JP2006070983A - Working vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a working vehicle capable of appropriately performing working by displaying the present number of shift stages, besides engine speed and traveling speed of a car body. <P>SOLUTION: An engine speed sensor 66 for detecting engine speed, a car speed sensor 67 for detecting rotating speed of an output part of a multi-stage transmission and a PTO rotating speed sensor 68 are connected to an input side of a control unit 65, and a display unit 77 is connected to an output side thereof, and a table for housing gear ratio of each of shift stages of the multi-stage transmission is set inside the control unit 65. A shift stage in the multi-stage transmission is computed on the basis of outputs of the engine speed sensor 66 and the car speed sensor 67 and the gear ratio of the table, and displayed in the display unit 77, and an operator can thereby easily recognize the shift stage and can perform appropriate working. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a work vehicle in which a work machine is connected to a rear portion of a vehicle body provided with a drive source, and the vehicle body and the work machine are driven by the drive source.

  2. Description of the Related Art A working vehicle that includes an engine and has a working machine such as a cultivator connected to a rear portion of a vehicle body (for example, a tractor) that is driven by the engine is known. In the work vehicle, the engine is driven to travel by the engine, and the work machine is driven through the PTO shaft to perform a required work.

  When plowing a farm field with the working vehicle, if the rotation speed of the tilling claw is constant, the faster the working vehicle, the rougher the soil after plowing, and the slower the working vehicle, the finer the work. If the traveling speed of the vehicle is constant, the soil block after tillage becomes finer as the rotation speed of the tillage claw increases, and becomes coarser as the rotation speed of the tillage claw decreases. In addition, when the traveling speed of the work vehicle decreases, the work efficiency decreases. Therefore, it is necessary to work while confirming the work conditions such as the traveling speed of the work vehicle and the rotation speed of the tilling claws so that the work lump will have the required roughness without reducing the work efficiency. Become.

  As a conventional technique, an engine speed sensor that detects the engine speed, a clutch detection sensor that detects whether the PTO hydraulic clutch is on or off, and a shift position detection sensor that detects the shift position of the PTO transmission mechanism are provided. It is known that the number of rotations of the PTO shaft is obtained from the output signals of the detection sensor, the clutch detection sensor, and the shift position detection sensor by an arithmetic unit, and the number of rotations of the PTO shaft is displayed on a PTO rotation number indicating meter. (For example, refer to Patent Document 1).

  This prior art has an advantage that the driver can work while visually recognizing the rotational speed of the PTO shaft by arranging the PTO rotational speed indicating meter on the operation panel in front of the driver's seat.

JP-A-6-153610 (page 3, FIG. 1)

  In the above-described prior art, only the engine speed and the PTO shaft speed are displayed on the operation panel, and the traveling speed of the vehicle body driven via the multi-stage transmission (the rotation of the output section of the multi-stage transmission). Number) and the rotational speed of the PTO shaft are not taken into consideration at all, and appropriate work cannot be performed.

  In view of the above circumstances, an object of the present invention is to provide a working vehicle capable of performing appropriate work by displaying not only the traveling speed of the vehicle body but also the current traveling speed.

In order to achieve the above object, the present invention according to claim 1 is directed to a working vehicle that travels on a vehicle body by transmitting rotation from an engine (12) to drive wheels (16, 17) via a multi-stage transmission (40). In (10),
An engine speed sensor (66) for detecting the speed of the engine (12);
A vehicle speed sensor (67) for detecting the rotational speed of the output portion of the multi-stage transmission (40);
A table (85) for storing the gear ratio of each gear stage of the multi-stage transmission (40);
A control unit (65) for calculating the gear position of the multi-stage transmission (40) from the engine speed sensor (66), the vehicle speed sensor (67), and the gear ratio stored in the table (85);
A display unit (77) for displaying the travel speed calculated by the control unit (65);
In a working vehicle characterized by comprising:

According to the second aspect of the present invention, the rotation from the engine (12) is transmitted to the PTO shaft (61) through the multi-stage transmission (40) and also transmitted to the drive wheels (16, 17), and the PTO shaft (61 ) In the working vehicle (10) that travels the vehicle body while operating the working machine (26) by the output from
An engine speed sensor (66) for detecting the speed of the engine (12);
A PTO rotational speed sensor (68) for detecting the rotational speed of the output section of the multi-stage transmission (40);
A table (85) for storing the gear ratio of each gear stage of the multi-stage transmission (40);
A control unit (65) for calculating a gear position of the multi-stage transmission (40) from the engine speed sensor (66), the PTO speed sensor (68), and the gear ratio stored in the table (85). When,
A display unit (77) for displaying the PTO shift speed calculated by the control unit (65);
In a working vehicle characterized by comprising:

According to a third aspect of the present invention, the multi-stage transmission (40) includes a forward / reverse rotation mechanism (45) for switching forward / reverse rotation,
A forward / reverse sensor (70) for detecting the forward / reverse position of the forward / reverse mechanism (45) is provided,
The table (85) has a forward rotation table (86) and a reverse rotation table (87),
The controller (65) selects the forward rotation or reverse rotation tables (86, 87) based on the forward / reverse rotation sensor (70), and calculates the forward rotation speed stage or the reverse rotation speed stage.
The working vehicle according to claim 1 or 2, wherein

  In addition, the code | symbol in the above-mentioned parenthesis is for referring drawings, Comprising: This invention is not limited at all.

  According to the first aspect of the present invention, not only the engine speed and the vehicle speed (travel speed) but also the current travel speed can be displayed, and the operator can appropriately perform the work based on the information. .

  According to the second aspect of the present invention, not only the engine speed and the PTO speed, but also the current PTO speed can be displayed. In particular, the PTO shift lever is in a position that is difficult for the operator to see and it is difficult to grasp the PTO shift speed, but it can be displayed at a position where the PTO shift speed is easy to see, and the operator can perform appropriate work based on these information. It can be carried out.

  In addition, since the travel shift stage or the PTO shift stage is calculated from the input side rotational speed and the output side rotational speed of the multi-stage transmission, it does not require many switches such as detecting the operation position of the shift lever, and Low-cost and highly reliable gear position display can be performed without wiring.

  According to the third aspect of the present invention, there is a gear stage having a gear ratio close to the forward (forward) side and the reverse (backward) side, and the gear ratio is changed only by the ratio of the input / output side rotational speed of the multi-stage transmission. Although it may be difficult to determine the speed, the forward rotation table and the reverse rotation table can be selected by the forward / reverse rotation sensor, and accurate gear position display can be performed even during forward rotation or reverse rotation.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 is a side view of a tractor connected to a work machine, FIG. 2 is a configuration diagram showing a power transmission system of the tractor shown in FIG. 1, and FIG. 3 is a block diagram showing a control device for the tractor shown in FIG. FIG. 4 is a diagram showing an example of a table stored in the control device, FIG. 5 is a diagram showing an example of a margin rate table when comparing the engine speed and the vehicle speed, and FIG. 6 is a control device shown in FIG. FIG. 7 is a program flowchart for setting the measurement timing of the vehicle speed.

  As shown in FIG. 1, a tractor 10 as a working vehicle has an engine 12 mounted on the front, and a clutch housing 13, a center case 13, and a transmission case 15 are integrally connected to the rear of the engine 12. Accordingly, the front wheels 16 and the rear wheels 18 are driven by the drive of the engine 12. An upper part of the clutch housing 13, the center case 14, and the transmission case 15 constitutes an airframe frame 20. A fender frame 21, a seat seat 23, a steering column 24, and a steering wheel 25 and the like are disposed on the rear part thereof.

  A work machine 26 is connected to the rear part of the machine body frame 20, and the work machine 26 is moved up and down by a lift arm 28 that is hydraulically driven. Further, a radiator fan 30 and a battery (not shown) are disposed on the front surface of the engine 12 at the front of the body frame 20, and the outer peripheral space of the engine 12, the radiator fan 30, and the like is covered with a bonnet 32. .

  As shown in FIG. 2, the power transmission system of the tractor 10 includes a travel drive system 37 driven by a transmission shaft 36 driven by the engine 12 via a main clutch 35, a work implement drive system 50, It has.

  The travel drive system 37 includes a multi-stage transmission 40, which includes a first main transmission mechanism 41 that switches from the neutral stage to the first speed stage or the second speed stage, and a neutral stage. And a second main transmission mechanism 42 that switches to the third speed stage or the fourth speed stage.

  Further, the travel drive system 37 includes a hydraulic clutch 43 arranged on the output side of the multi-stage transmission 40, a forward / reverse mechanism 45 that directly or reverses the output rotation of the hydraulic clutch 43, and the forward / reverse mechanism 45 A first subtransmission mechanism 46 that switches the output rotation between the H and L stages, and a second subtransmission that switches the output rotation of the first subtransmission mechanism 46 between the H and L stages. A mechanism 47, a differential device 48 that transmits the output rotation of the second auxiliary transmission mechanism 47 to the rear wheel 17, and a differential mechanism 50 that transmits the output rotation of the second auxiliary transmission mechanism 47 to the front wheel 16. is doing.

  The work implement drive system 55 rearwardly outputs the first PTO transmission mechanism 56 and the second PTO transmission mechanism 57 that branch the output rotation of the engine 12 via the multi-stage transmission 40, and the output rotation of the first and second PTO transmission mechanisms. And a third PTO transmission mechanism 60 for shifting the output rotation of the electric shaft 58, and a PTO shaft 61 for transmitting the output rotation to the work implement 26.

  As shown in FIG. 3, the control part 65 of the tractor 10 which has the said power transmission system is comprised by the microcomputer unit (microcomputer unit). On the input side of the control unit 65, an engine speed sensor 66 that detects the speed of the engine 12, and a vehicle speed sensor 67 that detects the speed of the axle that is rotationally driven through the differential device 50, as a vehicle speed, A PTO rotational speed sensor 68 for detecting the rotational speeds of the output portions of the first and second PTO transmission mechanisms of the multi-stage transmission 40 is connected.

  Further, the control unit 65 detects the traveling speed of the tractor 10 and the operating position of the shuttle lever (not shown) for performing the forward / reverse operation to the reverse side (that is, the reverse rotation of the forward / reverse rotation mechanism 45). A shuttle R switch 70 is connected. That is, the shuttle R switch 70 becomes a forward / reverse sensor.

  Further, on the input side of the control unit 65, in addition to the engine speed sensor 66, the vehicle speed sensor 67, the PTO speed sensor 68 and the shuttle R switch 70, a PTO / R switch 71, an INDPTO switch 72, a position control system sensor , Switch 73, depth control system sensor, switch 75, tilt control system sensor, switch 76, and the like are connected.

  On the output side of the control unit 65, in addition to a display unit 77 composed of a notification LCD unit, a position control system bulb / lamp output 78, a depth control system bulb / lamp output 80, a tilt control system bulb / lamp output 81 etc. are connected.

  The control unit 65 stores tables as shown in FIGS. FIG. 4 shows a table 85 for calculating the speed of the vehicle speed. The forward table 86 is used when the tractor 10 is moving forward, and the reverse table 87 is used when calculating the speed of the tractor 10 when moving backward. Is done. FIG. 5 shows an example of a margin ratio table 88 indicating a margin ratio applied when comparing the output of the vehicle speed sensor 67 with the vehicle speed of the forward travel table 86 or the reverse travel table 87. In other words, the margin ratio table 88 is for determining the shift speed at the low speed limit at each shift speed, and the margin ratio is set so as not to overlap with the speed at the other shift speed.

  With reference to the program flowchart shown in FIG. 6, the control process for displaying the traveling shift speed (shift state) with the above configuration will be described.

  The vehicle speed of the tractor 10 is measured (step S1 in FIG. 6, hereinafter simply referred to as step S). The vehicle speed sensor 67 detects the rotation speed of the front wheel 16 or the rear wheel 17 per unit time, and calculates the movement speed per hour from the rotation speed and the movement amount of the tractor 10 per rotation of the front wheel 16 or the rear wheel 17. To measure.

  Based on the output of the engine speed sensor 66, it is determined whether or not the engine 12 is in operation (step S2). If it is determined in step S2 that the engine 12 is stopped, "0" is set to the gear position (step S3).

  When the engine 12 is in operation at step S2, the forward / backward movement of the tractor 10 is determined based on the output of the vehicle speed sensor 67 and the opening / closing of the shuttle R switch 70 (step S4). When the tractor 10 is moving forward, the process based on the forward moving table 86 is selected (step S5), and when the tractor 10 is moving backward, the reverse moving table is selected (step S6) and the margin rate table is selected. 88 is set.

  The reduction ratio I of the selected forward table 86 or reverse table 87 is set (step S7). The speed reduction ratio I is set to the speed reduction ratio I at the highest speed stage during the 16-speed shift, and then set to the speed reduction ratio I lowered by one stage. Comparison data is calculated based on the margin ratio selected from the engine rotation sensor 67, the reduction ratio I, and the margin ratio table 88 (step S8).

  The speed of the tractor 10 measured in step S1 is compared with the comparison data calculated in step S8 (step S9). If the speed of the tractor 10 is greater than the comparison data in step S9, a deceleration stage that is one step higher than the deceleration stage of the reduction ratio I set in step S7 is set (step S10).

  If the speed measured in step S9 is smaller than the comparison data, a speed reduction ratio obtained by lowering the speed reduction ratio I set in step S6 by one step is selected (step S11). It is determined whether or not the reduction ratio I is smaller than “0” (step S12). When the reduction ratio I is larger than “0”, the steps S8, S9, and S11 are repeated.

  If the gear ratio I is smaller than “0” in step S12, “0” is set in the gear position (step S13). The shift stage set in step S3, step S10 and step S13 is displayed on the display unit 77 (step S14).

  By using the output of the PTO rotation speed sensor 68 instead of the output of the vehicle speed sensor 67, the speed of the PTO shaft 61 is also displayed on the display unit 77 in the same control process as when displaying the speed of the vehicle speed. Can be displayed.

  As described above, by displaying the PTO shift speed on the display unit 77, it is possible to easily grasp the PTO shift speed due to the operation of the PTO shift lever, which is normally in a position difficult for the operator to see. Therefore, the operator can appropriately perform work based on such information.

  Further, although the gear ratios at the time of forward / reverse rotation are different, by storing the forward movement table 86 and the backward movement table 87 as the table 85, it is possible to measure the accurate gear position, respectively, and at the time of forward movement and reverse movement, respectively. Speed display can be performed.

  When the speed change operation of the tractor 10 or the work machine 26 is performed, a predetermined time is required until the rotation of the front wheel 16 or the rear wheel 17 or the PTO shaft 61 is stabilized in the state where the speed change operation is performed. For this reason, immediately after the speed change operation, the engine speed sensor 66, the vehicle speed sensor 67, and the PTO speed sensor 68 outputs become unstable, and the shift speed may be erroneously determined. In order to prevent such an erroneous determination, it is necessary to maintain the state before the shift operation for a certain period of time after the shift operation and to determine a new shift stage in which the shift operation is performed after the lapse of the fixed time.

  A control process for measuring the passage of time will be described with reference to a program flowchart shown in FIG.

  It is determined whether or not the measurement time has timed out (step S21 in FIG. 7, hereinafter simply referred to as step OO). If the measurement time is up, the measurement time is cleared (step S22), and the process returns to step 21.

  If the measurement time is not up, it is determined whether or not a clock pulse has been input (step S23). If no clock pulse has been input, the process returns to step S21. If a clock pulse is input in step S23, the number of pulses is counted (step S24).

  It is determined whether or not the count number in step S24 has reached a preset sampling number (step S25). If the counted number of pulses does not reach the preset number of samples, the steps S21 to S24 are repeated. If the number of pulses reaches the preset number of samples, the measurement start signal for the gear position is started and the pulse number count is cleared (step S26). A new measurement time is set (step S27), the time-out data is cleared (step S28), and the process returns to step S21.

  As described above, the shift stage can be measured in a stable state by starting measurement of the shift stage after a predetermined time has elapsed.

It is a side view of the tractor which connected the work machine. It is a block diagram which shows the power transmission system of the tractor shown in FIG. It is a block diagram which shows the control apparatus of the tractor shown in FIG. It is a figure which shows an example of the table stored in a control apparatus. It is a figure which shows an example of the margin ratio table at the time of comparing an engine speed and a vehicle speed. It is a program flowchart which shows the control process in the control apparatus shown in FIG. It is a program flowchart for setting the measurement timing of the vehicle speed.

Explanation of symbols

10 Working vehicle (tractor)
12 Engine 16 Drive wheel (front wheel)
17 Drive wheel (rear wheel)
26 Working Machine 40 Multi-speed Transmission 45 Forward / Reverse Mechanism 61 PTO Shaft 65 Control Unit 66 Engine Speed Sensor 67 Vehicle Speed Sensor 68 PTO Speed Sensor 70 Forward / Reverse Sensor (Shuttle R Switch)
77 Display 85 Table 86 Forward rotation table 87 Reverse rotation table

Claims (3)

In a working vehicle that transmits the rotation from the engine to the drive wheel via the multi-stage transmission and travels the vehicle body,
An engine speed sensor for detecting the engine speed;
A vehicle speed sensor for detecting the rotational speed of the output section of the multi-stage transmission,
A table for storing a gear ratio of each gear of the multi-stage transmission;
A control unit that calculates a gear position of the multi-stage transmission from the engine speed sensor, the vehicle speed sensor, and a gear ratio stored in the table;
A display unit for displaying the travel speed calculated by the control unit;
A working vehicle comprising: In a working vehicle that travels the vehicle body while transmitting the rotation from the engine to the PTO shaft via the multi-stage transmission and the driving wheel, and operating the work machine by the output from the PTO shaft,
An engine speed sensor for detecting the engine speed;
A PTO rotational speed sensor for detecting the rotational speed of the output portion of the multi-stage transmission,
A table for storing a gear ratio of each gear of the multi-stage transmission;
A control unit that calculates a gear position of the multi-stage transmission from the engine speed sensor, the PTO speed sensor, and a gear ratio stored in the table;
A display unit for displaying the PTO shift speed calculated by the control unit;
A working vehicle comprising: The multi-stage transmission has a forward / reverse mechanism for switching forward / reverse,
A forward / reverse sensor for detecting the forward / reverse position of the forward / reverse mechanism is provided,
The table has a normal rotation table and a reverse rotation table,
The control unit selects the forward rotation or reverse rotation table based on the forward / reverse rotation sensor, and calculates the forward rotation speed stage or the reverse rotation speed stage.
The working vehicle according to claim 1 or 2, wherein

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