JP2014125943A - Working vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a working vehicle that can properly cope with a work traveling load along an intention of an operator, by the operation such as an accelerator adjustment and a shift change of a gear position.SOLUTION: A working vehicle is configured to supply an engine rotating power according to an accelerator opening to a traveling system (26) and a work system (40), to transmit and supply the power to a driving wheel (3) through a main transmission section (16, 17) enabling a shift change of a gear position by the traveling system (26), and to enable work traveling while receiving a traveling load to this driving wheel (3). The working vehicle is characterized by providing vehicle speed characteristics for the load obtained as the amount of vehicle speed drop from non-load by traveling over a total load range under each condition of the accelerator opening and the gear position, and also providing a work traveling evaluation system (C) for calculating a work load corresponding to an amount of accelerator opening, a gear position and a vehicle speed drop in the work traveling, based on this vehicle speed characteristics for the load. Thereby, a proper correspondence operation is enabled to the load.

Description

  The present invention relates to a work vehicle that performs work travel by supplying engine power to a work system and a travel system.

As described in Patent Document 1, in a work vehicle that travels and works by supplying engine power to the work system and the travel system, a driving evaluation system is provided so that appropriate driving operations during work travel can be guided. Is known.
This operation evaluation system for work vehicles is based on the rotation characteristics corresponding to the engine load obtained as the amount of rotation drop from no-load rotation for engine rotation in the full load range for each accelerator opening, and the accelerator opening and engine rotation during work travel The engine load can be calculated from the drop amount. This driving evaluation system enables an appropriate driving operation by operations such as accelerator adjustment and shift position shift change.

JP 2011-144735 A

  However, the engine load includes not only the driving load acting on the drive wheels, but also the shift transmission unit and the work system load. There was a problem that evaluation was not obtained and trial and error were forced.

  An object of the present invention is to accurately adjust a traveling load in accordance with an operator's intention by an operation such as an accelerator adjustment or a shift change of a shift position in a work vehicle that travels by supplying engine power to a work system and a travel system. It is to provide a work vehicle that can be used.

According to the first aspect of the present invention, the main transmission unit is configured to supply engine rotational power to the traveling system (26) and the working system (40) according to the accelerator opening, and to change the shift position by the traveling system (26). (16, 17) In the work vehicle that supplies power to the drive wheel (3) via (16, 17) and travels while receiving a travel load on the drive wheel (3),
A load-adaptive vehicle speed characteristic obtained as a vehicle speed drop amount from no load by traveling over the full load range under each condition of the accelerator opening and the shift position is provided, and based on this load-compatible vehicle speed characteristic, A work travel evaluation system (C) for calculating a work load amount corresponding to the accelerator opening, the shift position, and the vehicle speed drop amount at the time is provided.

  According to a second aspect of the present invention, in the first aspect of the invention, the work travel evaluation system (C) is provided with a display section according to the degree of the work load, and a predetermined mark (S ) Is displayed.

  According to a third aspect of the present invention, in the invention according to the first or second aspect, the work travel evaluation system (C) is an engine corresponding to a load obtained corresponding to the vehicle speed characteristic corresponding to the load. Based on the fuel consumption amount, a fuel consumption amount corresponding to the vehicle speed drop amount obtained from the accelerator opening, the shift position, and the traveling vehicle speed in the work travel is calculated.

  According to the first aspect of the invention, the work load calculation device (C) is a vehicle speed corresponding to a load obtained as a vehicle speed drop amount from no load for traveling over the full load range under each condition of the accelerator opening and the shift position. Because it is possible to capture the work load during work travel according to the substance corresponding to the accelerator opening, shift position and vehicle speed drop amount during work travel based on the vehicle speed characteristics corresponding to this load Further, by adjusting the accelerator and shifting the shift position, it is possible to adjust the work load according to options such as work efficiency, and to perform an appropriate response operation according to the intention.

  According to the invention of claim 2, in addition to the effect of claim 1, the work load calculation device (C) displays the mark (S) with the display category according to the degree of work load as the lighting condition, so there is room for improvement. You can know the presence or absence.

  According to the invention of claim 3, in addition to the effect of claim 1 or claim 2, the fuel consumption during the work travel can be obtained by the work load calculation device (C), so that the accelerator adjustment and the shift position can be obtained. By changing the shift, etc., it is possible to adjust the travel according to the choices for improving the fuel consumption.

Overall side view of the leveling work vehicle of this embodiment Transmission system development diagram Display panel sketch Control system block diagram Characteristic relationship diagram regarding load level Symbol mark lighting control flowchart System display screen example Characteristic relationship diagram for fuel consumption Flow chart of fuel consumption display control Flowchart of other display control example 1 Flowchart of other display control example 2 Flowchart of other display control example 3 Flowchart of other display control example 4 Flowchart of other display control example 5 Flowchart of other display control example 6

Embodiments specifically configured based on the above technical idea will be described below with reference to the drawings.
The present invention enables work traveling with a load kept within an appropriate range by a work traveling evaluation system that grasps a work load based on the traveling vehicle speed of the work vehicle.

  The work travel evaluation system will be described with reference to an application example. As shown in FIG. 1, the work vehicle 1 to be applied is connected to the left and right steering front wheels 2 and 2 and the left and right steering front wheels 2 and 2 via the transmission 5. The rear wheels 3 and 3 are driven so that they can be switched by 2WD / 4WD, and the work machine W can be driven from the PTO shaft 40 at the rear of the machine body. It is built inside.

(Transmission system)
FIG. 2 is a transmission diagram of the transmission mechanism 13 in the transmission case 12 of the transmission 5. The transmission 5 includes a transmission case 12 and a transmission mechanism 13 that is disposed in the transmission case 12 and transmits rotational power from the engine 4 to the rear wheels 3 and the like. The transmission mechanism 13 transmits the rotational power from the engine 4 to the front wheels 2, the rear wheels 3, and the work equipment attached to the machine body, and drives them with the rotational power from the engine 4.

  Specifically, the transmission mechanism 13 includes an input shaft 14, a forward / reverse switching mechanism 15, a Hi-Lo transmission mechanism 16, a main transmission mechanism 17, an auxiliary transmission mechanism 18, a 2WD / 4WD switching mechanism 19, and a PTO. (Power take-off) It is comprised including the drive mechanism 20 grade | etc.,.

  The traveling system of the transmission mechanism 13 receives the rotational power generated by the engine 4 through the input shaft 14, the forward / reverse switching mechanism 15, the Hi-Lo transmission mechanism 16, the main transmission mechanism 17, and the auxiliary transmission mechanism 18 in this order. Can be communicated to. In addition, the transmission mechanism 13 transmits the rotational power generated by the engine 4 to the input shaft 14, the forward / reverse switching mechanism 15, the Hi-Lo transmission mechanism 16, the main transmission mechanism 17, the auxiliary transmission mechanism 18, and the 2WD / 4WD switching mechanism 19. It can be transmitted to the front wheel 2 via the order. Further, the transmission mechanism 13 can transmit the rotational power generated by the engine 4 to the work machine via the input shaft 14 and the PTO drive mechanism 20 in this order. The input shaft 14 is coupled to the output shaft of the engine 4, and the rotational power from the engine 4 is transmitted (input).

(Forward / reverse switching)
The forward / reverse switching mechanism 15 can switch the rotational power transmitted from the engine 4 to forward rotation or backward rotation. The forward / reverse switching mechanism 15 includes a forward gear 15a, a reverse gear 15b, a reverse gear 15c, a hydraulic multi-plate clutch (forward clutch) C1, and a hydraulic multi-plate clutch (reverse clutch) C2.

  The hydraulic multi-plate clutches C1 and C2 can switch the power transmission path in the forward / reverse switching mechanism 15 by switching the engaged / released state. The forward / reverse switching mechanism 15 transmits the rotational power transmitted to the input shaft 14 according to the engaged / released state of the hydraulic multi-plate clutches C1 and C2 to the counter shaft 21 by changing the transmission path. When the hydraulic multi-plate clutch C1 is in the engaged state and the hydraulic multi-plate clutch C2 is in the released state, the forward / reverse switching mechanism 15 transmits the rotational power transmitted to the input shaft 14 to the forward gear stage 15a, the hydraulic multi-plate. The torque is transmitted to the counter shaft 21 through the clutch C1 in the forward direction. When the hydraulic multi-plate clutch C1 is in the disengaged state and the hydraulic multi-plate clutch C2 is in the engaged state, the forward / reverse switching mechanism 15 transmits the rotational power transmitted to the input shaft 14 to the reverse gear 15b, the reverse gear 15c, The torque is transmitted to the counter shaft 21 through the hydraulic multi-plate clutch C2 in the reverse direction. Thereby, the forward / reverse switching mechanism 15 can switch the forward / backward movement of the tractor 1.

  The forward / reverse switching mechanism 15 also functions as a main clutch. When both the hydraulic multi-plate clutches C1 and C2 are released, a neutral state is established and power transmission to the front wheels 2 and rear wheels 3 is interrupted. be able to. The forward / reverse switching mechanism 15 can switch between forward, reverse, and neutral by hydraulic control when an operator operates a forward / reverse switching lever (not shown), for example. Further, both the hydraulic multi-plate clutches C1 and C2 can be released by depressing a clutch pedal (not shown).

(Hi-Lo)
The Hi-Lo speed change mechanism 16 can change the rotational power transmitted from the engine 4 at a high speed stage or a low speed stage. The Hi-Lo transmission mechanism 16 includes a Hi (high speed) side gear stage 16a, a Lo (low speed) side gear stage 16b, a hydraulic multi-plate clutch (Hi (high speed) side clutch) C3, and a hydraulic multi-plate clutch (Lo (low speed) side). Clutch) C4. The hydraulic multi-plate clutches C3 and C4 can switch the power transmission path in the Hi-Lo transmission mechanism 16 by switching the engaged / released state. The Hi-Lo transmission mechanism 16 transmits the rotational power transmitted to the counter shaft 21 to the transmission shaft 22 by changing the transmission path in accordance with the engaged / released state of the hydraulic multi-plate clutches C3 and C4. When the hydraulic multi-plate clutch C3 is in the engaged state and the hydraulic multi-plate clutch C4 is in the released state, the Hi-Lo transmission mechanism 16 transmits the rotational power transmitted to the counter shaft 21 to the hydraulic multi-plate clutch C3, Hi side. The speed is changed via the gear stage 16a and transmitted to the transmission shaft 22.

  The Hi-Lo transmission mechanism 16 transmits the rotational power transmitted to the counter shaft 21 to the hydraulic multi-plate clutch C4, Lo side when the hydraulic multi-plate clutch C3 is in the released state and the hydraulic multi-plate clutch C4 is in the engaged state. The speed is changed via the gear stage 16 b and transmitted to the transmission shaft 22. As a result, the Hi-Lo transmission mechanism 16 can change the rotational power from the engine 4 at the transmission ratio of the Hi side gear stage 16a or the transmission ratio of the Lo (low speed) side gear stage 16b and transmit it to the subsequent stage. it can. For example, the Hi-Lo transmission mechanism 16 can switch between the Hi (high speed) side and the Lo (low speed) side by hydraulic control by turning on / off the Hi-Lo changeover switch (high / low speed change operation switch) by an operator. The speed can be changed in one of two stages, high speed and low speed. Further, the Hi-Lo speed change mechanism 16 can change speed while the tractor 1 is traveling due to the above-described configuration.

(Main transmission)
The main speed change mechanism 17 can change the rotational power transmitted from the engine 4 at any one of a plurality of shift speeds. The main speed change mechanism 17 is a synchromesh type speed change mechanism, and here, the rotational power transmitted from the engine 4 via the forward / reverse switching mechanism 15 and the Hi-Lo speed change mechanism 16 can be changed. The main speed change mechanism 17 includes a first speed gear stage 17a, a second speed gear stage 17b, a third speed gear stage 17c, a fourth speed gear stage 17d, a fifth speed gear stage 17e, and a sixth speed gear as a plurality of speed stages. A stage 17f is included. The main transmission mechanism 17 transmits the rotational power transmitted to the transmission shaft 22 according to the coupling state of the first speed gear stage 17a to the sixth speed gear stage 17f with the transmission shaft 22 from the first speed gear stage 17a to the first speed gear stage 17a. The speed is changed via one of the sixth speed gears 17f and transmitted to the transmission shaft 23.

  Thus, the main transmission mechanism 17 can shift the rotational power from the engine 4 at any gear ratio of the first speed gear stage 17a to the sixth speed gear stage 17f and transmit it to the subsequent stage. For example, the main transmission mechanism 17 can select and switch one of a plurality of shift stages by operating a main shift operation lever (not shown) by an operator. The speed can be changed at any one of the six speeds of the sixth speed gear stage 17f. Further, the main transmission mechanism 17 can change gears while the tractor 1 is traveling due to the above-described configuration.

  The auxiliary transmission mechanism 18 can change the rotational power transmitted from the engine 4 through the forward / reverse switching mechanism 15, the Hi-Lo transmission mechanism 16, and the main transmission mechanism 17 in order. The sub-transmission mechanism 18 includes a first sub-transmission 24, a second sub-transmission 25, and the like, and the rotational power transmitted to the transmission shaft 23 is transmitted to the first sub-transmission 24 and the second sub-transmission 25. And the like, and then transmitted to the transmission shaft 26. The first sub-transmission 24 can transmit the rotational power transmitted from the engine 4 and shifted by the main transmission mechanism 17 or the like at the high speed stage or the low speed stage and transmit it to the rear wheel 3 side that is the driving wheel. The second sub-transmission 25 shifts the rotational power transmitted from the engine 4 and shifted by the main transmission mechanism 17 or the like at an extremely low speed that is lower than that of the first sub-transmission 24, and is a rear wheel 3 that is a driving wheel. Can be transmitted to the side.

  The first sub transmission 24 of the sub transmission mechanism 18 includes a first gear 24a, a second gear 24b, a third gear 24c, a fourth gear 24d, and a shifter 24e. The first gear 24a is coupled to the transmission shaft 23 so as to be integrally rotatable, and rotational power from the transmission shaft 23 is transmitted (input). The second gear 24b meshes with the first gear 24a. The third gear 24c is coupled to the second gear 24b so as to be integrally rotatable. The fourth gear 24d meshes with the third gear 24c. The shifter 24e switches the coupling state of the first gear 24a, the fourth gear 24d, and the transmission shaft 26. The shifter 24e has a Hi (high speed) side position where the first gear 24a and the transmission shaft 26 are coupled so as to be integrally rotatable, a Lo (low speed) side position where the fourth gear 24d and the transmission shaft 26 are coupled so as to be integrally rotatable, Neither the first gear 24a nor the fourth gear 24d is coupled to the transmission shaft 26 and can move to the neutral position (neutral position) to be released. The first sub-transmission 24 transmits the rotational power transmitted to the transmission shaft 23 to the transmission shaft 26 by switching the transmission path according to the position of the shifter 24e. When the shifter 24e is in the Hi side position, the first auxiliary transmission 24 transmits the rotational power transmitted to the transmission shaft 23 from the first gear 24a to the second gear 24b, the third gear 24c, and the fourth gear 24d. The transmission is transmitted to the transmission shaft 26 without being interposed (transmission is performed from the transmission shaft 23 → the first gear 24a → the transmission shaft 26). When the shifter 24e is in the Lo side position, the first auxiliary transmission 24 transmits the rotational power transmitted to the transmission shaft 23 from the first gear 24a to the second gear 24b, the third gear 24c, the fourth gear 24d, and the shifter. The speed is sequentially reduced via 24e and transmitted to the transmission shaft 26.

  As a result, the first auxiliary transmission 24 transmits the rotational power from the engine 4 to the Hi (high speed) side gear ratio without passing through the second gear 24b, the third gear 24c, and the fourth gear 24d, or the second gear. 24b, the third gear 24c, and the fourth gear 24d can be shifted at the Lo (low speed) side gear ratio and transmitted to the subsequent stage. Further, when the shifter 24e is in the neutral position, the first auxiliary transmission 24 is in a state where both the first gear 24a and the fourth gear 24d are idle with respect to the transmission shaft 26, that is, in a neutral state. For example, the first sub-transmission 24 is operated by an operator operating a first sub-transmission operation lever (not shown), so that the position of the shifter 24e is switched to the Hi (high speed) side, the Lo (low speed) side, You can switch neutral.

  The second subtransmission 25 of the subtransmission mechanism 18 includes a first gear 25a, a second gear 25b, a third gear 25c, a fourth gear 25d, and a shifter 25e. The first gear 25a is coupled to the fourth gear 24d so as to be integrally rotatable. The second gear 25b meshes with the first gear 25a. The third gear 25c is coupled to the second gear 25b so as to be integrally rotatable. The fourth gear 25d meshes with the third gear 25c. The shifter 25e switches the coupling state between the fourth gear 25d and the transmission shaft 26. The shifter 25e has a pole Lo (very low speed) side position where the fourth gear 25d and the transmission shaft 26 are coupled so as to be integrally rotatable, and a neutral position (neutral position) where the fourth gear 25d and the transmission shaft 26 are not coupled and released. Position). The second sub-transmission 25 transmits the rotational power transmitted to the transmission shaft 23 to the transmission shaft 26 by switching the transmission path according to the position of the shifter 25e. When the first sub-transmission 24 is in the neutral state and the shifter 25e is in the pole Lo side position, the second sub-transmission 25 uses the rotational power transmitted to the transmission shaft 23 as the first sub-transmission 24. From the first gear 24a, the second gear 24b, the third gear 24c, the fourth gear 24d, the first gear 25a, the second gear 25b, the third gear 25c, the fourth gear 25d, and the shifter 25e of the second auxiliary transmission 25 are connected. Are sequentially decelerated through and transmitted to the transmission shaft 26.

  As a result, the second auxiliary transmission 25 converts the rotational power from the engine 4 into the second gear 24b, the third gear 24c, the fourth gear 24d, the first gear 25a, the second gear 25b, the third gear 25c, The speed can be changed at a speed ratio on the pole Lo (very low speed) side via the 4 gear 25d and transmitted to the subsequent stage. Further, when the shifter 25e is in the neutral position, the second auxiliary transmission 25 is in a state where the fourth gear 25d is idling with respect to the transmission shaft 26, that is, in a neutral state. The second sub-transmission 25 is in a neutral state when the first sub-transmission 24 is on the Hi (high speed) side or the Lo (low speed) side. The second sub-transmission 25 switches the position of the shifter 25e to switch between the pole Lo (very low speed) side and the neutral, for example, when a second sub-shift operation lever (not shown) is operated by an operator. Can do.

  Therefore, the subtransmission mechanism 18 combines the rotational power transmitted to the transmission shaft 23 with the first subtransmission 24 and the second subtransmission 25, so that one of the three stages of high speed, low speed, and extremely low speed can be obtained. Either can be changed and transmitted to the transmission shaft 26. That is, the subtransmission mechanism 18 can shift at the Hi (high speed) stage when the first subtransmission 24 is in the Hi (high speed) side and the second subtransmission 25 is in the neutral state. . The subtransmission mechanism 18 can shift at the Lo (low speed) stage when the first subtransmission 24 is in the Lo (low speed) side and the second subtransmission 25 is in the neutral state. When the first sub-transmission 24 is in the neutral state and the second sub-transmission 25 is on the pole Lo (very low speed) side, the sub-transmission mechanism 18 shifts at the pole Lo (very low speed) stage. Can do. The auxiliary transmission mechanism 18 is switched between high speed, low speed, and extremely low speed while the tractor 1 is stopped.

  The transmission mechanism 13 of the transmission 5 transmits the rotational power transmitted to the transmission shaft 26 to the rear wheel 3 via the rear wheel differential 27, the axle (drive shaft) 28, the planetary gear mechanism 29, and the like. As a result, in the tractor 1, the rear wheel 3 is rotationally driven as a drive wheel by the rotational power from the engine 4.

  To summarize the above description, the rotation of the input shaft 14 is first switched to forward rotation or reverse rotation by the forward / reverse switching mechanism 15, and is shifted by the Hi-Lo transmission mechanism 16 in one of two stages of high speed and low speed. The main transmission mechanism 17 is shifted at any one of the six speeds of the first speed gear stage 17a to the sixth speed gear stage 17f, and the auxiliary transmission mechanism 18 is selected from any of the three speeds of high speed, low speed, and extremely low speed. And is transmitted to the axle 28. In other words, the rotation of the input shaft 14 is shifted by any one of 2 × 6 × 3 = 36 stages by the transmission mechanism 13 of the transmission 5 and transmitted to the axle 28.

(2WD / 4WD)
The 2WD / 4WD switching mechanism 19 switches whether or not the rotational power transmitted to the transmission shaft 26 is transmitted to the front wheel 2 side. The 2WD / 4WD switching mechanism 19 includes a transmission shaft 19a, a first gear 19b, a second gear 19c, a transmission shaft 19d, and a shifter 19e. The transmission shaft 19a transmits (inputs) the rotational power from the transmission shaft 26 via the gear 30, the gear 31, the transmission shaft 32, the coupling 33, and the like. The transmission gear 19a is inserted into the first gear 19b, and the first gear 19b is assembled so as to be rotatable relative to the transmission shaft 19a. The second gear 19c meshes with the first gear 19b. The transmission shaft 19d is coupled to the second gear 19c so as to be rotatable together. The shifter 19e switches the coupling state between the transmission shaft 19a and the first gear 19b. The shifter 19e is movable to a 4WD position where the transmission shaft 19a and the first gear 19b are coupled so as to be integrally rotatable, and to a 2WD position (neutral position) where the transmission shaft 19a and the first gear 19b are not coupled and released. is there. When the shifter 19e is at the 4WD position, the 2WD / 4WD switching mechanism 19 transmits the rotational power transmitted to the transmission shaft 19a to the transmission shaft 19d via the first gear 19b and the second gear 19c.

  Thereby, the 2WD / 4WD switching mechanism 19 can transmit the rotational power from the engine 4 to the front wheel 2 side. The transmission mechanism 13 of the transmission 5 transmits the rotational power transmitted to the transmission shaft 19d to the front wheels 2 via the front wheel differential 34, the axle (drive shaft) 35, the vertical shaft 36, the planetary gear mechanism 37, and the like. As a result, the tractor 1 can be driven by four-wheel drive, with the front wheels 2 and the rear wheels 3 being rotationally driven as drive wheels by the rotational power from the engine 4. In the 2WD / 4WD switching mechanism 19, when the shifter 19e is in the 2WD position, the transmission of the rotational power transmitted to the transmission shaft 19a to the transmission shaft 19d side is cut off. As a result, the tractor 1 can travel by two-wheel drive. The 2WD / 4WD switching mechanism 19 can switch between two-wheel drive and four-wheel drive by switching the position of the shifter 19e, for example, when a 2WD / 4WD switch lever (not shown) is operated by an operator.

(PTO)
The PTO drive mechanism 20 drives the work machine with the power from the engine 4 by shifting the rotational power transmitted from the engine 4 and outputting it from the PTO shaft 40 at the rear of the machine body to the work machine. The PTO drive mechanism 20 includes a PTO clutch mechanism 38, a PTO transmission mechanism 39, a PTO shaft 40, and the like.

  The PTO clutch mechanism 38 switches between transmission and interruption of power to the PTO shaft 40 side. The PTO clutch mechanism 38 includes a gear 38a, a hydraulic multi-plate clutch C5, and a transmission shaft 38b. The gear 38a meshes with a gear 41 that is coupled to the input shaft 14 so as to be integrally rotatable. The hydraulic multi-plate clutch C5 switches the power transmission state between the gear 38a and the transmission shaft 38b by switching the engaged / released state. The PTO clutch mechanism 38 enters a PTO drive state in which power is transmitted to the PTO shaft 40 side when the hydraulic multi-plate clutch C5 is engaged, and the rotational power transmitted from the input shaft 14 to the gear 38a via the gear 41. Is transmitted to the transmission shaft 38b via the hydraulic multi-plate clutch C5. When the hydraulic multi-plate clutch C5 is released, the PTO clutch mechanism 38 is in a PTO non-driven state (neutral state) in which transmission of power to the PTO shaft 40 side is interrupted, and the rotational power transmitted to the gear 38a is reduced. Transmission to the transmission shaft 38b side is interrupted. The PTO clutch mechanism 38 can switch between a PTO driving state and a PTO non-driving state by hydraulic control, for example, when an operator turns on / off a PTO switching switch (not shown). The tractor 1 is provided with a gear pump 70 through a gear 70a meshing with the gear 38a, a gear 70b meshing with the gear 70a, and the like. The gear pump 70 applies hydraulic pressure to a hydraulic system such as the transmission mechanism 13.

  The PTO speed change mechanism 39 changes speed when power is transmitted to the PTO shaft 40 side. The PTO speed change mechanism 39 includes a Hi (high speed) side gear stage 39a, a Lo (low speed) side gear stage 39b, a transmission shaft 39c, and a shifter 39d. The PTO transmission mechanism 39 changes the rotational power transmitted to the transmission shaft 38b via the Hi side gear stage 39a or the Lo side gear stage 39b according to the position of the shifter 39d, and transmits it to the transmission shaft 39c. To do. The shifter 39d switches the coupling state of the Hi side gear stage 39a, the Lo side gear stage 39b, and the transmission shaft 39c. The shifter 39d has a Hi (high speed) side position for coupling the Hi side gear stage 39a and the transmission shaft 39c, a Lo (low speed) side position for coupling the Lo side gear stage 39b and the transmission shaft 39c, a Hi side gear stage 39a, None of the Lo-side gear stage 39b is coupled to the transmission shaft 39c and can be moved to the neutral position (neutral position) to be released. When the shifter 39d is at the Hi side position, the PTO transmission mechanism 39 transmits the rotational power transmitted to the transmission shaft 38b to the transmission shaft 39c via the Hi side gear stage 39a. When the shifter 39d is in the Lo side position, the PTO transmission mechanism 39 transmits the rotational power transmitted to the transmission shaft 38b to the transmission shaft 39c via the Lo side gear stage 39b.

  As a result, the PTO transmission mechanism 39 can shift the rotational power from the engine 4 at the gear ratio of the Hi-side gear stage 39a or the gear ratio of the Lo-side gear stage 39b and transmit it to the subsequent stage. Further, when the shifter 39d is in the neutral position, the PTO transmission mechanism 39 is in a state where both the Hi side gear stage 39a and the Lo side gear stage 39b are idle with respect to the transmission shaft 39c, that is, in a neutral state. The PTO speed change mechanism 39 can switch the position of the shifter 39d and switch between the Hi (high speed) side, the Lo (low speed) side, and the neutral, for example, when an operator operates a PTO speed change operation lever described later. The speed can be changed in one of two stages, high speed and low speed.

  The PTO shaft 40 is coupled to a work machine and transmits rotational power from the engine 4 to the work machine. The PTO shaft 40 is rotationally driven by the rotational power transmitted to the transmission shaft 39c being transmitted through the first gear 41, the second gear 42, and the like.

  In summary, the rotation of the input shaft 14 is transmitted to the PTO speed change mechanism 39 via the PTO clutch mechanism 38, and the PTO speed change mechanism 39 changes the speed in one of two stages of high speed and low speed. , Transmitted to the PTO shaft 40, and the PTO shaft 40 is rotationally driven. As a result, the tractor 1 can change the rotational power transmitted from the engine 4 and output it from the PTO shaft 40 to the work implement, thereby driving the work implement.

(Operation control section)
In the tractor 1, various operation levers (not shown) are arranged in the cabin 9 or in the rear part 1R of the machine body. In the cabin 9, the tractor 1 is provided with a forward / reverse switching lever, a Hi-Lo switching switch, a main transmission operation lever, a 2WD / 4WD switching lever, and a PTO switching switch. Further, the tractor 1 is provided with a PTO speed change operation lever (not shown) at the rear part 1R of the airframe. The forward / reverse switching lever performs the forward / reverse switching operation of the forward / reverse switching mechanism 15, and the operator operates the forward / reverse switching lever to switch the forward / reverse switching mechanism 15 to forward, reverse, or neutral. Can do. The Hi-Lo change-over switch is for performing a Hi-Lo change-over operation (high / low-speed change operation) of the Hi-Lo change-over mechanism 16, and an operator operates the Hi-Lo change-over switch so that the Hi-Lo change-over mechanism is operated. 16 can be switched between high speed and low speed. The main speed change operation lever is used to perform the main speed change operation of the main speed change mechanism 17, and when the operator operates the main speed change operation lever, the main speed change mechanism 17 is changed from the first speed gear stage 17a to the sixth speed gear. It is possible to switch to any one of the six stages 17f or to neutral. The 2WD / 4WD switching lever is for performing the 2WD / 4WD switching operation of the 2WD / 4WD switching mechanism 19, and when the operator operates the 2WD / 4WD switching lever, the 2WD / 4WD switching mechanism 19 is driven by two wheels. It can be switched to four-wheel drive. The PTO change-over switch performs clutch change-over operation of the PTO clutch mechanism 38, and the operator can switch the PTO clutch mechanism 38 between the PTO drive state and the PTO non-drive state by operating the PTO change-over switch. . The PTO speed change operation lever performs a PTO speed change operation of the PTO speed change mechanism 39, and the operator can switch the PTO speed change mechanism 39 to high speed, low speed, and neutral by operating the PTO speed change operation lever.

  The tractor 1 according to the present embodiment includes a first sub-transmission operation lever that performs the first sub-transmission operation of the first sub-transmission 24 of the sub-transmission mechanism 18 and the second sub-transmission 25 of the second sub-transmission mechanism 18. The second sub-shift operation lever that performs the two-sub shift operation is provided separately, thereby improving versatility. Both the first auxiliary transmission operation lever and the second auxiliary transmission operation lever are provided in the cabin 9. The tractor 1 according to the present embodiment adds a gear position (for example, an extremely low speed gear) by adding a second sub-transmission 25 to the first sub-transmission 24 in a retrofit manner in the sub-transmission mechanism 18, for example. A second sub-transmission operation lever that is configured to be capable of operating a shift speed by adding the second sub-transmission 25 is provided separately from the first sub-transmission operation lever.

  The work vehicle 1 adjusts the output of the engine 4 by an accelerator pedal disposed in the cabin 9, and a combination of the Hi-Lo transmission mechanism 16 and the main transmission mechanism 17 of the main transmission unit by a shift operation of the transmission lever. The gear ratio can be selected to adjust the vehicle speed. Further, the meter panel 51 in the cabin 9 is provided with a display unit 52 such as a liquid crystal monitor as shown in FIG. 3 as an example of the sketch, and the work travel evaluation system displays the load, fuel consumption, etc. in the work travel. And display necessary operation guidance. By adjusting the accelerator pedal and the main shift shift position in accordance with the display on the display unit 52, work traveling corresponding to the work load becomes possible.

(Work travel evaluation)
As shown in FIG. 4, the block diagram of the work travel evaluation system is arranged on an operation panel such as a meter panel 51, and an accelerator sensor 4a that inputs an operation status in addition to a navigation switch 53 that selects application of the system. And the shift position sensor 17s, the engine rotation sensor 4r for inputting the driving situation, and the vehicle speed sensor 1s as input conditions, the control unit C, which is a work load calculation device, calculates the load degree and the fuel consumption, and the display unit 52 Display control including display of appropriate evaluation marks.

  The memory of the control unit C stores a load map including a relationship between a theoretical vehicle speed that is a no-load vehicle speed provided in advance for each shift position and a vehicle speed drop amount. The load map is a traveling vehicle speed characteristic due to the driving wheel load obtained by measuring the traveling vehicle speed ranging from no load to the full load range at the accelerator opening at each shift position, and based on the load traveling map, The work travel load amount can be calculated as the vehicle speed drop amount from the no-load vehicle speed.

(Load degree)
Specifically, as shown in a theoretical vehicle speed relationship diagram of FIG. 5A showing a characteristic relationship diagram regarding the degree of load, a theory that is determined as an unloaded vehicle speed corresponding to the accelerator opening (Ao) at each shift position by the engine output characteristics. Based on the relationship (Ts = Ao) with the vehicle speed (Ts), the theoretical vehicle speed is calculated from the accelerator opening in the entire range for each shift position.

  Next, as shown in the vehicle speed relationship diagram of FIG. 5B, the theoretical vehicle speed (Ts) and the vehicle speed (S) are in a correlation (S = Ts), and have different characteristics for each shift position. When the aircraft is not loaded (no load condition), the vehicle speed of S1 is obtained with respect to the set theoretical vehicle speed (Ts1). When a load is applied to the airframe, the vehicle speed decreases to S2 or S3 with respect to the vehicle speed S1. A difference occurs between the vehicle speeds S1 and Sn, and this difference is the vehicle speed drop amount (Sd). Therefore, the vehicle speed drop amount (Sd) can be obtained by comparing the theoretical vehicle speed (S1) and the vehicle speed (Sn) (Sd = S1-Sn).

  Next, as shown in the load degree relationship diagram of FIG. 5 (c), when the drop amount is large due to the relationship between the vehicle speed drop amount (Sd) and the load degree (L) to the fuselage (L = Sd), the load degree Also grows. Further, as shown in the vehicle speed drop amount relationship diagram of FIG. 5D, the current vehicle speed is stored in advance in the ECU for each shift position based on the relationship between the theoretical vehicle speed (accelerator opening), the vehicle speed drop amount, and the load degree. The load degree can be detected (the curve shows the contour line (boundary value) of the load degree). In the example of the figure, when the theoretical vehicle speed is “Ts1” and the vehicle speed drop amount is “Sd1”, the intersection of Ts1 and Sd1 indicates the load degree. In this case, it is possible to obtain the degree of load = about 70%. When the theoretical vehicle speed is “Ts1” and the vehicle speed drop amount is “Sd2”, it is possible to obtain the degree of load = about 38%. When the theoretical vehicle speed changes to “Ts2” and the vehicle speed drop amount is “Sd3”, the load degree = about 35% can be obtained.

The CPU of the control unit C calculates the vehicle speed drop amount from the theoretical vehicle speed, which is a no-load compatible vehicle speed, and calculates the degree of load from the vehicle speed drop amount and each input value.
Similarly, the load degree evaluation unit in the control unit C performs an evaluation system for the lighting control of the green mark, which is the symbol mark S representing the evaluation for improvement on the liquid crystal monitor, by operating the navigation switch as shown in the flowchart of FIG. When the corresponding determination is made in the first processing step (hereinafter abbreviated as “S1”), the navigation indicating the start of application as shown in the system standard screen example of FIG. After the standard screen is displayed (S1a), a green mark is lit in the symbol mark field S when the following lighting conditions are satisfied, and a message for operation guidance (operation guide) is displayed by the subsequent display operation.

  For lighting conditions, there is room for improvement evaluation according to vehicle speed, engine speed, and load level. Specifically, when the vehicle speed is 0.5 km / h or more (S2) and the engine speed is 2300 min-1 or more (S3), sensor input The CPU calculates the degree of load according to (S3a, S3b), and when the condition (S4) where the degree of load is less than 60% is satisfied, the green mark is turned on in the symbol mark column S of the liquid crystal monitor 52 (S4a). The green mark in the symbol mark column S indicates a state in which the accelerator opening degree can be tightened to suppress the engine rotation and the vehicle speed can be increased by one step, thereby enabling efficient work traveling with an appropriate load. Contributes to energy-saving operation and improves workability.

  If the navigation switch operation (S5) is further performed after the switch operation, as shown in the screen example of the room for improvement evaluation classification in FIG. 7 (b) when the above condition is satisfied by re-determination (S6) of the above condition. In addition, a specific guidance message such as “lowering the engine speed will improve fuel efficiency” is displayed in the message field M (S6a), and if the condition is not satisfied, the symbol mark of the “navigation standard screen” above The display in the column S is turned off, or an appropriate evaluation message such as “Appropriate operation is possible” is displayed in the message column M (S6b). In addition, by operating the navigation switch following the display when the condition is satisfied, other options can be specifically guided by displaying another guidance message such as "Raising the gearshift position one step improves fuel efficiency". Can do.

(Fuel consumption)
Next, evaluation of fuel consumption will be described.
The memory of the control unit C stores a fuel consumption map including a relationship between a theoretical vehicle speed and a vehicle speed drop amount provided in advance for each shift position. The fuel consumption map is a fuel consumption characteristic by the load of the driving wheel obtained by measuring the traveling vehicle speed ranging from no load to the full load range at the accelerator opening at each shift position, and work based on this fuel consumption map Based on the traveling vehicle speed, the fuel consumption amount can be calculated in correspondence with the vehicle speed drop amount from the no-load vehicle speed.

  Specifically, as shown in the theoretical vehicle speed relationship diagram of FIG. 8 (a) showing the characteristic relationship diagram regarding fuel consumption and the vehicle speed relationship diagram of FIG. 8 (b), the theoretical vehicle speed relationship of FIG. Similarly to the vehicle speed relationship diagram of FIG. 5 and FIG. 5B, the vehicle speed drop amount (Sd) can be obtained by comparing the theoretical vehicle speed (S1) and the vehicle speed (Sn) (Sd = S1-Sn).

  Next, as shown in the fuel consumption relationship diagram of FIG. 8C, when the drop amount is large due to the relationship between the vehicle speed drop amount (Sd) and the fuel consumption amount (Fc) (Fc = Sd), the fuel consumption amount Also grows. Further, as shown in the vehicle speed drop amount relationship diagram of FIG. 8D, by storing in advance in the ECU for each shift position according to the relationship between the theoretical vehicle speed (accelerator opening), the vehicle speed drop amount, and the fuel consumption amount, The current fuel consumption can be detected (the curve shows fuel consumption contours (boundary values)). In the example of the figure, when the theoretical vehicle speed is “Ts1” and the vehicle speed drop amount is “Sd1”, the intersection of Ts1 and Sd1 indicates the current fuel consumption. In this case, fuel consumption = about 7 L / Hr can be obtained. Further, when the theoretical vehicle speed is “Ts1” and the vehicle speed drop amount is “Sd2”, the fuel consumption amount = about 3.8 L / Hr can be obtained. When the theoretical vehicle speed changes to “Ts2” and the vehicle speed drop amount is “Sd3”, the fuel consumption amount is about 3.5 L / Hr.

The CPU of the control unit C calculates the vehicle speed drop amount from the theoretical vehicle speed that is a no-load compatible vehicle speed, calculates the fuel consumption amount from the vehicle speed drop amount and each input value, and calculates the fuel consumption from the fuel consumption amount and the current vehicle speed. (Distance fuel consumption) is calculated.
As for the display control of the fuel consumption (distance fuel consumption) on the liquid crystal monitor, as shown in the flowchart of FIG. 9, the accelerator opening, the vehicle speed, the shift position, and the engine speed by the sensor reading process (S11a to S11d) are navigated. When the switch is operated (S12), when the vehicle speed is 0.5 km / h or more (S13) and the engine speed is 1500 min-1 or more (S14), the fuel consumption calculated by the CPU (distance fuel consumption = vehicle speed / fuel consumption) is As shown in FIG. 7A, it is displayed in the fuel consumption column F.
In addition, by a subsequent navigation switch operation, a part of the message field M can be displayed as the fuel efficiency field F so that it can be recognized again.

(Display conditions)
In the display control by the travel evaluation system, as shown in the flowchart of another display control example 1 in FIG. 10, the detected value of the accelerator sensor is equal to or greater than a certain value (S21), and the PTO rotation sensor is detected. In the case (S22), by providing a control process for calculating the engine load factor and displaying the result (S23), it is possible to avoid insufficient accuracy in the low rotation range and to perform an appropriate work instruction based on the high accuracy result. Become.

  As shown in the flowchart of another display control example 2 in FIG. 11, when the detected value of the engine rotation sensor is equal to or greater than a certain value (S31) and the PTO rotation sensor is detected (S32), the engine load By providing a control process for calculating the rate and displaying the result (S33), it is possible to avoid an insufficient accuracy in the low rotation region as described above, and to perform an appropriate work instruction based on the high-precision result.

  As shown in the flowchart of another display control example 3 in FIG. 12, when the detected value of the engine rotation sensor is not less than a certain value (S41) and the forward or reverse solenoid output is ON (S42), the engine By providing a control process for calculating the load factor and displaying the result (S43), it is possible to avoid an insufficient accuracy in the low rotation region as described above, and to perform an appropriate work instruction based on a highly accurate result.

  Further, as shown in the flowchart of another display control example 4 in FIG. 13, when the detected value of the engine rotation sensor is equal to or greater than a predetermined value (S 51) and the detected vehicle speed is equal to or greater than a predetermined value (S 52) By providing a control process for calculating the load factor and displaying the result (S53), it is possible to avoid an insufficient accuracy in the low rotation region as described above, and to perform an appropriate work instruction based on a highly accurate result.

  As shown in the flowchart of another display control example 5 in FIG. 14, the engine load factor is calculated when the detected value of the engine rotation sensor is not less than a certain value (S61) and the PTO solenoid is ON (S62). By providing a control process for displaying the result (S63), it is possible to avoid an insufficient accuracy in the low rotation region as described above, and to perform an appropriate work instruction based on a highly accurate result.

  Further, as shown in the flowchart of another display control example 6 in FIG. 15, the detected value of the engine rotation sensor is equal to or greater than a certain value (S71), and all the operation operation lever relations (travel system, work system) are operated. By providing a control process for calculating the engine load factor and displaying the result (S74) from the end of clutch control in the state (S72) (S73), it is possible to avoid a lack of accuracy in the low rotation range as described above and to achieve high accuracy. Therefore, it is possible to give an appropriate work instruction based on the result.

DESCRIPTION OF SYMBOLS 1 Work vehicle 3 Drive wheel 16, 17 Main transmission part 26 Travel system 40 Work system 52 Display part C Work travel evaluation system S mark (improvement room display)

Claims (3)

The engine rotational power is supplied to the traveling system (26) and the working system (40) according to the accelerator opening, and the main transmission unit (16, 17) is capable of shifting the shift position by the traveling system (26). In a work vehicle that transmits power to the drive wheel (3) and travels while receiving a travel load on the drive wheel (3),
A load-adaptive vehicle speed characteristic obtained as a vehicle speed drop amount from no load by traveling over the full load range under each condition of the accelerator opening and the shift position is provided, and based on this load-compatible vehicle speed characteristic, A work vehicle is provided with a work travel evaluation system (C) for calculating a work load amount corresponding to an accelerator opening, a shift position, and a vehicle speed drop amount.   2. The work vehicle according to claim 1, wherein the work travel evaluation system (C) includes a display section according to a degree of the work load, and displays a predetermined mark (S) using the display section as a lighting condition. .   The work travel evaluation system (C) uses the vehicle speed drop obtained from the accelerator opening, the shift position, and the travel vehicle speed in the work travel based on the engine fuel consumption corresponding to the load obtained corresponding to the vehicle speed characteristic corresponding to the load. The work vehicle according to claim 1, wherein a fuel consumption amount corresponding to the amount is calculated.

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