JP2007008291A - Self-propelled plant management machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a management machine having a control function capable of surely avoiding engine failure. <P>SOLUTION: A first velocity instruction value C1 and a velocity ratio (Vact/Vset) are read into an instruction value conversion part 61, and a second velocity instruction value C2 is outputted by operation of (Vact/Vset)×C1=C2. A rotating speed of the output shaft 47L of a left hydraulic transmission 22L is detected by a traveling speed detection means 52L. A left transmission control part 62L compares the actual rotating speed detected by the detection means 52L with the second velocity instruction value C2, and drives a control motor 48L through a motor driver 63L so that the actual rotating speed gets close to the second velocity instruction value C2. The same operation is performed in a right transmission control part 62R. According to this, the second velocity instruction value is smaller as the load to the engine is larger. Consequently, engine failure can be avoided. Further, the traveling speed is automatically controlled according to the engine load without needing a worker's decelerating operation. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a self-propelled management machine that performs farming operations such as tillage and weeding in a working unit while moving a machine body and a working unit in a traveling unit.

A self-propelled management machine is an agricultural machine that performs agricultural work while self-propelled by driving a traveling unit and a working unit with an engine. Some self-propelled management machines drive a traveling unit and a working unit with a single engine for the purpose of miniaturization, weight reduction, and cost reduction (see, for example, Patent Document 1).
JP 2000-262103 A (FIG. 3)

Patent document 1 is demonstrated based on the following figure.
FIG. 6 is a diagram for explaining the basic configuration of the prior art. In the management machine 100, the intermediate shaft 102 is rotated by the output shaft 101 of the engine, and the working unit input shafts 103 and 104 are rotated by the intermediate shaft 102. The working unit shaft 105 is rotated by the working unit input shafts 103 and 104, and the tilling claw 106 provided on the working unit shaft 105 is turned to perform tilling.
Further, the intermediate shaft 102 is rotated by the output shaft 101 of the engine, the input shaft 111 of the fluid transmission 110 is rotated by the intermediate shaft 102, the speed is changed by the fluid transmission 110, and the differential 113 is transmitted by the output shaft 112 of the fluid transmission 110. The left and right drive wheels 114 and 115 are rotated by the differential 113 and the vehicle travels.

  That is, the management machine 100 of Patent Document 1 drives the working unit 116 and the traveling unit 117 with the output shaft 101 of one engine. The working unit 116 is directly driven by the engine, and the traveling unit 117 is driven by the engine to drive the fluid transmission 110, and is shifted by the fluid transmission 110 to rotate the drive wheels 114 and 115.

Since the fluid transmission 110 is employed, the engine can operate at one target rotational speed, and an arbitrary traveling speed can be obtained by the speed change action of the fluid transmission 110.
Although not specified in Patent Document 1, feedback control of the fluid transmission 110 is generally performed so that the traveling speed specified by the operator is obtained.
In other words, the riding management machine can secure the amount of work per hour by stabilizing the traveling speed, and the walking speed is stabilized in the walking type management machine that the operator carries with the aircraft. Thus, the worker's walking speed becomes constant, and the worker's fatigue can be reduced.

However, it has been found that the following problems occur when the fluid transmission 110 is feedback-controlled.
When the load on the working unit increases rapidly due to the tillage nail biting into soil harder than the surroundings, this increase in load affects the engine, and the rotational speed of the engine decreases. When the rotational speed of the engine decreases, the traveling speed decreases. This decrease in travel speed can also be detected by the output shaft of the fluid transmission.

Feedback control is activated, and the gear ratio in the fluid transmission is automatically changed so that the rotational speed of the output shaft of the fluid transmission becomes the specified speed. An attempt is made to restore the traveling speed, but the load on the engine further increases, and the rotational speed of the engine further decreases. This vicious cycle causes engine stoppage, so-called engine stall.
Therefore, a skilled worker senses changes in engine sound and changes in resistance at the steering wheel, and operates the travel speed lever to the deceleration side to avoid engine stall.

  Thus, the conventional management machine that drives the traveling unit and the working unit with a single engine has a high frequency of engine stalls, and skill is required to avoid engine stalls. However, there is a demand for a management machine that can easily avoid engine stall even for unskilled workers.

  It is an object of the present invention to provide a management machine having a control function that can reliably avoid engine stall.

  The invention according to claim 1 is provided with a working unit, a traveling unit, and an engine in the fuselage, the engine is basically operated at one target rotational speed, and the working unit is directly driven by such an engine, The traveling unit drives a fluid transmission with an engine, and in the self-propelled management machine driven by the fluid transmission, the self-propelled management machine measures the rotational speed of the output shaft of the engine. Means, a traveling speed detecting means for measuring the speed of the traveling section, a speed ratio calculating section for calculating a speed ratio using the actual rotational speed measured by the engine speed detecting means as a numerator and the target rotational speed as a denominator, A traveling speed lever operated by an operator when adjusting the traveling speed of the airframe, and a command value conversion to obtain a secondary speed command value by multiplying the primary speed command value generated by the traveling speed lever by the speed ratio. Department and this A transmission control unit that feedback-controls the fluid transmission so that the speed of the traveling unit detected by the traveling speed detection unit matches the secondary speed command value generated by the command value conversion unit. To do.

  The invention according to claim 2 is provided with a working unit, a traveling unit, an engine, and a generator on the airframe, and the engine is basically operated at one target rotational speed, and the working unit is directly operated by such an engine. In the self-propelled management machine of the type in which the traveling unit drives the generator with an engine, drives the electric motor with electricity obtained by the generator, and is driven by the electric motor, the self-propelled management machine Engine speed detecting means for measuring the rotational speed of the output shaft of the engine, traveling speed detecting means for measuring the speed of the traveling portion, and the target rotational speed using the actual rotational speed measured by the engine speed detecting means as a numerator. A speed ratio calculation unit for calculating a speed ratio with the speed as a denominator, a travel speed lever operated by an operator when adjusting the travel speed of the aircraft, and a primary speed command value generated by the travel speed lever Speed ratio A command value conversion unit that multiplies it to obtain a secondary speed command value, and the electric speed so that the speed of the traveling unit detected by the traveling speed detection means matches the secondary speed command value generated by the command value conversion unit. And a transmission control unit that feedback-controls the motor.

  In the invention according to claim 1, the traveling speed is controlled by the secondary speed command value obtained by multiplying the primary speed command value based on the operator's command by a speed ratio of less than 1.0. The secondary speed command value decreases as the load on the engine increases. That is, the control is performed to decrease the traveling speed as the load increases. As a result, engine stall can be avoided. Furthermore, it is not necessary for the operator to manually decelerate, and the traveling speed is automatically controlled according to the engine load. Therefore, it is possible to reduce the burden on the operator regarding the traveling speed operation.

  In the invention according to claim 2, the traveling speed is controlled by the secondary speed command value obtained by multiplying the primary speed command value based on the operator's command by a speed ratio of less than 1.0. The secondary speed command value decreases as the load on the engine increases. That is, the control is performed to decrease the traveling speed as the load increases. As a result, engine stall can be avoided. Furthermore, it is not necessary for the operator to manually decelerate, and the traveling speed is automatically controlled according to the engine load. Therefore, it is possible to reduce the burden on the operator regarding the traveling speed operation.

  In addition, according to the second aspect, the traveling unit is driven by an electric motor. If the engine and the traveling unit are mechanically connected, the drive system becomes complicated. However, in the present invention, the traveling unit is driven by the electric motor, so the mechanical drive system becomes unnecessary, and the electric power line and signal It is possible to simplify the structure of the self-propelled management machine by simply laying the wire.

The best mode for carrying out the present invention will be described below with reference to the accompanying drawings. In the following description, front / rear, left / right, and upper / lower are determined based on the passenger sitting on the passenger seat. The drawings are viewed in the direction of the reference numerals.
FIG. 1 is a side view of a self-propelled management machine according to the present invention. A self-propelled management machine 10 includes a front wheel frame 12 that can be steered left and right at a front portion of a body 11 formed of a steel frame and a steel plate. A front wheel 13 is provided below the front wheel frame 12, a front wheel motor 14 for driving the front wheel 13 is provided at a substantially center of the front wheel frame 12, and various operations such as sowing, plowing and weeding are carried out behind the front wheel frame 12. The vehicle 15 includes a driver seat 17 on which an occupant sits, and a rear wheel 18L, 18R (rear wheels on the left side) that serve as driving wheels. Front wheel 18L and 18R (only the left rear wheel 18L is shown) and the engine 21 and fluid transmissions 22L and 22R (only the left fluid transmission 22L is shown) before. 1 wheel, rear An agricultural machine of the wheel.

  Reference numeral 23 is a steering handle for the front wheel 13, 24 and 24 are steering rods interposed between the handle 23 and the front wheel frame 12, 25 is a steering shaft for the front wheel 13, 26 is a silencer, and 27 is a lifting cylinder.

The working unit shaft 31 is disposed in the lower part of the machine body 11 in the front-rear direction, the relay shaft 32 is connected to the front portion of the working unit shaft 31, and the input shaft 33 of the working unit 15 is attached to the relay shaft 32. Power transmission between the rear output shaft 34 of the engine 21 and the working unit shaft 31 is performed by a pair of pulleys 35 and 36 attached to the shafts 34 and 31 and a belt 37 wound around the pulleys 35 and 36. Is. Universal joints 38 and 39 are provided before and after the relay shaft 32.
The drive system for the rear wheels 18L and 18R (only the left rear wheel 18L is shown) will be described in the next figure.

  FIG. 2 is a principle diagram of a drive system of a self-propelled management machine according to the present invention. The sum of the inputs to. However, if the electromagnetic clutch 43 provided on the front output shaft 42 of the engine 21 and the electromagnetic clutch 44 provided on the rear output shaft 34 are disengaged, all the force of the engine 21 is sent to drive the generator 41. Can do. All the power generated by the generator 41 is stored in the battery 45.

The fluid transmissions 22L and 22R, usually called HST (Hydrotic transmission), incorporate a variable displacement swash plate type hydraulic pump and a hydraulic motor, and drive the hydraulic pump with input shafts 46L and 46R to generate hydraulic pressure. The oil having the hydraulic pressure is supplied to the hydraulic motor to rotate the hydraulic motor and output it to the output shafts 47L and 47R of the fluid transmissions 22L and 22R. By changing the inclination angle of the swash plate from the outside, The output shafts 47L and 47R can be accelerated, decelerated, forwardly rotated, stopped, and reversely rotated while the input shafts 46L and 46R are rotated at a constant speed.
In this embodiment, the swash plate is indirectly controlled by the control motors 48L and 48R.

  And the engine speed detection means 51 is connected with the front part output shaft 42 of the engine 21 via a pulley and a belt. The engine speed detecting means 51 is preferably an alternator called an alternator. The speed can be obtained from the generated AC frequency.

Further, the traveling speed detection means 52L is connected to the output shaft 47L of the left fluid transmission 22L, and the traveling speed detection means 52R is connected to the output shaft 47R of the right fluid transmission 22R. The travel speed detection means 52L may be of any type, type, and location as long as it is a rotation sensor that can detect the travel speed of the left rear wheel 18L directly or by conversion.
Therefore, the traveling speed detection means 52L may be provided anywhere between the output shaft 47 and the rear wheel 18L. In this embodiment, the traveling speed detecting means 52L is provided on the output shaft 47 for convenience. The same applies to the right traveling speed detection means 52R.

  FIG. 3 is a configuration diagram of the control unit according to the present invention. First, the target rotational speed Vset of the engine 21 is set by the setting means 54. This target rotational speed Vset is a constant value that is determined in advance with reference to the rated rotational speed of the engine 21. Further, the rotational speed of the output shaft of the engine 21 is detected by the engine speed detecting means 51 and converted into the actual rotational speed Vact by the converter 55. Then, the target rotation speed Vset and the actual rotation speed Vact are read into the speed ratio calculation unit 56, and the speed ratio (Vact / Vset) is calculated. This speed ratio (Vact / Vset) is generally less than 1.0.

  On the other hand, the operation amount (angle or distance) of the traveling speed lever 57 operated by the operator is detected by a sensor 58, and information from the sensor 58 is converted into speed information by a changer 59. This speed information is referred to as a primary speed command value C1. Then, the first speed command value C1 and the speed ratio (Vact / Vset) are read into the command value conversion unit 61, and the second speed command value C2 is output by the calculation of (Vact / Vset) × C1 = C2.

  Further, the rotational speed of the output shaft 47L of the left fluid transmission 22L is detected by the traveling speed detection means 52L. The left transmission control unit 62L compares the actual rotational speed detected by the traveling speed detection means 52L with the second speed command value C2, and sets the motor driver 63L so that the actual rotational speed approximates the second speed command value C2. Via the control motor 48L. The same applies to the right transmission control unit 62R.

It is assumed that the primary speed command value C1 is 100, and the load acting on the engine 21 increases rapidly and the speed ratio becomes 0.95. Then, the secondary speed command value C2 becomes 95 and the traveling speed becomes 95.
That is, even if the instruction of the traveling speed lever 57 is 100, when the engine load increases rapidly, the traveling speed is automatically reduced to 95 to reduce the engine load. As a result, the engine stall can be eliminated. Further, since it is not necessary to manually perform an operation for avoiding engine stall, the operation required by the operator is facilitated.

The above configuration is summarized as follows. Reference numerals refer to FIGS.
The body 11 includes a working unit 15, a traveling unit (rear wheels 18L and 18R), and an engine 21. The engine 21 is basically operated at one target rotational speed Vset. In the self-propelled management machine 10 of the type which drives directly, and a run part (rear wheels 18L and 18R) drives fluid transmissions 22L and 22R with engine 21, and drives with these fluid transmissions 22L and 22R,
The self-propelled management machine 10 includes an engine speed detection unit 51 that measures the rotation speed of the output shaft of the engine 21, traveling speed detection units 52 </ b> L and 52 </ b> R that measure the speed of the traveling unit 15, and an engine speed detection unit 51. A speed ratio calculation unit 56 for calculating a speed ratio (Vact / Vset) using the measured actual rotational speed Vact as a numerator and a target rotational speed Vset as a denominator; and a travel operated by an operator when adjusting the travel speed of the airframe 11 A speed lever 57, a command value conversion unit 61 that multiplies a primary speed command value C1 generated by the travel speed lever 57 by a speed ratio (Vact / Vset) to obtain a secondary speed command value C2, and the command value The fluid transmission 2 is set so that the speed of the traveling unit (rear wheels 18L, 18R) detected by the traveling speed detection means 52L, 52R matches the secondary speed command value C2 generated by the converter 61. L, 22R feedback control of the transmission control unit 62L, characterized in that it comprises a 62R.

  In the embodiment, the left and right rear wheels 18L and 18R are provided with fluid transmissions 22L and 22R, respectively, and the fluid transmissions 22L and 22R are provided with transmission control units 62L and 63R. , 18R are connected by one differential, this differential is driven by one fluid transmission, and one transmission control unit is provided in this fluid transmission, so that the number of fluid transmissions and transmission control units is increased. May be halved.

Next, another embodiment will be described.
2 and 3, the fluid transmissions 22L and 22R are replaced with electric motors.
FIG. 4 is a diagram showing another embodiment of FIG. 2, and the same parts as those in FIG. That is, the left rear wheel 18L is driven by the electric motor 65L, the traveling speed detection means 52L is connected to the output shaft 66L of the electric motor 65L, and the right rear wheel 18R is driven by the electric motor 65R. The traveling speed detecting means 52R is connected to the output shaft 66R of the electric motor 65R.

  Since the electric motors 65L and 65R are driven by the battery 45, the front output shaft of the engine 21 can be omitted, most of the drive system from the engine 21 to the rear wheels 18L and 18R can be omitted, and the structure is simple. Can be achieved.

FIG. 5 is a diagram of another embodiment of FIG. 3, and the same parts as those in FIG.
The traveling speed detecting means 52L detects the rotational speed of the output shaft 66L of the left electric motor 65L. The left transmission control unit 62L compares the actual rotational speed detected by the traveling speed detection means 52L with the second speed command value C2, and sets the motor driver 67L so that the actual rotational speed approximates the second speed command value C2. The electric motor 65L is controlled via The same applies to the right transmission control unit 62R.

The above configuration is summarized as follows. Reference numerals refer to FIGS. 1 and 4 to 5.
The body 11 includes a working unit 15, a traveling unit (rear wheels 18L and 18R), and an engine 21. The engine 21 is basically operated at one target rotational speed Vset. The driving part (rear wheels 18L, 18R) drives the generator 45 with the engine 21 and drives the electric motors 65L, 65R with electricity obtained by the generator 45, and the electric motors 65L, 65R are driven directly. In the self-propelled management machine 10 of the type driven by
The self-propelled management machine 10 includes an engine speed detection unit 51 that measures the rotation speed of the output shaft of the engine 21, traveling speed detection units 52 </ b> L and 52 </ b> R that measure the speed of the traveling unit 15, and an engine speed detection unit 51. A speed ratio calculation unit 56 for calculating a speed ratio (Vact / Vset) using the measured actual rotational speed Vact as a numerator and a target rotational speed Vset as a denominator; and a travel operated by an operator when adjusting the travel speed of the airframe 11 A speed lever 57, a command value conversion unit 61 that multiplies a primary speed command value C1 generated by the travel speed lever 57 by a speed ratio (Vact / Vset) to obtain a secondary speed command value C2, and the command value The electric motor 6 is adapted so that the speed of the traveling parts (rear wheels 18L, 18R) detected by the traveling speed detection means 52L, 52R matches the secondary speed command value C2 generated by the converter 61. L, transmission control section 62L for feedback control of the 65R, characterized in that it comprises a 62R.

  Note that the self-propelled management machine of the present invention may be either a riding management machine or a walking management machine. The traveling unit may be a crawler.

  The present invention is basically provided with a working unit, a traveling unit, and an engine, and the engine is operated at one target rotational speed. The working unit is directly driven by such an engine, and the traveling unit is an engine. This is suitable for a self-propelled management machine of a type in which a fluid transmission is driven by this fluid transmission.

It is a side view of the self-propelled management machine concerning the present invention. It is a principle figure of the drive system of the self-propelled management machine concerning the present invention. It is a block diagram of the control part which concerns on this invention. It is another Example figure of FIG. It is another Example figure of FIG. It is a figure explaining the basic composition of the conventional technology.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Self-propelled management machine, 11 ... Airframe, 15 ... Working part, 18L, 18R ... Rear wheel as running part, 21 ... Engine, 22L, 22R ... Fluid transmission, 34, 42 ... Output shaft of engine, 51 ... Engine speed detection means, 52L, 52R ... Travel speed detection means, 56 ... Speed ratio calculation section, 57 ... Travel speed lever, 61 ... Command value conversion section, 62L, 62R ... Transmission control section, 65L, 65R ... Electric motor , 66L, 66R, output shaft of the electric motor, Vset, target rotational speed, Vact, actual rotational speed, Vact / Vset, speed ratio, C1, primary speed command value, C2, secondary speed command value.

Claims (2)

The airframe is provided with a working unit, a traveling unit, and an engine. This engine is basically operated at one target rotational speed, and the working unit is directly driven by such an engine. In the self-propelled management machine of the type driven by this fluid transmission,
This self-propelled management machine includes an engine speed detecting means for measuring the rotational speed of the output shaft of the engine, a traveling speed detecting means for measuring the speed of the traveling portion, and an actual rotational speed measured by the engine speed detecting means. A speed ratio calculation unit for calculating a speed ratio with the target rotation speed as a denominator, a travel speed lever operated by an operator when adjusting the travel speed of the aircraft, and a first generated by the travel speed lever A command value conversion unit for multiplying the next speed command value by the speed ratio to obtain a second speed command value, and a travel unit detected by the travel speed detection means on the second speed command value generated by the command value conversion unit A self-propelled management machine comprising: a transmission control unit that feedback-controls the fluid transmission so that the speeds of the fluid transmissions match. The airframe is equipped with a working unit, a traveling unit, an engine, and a generator. This engine is basically operated at one target rotational speed, and the working unit is directly driven by such an engine, and the traveling unit is an engine. In the self-propelled management machine of the type which drives the generator, drives the electric motor with the electricity obtained by the generator, and is driven by the electric motor,
This self-propelled management machine includes an engine speed detecting means for measuring the rotational speed of the output shaft of the engine, a traveling speed detecting means for measuring the speed of the traveling portion, and an actual rotational speed measured by the engine speed detecting means. A speed ratio calculation unit for calculating a speed ratio with the target rotation speed as a denominator, a travel speed lever operated by an operator when adjusting the travel speed of the aircraft, and a first generated by the travel speed lever A command value conversion unit for multiplying the next speed command value by the speed ratio to obtain a second speed command value, and a travel unit detected by the travel speed detection means on the second speed command value generated by the command value conversion unit A self-propelled management machine comprising: a transmission control unit that feedback-controls the electric motor so that the speeds of the electric motors match.

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