JP2008248523A - Working vehicle - Google Patents

Working vehicle Download PDF

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Publication number
JP2008248523A
JP2008248523A JP2007089001A JP2007089001A JP2008248523A JP 2008248523 A JP2008248523 A JP 2008248523A JP 2007089001 A JP2007089001 A JP 2007089001A JP 2007089001 A JP2007089001 A JP 2007089001A JP 2008248523 A JP2008248523 A JP 2008248523A
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JP
Japan
Prior art keywords
work
variable
traveling
output
engine
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
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JP2007089001A
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Japanese (ja)
Inventor
Minoru Wada
稔 和田
Original Assignee
Komatsu Ltd
株式会社小松製作所
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Application filed by Komatsu Ltd, 株式会社小松製作所 filed Critical Komatsu Ltd
Priority to JP2007089001A priority Critical patent/JP2008248523A/en
Publication of JP2008248523A publication Critical patent/JP2008248523A/en
Pending legal-status Critical Current

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Abstract

An engine output is distributed to a work machine and a traveling device so as to be suitable for a mode of loading work which varies from work site to work site.
A variable displacement hydraulic pump 27 that transmits output of an engine 21 to cylinders 13 and 15 of a work machine, a variable clutch 22 that transmits output of the engine 21 to a torque converter 23 of a traveling device, and operation of a wheel loader. A work setting dial 60 for adjusting the travel distance of the traveling device when the work implement is working, and a variable displacement hydraulic pump based on the input received by the work setting dial 60 27 and a controller 200 that controls the variable degree of the variable clutch 22.
[Selection] Figure 7

Description

  The present invention relates to a technique for distributing output of an engine to a work machine and a travel device according to a mode of a loading operation that differs for each work site in a work vehicle including a work machine and a travel device.

  For example, in Patent Documents 1 and 2, in a work vehicle including a work machine and a traveling device, a hydraulic pump driven by an engine is a variable displacement hydraulic pump, and whether or not the work vehicle is under excavation work. Describes a technique for reducing the power loss by making the output to the work machine variable. Similarly, Patent Document 3 describes a technology that similarly includes a variable displacement hydraulic pump, automatically determines the operating state of the work vehicle, and adjusts the output to the work machine and the engine speed.

Furthermore, in a work vehicle equipped with a work machine and a traveling device, there is a technique that uses a clutch that transmits the output of the engine to the traveling device as a variable clutch, and suppresses the output to the traveling device, and outputs a larger output by the working machine. .
JP 2004-251441 A JP 2006-348742 A JP 2006-169974 A

  In each of Patent Documents 1, 2, and 3, the output to the working machine can be suppressed by the variable displacement hydraulic pump, but the output to the traveling device cannot be adjusted. Conversely, in a work vehicle having a variable clutch, output to the traveling device can be suppressed, but output to the work implement cannot be adjusted. That is, in the conventional technique, only one of them is controlled, and both are not actively controlled.

  By the way, in an operation of loading an object cut by excavating with a work vehicle onto a dump truck or the like, there are restrictions on how to arrange the work vehicle and the dump truck according to the situation of the work site. Therefore, there are several work modes depending on the positional relationship between them. If the engine output can be distributed to the work equipment and the traveling device according to each work mode, both improvement in fuel consumption and reduction in work time can be realized, but the conventional technology does not perform such control. .

  Also, the driver who actually moves the work vehicle knows the work that the work vehicle actually performs, and if the driver gives some command, the state of the engine is detected by a sensor or the like. There is no need to monitor.

  Therefore, an object of the present invention is to distribute the engine output to the work implement and the traveling device so as to be suitable for different loading work modes for each work site.

  A work vehicle according to an embodiment of the present invention is a work vehicle (1) including a work machine (10) driven by an engine (21) and a traveling device (40), and outputs the engine to the work machine. A first transmission means (27) having a variable output to be transmitted to the work machine, and a transmission means for transmitting the output of the engine to a travel device, the travel device. A second transmission means (22) having a variable output transmitted to the vehicle and an input device operable by a driver of the work vehicle, wherein the operation speed of the work implement is adjusted with respect to the travel speed of the travel device And a control device (200) for controlling the transmission degree of the output by the first and second transmission means based on the input received by the input device.

  In a preferred embodiment, the input device may continuously receive an input for adjusting a travel distance of the travel device when the work machine is working.

  In a preferred embodiment, the first transmission means is a variable displacement hydraulic pump, and the output transmitted to the working machine is variable by changing the discharge amount of the pressure oil discharged by the variable displacement hydraulic pump. You may make it.

  In a preferred embodiment, the second transmission means may be a variable clutch, and the output transmitted to the travel device may be variable by changing the engagement rate of the variable clutch.

  Hereinafter, a work vehicle according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 shows a side view of a wheel loader 1 which is an example of a work vehicle including a traveling device and a work machine, and FIG. 2 shows a plan view thereof.

  A wheel loader 1 shown in FIGS. 1 and 2 includes a work machine 10 and a traveling device 40, and an engine room 3 that houses the cab 2 and the power unit 20 is provided on the traveling device 40. The traveling device 40 includes a rear vehicle body 5 including rear wheels 4 and 4 and a front frame 7 including front wheels 6 and 6. A work machine 10 is attached in front of the front frame 7. The rear vehicle body 5 and the front frame 7 are attached to a left and right swingable by a center pin 8 to constitute an articulate structure. In FIG. 2, the rear vehicle body 5 and the front frame 7 are connected by a pair of left and right steering cylinders 9 and 9, and the rear vehicle body 5 and the front frame 7 are expanded and contracted by expanding and contracting the left and right steering cylinders 9 and 9. The center pin 8 is swung left and right around the center pin 8 and steered.

  The work machine 10 includes a boom 11 whose base end is swingably attached to the front frame 7, and a bucket 12 that is swingably attached to the distal end of the boom 11. The front frame 7 and the boom 11 are connected by a pair of boom cylinders 13 and 13, and the boom 11 swings by extending and contracting the boom cylinders 13 and 13. Further, the work machine 10 includes a tilt arm 14 that is swingably supported by the boom 11 at a substantially central portion thereof, a bucket cylinder 15 that connects the base end portion of the tilt arm 14 and the front frame 7, and a tilt A tilt rod 16 that connects the tip of the arm 14 and the bucket 12 is provided. By expanding and contracting the bucket cylinder 15, the bucket 12 swings.

  In FIG. 1, a power unit 20 is mounted in the engine room 3. The power unit 20 includes an engine 21, a variable clutch 22 that transmits driving power in a changeable manner, a torque converter 23, a forward / reverse switching, a transmission 24 that can switch a plurality of shift stages, a distributor 25, a rear wheel 4, and a front wheel. 6 is composed of speed reducers 26, 26, and the like.

  The wheel loader 1 includes a variable displacement hydraulic pump 27 that is driven by the engine 21 and supplies pressure oil to the boom cylinder 13 and the bucket cylinder 15. The amount of oil supplied by the variable displacement hydraulic pump 27 can be changed. By varying the oil amount, the power transmitted to the boom cylinder 13 and the bucket cylinder 15 varies.

  In the cab 2, a forward / reverse lever 30 and a work setting dial 60 are provided. The forward / reverse lever 30 may be other types such as a switch type. Details of the work setting dial 60 will be described later.

  Next, an outline of excavation work and loading work by the wheel loader 1 will be described.

  When performing the excavation work, first, the operator of the wheel loader 1 sets the forward / reverse lever 30 to “forward”, lowers the boom 11, and positions the bucket 12 at the excavable position facing the front. Thereby, the wheel loader 1 moves forward while keeping the bucket 12 at the excavable position, and the blade edge of the bucket 12 rushes into the object. Here, by operating the bucket cylinder 15 to tilt the bucket 12 back, the object can be scooped into the bucket 12.

  Next, for loading work, when the boom cylinder 13 is extended to raise the boom 11 and the driver sets the forward / reverse lever 30 to “reverse”, the wheel loader 1 moves backward with the bucket 12 raised. . Thereafter, the driver sets the forward / reverse lever 30 to “advance” again, advances the wheel loader 1 closer to the dump truck, approaches it, operates the bucket cylinder 15 at a predetermined position, and dumps the bucket 12. Then load the object onto the dump truck bed.

  The basic operation of the wheel loader 1 is as described above. However, the positional relationship between the dump truck and the excavation object with respect to the wheel loader 1 may be limited due to various conditions at each work site. Therefore, there are a plurality of work modes as described below according to the positional relationship between the dump truck and the excavation object with respect to the wheel loader 1.

  The first work mode shown in FIG. 3 is called “V-shape”. “V shape” is a name given because the trajectory that moves when the wheel loader 1 repeats excavation and loading on a dump truck becomes “V-shaped”.

  In the “V shape”, the following (1) to (4) are repeated. That is, as shown in FIG. 1A, in (1), the wheel loader 1 is advanced toward the excavation object, and the object is scooped into the bucket 12 by the basic operation described above. Next, in (2), the boom 11 is raised while the wheel loader 1 is moved backward while the bucket 12 is tilted up. The work efficiency is improved by raising the boom 11 during reverse travel. Next, as shown in FIG. B, in (3), with the boom 11 raised, the vehicle moves forward toward the dump truck D stopped beside the object to be excavated, and the dump truck D as described above. Load the object on the loading platform. In (4), the vehicle moves backward toward the start position.

  The second working mode shown in FIG. 4 is called “I cross”. “I cross” is a name given because the trajectory of movement of the wheel loader 1 and the dump truck becomes “a crossed I shape” when the wheel loader 1 repeats excavation and loading onto the dump truck. It is.

  In “I cross”, the following (1) to (6) are repeated. That is, as shown in FIG. 1A, in (1), the wheel loader 1 is advanced toward the excavation object, and the object is scooped into the bucket 12 by the basic operation described above. Next, in (2), while the bucket 12 is tilted up, the boom loader 11 is raised while the wheel loader 1 is moved backward straight. As in the case of “V-shape”, the working efficiency is improved by raising the boom 11 during reverse travel. Next, as shown in Fig. B, in (3), the dump truck D moves from the standby position to the front of the wheel loader 1. In (4), the vehicle moves forward toward the dump truck D with the boom 11 raised, and loads the object onto the loading platform of the dump truck D in the manner described above. In (5), the wheel loader 1 moves backward. In (6), the dump truck D returns to the standby position.

  The third working mode shown in FIG. 5 is called load and carry (hereinafter referred to as L & C). “L & C” is an operation mode when the position of the excavation target and the place where the scooped target is dumped are separated. That is, in “L & C”, the wheel loader 1 loads an object (Load), and then carries the object loaded in forward travel (Carry). In order to perform work efficiently, the boom 11 is raised during forward traveling.

  In any of the above-described aspects, the boom 11 is raised while the wheel loader 1 is moving horizontally by the traveling device 40 after scooping the object into the bucket 12 in order to shorten the work time. At this time, the movement distance differs between “V shape” and “I cross” and “L & C”. That is, in the “V shape” and “I cross”, it is more efficient that the moving distance of the wheel loader 1 in the horizontal direction is shorter. In “L & C”, the moving distance is determined by the distance between the excavation site and the place where the scooped object is dumped.

  In any work mode, if the boom 11 is raised to a necessary height so that the bucket 12 can be dumped immediately after the movement in the horizontal direction is finished, work efficiency is improved. On the other hand, the boom 11 does not have to be lifted up in the middle of the movement in the horizontal direction, and it is sufficient if the boom 11 is at a necessary height when the movement is finished. Therefore, in “V shape” and “I cross”, it is necessary to raise the boom 11 at a high speed with respect to a short horizontal movement distance, and in “L & C”, while moving a long horizontal movement distance. In addition, the boom 11 may be raised slowly.

  By the way, in the wheel loader 1 according to the present embodiment, the work implement 10 and the traveling device 40 are driven based on the output of one engine 21. Then, as will be described later, the transmission ratios of both the power transmitted to the work implement 10 and the traveling power transmitted to the traveling device 40 can be changed. By changing both transmission rates, even when the engine speed is the same, it is possible to change the traveling speed and the speed at which the work machine operates (work machine speed) by changing the output distribution. Therefore, in the present embodiment, the output of the engine 21 is distributed to the work implement 10 and the traveling device 40 at an appropriate ratio for each work mode.

  In the present embodiment, the distribution ratio is adjusted by the driver adjusting the work setting dial 60 provided in the cab 2.

  FIG. 6 shows an example of the work setting dial 60 according to the present embodiment. The work setting dial 60 shown in the figure is a stepless rotary dial that a driver rotates with a knob 61. Around the dial, as a guideline for setting the dial position, “normal” at the center of the movable range, “V shape” on the left side, “L & C” on the right side, and work mode display 62 are described. The driver sets the dial 60 according to the work mode, thereby distributing torque suitable for each work mode. That is, as the dial knob 61 is turned to the left, the distribution becomes more suitable for “V shape”, and as the dial is turned to the right, the distribution becomes more suitable for “L & C”.

  In addition to the work mode display 62 of the present embodiment, other descriptions that serve as a guide for setting the position of the knob 61 may be provided around the work setting dial 60. This description may be, for example, a matching distance or a number indicating a simple distribution level. Here, the matching distance is a distance that the wheel loader moves while the boom is raised. By changing the above distribution rate, the matching distance also changes.

  Furthermore, in the present embodiment, the dial is used as a means for the driver to set in order to determine the distribution rate, but the present invention is not limited to this, and other setting means may be used. For example, a slide-type input unit that continuously sets a distribution ratio in a stepless manner may be used, or discrete values may be set using a dial-type, slide-type, or push-button type input unit.

  FIG. 7 is a functional block diagram relating to the control mechanism of the wheel loader 1 according to the present embodiment.

  The wheel loader 1 includes a controller 200 that determines a distribution ratio of engine output.

  The controller 200 detects the knob position of the work setting dial 60. Then, the controller 200 determines the discharge flow rate of the variable displacement hydraulic pump 27 and the engagement rate of the variable clutch 22 according to the detected knob position of the work setting dial 60. Furthermore, the controller 200 controls the variable displacement hydraulic pump 27 and the variable clutch 22 so that the discharge flow rate and the engagement rate determined here are obtained.

  The variable displacement hydraulic pump 27 discharges pressure oil having a discharge flow rate determined by the control of the controller 200 and sends it to the boom cylinder 13 and the bucket cylinder 15.

  The variable clutch 22 transmits traveling power to the torque converter 23 at an engagement rate determined by the control of the controller 200.

  Here, a method when the controller 200 determines the discharge flow rate of the variable displacement hydraulic pump 27 and the engagement rate of the variable clutch 22 will be described.

  FIG. 8 is a graph showing the discharge flow rate of the variable displacement hydraulic pump 27 and the engagement rate of the variable clutch 22 with respect to the knob position of the work setting dial 60. The controller 200 determines the discharge flow rate of the variable displacement hydraulic pump 27 and the engagement rate of the variable clutch 22 according to this graph.

  For example, if the knob position of the work setting dial 60 is “normal”, the controller 200 controls so that the discharge flow rate of the variable displacement hydraulic pump 27 and the engagement rate of the variable clutch 22 are both maximized.

  On the other hand, if the knob position of the work setting dial 60 is on the left “V-shape” side, the controller 200 maintains the discharge flow rate of the variable displacement hydraulic pump 27 in the maximum state, and the knob position is left. The variable clutch 22 is controlled so that the engagement rate decreases as the value goes to.

  On the other hand, if the knob position of the work setting dial 60 is on the right “L & C” side, the controller 200 maintains the engagement ratio of the variable clutch 22 in the maximum state, and the knob position is The variable displacement hydraulic pump 27 is controlled so that the discharge flow rate decreases toward the right.

  As a result, the driver can adjust the work setting dial 60 to control the output transmission rate for both the work implement and the travel device, and to realize the optimum distribution for the work device and the travel device. . As a result, it is possible to realize output distribution to work machines and traveling devices suitable for various work environments at various work sites by one dial operation. Furthermore, since the dial 60 is stepless, it is possible to finely adjust the distribution rate.

  The above-described embodiments of the present invention are examples for explaining the present invention, and are not intended to limit the scope of the present invention only to those embodiments. Those skilled in the art can implement the present invention in various other modes without departing from the gist of the present invention.

  For example, the clutch engagement rate such as the speed stage of the mechanical transmission can be controlled without using a variable clutch. Also, HST (Hydro Static Transmission) can be used. The HST used here includes, for example, a variable displacement hydraulic pump that is driven by an engine or a variable displacement hydraulic motor that is driven by pressure oil from a hydraulic pump and drives a traveling device. Then, by adjusting the work setting dial, the flow rate of the pressure oil in the variable displacement hydraulic pump or the variable displacement hydraulic motor is adjusted. Accordingly, the clutch engagement rate in the variable clutch corresponds to the pressure oil discharge flow rate in this case.

2 is a side view of the wheel loader 1. FIG. 2 is a plan view of the wheel loader 1. FIG. The 1st work mode (V shape) of excavation and loading work is shown. The 2nd work mode (I cross) of excavation and loading work is shown. The 3rd work mode (L & C) of excavation and loading work is shown. An example of the work setting dial 60 is shown. The functional block diagram regarding the control mechanism of the wheel loader 1 is shown. The discharge flow rate of the variable displacement hydraulic pump 27 and the engagement rate of the variable clutch 22 with respect to the position of the work setting dial 60 are shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wheel loader 10 Working machine 11 Boom 12 Bucket 13 Boom cylinder 15 Bucket cylinder 20 Power unit 21 Engine 22 Variable clutch 23 Torque converter 24 Transmission 25 Distributor 26 Decelerator 27 Variable capacity hydraulic pump 30 Forward / reverse lever 60 Work setting dial 61 Knob 62 Work mode display

Claims (4)

  1. A work vehicle (1) including a work machine (10) driven by an engine (21) and a traveling device (40),
    First transmission means (27) for transmitting the output of the engine to the work machine, wherein the output transmitted to the work machine is variable;
    Transmission means for transmitting the output of the engine to a traveling device, wherein the output transmitted to the traveling device is variable;
    An input device operable by a driver of the work vehicle, the input device (60) for adjusting a travel speed of the travel device and an operation speed of the work implement;
    A work vehicle comprising: a control device (200) that controls a degree of transmission of output by the first and second transmission means based on an input received by the input device.
  2.   The work vehicle according to claim 1, wherein the input device accepts an input for adjusting a travel distance of the travel device when the work machine is working.
  3.   The first transmission means is a variable displacement hydraulic pump, and an output transmitted to the working machine is variable by changing a discharge amount of pressure oil discharged from the variable displacement hydraulic pump. The work vehicle according to claim 1.
  4.   2. The work vehicle according to claim 1, wherein the second transmission unit is a variable clutch, and an output transmitted to the traveling device is variable by changing an engagement rate of the variable clutch.
JP2007089001A 2007-03-29 2007-03-29 Working vehicle Pending JP2008248523A (en)

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5236101B1 (en) * 2012-05-24 2013-07-17 株式会社小松製作所 Endless track construction machine
US8919474B2 (en) 2011-08-08 2014-12-30 Komatsu Ltd. Wheel loader
WO2015083753A1 (en) 2013-12-03 2015-06-11 株式会社小松製作所 Utility vehicle
WO2015129932A1 (en) * 2015-03-25 2015-09-03 株式会社小松製作所 Wheel loader
WO2018037936A1 (en) * 2016-08-26 2018-03-01 株式会社小松製作所 Wheel loader, and method for controlling wheel loader
WO2019207981A1 (en) * 2018-04-27 2019-10-31 株式会社小松製作所 Loading machine control device and loading machine control method
WO2019207982A1 (en) * 2018-04-27 2019-10-31 株式会社小松製作所 Loading machine control device and loading machine control method
US10570582B2 (en) 2016-11-23 2020-02-25 Caterpillar Inc. System and method for operating a material-handling machine

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8919474B2 (en) 2011-08-08 2014-12-30 Komatsu Ltd. Wheel loader
JP5236101B1 (en) * 2012-05-24 2013-07-17 株式会社小松製作所 Endless track construction machine
WO2013175654A1 (en) * 2012-05-24 2013-11-28 株式会社小松製作所 Caterpillar tread construction machine
CN103547471A (en) * 2012-05-24 2014-01-29 株式会社小松制作所 Caterpillar tread construction machine
KR101413556B1 (en) 2012-05-24 2014-07-01 가부시키가이샤 고마쓰 세이사쿠쇼 Crawler construction machine
US8805608B2 (en) 2012-05-24 2014-08-12 Komatsu Ltd. Crawler construction machine
CN103547471B (en) * 2012-05-24 2015-11-25 株式会社小松制作所 Caterpillar tread construction machine
WO2015083753A1 (en) 2013-12-03 2015-06-11 株式会社小松製作所 Utility vehicle
CN105074095B (en) * 2013-12-03 2017-10-13 株式会社小松制作所 Working truck
CN105074095A (en) * 2013-12-03 2015-11-18 株式会社小松制作所 Utility vehicle
US9650760B2 (en) 2013-12-03 2017-05-16 Komatsu Ltd. Work vehicle
EP2949822A4 (en) * 2013-12-03 2016-10-05 Komatsu Mfg Co Ltd Utility vehicle
JPWO2015083753A1 (en) * 2013-12-03 2017-03-16 株式会社小松製作所 Work vehicle
CN106661858A (en) * 2015-03-25 2017-05-10 株式会社小松制作所 Wheel loader
WO2016152994A1 (en) * 2015-03-25 2016-09-29 株式会社小松製作所 Wheel loader
JPWO2016152994A1 (en) * 2015-03-25 2017-07-20 株式会社小松製作所 Wheel loader
WO2015129932A1 (en) * 2015-03-25 2015-09-03 株式会社小松製作所 Wheel loader
US10876270B2 (en) 2015-03-25 2020-12-29 Komatsu Ltd. Wheel loader
CN106661858B (en) * 2015-03-25 2020-09-04 株式会社小松制作所 Wheel loader
CN108779845A (en) * 2016-08-26 2018-11-09 株式会社小松制作所 The control method of wheel loader and wheel loader
WO2018037936A1 (en) * 2016-08-26 2018-03-01 株式会社小松製作所 Wheel loader, and method for controlling wheel loader
US10570582B2 (en) 2016-11-23 2020-02-25 Caterpillar Inc. System and method for operating a material-handling machine
WO2019207981A1 (en) * 2018-04-27 2019-10-31 株式会社小松製作所 Loading machine control device and loading machine control method
WO2019207982A1 (en) * 2018-04-27 2019-10-31 株式会社小松製作所 Loading machine control device and loading machine control method

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