board 41 in the vehicle width direction (Y-axis direction).
- the telescoping moldboard 41 is a plate-like member extending in the vehicle width direction, and includes a left telescoping moldboard 41L and a right telescoping moldboard 41R.
- a left side plate 40L is attached to the outer end (left end) of the left telescopic moldboard 41L in the vehicle width direction
- a right side plate 40R is attached to the outer end (right end) of the right telescopic moldboard 41R.
- the telescopic mold board 41 is configured to be adjustable in height in the Z-axis direction independently of the telescopic screed 31 and the side plates 40 .
- the asphalt finisher 100 moves the expandable moldboard 41 up and down to adjust the size of the gap between the lower end of the expandable moldboard 41 and the roadbed. You can adjust the amount of Therefore, the asphalt finisher 100 can adjust the amount (height) of pavement material remaining behind the telescopic moldboard 41 and in front of the telescopic screed 31 by moving the telescopic moldboard 41 up and down. can.
- the asphalt finisher 100 can also adjust the amount of pavement material taken in under the telescopic screed 31 .
- the screed step 42 is a member used as a scaffolding when the worker works behind the screed 3.
- the screed steps 42 include a left screed step 42L, a central screed step 42C, and a right screed step 42R.
- the retaining plate 43 is a plate-like member for preventing the pavement material sent out in the vehicle width direction by the screw SC from scattering in front of the screw SC.
- the asphalt finisher 100 can appropriately send out the pavement material in the vehicle width direction using the screw SC by the action of the retaining plate 43 .
- the retaining plate 43 includes a left retaining plate 43L and a right retaining plate 43R.
- FIG. 2 is a functional block diagram showing an example of the configuration of the controller 50. As shown in FIG.
- the controller 50 includes a pavement material weight acquisition section 50A and a front wheel driving force control section 50B.
- the functions of the pavement material weight acquisition unit 50A and the front wheel driving force control unit 50B are realized by, for example, loading a predetermined program installed in the auxiliary storage device into the memory device and executing it on the CPU.
- the pavement material weight acquisition unit 50A acquires information on the weight of the pavement material inside the hopper 2 . Specifically, while the asphalt finisher 100 is in operation, the pavement material weight acquisition unit 50A may repeat the process of acquiring information about the weight of the pavement material inside the hopper 2 at each predetermined control cycle.
- the pavement material weight acquisition unit 50A estimates the amount (volume) of the pavement material inside the hopper 2 based on the output data taken in from the space recognition device CM. At this time, the pavement material weight acquisition unit 50A may estimate the amount (volume) of the pavement material inside the hopper 2 in consideration of the open/closed state of the hopper 2, that is, the expansion/contraction state of the hopper cylinder 24. This is because the shape of the paving material storage portion inside the hopper 2 changes depending on the open/closed state of the hopper 2 . Then, the pavement material weight acquisition unit 50A estimates the weight of the pavement material inside the hopper 2 based on the estimated volume of the pavement material inside the hopper 2, the density of the pavement material (mass per unit volume), etc. ( calculation).
- the pavement material weight acquisition unit 50A may estimate (calculate) the weight of the pavement material inside the hopper 2 based on the output of a load cell or strain gauge installed in the hopper 2, for example.
- the front wheel driving force control unit 50B (an example of the control unit) performs control to adjust the driving force of the front wheels 6 based on the information regarding the weight of the pavement material inside the hopper 2 acquired by the pavement material weight acquisition unit 50A. . Specifically, the front wheel driving force control unit 50B repeats the processing related to the control of adjusting the driving force of the front wheels 6 at each predetermined control cycle while synchronizing with the processing of the pavement material weight acquisition unit 50A.
- the front wheel driving force control unit 50B adjusts the driving force of the front wheels 6 to be relatively large when the weight of the pavement material inside the hopper 2 is relatively large.
- the front wheel driving force control section 50B adjusts the driving force of the front wheels 6 to be relatively small.
- the controller 50 can adjust the driving force of the front wheels 6 according to the weight of the pavement material inside the hopper 2 , that is, the magnitude of the load acting on the front wheels 6 . Therefore, it is possible to prevent the driving force of the front wheels 6 from exceeding the frictional force between the front wheels 6 and the roadbed, thereby preventing the front wheels 6 from slipping (wheelspin).
- the front wheel driving force control unit 50B sets a target value that is changed in accordance with a change in the weight of the pavement material acquired by the pavement material weight acquisition unit 50A while the asphalt finisher 100 (tractor 1) is running.
- the driving force of the front wheels 6 is controlled so as to maintain the Thereby, the controller 50 can be realized corresponding to the weight of the pavement material inside the hopper 2 .
- the front wheel drive force control unit 50B outputs a control command to a relief valve RV, which will be described later, and adjusts the pressure of the hydraulic oil supplied to the front wheel traveling motor 22, which drives the front wheels 6, which will be described later. may be controlled (adjusted). That is, the front wheel driving force control section 50B may adjust the driving force of the front wheels 6 with the relief valve RV as the direct control target.
- the front-wheel driving force control unit 50B controls a front-wheel drive pump 14F (specifically, a regulator that adjusts the tilt angle of the swash plate of the front-wheel drive pump 14F), which will be described later.
- a control command may be output. That is, the front wheel driving force control unit 50B may adjust the driving force of the front wheels 6 by directly controlling the front wheel driving pump 14F (regulator) in addition to the relief valve RV.
- the front-wheel driving force control unit 50B adjusts the angle of the swash plate of the front-wheel drive pump 14F (hereinafter referred to as the "tilt angle"), and adjusts the pressure of the hydraulic oil supplied to the front-wheel drive motor 22. be able to.
- the front wheel driving force control unit 50B determines a target value of the driving force of the front wheels 6 according to, for example, the weight of the pavement material inside the hopper 2, and directly controls the object ( The control amount of the relief valve RV and the front wheel running pump 14F) may be controlled. Further, the front wheel driving force control unit 50B, for example, controls the weight of the pavement material and the control amount to be directly controlled, which are predetermined so as to achieve the target value of the driving force of the front wheels 6 in accordance with the weight of the pavement material.
- the control amount of the direct controlled object may be controlled in accordance with a control law (see FIG. 4 described later) that expresses the relationship of .
- the controller 50 can control the driving force of the front wheels 6 so as to maintain the target value of the driving force of the front wheels 6 which is changed according to the change in the weight of the pavement material inside the hopper 2 . Therefore, the controller 50 can appropriately control the driving force of the front wheels 6 according to changes in the weight of the pavement material inside the hopper 2 .
- FIG. 3 is a hydraulic circuit diagram showing an example of the configuration of the hydraulic system of the asphalt finisher 100. As shown in FIG.
- the hydraulic system includes a hydraulic source 14, a rear wheel drive F1, a conveyor and screw drive F2, a front wheel drive F3, a steering and compaction device drive F4, a leveling station F5 and a hopper drive F6. , a screed lift portion F7 and a screed telescoping portion F8.
- the hydraulic pressure source 14 sucks up hydraulic oil from the hydraulic oil tank T and supplies the hydraulic oil to various drive units.
- the hydraulic source 14 includes an engine 14E, a rear-wheel drive pump 14R, a charge pump 14C, a cylinder pump 14M, a conveyor/screw pump 14S, and a front-wheel drive pump 14F.
- the engine 14E is a driving source for driving the rear wheel running pump 14R, the charge pump 14C, the cylinder pump 14M, the conveyor/screw pump 14S, and the front wheel running pump 14F.
- the rear-wheel drive pump 14R is a variable displacement hydraulic pump that supplies hydraulic oil for driving to the rear-wheel drive portion F1.
- the rear wheel running pump 14R may be a swash plate type variable capacity bi-directional hydraulic pump used in a closed circuit.
- the charge pump 14C is a fixed displacement hydraulic pump that supplies hydraulic oil for control to the rear wheel drive unit F1.
- the cylinder pump 14M is a variable displacement hydraulic pump capable of supplying hydraulic oil to each of the steering/compaction device driving portion F4, the leveling portion F5, the hopper driving portion F6, the screed lift portion F7, and the screed extension/contraction portion F8. .
- the cylinder pump 14M is a swash plate type variable displacement hydraulic pump, and its discharge amount is controlled so that the discharge pressure is constant at a predetermined pressure.
- the conveyor/screw pump 14S is a variable displacement hydraulic pump that supplies hydraulic oil to the conveyor/screw driving portion F2.
- the conveyor/screw pump 14S may be a swash plate type variable displacement hydraulic pump.
- the front-wheel drive pump 14F (an example of a hydraulic pump) is a variable displacement hydraulic pump that supplies hydraulic oil to the front-wheel drive unit F3.
- the front wheel running pump 14F is a swash plate type variable displacement hydraulic pump.
- the rear wheel drive unit F1 is configured to be able to drive the rear wheels 5 using hydraulic fluid supplied from the hydraulic source 14.
- the rear wheel drive unit F1 includes a left rear wheel drive motor 20L, a right rear wheel drive motor 20R, check valves 20La and 20Ra, relief valves 20Lb and 20Rb, and a reduction gear switching valve V0.
- the left rear wheel drive motor 20L and the right rear wheel drive motor 20R drive the left and right rear wheels, respectively.
- the left rear wheel drive motor 20L and the right rear wheel drive motor 20R may be continuously variable speed hydraulic motors, and together with the rear wheel drive pump 14R, a closed circuit, that is, HST (Hydro-Static Motor). transmission) circuit.
- HST Hydro-Static Motor
- the check valve 20La is connected to the first port ((1) in the figure) of the rear wheel drive pump 14R and the second port ((1) in the figure) of each of the left rear wheel drive motor 20L and the right rear wheel drive motor 20R. 2)
- the pressure of hydraulic fluid in the conduit C1 connecting ) is maintained at a predetermined pressure or higher.
- the check valve 20La allows the hydraulic fluid discharged from the charge pump 14C to flow into the pipeline C1 when the pressure of the hydraulic fluid in the pipeline C1 is lower than the discharge pressure of the charge pump 14C.
- the check valve 20Ra is connected to the second port ((2) in the figure) of the rear wheel drive pump 14R and the first ports ((2) in the figure) of the left rear wheel drive motor 20L and the right rear wheel drive motor 20R.
- the pressure of hydraulic oil in the pipe line C2 connecting (1)) is maintained at a predetermined pressure or higher.
- the check valve 20Ra allows the hydraulic fluid discharged from the charge pump 14C to flow into the pipeline C2 when the pressure of the hydraulic fluid in the pipeline C2 is lower than the discharge pressure of the charge pump 14C.
- the relief valve 20Lb maintains the pressure of hydraulic fluid in the conduit C1 below a predetermined relief pressure. Specifically, the relief valve 20Lb causes the hydraulic fluid in the pipeline C1 to flow out to the outside of the closed circuit (for example, the hydraulic fluid tank T) when the pressure of the hydraulic fluid in the pipeline C1 exceeds the relief pressure. . Similarly, the relief valve 20Rb maintains the pressure of hydraulic fluid in the conduit C2 below a predetermined relief pressure. Specifically, the relief valve 20Rb causes the hydraulic fluid in the pipeline C2 to flow out to the outside of the closed circuit (for example, the hydraulic fluid tank T) when the pressure of the hydraulic fluid in the pipeline C2 exceeds the relief pressure. .
- the speed reducer switching valve V0 switches the speed reduction ratios of the left rear wheel drive motor 20L and the right rear wheel drive motor 20R. Specifically, the speed reducer switching valve V0 utilizes hydraulic oil discharged from the charge pump 14C in accordance with a control command from the controller 50 to switch the left rear wheel drive motor 20L and the right rear wheel drive motor 20R respectively. switch the reduction ratio of
- the conveyor/screw drive unit F2 is configured to be able to drive the conveyor CV and the screw SC using hydraulic oil supplied from the hydraulic source 14.
- the conveyor/screw drive unit F2 includes a conveyor motor 21C, a screw motor 21S, a conveyor control valve V1C, and a screw control valve V1S.
- Both the conveyor motor 21C and the screw motor 21S are variable displacement hydraulic motors that form an open circuit.
- the conveyor motor 21C includes a left conveyor motor 21CL and a right conveyor motor 21CR.
- the screw motor 21S includes a left screw motor 21SL and a right screw motor 21SR.
- the conveyor control valve V1C includes a left conveyor control valve V1CL and a right conveyor control valve V1CR.
- the screw control valve V1S includes a left screw control valve V1SL and a right screw control valve V1SR.
- the left conveyor control valve V1CL operates in accordance with a control command from the controller 50 to allow the hydraulic oil discharged by the conveyor/screw pump 14S to flow into the suction port of the left conveyor motor 21CL and Hydraulic oil flowing out from the discharge port of 21CL is discharged to the hydraulic oil tank T.
- the right conveyor control valve V1CR operates in accordance with a control command from the controller 50 to allow the hydraulic oil discharged by the conveyor/screw pump 14S to flow into the suction port of the right conveyor motor 21CR, Hydraulic oil flowing out from the discharge port of 21CR is discharged to the hydraulic oil tank T.
- the left screw control valve V1SL operates in accordance with a control command from the controller 50 to allow the hydraulic oil discharged by the conveyor/screw pump 14S to flow into the suction port of the left screw motor 21SL and The hydraulic fluid flowing out from the discharge port of the screw motor 21SL is discharged to the hydraulic fluid tank T.
- the right screw control valve V1SR operates in response to a control command from the controller 50 to allow the hydraulic fluid discharged by the conveyor/screw pump 14S to flow into the suction port of the right screw motor 21SR and to control the right screw motor 21SR.
- 21SR discharges the hydraulic oil flowing out from the discharge port to the hydraulic oil tank T. Hydraulic oil flowing out from the discharge port of each of the left conveyor motor 21CL, the right conveyor motor 21CR, the left screw motor 21SL, and the right screw motor 21SR is discharged to the hydraulic oil tank T through the oil cooler OC. .
- the front wheel drive unit F3 is configured to be able to drive the front wheels 6 using hydraulic oil supplied from the hydraulic source 14.
- the front-wheel drive unit F3 includes a front-wheel drive motor 22, a front-wheel drive valve V2, and a relief valve RV.
- the front wheel traveling motor 22 (an example of a hydraulic motor) is a fixed displacement hydraulic motor that forms an open circuit.
- the front wheel driving motor 22 includes a left front wheel driving motor 22L that drives the left front wheel 6L (see FIG. 5) of the front wheels 6, and a right front wheel driving motor 22L that drives the right front wheel 6R (see FIG. 5) of the front wheels 6. includes a motor 22R for
- the front-wheel drive valve V2 operates according to a control command from the controller 50, and causes hydraulic oil discharged from the front-wheel drive pump 14F to flow into the suction port of the front-wheel drive motor 22.
- the front-wheel drive pump 14F supplies hydraulic fluid to the left front-wheel drive motor 22L and the right front-wheel drive motor 22R in parallel via the front-wheel drive valve V2.
- the relief valve RV is provided in the oil passage between the front wheel travel pump 14F and the front wheel travel valve V2.
- the relief valve RV is, for example, an electromagnetic relief valve.
- the relief valve RV discharges the hydraulic oil in the oil passage to the hydraulic oil tank T when the pressure of the hydraulic oil in the oil passage between the front wheel traveling pump 14F and the front wheel traveling motor 22 reaches a predetermined relief pressure.
- the pressure of the hydraulic fluid supplied to the front-wheel drive motor 22 can be limited to a predetermined relief pressure or less.
- the relief pressure of the relief valve RV is variable.
- the controller 50 transmits a control command designating the setting content (set value) of the relief pressure to the relief valve RV.
- the relief valve RV sets (changes) the relief pressure according to the control command input from the controller 50 .
- the relief valve RV can maintain the pressure of the working oil in the oil passages between the front-wheel drive pump 14F and the front-wheel drive motor 22 to be equal to or lower than the set relief pressure. Therefore, the controller 50 (the front wheel driving force control section 50B) adjusts the pressure of the hydraulic oil supplied to the front wheel traveling motor 22 by varying the relief pressure of the relief valve RV. power can be adjusted.
- the steering/compaction device drive unit F4 is configured to be able to drive the steering device and the compaction device (both not shown) using hydraulic oil supplied from the hydraulic source 14 .
- the steering device is a hydraulic device for steering the front wheels 6.
- the steering system changes the steering angle of the front wheels 6 using hydraulic oil discharged from the cylinder pump 14M, for example, according to the operator's operation of the steering wheel.
- the compaction device is a hydraulic device for compacting the paving material.
- the compaction device includes a tamper and a vibrator, and operates the tamper and vibrator using hydraulic oil discharged from the cylinder pump 14M.
- the leveling part F5 is configured so that the pavement thickness can be adjusted using hydraulic oil supplied from the hydraulic pressure source 14.
- the leveling part F5 includes a leveling cylinder 23, a leveling control valve 33, and a pilot check valve 33P.
- the leveling cylinder 23 moves the leveling arm 3A up and down to adjust the pavement thickness as described above. Specifically, the leveling cylinder 23 is configured to contract when increasing the pavement thickness and to expand when decreasing the pavement thickness.
- the leveling cylinders 23 include a left leveling cylinder 23L and a right leveling cylinder 23R.
- the leveling control valve 33 operates according to a control signal from the controller 50 to control the flow rate and flow direction of hydraulic oil supplied to the leveling cylinder 23 .
- the leveling control valve 33 includes a left leveling control valve 33L and a right leveling control valve 33R.
- the left leveling control valve 33L causes the hydraulic oil discharged from the cylinder pump 14M to flow into the rod-side oil chamber of the left leveling cylinder 23L and to flow from the head-side oil chamber of the left leveling cylinder 23L.
- the hydraulic oil that flows out is discharged to the hydraulic oil tank T. In this case, the left leveling cylinder 23L contracts and the left leveling arm 3AL rises.
- the left leveling control valve 33L causes the hydraulic oil discharged by the cylinder pump 14M to flow into the head side oil chamber of the left leveling cylinder 23L, and the rod side oil of the left leveling cylinder 23L. Hydraulic oil flowing out of the chamber is discharged to the hydraulic oil tank T. In this case, the left leveling cylinder 23L extends and the left leveling arm 3AL descends. The same applies to the right leveling control valve 33R that extends the right leveling cylinder 23R.
- the pilot check valve 33P is configured to prevent the leveling cylinder 23 from moving due to an external force.
- the pilot check valve 33P includes pilot check valves 33PaL, 33PbL, 33PaR, and 33PbR.
- the pilot check valve 33PaL operates only when the left leveling control valve 33L operates in response to an operator's operation and the hydraulic oil discharged from the cylinder pump 14M flows into the head-side oil chamber of the left leveling cylinder 23L. Hydraulic oil in the rod-side oil chamber of the left leveling cylinder 23L is allowed to flow toward the hydraulic oil tank T.
- the pilot check valve 33PaL prohibits the hydraulic oil in the rod-side oil chamber of the left leveling cylinder 23L from flowing toward the hydraulic oil tank T in other cases. The same applies to the pilot check valves 33PbL, 33PaR, and 33PbR.
- the hopper driving part F6 is configured to be able to open and close the hopper 2 using hydraulic oil supplied from the hydraulic pressure source 14.
- the hopper driving part F6 includes a hopper cylinder 24, a hopper control valve 34, and a pilot check valve 34P.
- the hopper cylinder 24 opens and closes the hopper 2.
- the hopper cylinder 24 contracts when the hopper 2 is opened and extends when the hopper 2 is closed.
- the hopper cylinders 24 include a left hopper cylinder 24L and a right hopper cylinder 24R.
- the hopper control valve 34 operates according to a control signal from the controller 50 to control the flow rate and flow direction of hydraulic oil supplied to the hopper cylinder 24 .
- the hopper control valves 34 include a left hopper control valve 34L and a right hopper control valve 34R.
- the left hopper control valve 34L causes the hydraulic oil discharged from the cylinder pump 14M to flow into the rod-side oil chamber of the left hopper cylinder 24L and to flow from the head-side oil chamber of the left hopper cylinder 24L.
- the hydraulic oil that flows out is discharged to the hydraulic oil tank T. In this case, the left hopper cylinder 24L contracts.
- the right hopper control valve 34R causes the hydraulic fluid discharged from the cylinder pump 14M to flow into the rod side oil chamber of the right hopper cylinder 24R, and the hydraulic fluid flowing out from the head side oil chamber of the right hopper cylinder 24R. Drain to hydraulic oil tank T. In this case, the right hopper cylinder 24R contracts.
- the left hopper control valve 34L causes the hydraulic oil discharged by the cylinder pump 14M to flow into the head side oil chamber of the left hopper cylinder 24L, and the rod side oil of the left hopper cylinder 24L. Hydraulic oil flowing out of the chamber is discharged to the hydraulic oil tank T. In this case, the left hopper cylinder 24L extends.
- the right hopper control valve 34R allows the hydraulic fluid discharged from the cylinder pump 14M to flow into the head-side oil chamber of the right hopper cylinder 24R, and the hydraulic fluid flowing out from the rod-side oil chamber of the right hopper cylinder 24R. Drain to hydraulic oil tank T. In this case, the right hopper cylinder 24R extends.
- the pilot check valve 34P is configured to prevent the hopper 2 from opening due to contraction of the hopper cylinder 24 due to the weight of the hopper 2 or the weight of the hopper 2 and the pavement material in the hopper 2.
- the pilot check valve 34P includes a pilot check valve 34PL and a pilot check valve 34PR.
- the pilot check valve 34PL operates only when the left hopper control valve 34L operates according to the operator's operation and the hydraulic oil discharged by the cylinder pump 14M flows into the rod side oil chamber of the left hopper cylinder 24L. Hydraulic oil in the head-side oil chamber of the left hopper cylinder 24L is allowed to flow toward the hydraulic oil tank T.
- the pilot check valve 34PL prohibits the hydraulic oil in the head-side oil chamber of the left hopper cylinder 24L from flowing toward the hydraulic oil tank T in other cases. The same applies to the pilot check valve 34PR.
- the screed lift portion F7 is configured to be able to lift the screed 3 and lower the lifted screed using hydraulic oil supplied from the hydraulic pressure source 14.
- the screed lift portion F7 includes a screed lift cylinder 25, a screed lift control valve 35, a switching valve 35a, a relief valve 35b, and a switching valve 35c.
- the screed lift cylinder 25 lifts the screed 3 and lowers the lifted screed 3 as described above. Specifically, the screed lift cylinder 25 contracts when the screed 3 is lifted, and expands when the screed 3 is lowered.
- the screed lift cylinders 25 include a left screed lift cylinder 25L and a right screed lift cylinder 25R.
- the screed lift control valve 35 operates according to a control signal from the controller 50 to control the flow rate and flow direction of hydraulic oil supplied to the screed lift cylinder 25 .
- the screed lift control valve 35 causes the hydraulic oil discharged by the cylinder pump 14M to flow into the rod side oil chamber of the screed lift cylinder 25 .
- the switching valve 35 a is switched to the first position including the check valve according to the control signal from the controller 50 .
- the hydraulic oil can be prevented from flowing backward from the rod-side oil chamber of the screed lift cylinder 25 toward the hydraulic oil tank T.
- the hydraulic fluid flowing out from the head side oil chamber of the screed lift cylinder 25 is discharged to the hydraulic fluid tank T without passing through the screed lift control valve 35 .
- the screed lift cylinder 25 contracts.
- the screed lift control valve 35 is not used and the state shown in FIG. 3 is maintained.
- the switching valve 35a is switched to the second position, which does not include the check valve, according to the control signal from the controller 50.
- FIG. As a result, the hydraulic fluid in the rod-side oil chamber of the screed lift cylinder 25 can flow out toward the hydraulic fluid tank T. Therefore, the screed lift cylinder 25 expands due to the weight of the screed 3, and the hydraulic fluid in the rod-side oil chamber of the screed lift cylinder 25 is discharged to the hydraulic fluid tank T through the switching valve 35a and the relief valve 35b.
- the switching valve 35a and the relief valve 35b control the up-and-down movement of the screed 3 due to changes in the lifting force generated when the asphalt finisher 100 moves and paves the road (that is, the force with which the pavement material tries to lift the screed 3). come true. Specifically, when the screed 3 rises due to an increase in lift, the screed lift cylinder 25 contracts. In this case, the hydraulic oil discharged from the cylinder pump 14M flows into the rod-side oil chamber of the screed lift cylinder 25 through the conduit C3, the screed lift control valve 35, and the switching valve 35a. On the other hand, when the screed 3 descends due to a decrease in lift, the screed lift cylinder 25 extends.
- the screed expansion/contraction part F8 is configured so that the expansion/contraction screed 31 can be expanded and contracted in the vehicle width direction (Y-axis direction) using hydraulic oil supplied from the hydraulic pressure source 14 .
- the screed telescopic part F8 includes a screed telescopic cylinder 27, a screed telescopic control valve 37, a pilot check valve 37P, and a relief valve 37V.
- the screed expansion/contraction control valve 37 operates according to a control signal from the controller 50 to control the flow rate and flow direction of hydraulic oil supplied to the screed expansion/contraction cylinder 27 .
- the screed expansion/contraction control valve 37 includes a left screed expansion/contraction control valve 37L and a right screed expansion/contraction control valve 37R.
- the left screed telescoping control valve 37L When retracting the left telescoping screed 31L, the left screed telescoping control valve 37L causes the hydraulic oil discharged by the cylinder pump 14M to flow into the rod side oil chamber of the left screed telescoping cylinder 27L, and the left screed telescoping cylinder 27L. The hydraulic oil flowing out from the head side oil chamber is discharged to the hydraulic oil tank T. In this case, the left telescoping screed cylinder 27L is retracted and the left telescoping screed 31L is retracted. The same applies to the case where the right telescopic screed 31R is retracted by the right screed telescopic control valve 37R.
- the left screed telescoping control valve 37L causes the working oil discharged by the cylinder pump 14M to flow into the head side oil chamber of the left screed telescoping cylinder 27L, and the left screed telescoping cylinder 27L. Hydraulic oil flowing out from the rod-side oil chamber of 27L is discharged to the hydraulic oil tank T. In this case, the left screed telescopic cylinder 27L is extended and the left telescopic screed 31L is pushed out. The same applies to the case where the right telescopic screed 31R is retracted by the right screed telescopic control valve 37R.
- the pilot check valve 37P is configured to prevent the screed telescopic cylinder 27 from unintentionally moving due to an external force.
- the pilot check valve 37P includes pilot check valves 37PaL, 37PaR, 37PbL and 37PbR.
- the pilot check valve 37PaL operates when the left screed telescopic control valve 37L operates in response to an operator's operation and the hydraulic oil discharged from the cylinder pump 14M flows into the head-side oil chamber of the left screed telescopic cylinder 27L. Hydraulic oil in the rod-side oil chamber of the left screed telescopic cylinder 27L is allowed to flow toward the hydraulic oil tank T as long as possible.
- the pilot check valve 37PaL prohibits the hydraulic oil in the rod-side oil chamber of the left screed telescopic cylinder 27L from flowing toward the hydraulic oil tank T in other cases.
- the relief valve 37V is configured to prevent members associated with the telescopic screed 31 from being destroyed by an excessive external force acting in the direction of retracting the telescopic screed 31 .
- the relief valve 37V includes a left relief valve 37VL and a right relief valve 37VR.
- the left relief valve 37VL receives an excessive external force acting in the direction of contracting the left screed telescopic cylinder 27L and the pressure of the hydraulic oil in the head side oil chamber of the left screed telescopic cylinder 27L rises excessively, the head side Hydraulic oil in the oil chamber is allowed to flow out to the hydraulic oil tank T. As a result, the left screed telescoping cylinder 27L contracts to absorb some of the external force and prevent damage to the left telescoping screed 31L. The same applies to the right relief valve 37VR.
- FIG. 4 is a diagram explaining an example of a method of controlling the driving force of the front wheels 6.
- FIG. 4 includes a control law 400 showing the relationship between the weight of pavement material inside the hopper 2 and the relief pressure (set value) of the relief valve RV set by the controller 50 .
- 5A to 5D are front views showing the state of the pavement material PM inside the hopper 2.
- FIG. 5A shows the state of the pavement material PM inside the hopper 2 immediately after the pavement material PM is supplied by the dump truck.
- FIG. 5B shows the state of the pavement material PM inside the hopper 2 when the amount has decreased with respect to the state of FIG. 5A.
- FIG. 5C shows the state of the pavement material PM inside the hopper 2 when the hopper 2 is closed to some extent (specifically, about half) due to the relative decrease in the amount of the pavement material PM inside the hopper 2.
- FIG. 5D shows the amount of pavement material PM inside the hopper 2 when the amount of pavement material PM inside the hopper 2 is further reduced from the state of FIG. 5C and the hopper 2 is completely closed.
- the paving material PM in the hopper 2 is hatched with a satin finish.
- 5A also shows the base portion 1BF of the tractor 1, the front wheels 6 (the left front wheel 6L and the right front wheel 6R), and the hopper cylinders 24 (the left hopper cylinder 24L and the right hopper cylinder 24R), but FIGS. In 5D these are omitted.
- 5A, 5C, and 5D the entrance OP of the conveying path CP provided on the front surface 1FW of the tractor 1 is buried in the pavement material PM and cannot be directly seen from the front (that is, it is not exposed). A portion is represented by a dashed line.
- the pavement material PM is surrounded by the inside of the hopper 2, specifically the front face 1FW of the tractor 1 and the left and right hopper wings 2W (left hopper wing 2WL and right hopper wing 2WR). are housed in a closed space.
- a sufficient amount of pavement material PM is accumulated inside the hopper 2 immediately after the pavement material PM is supplied from the dump truck.
- the amount of pavement material PM inside the hopper 2 decreases as the asphalt pavement construction by the asphalt finisher 100 progresses.
- the pavement material PM is reduced from the central portion inside the hopper 2 where the conveyor CV is provided. Therefore, as shown in FIGS. 5C and 5D, when the amount of pavement material inside the hopper 2 decreases to a certain extent, the hopper 2 is closed, and the pavement material PM at both left and right ends inside the hopper 2 is collected in the center. be done. As a result, it is possible to prevent the paving material PM from remaining at the left and right ends inside the hopper 2 .
- the hopper 2 may be closed by the operation of the operator who monitors the internal conditions of the hopper 2, as described above. Moreover, the hopper 2 may be automatically closed without depending on the operator's operation. In this case, the controller 50 may determine whether or not to close the hopper 2 according to the amount of pavement material inside the hopper 2 (estimated value) estimated based on the output of the space recognition device CM. . Further, the controller 50 may determine the closing amount (angle) of the hopper 2 based on the amount of pavement material (estimated value). Then, the controller 50 may control the hopper driving section F6 (hopper control valve 34) so that the expansion/contraction amount of the hopper cylinder 24 becomes the determined closing amount of the hopper 2.
- the driving force of the front wheels 6 reaches the maximum value between the front wheels 6 and the roadbed. It can be greater than the frictional force. This is because the load on the front wheels 6 decreases as the amount of pavement material PM inside the hopper 2 decreases as the construction work progresses. As a result, there is a possibility that the front wheels 6 will slip (wheel spin) and damage the roadbed, or the driving force of the asphalt finisher 100 will decrease.
- the controller 50 (front wheel driving force control section 50B) adjusts the driving force of the front wheels 6 according to the amount of pavement material inside the hopper 2 .
- the front wheel driving force control unit 50B adjusts the driving force of the front wheels 6 so that the driving force of the front wheels 6 decreases as the amount of pavement material inside the hopper 2 decreases.
- the controller 50 can prevent the driving force of the front wheels 6 from becoming excessively larger than the maximum frictional force of the front wheels 6 when the weight of the pavement material inside the hopper 2 is relatively reduced. . Therefore, in the present embodiment, the controller 50 can suppress damage to the roadbed caused by the slippage of the front wheels 6, reduction in driving force of the asphalt finisher 100, and the like.
- the controller 50 controls the relief pressure of the relief valve RV so that the relief pressure of the relief valve RV decreases as the weight of the pavement material inside the hopper 2 decreases in accordance with the control law 400.
- the pressure (set point) may be controlled.
- the pressure (maximum value) of the hydraulic oil supplied to the front-wheel drive motor 22 through the oil passage between the front-wheel drive pump 14F and the front-wheel drive motor 22 is reduced by the weight of the pavement material inside the hopper 2.
- the controller 50 adjusts the driving force of the front wheels 6 by controlling the tilt angle of the swash plate of the front wheel pump 14F in addition to controlling the relief pressure of the relief valve RV.
- the controller 50 specifically sets the target value of the driving force of the front wheels 6 in accordance with the weight of the pavement material inside the hopper 2, and operates the relief valve to achieve the target value.
- the control amount of the RV and the front wheel running pump 14F (regulator) may be adjusted.
- a control law representing the relationship between the driving force (target value) of the front wheels 6 and the control amount (relief pressure or tilt angle) may be defined in advance.
- the asphalt finisher 100 includes a controller 50 (front wheel driving force control section 50B) that controls the driving force of the front wheels 6 of the tractor 1 based on the weight of the pavement material in the hopper 2.
- the front wheel driving force control section 50B changes the driving force of the front wheels 6 of the tractor 1 according to the change in the weight of the pavement material inside the hopper 2 .
- the asphalt finisher 100 (controller 50) can adjust the driving force of the front wheels 6 in accordance with the decrease in the amount of pavement material inside the hopper 2 as the asphalt pavement construction work progresses. Therefore, the asphalt finisher 100 appropriately reduces the driving force of the front wheels 6 in accordance with the reduction of the load on the front wheels 6 as the amount of pavement material inside the hopper 2 decreases, thereby suppressing the slippage of the front wheels 6. can be done. Therefore, the asphalt finisher 100 can suppress damage to the roadbed due to slippage of the front wheels 6 .
- the front wheel driving force control section 50B may reduce the driving force of the front wheels 6 when the weight of the pavement material inside the hopper 2 is reduced.
- the asphalt finisher 100 reduces the driving force of the front wheels 6 as the weight of the pavement material inside the hopper 2 decreases, that is, the load on the front wheels 6 decreases. 6 slip can be suppressed.
- the front wheel driving force control unit 50B drives the front wheels 6 so as to maintain the target value that is changed according to the change in the weight of the pavement material inside the hopper 2 while the tractor 1 is running. You can control your power.
- the asphalt finisher 100 (controller 50) can appropriately adjust the driving force of the front wheels 6 according to changes in the weight of the pavement material inside the hopper 2.
- the front wheel driving force control section 50B may control the driving force of the front wheels 6 by adjusting the relief pressure of the relief valve RV. Further, in the present embodiment, the front wheel driving force control section 50B may control the driving force of the front wheels 6 by adjusting the angle (tilt angle) of the swash plate of the front wheel running pump 14F.
- the asphalt finisher 100 (controller 50) specifically controls the driving force of the front wheels 6 by controlling the relief pressure of the relief valve RV and the tilt angle of the swash plate of the front wheel pump 14F. can be adjusted.
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Abstract
Description
トラクタと、
前記トラクタの前側に設置されて舗装材を受け入れるホッパと、
前記ホッパ内の前記舗装材を前記トラクタの後側へ搬送するコンベアと、
前記コンベアにより搬送された前記舗装材を前記トラクタの後側で敷き拡げるスクリュと、
前記スクリュにより敷き拡げられた前記舗装材を前記スクリュの後側で敷き均すスクリードと、
前記ホッパ内の前記舗装材の重量に基づき、前記トラクタの前輪の駆動力を制御する制御部と、を備える、
アスファルトフィニッシャが提供される。 To achieve the above objectives, in one embodiment of the present disclosure,
a tractor;
a hopper located in front of the tractor for receiving paving material;
a conveyor for transporting the paving material in the hopper to the rear of the tractor;
a screw for spreading the pavement material conveyed by the conveyor on the rear side of the tractor;
a screed for evenly spreading the pavement material spread by the screw behind the screw;
a control unit that controls the driving force of the front wheels of the tractor based on the weight of the pavement material in the hopper;
An asphalt finisher is provided.
まず、図1を参照して、本実施形態に係るアスファルトフィニッシャ100の全体構成について説明する。 [overall structure]
First, referring to FIG. 1, the overall configuration of an
次に、図1A、図1Bに加え、図2を参照して、コントローラ50の機能構成について説明する。具体的には、前輪6の駆動力の調整機能(以下、「前輪駆動力調整機能」)に関するコントローラ50の機能構成について説明する。 [Function configuration]
Next, the functional configuration of the
次に、図3を参照して、アスファルトフィニッシャ100に搭載される油圧システムについて説明する。 [Hydraulic system]
Next, referring to FIG. 3, a hydraulic system mounted on the
次に、図1~図3に加えて、図4、図5を参照して、コントローラ50による前輪6の駆動力の調整方法について具体的に説明する。 [Specific example of a method for adjusting the driving force of the front wheels]
Next, referring to FIGS. 4 and 5 in addition to FIGS. 1 to 3, a method for adjusting the driving force of the
次に、本実施形態に係るアスファルトフィニッシャ100の作用について説明する。 [Action]
Next, the operation of the
2 ホッパ
2W ホッパウイング
2WL 左ホッパウイング
2WR 右ホッパウイング
3 スクリード
3A レベリングアーム
5 後輪
6 前輪
14 油圧源
14C チャージポンプ
14E エンジン
14F 前輪走行用ポンプ(油圧ポンプ)
14M シリンダ用ポンプ
14R 後輪走行用ポンプ
14S コンベア・スクリュ用ポンプ
20L 左後輪走行用モータ
20La チェック弁
20Lb リリーフ弁
20R 右後輪走行用モータ
20Ra チェック弁
20Rb リリーフ弁
21 コンベア・スクリュ用モータ
21CL 左コンベア用モータ
21CR 右コンベア用モータ
21SL 左スクリュ用モータ
21SR 右スクリュ用モータ
22 前輪走行用モータ(油圧モータ)
23 レベリングシリンダ
23L 左レベリングシリンダ
23R 右レベリングシリンダ
24 ホッパシリンダ
24L 左ホッパシリンダ
24R 右ホッパシリンダ
25 スクリードリフトシリンダ
25L 左スクリードリフトシリンダ
25R 右スクリードリフトシリンダ
27 スクリード伸縮シリンダ
27L 左スクリード伸縮シリンダ
27R 右スクリード伸縮シリンダ
30 メインスクリード
31 伸縮スクリード
33 レベリング用制御弁
33L 左レベリング用制御弁
33R 右レベリング用制御弁
33P、33PaL、33PaR、33PbL、33PbR パイロットチェック弁
34 ホッパ用制御弁
34L 左ホッパ用制御弁
34R 右ホッパ用制御弁
34P、34PL、34PR パイロットチェック弁
35 スクリードリフト用制御弁
35a 切替弁
35b リリーフ弁
35c 切替弁
37 スクリード伸縮用制御弁
37P、37PaL、37PaR、37PbL、37PbR パイロットチェック弁
37V リリーフ弁
37VL 左リリーフ弁
37VR 右リリーフ弁
40 サイドプレート
41 伸縮モールドボード
42 スクリードステップ
43 リテーニングプレート
50 コントローラ
50A 舗装材重量取得部
50B 前輪駆動力制御部(制御部)
100 アスファルトフィニッシャ
CM 空間認識装置
CP 搬送通路
CV コンベア
F1 後輪駆動部
F2 コンベア・スクリュ駆動部
F3 前輪駆動部
F4 操舵・締め固め装置駆動部
F5 レベリング部
F6 ホッパ駆動部
F7 スクリードリフト部
F8 スクリード伸縮部
OC オイルクーラ
OP 入口
RV リリーフ弁
SC スクリュ
SCLE 左延長スクリュ
SCLM 左メインスクリュ
SCRE 右延長スクリュ
SCRM 右メインスクリュ
V0 減速機切替弁
V1C コンベア用制御弁
V1CL 左コンベア用制御弁
V1CR 右コンベア用制御弁
V1S スクリュ用制御弁
V1SL 左スクリュ用制御弁
V1SR 右スクリュ用制御弁
V2 前輪走行用弁 1
23
100 Asphalt finisher CM Space recognition device CP Conveyance passage CV Conveyor F1 Rear wheel drive F2 Conveyor screw drive F3 Front wheel drive F4 Steering and compaction device drive F5 Leveling F6 Hopper drive F7 Screed lift F8 Screed extension part OC Oil cooler OP Inlet RV Relief valve SC Screw SCLE Left extension screw SCLM Left main screw SCRE Right extension screw SCRM Right main screw V0 Reducer switching valve V1C Conveyor control valve V1CL Left conveyor control valve V1CR Right conveyor control valve V1S Screw V1SL Left screw control valve V1SR Right screw control valve V2 Front wheel travel valve
Claims (6)
- トラクタと、
前記トラクタの前側に設置されて舗装材を受け入れるホッパと、
前記ホッパ内の前記舗装材を前記トラクタの後側へ搬送するコンベアと、
前記コンベアにより搬送された前記舗装材を前記トラクタの後側で敷き拡げるスクリュと、
前記スクリュにより敷き拡げられた前記舗装材を前記スクリュの後側で敷き均すスクリードと、
前記ホッパ内の前記舗装材の重量に基づき、前記トラクタの前輪の駆動力を制御する制御部と、を備える、
アスファルトフィニッシャ。 a tractor;
a hopper located in front of the tractor for receiving paving material;
a conveyor for transporting the paving material in the hopper to the rear of the tractor;
a screw for spreading the pavement material conveyed by the conveyor on the rear side of the tractor;
a screed for evenly spreading the pavement material spread by the screw behind the screw;
a control unit that controls the driving force of the front wheels of the tractor based on the weight of the pavement material in the hopper;
asphalt finisher. - 前記制御部は、前記重量の変化に合わせて、前記トラクタの前輪の駆動力を変化させる、
請求項1に記載のアスファルトフィニッシャ。 The control unit changes the driving force of the front wheels of the tractor according to the change in the weight.
The asphalt finisher according to claim 1. - 前記制御部は、前記トラクタの走行中において、前記重量の変化に合わせて変更される目標値を維持するように前記前輪の駆動力を制御する、
請求項2に記載のアスファルトフィニッシャ。 The control unit controls the driving force of the front wheels so as to maintain a target value that is changed according to changes in the weight while the tractor is traveling.
The asphalt finisher according to claim 2. - 前記制御部は、前記重量が減少すると、前記前輪の駆動力を減少させる、
請求項2又は3に記載のアスファルトフィニッシャ。 The control unit reduces the driving force of the front wheels when the weight is reduced.
The asphalt finisher according to claim 2 or 3. - 前記前輪を駆動する油圧モータと、
前記油圧モータに作動油を供給する油圧ポンプと、
前記油圧ポンプと前記油圧モータとの間の油路に設けられるリリーフ弁とを備え、
前記制御部は、前記リリーフ弁のリリーフ圧を調整することにより、前記前輪の駆動力を制御する、
請求項1乃至3の何れか一項に記載のアスファルトフィニッシャ。 a hydraulic motor that drives the front wheels;
a hydraulic pump that supplies hydraulic oil to the hydraulic motor;
a relief valve provided in an oil passage between the hydraulic pump and the hydraulic motor;
The control unit controls the driving force of the front wheels by adjusting the relief pressure of the relief valve.
The asphalt finisher according to any one of claims 1 to 3. - 前記制御部は、前記油圧ポンプの斜板の角度を調整することにより、前記前輪の駆動力を制御する、
請求項5に記載のアスファルトフィニッシャ。 The control unit controls the driving force of the front wheels by adjusting the angle of the swash plate of the hydraulic pump.
The asphalt finisher according to claim 5.
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
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EP22780819.3A EP4317582A4 (en) | 2021-03-30 | 2022-03-28 | Asphalt finisher |
CN202280020082.9A CN117321267A (en) | 2021-03-30 | 2022-03-28 | Asphalt rolling machine |
JP2023511306A JPWO2022210608A1 (en) | 2021-03-30 | 2022-03-28 |
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JP2021-057823 | 2021-03-30 | ||
JP2021057823 | 2021-03-30 |
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WO2022210608A1 true WO2022210608A1 (en) | 2022-10-06 |
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Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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PCT/JP2022/015201 WO2022210608A1 (en) | 2021-03-30 | 2022-03-28 | Asphalt finisher |
Country Status (4)
Country | Link |
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EP (1) | EP4317582A4 (en) |
JP (1) | JPWO2022210608A1 (en) |
CN (1) | CN117321267A (en) |
WO (1) | WO2022210608A1 (en) |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6414204U (en) * | 1987-07-14 | 1989-01-25 | ||
JPH0477609U (en) * | 1990-11-19 | 1992-07-07 | ||
JP2020063650A (en) | 2019-03-29 | 2020-04-23 | 住友建機株式会社 | Asphalt finisher |
-
2022
- 2022-03-28 WO PCT/JP2022/015201 patent/WO2022210608A1/en active Application Filing
- 2022-03-28 EP EP22780819.3A patent/EP4317582A4/en active Pending
- 2022-03-28 JP JP2023511306A patent/JPWO2022210608A1/ja active Pending
- 2022-03-28 CN CN202280020082.9A patent/CN117321267A/en active Pending
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS6414204U (en) * | 1987-07-14 | 1989-01-25 | ||
JPH0477609U (en) * | 1990-11-19 | 1992-07-07 | ||
JP2020063650A (en) | 2019-03-29 | 2020-04-23 | 住友建機株式会社 | Asphalt finisher |
Non-Patent Citations (1)
Title |
---|
See also references of EP4317582A4 |
Also Published As
Publication number | Publication date |
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CN117321267A (en) | 2023-12-29 |
EP4317582A4 (en) | 2024-08-28 |
JPWO2022210608A1 (en) | 2022-10-06 |
EP4317582A1 (en) | 2024-02-07 |
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