JPH03249479A - Device for controlling running of working vehicle - Google Patents

Abstract

PURPOSE:To providing a safe working operation by providing a differential motion release control means for carrying out automatic speed governing control so as to change the running speed while preventing a vehicle body from obliquely moving due to a difference in drive speed between left and right running devices. CONSTITUTION:In order to change the running direction of a vehicle body, since a control change-over means 25 prevents a differential motion release control means 24 from operating, a difference in speed between first and second continuously variable transmissions can be obtained so that the vehicle body can be steered. In order to change the running speed of the vehicle body, the control change-over means 25 enables the differential motion release control means 24 to automatically adjust the manipulating speed of a manipulating section in accordance with data from a differential motion sensor S3 so that a difference in turning stroke between first and second manipulating sections does not produce, completely or subsantially completely. Accordingly, either during a desired period by which the running speed reaches a desired control speed or during progress of speed change, the first and second continuously variable transmissions change the speeds which can coincide with each other as far as possible.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention provides a hydraulic first drive system that drives left and right traveling devices separately.
A continuously variable transmission and a second continuously variable transmission are provided, and a first operating section of the first continuously variable transmission and a second continuously variable transmission of the second continuously variable transmission are provided.
A first drive mechanism and a second drive mechanism are provided that operate the operation section separately, and the first continuously variable transmission and the second drive mechanism are provided.
The first speed is brought into a state in which the speed exhibited by each of the continuously variable transmissions is equal to or approximately equal to the speed set by the speed change operation means.
A speed change control means for automatically operating a drive mechanism and the second drive mechanism, and a steering operation means in which the difference between the speed exhibited by the first continuously variable transmission and the speed developed by the second continuously variable transmission is controlled by a steering operation means. The present invention relates to a traveling control device for a work vehicle, which is provided with a steering control means for automatically operating the first drive mechanism and the second drive mechanism to a state where the speed difference is equal to or approximately equal to a set speed difference.

[Conventional technology]

In the work vehicle, the continuously variable transmission is operated by each of the first and second drive mechanisms so that the left and right traveling devices increase or decrease to the same control target speed by performing a set speed change operation using the speed change operation means. so that the traveling speed of the aircraft increases or decreases, and by changing the set speed difference using the steering operation means, a difference occurs between the speed of one traveling device and the speed of the other traveling device. The continuously variable transmission is operated by the first and second drive mechanisms to change the traveling direction of the aircraft.

Conventionally, in this type of work vehicle, when increasing and decelerating operations are performed to change the left and right traveling devices to the same control target speed,
On both the first continuously variable transmission side and the second continuously variable transmission side, the speed change operation from the speed before the speed change operation to the control target speed is an independent operation that is not related to the speed change operation on the other continuously variable transmission side. It was supposed to be held in

[Problem to be solved by the invention]

Conventionally, when the left and right traveling gears are accelerated or decelerated to the same control target speed, there is a difference between the left traveling gear speed and the right traveling gear speed in the process of the left and right traveling gears reaching the control target speed, so that the aircraft does not reach the desired speed. Sometimes this was accompanied by skewing in a direction that was different from the one shown. This is due to the fact that the shift operation resistance caused by the operating condition of the interlocking mechanism between the transmission operation part and the drive mechanism differs between the first continuously variable transmission side and the second continuously variable transmission side, and as shown in Fig. 8. As shown, one of the continuously variable transmissions (T+) changes from the pre-shift speed (■.) to the control target speed (V).
On the other hand, the other continuously variable transmission (T2) changes from the pre-shift speed (Vo) to the control target speed (V) in a longer time (t1) than the required time (t1).
T2), or as shown in FIG. 9, both continuously variable transmissions (T1) and (T2) change to the control target speed (■) in the same required time (1). This is because the speed change progress of one continuously variable transmission (T1) may be different from the shift progress of the other continuously variable transmission (T2).

An object of the present invention is to provide a control device that is less likely to cause skew even when there is the difference in speed change resistance and is advantageous in terms of structure.

[Means to solve the problem]

In order to achieve the purpose of the traveling control device for a working vehicle according to the present invention, in the working vehicle described at the beginning, the difference between the rotational stroke of the first operating section and the rotational stroke of the second operating section is provided. A main body of a differential sensor for detecting presence or absence is rotatably mounted and operatively connected to the first operating section, and a rotary operating shaft of the differential sensor is operatively connected to the second operating section. As a rotational stroke difference occurs between the first operating section operated by the first drive mechanism and the second operating section operated by the second drive mechanism, the main body and the The rotational operation shaft relatively rotates to put the differential sensor into an operating state, and the first operating section is operated by the first drive mechanism and the second operating section is operated by the second drive mechanism. When there is no rotational stroke difference between the main body and the rotational operation shaft, the main body and the rotational operation shaft rotate in the same direction and the same rotational angle, and the differential sensor is in a non-operational state, differential cancellation that automatically adjusts the difference between the first operation section operation speed by the first drive mechanism and the second operation section operation speed by the second drive mechanism to a state where the operation section is in a detection state with no operation section differential. A control means is provided, and the first drive mechanism and the second drive mechanism are controlled by the speed change control means.
Control switching means is provided for automatically executing speed difference adjustment control by the differential cancellation control means only when the drive mechanism is operated. The functions and effects thereof are as follows.

[For production]

When changing the running direction of the aircraft, the differential cancellation control means does not operate due to the control switching means, and the speed difference between the first continuously variable transmission and the second continuously variable transmission is realized and the machine is operated. This makes it possible to become more active in gymnastics.

When changing the aircraft running speed, the control switching means enables the differential cancellation control means to operate, and the difference between the rotational stroke of the first operation section and the rotational stroke of the second operation section is changed. The differential cancellation control means automatically adjusts the operating speed of the operating section based on information from the differential sensor so that the speed does not occur at all or very often. In either case, the speeds of the first and second continuously variable transmissions change in a state that matches as much as possible.

In order to perform speed governing control by the differential cancellation control means, a pair of stroke sensors are provided to separately detect the strokes of the first and second operation parts, and the detection result by one stroke sensor and the detection result by the other stroke sensor are separated. If the configuration is such that the presence or absence of a stroke difference and the direction of corrective control are detected by comparing the two and determining the magnitude relationship, a pair of sensors for the first transmission side and the second transmission side are required. At the same time, a signal processing means for comparing and determining the detection results by the sensor is required. On the other hand, the main body of the differential sensor is interlocked and connected to the first operation part so as to rotate in conjunction with the first operation part, and the rotational operation shaft of the differential sensor is interlocked and connected to the second operation part so as to rotate in conjunction with the second operation part. If the differential sensor is configured so that it is operated by the rotational stroke difference between the first operating section and the second operating section, the number of required sensors will be halved, and the differential sensor will output a signal to detect no differential. All that is required is to process a signal so that the differential cancellation control means automatically operates in a state where the differential resolution is achieved. In addition, in order to be able to control the speed of the first and second continuously variable transmissions over a long period of time, the first
Even if the rotational stroke required to operate the second operation section is relatively large, the main body of the differential sensor and the rotational operation shaft rotate in conjunction over the entire rotational stroke, making it possible to detect the presence or absence of a differential. become able to.

〔Effect of the invention〕

Because of the automatic speed regulating control by the differential cancellation control means, the traveling speed can be changed while preventing the aircraft from skewing due to the drive speed difference between the left and right traveling devices, making it possible to perform work safely.

Furthermore, the control structure can be simplified in terms of the differential detection configuration, and the range of possible speed changes can be made relatively large, which is economically advantageous, and speed adjustment can be made over a wide range.

〔Example〕

Next, examples will be shown.

As shown in Figures 6 and 7, the engine (
A flail mower device (2) is connected to the front part of a crawler-type traveling body having a lift cylinder (C) so that it can be raised and lowered via a link mechanism (1) that is raised and lowered by a lift cylinder (C), and a The traveling aircraft is equipped with a control mechanism (not shown) that receives operation signals from the control device (3) through the antenna (4) and automatically performs travel and work control based on the input signals. This is a mower that is capable of

As shown in Figure 5, the engine (E) is connected to the transmission mechanism (■).
The variable displacement type first and second hydraulic pumps (PI) and (P2) are interlocked so that the driving force is transmitted through The first hydraulic motor (M1) connected via the drive circuit (6a) with the left and right crawler type traveling devices (7), (7
), and is connected to a second hydraulic pump (P2) via a drive circuit (6b) having a refueling stop valve (5). the crawler drive wheels (
By interlocking with 7a), the aircraft can run.

That is, the rotational output of the engine (E) is transmitted by the first hydraulic pump (P2) and the first hydraulic motor (M1) to drive one of the traveling devices (7), and as shown in FIG. Swash plate operation shaft (8a) of the first hydraulic pump (P1)
The swash plate angle is changed by rotating the first operation part (9a), which is formed by attaching a swinging member so as to be integrally rotatable with the hydraulic type. This constitutes the first continuously variable transmission (T1). The rotational output of the engine (E) is transmitted by the second hydraulic pump (P2) and the second hydraulic motor (M2) to drive the other traveling device (7), and as shown in FIG. Gotoku Part 2
The swash plate angle can be changed by rotating the second operation part (9b), which is formed by integrally rotatably attaching a swinging member to the swash plate operation shaft (8b) of the hydraulic pump (P2), and the swash plate angle can be changed between the neutral position and the swash plate angle. A hydraulic second continuously variable transmission (T2) is configured to switch between the forward and reverse sides.

As shown in FIG. 1st
In addition to being operated by an electric motor (m2), the second operation part (9b) is connected to a link type interlocking mechanism (10), and a mechanism (1) that exchanges the rotational force of the second DC electric motor (m2) with push/pull force.
1) and is configured to be operated by the second electric motor (m2) via the second electric motor (m2). And, as shown in Figure 4,
The first drive circuit (DI) for controlling the first electric motor (m1)
), a second drive circuit for controlling the second electric motor (m2) (
D2) A speed change control means (12) and a steering control means (
13), and these control means (12) and (13) include a first speed sensor (S1) that detects the driving direction and speed of the first continuously variable transmission (T1), and a second continuously variable transmission (T1). A second speed sensor (S2) that detects the driving direction and speed of the gear transmission (T2), and a receiving device (
By linking the control device (3)
) enables radio control.

That is, when the forward/reverse stick (15) of the control device (3) is operated to swing from the neutral position (N) to the forward side (F) or reverse side (R), the control device automatically moves along with this stick operation. (3) is configured to set the driving direction and speed of the first and second continuously variable transmissions (TI) and (T2), and output a running signal instructing the set driving direction and set speed. It is. This speed setting is configured such that the larger the swing stroke of the forward/reverse stick (15) from the neutral position (N), the higher the set speed. Then, as the receiving device (14) receives the driving signal from the control device (3), the speed change control means (12) automatically transfers the set drive direction and set speed by the control device (3) to the receiving device (14). ), and the detected direction and detected speed by the first speed sensor (S1) and the second speed sensor (S2) are equal or almost equal to the direction and speed set by the control device (3). By outputting a signal to control the continuously variable transmission (T1) or (T2) to the first and second drive circuits (DI) and (D2), the first and second continuously variable transmissions (TI),
The first and second electric motors (+r++
), (m2) are configured to operate automatically. In other words, the forward/reverse stay (15) is at the neutral position (
When operated from N), the aircraft will automatically move straight forward or backward as determined by the stick rocking direction at a speed determined by the stick rocking stroke.
The speed change control means (12) controls the first and second continuously variable transmissions (T
I), (T2>) are driven in the same driving direction and appearance speed.

Then, the steering stick (1) of the control device (3)
6) from the neutral position (N) to the left steering side (L) or the right steering side (R), the control device (3) automatically moves to the first stepless position along with this stick operation. Speed difference that should appear between the transmission (T1) and the second continuously variable transmission (T2), and the first and second continuously variable transmission (TI)
, (T2) to be set to the high speed side, and outputs a steering signal instructing the set speed difference and the set high speed side. This speed relationship setting is configured such that the larger the operating stroke of the steering stick (16) from the neutral position (N), the larger the speed difference and the smaller the turning radius. Then, as the receiving device (14) receives the steering signal from the control device (3), the steering control means (13) automatically receives the set speed difference and the set high speed side by the control device (3). Input via the device (14) as well as the detected speed by the first speed sensor (S1) and the second speed sensor (S2)
The first and second continuously variable transmissions (TI) and (T2) are controlled so that the result obtained by comparing and determining the speed detected by the control device (3) is equal to or almost equal to the set speed and the set high speed side by the control device (3). By outputting signals to the first and second drive circuits (DI) and (D2), the output speed of the first continuously variable transmission (T1) and the output speed of the second continuously variable transmission (T2) are adjusted. The first and second electric motors (m2), (
m2) is configured to operate automatically. In other words, as the steering stick (15) is operated from the neutral position (N), the aircraft automatically turns to the left or right side determined by the stick rocking direction with a turning radius determined by the stick rocking stroke. , the steering control means (13) comprises first and second continuously variable transmissions (TI);
(T2> is operated to create a drive speed difference.

The first speed sensor (S1) and the second speed sensor (S2) are composed of rotary potentiometers, as shown in FIGS. 1 to 3, and are attached to the swash plate via a plate (17a) or (17b) It is configured to be supported by the operating shaft (8a) or (8b), and is mounted on the plate (17a) and (1
7b) is fixed so as not to move by the action of a connecting member (18) which connects the swash plate operating shaft (8a) or (8b) so as not to rotate. And the speed sensor (
S1) and (S2) rotation operation shaft (19a) or (1
The gear (20a) or (20b) attached to the boss part of the operation part (9a) or (9b) so as to be able to rotate together with the fan-shaped gear (21a) or (20b) attached to the boss part of the operating part (9a) or (9b)
21b), the first speed sensor (S
1) is linked to the first operation part (9a) so as to enable predetermined detection of the first continuously variable transmission (T1), and the second speed sensor (S2) is linked to the predetermined detection of the second continuously variable transmission (T2). It is linked to the second operation part (9b) so that the detection of

As shown in Figure 2, the main body (26) of the differential sensor (S3) consisting of a rotary potentiometer is connected to the connecting bolt (27).
, the first gear member (28), the second gear member (29), and the support member (30).
17b), the members (17a), (17b), (
30) and so on. The first gear member (28) and the second gear member (29) are
In addition, the second gear member (29) and the support member (30) are relative to each other around the axis (X) of the rotation operation shaft (31) of the differential sensor (S3) due to the fitting structure between them. The first gear member (28) is configured to rotate and rotates together with the main body (26) by the action of the connecting bolt (27).
By engaging the sector gear (21a), the main body (26) of the differential sensor (S3) is connected to the swash plate operation shaft (8a).
and (8b), the first operation part (9a
) is interlocked and connected to the first operating section (9a) so as to rotate around the axis (X) in conjunction with the rotation of the first operating section (9a). and,
The rotation operation shaft (31) of the differential sensor (S2) and the second gear member (29) are configured to rotate together by the action of the interlocking member (32), and the second gear member (29) is configured to rotate together with the second gear member (29). By engaging the sector gear (21b) of the second operating section (9b), the rotary operating shaft (31) is interlocked and connected to the second operating section (9b), thereby connecting it to the first operating section (9a). The differential sensor (S3 ).

That is, the swash plate operation shafts (8a) and (8b), the operation section (
9a) and (9b), fan-shaped gears (21a) and (21b)
), etc., the first continuously variable transmission (T1) and the second continuously variable transmission (T2) may be on the same side both in the forward and reverse directions and in the acceleration/deceleration side. When switching, the main body (26) of the differential sensor (S3) and the rotary operation shaft (3
1) rotates in the same direction, and the first continuously variable transmission (T1)
When the speed change width of the second continuously variable transmission (T2) is the same, the rotation angle of the main body (26) and the rotation angle of the rotary operation shaft (31) are the same. be. For this reason, as a rotational stroke difference occurs between the first operating part (9a) and the second operating part (9b), the operation is performed based on the stroke difference and the operating force of the electric motors (m1) and (m2). Due to the partial operation, the main body (26) and the rotary operation shaft (31) rotate relative to each other, and the differential sensor (S3) becomes operated, and at this time, the differential sensor (S3) is activated. Based on the result of comparing and determining the resistance value to be output with a preset reference resistance value, the speed difference between the continuously variable transmissions (T1) and (T2), and which continuously variable transmissions (T1) or ( It is determined whether T2) is on the high speed side. When there is no rotational stroke difference between the first operating section (9a) and the second operating section (9b), the main body (26) of the differential sensor (S3)
) and the rotary operation shaft (31) rotate in the same direction and through the same rotation angle, and the differential sensor (S3) becomes non-operational.
Knowing that the resistance value appearing from the differential sensor (S3) is the reference resistance value, it is determined that there is no speed difference between the continuously variable transmission (TI) and (T2).

As shown in FIG. 4, the differential sensor (S3) is connected to the first drive circuit (D1) via the differential cancellation control means (24).
In addition, the differential canceling means (24) is linked with the control switching means (25) to prevent skewing when the speed change control means (12) performs speed increase and deceleration control.

That is, when the speed change control means (12) performs the increase/deceleration control, the control switching means (25) changes the differential cancellation control means (24) based on information from the speed change control means (12).
The device is configured to automatically switch to the operating state. When the differential cancellation control means (24) is activated, it automatically increases or decreases the rotational speed of the first electric motor (m1) based on the detection result by the differential sensor (S3). By outputting a signal to be maintained at the current state to the first drive circuit (D1), the differential sensor (S3)
automatically adjusts the difference between the first operation part operation speed by the first electric motor (m1) and the second operation part operation speed by the second electric motor (m2) so that the operation part is in a detection state with no operation part differential. The output speed by the first continuously variable transmission (T1) and the second continuously variable transmission are
It is configured to perform speed difference adjustment control to eliminate the difference between the speed and the speed exhibited by the continuously variable transmission (T2). When the speed change control means (12) does not perform the increase/deceleration control, the control switching means (25) controls the differential cancellation control means (24) based on the information from the speed change control means (12).
) is automatically switched to a non-operating state so that the steering control means (13) can perform speed difference appearance control.

The hydraulic motor (M3) shown in FIG. 5 is for driving the flail mower device (2).

[Another example]

Instead of the crawler traveling device (7), a multi-wheel traveling device in which a plurality of wheels are arranged in the longitudinal direction of the aircraft may be used.
7).

Instead of the first and second electric motors (m2) and (m2), various actuators such as hydraulic cylinders may be adopted and implemented, and these can be replaced with the first drive mechanism (m1) or the second drive mechanism ( m2).

In addition to the radio-controlled type, the present invention can also be applied to riding-type and walking-type work vehicles. Therefore, the forward and backward stick (
15) is referred to as a speed change operation means (15), and the steering stick (16) is referred to as a steering control means (16).

Note that although reference numerals are written in the claims section for convenience of comparison with the drawings, the present invention is not limited to the structure of the attached drawings by such entry.

[Brief explanation of drawings]

The drawings show an embodiment of the traveling control device for a working vehicle according to the present invention, in which FIG. 1 is a partially cutaway side view of the gear shift operation structure, and FIG. 2 is a partially cutaway plan view of the differential sensor installation section. , Figure 3 is the first
Figure 4 is a block diagram of the traveling control system, Figure 5 is a hydraulic circuit diagram, Figure 6 is a side view of the entire mower, and Figure 7 is a plan view of the entire mower. be. FIGS. 8 and 9 are explanatory diagrams of problems in the conventional device. 7)...Traveling device, (9a)--first operation section,
(9b...Second operating section, (I2)...Shift control means, (13...Steering control means, (15)
- Speed change operation means, (16... Steering operation means, (18) - River - Operation member, (24... Differential cancellation control means, (25) - Mountain ...control switching means, (
26)...Main body, (31)...River/rotation operation shaft, (T2)...First continuously variable transmission, (I2) Town, Second continuously variable transmission, (m2)...First drive mechanism, (m2)・River...Second drive mechanism, (S2)・Mountain・
・Differential sensor.

Claims (1)

[Claims] A hydraulic first continuously variable transmission (T_1) and a second continuously variable transmission (T_1) that drive the left and right traveling devices (7), (7) separately.
_2) is provided, and the first continuously variable transmission (T_1) is provided with a
a first drive mechanism (m) that separately operates the operating section (9a) and the second operating section (9b) of the second continuously variable transmission (T_2);
_1) and a second drive mechanism (m_2), and the speeds appearing by the first continuously variable transmission (T_1) and the second continuously variable transmission (T_2) are controlled by the speed change operation means (15).
) The first drive mechanism (m_1) and the second drive mechanism (m_1)
_2), the speed change control means (12) automatically operates the speed change control means (12), which controls the difference between the speed exhibited by the first continuously variable transmission (T_1) and the speed developed by the second continuously variable transmission (T_2). A steering control means (13) is provided for automatically operating the first drive mechanism (m_1) and the second drive mechanism (m_2) to a state where the speed difference is equal to or approximately equal to a speed difference set by the direction operation means (16). A travel control device for a working vehicle, comprising a differential sensor (S_3) that detects the presence or absence of a difference between the rotation stroke of the first operation part (9a) and the rotation stroke of the second operation part (9b). The main body (26) is rotatably attached and operatively connected to the first operating portion (9a), and
The rotational operation shaft (31) of the differential sensor (S_3) is interlocked with the second operation part (9b), and the first operation part (9a) is operated by the first drive mechanism (m_1).
As a rotational stroke difference occurs between the main body (26) and the second operating portion (9b) operated by the second drive mechanism (m_2), the main body (26) and the rotational operating shaft are operated in order to operate the operating portion. (31) rotates relative to the differential sensor (S
_3) is in the operating state, and the first drive mechanism (m
_1) and the second operating part (9a) operated by the second drive mechanism (m_2).
When there is no rotational stroke difference with the operating portion (9b), the main body (26) and the rotational operation shaft (31) rotate in the same direction and at the same rotational angle, and the differential sensor (S_3)
is configured such that the differential sensor (S_3) is in a non-operating state, and the operating speed of the first operating part by the first drive mechanism (m_1) and the second The second drive mechanism (m_2)
A differential cancellation control means (24) is provided to automatically adjust the difference between the speed of operation of the operating section and
_1) and a work in which a control switching means (25) is provided that automatically executes the speed difference adjustment control by the differential cancellation control means (24) only in a state where the second drive mechanism (m_2) is operated. Car travel control device.