JPH0355352B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is an engine-driven hydromechanical transmission and steering device that has one input shaft and two output shafts and is mainly used for tracked vehicles. This relates to a control method, and its purpose is to provide a super pivot turning control method that can reliably perform super pivot turning operations at any speed and improve the maneuverability of the vehicle. It is about providing.

Embodiments of the present invention will be described below with reference to the drawings.

In the figure, 1 is one input shaft 3 connected to the engine 2.
and a mechanical transmission having two (left and right) output shafts 4 and 5, 6 and 7 are 2 driven by the engine 2.
The two (left and right) hydraulic pumps, 8 and 9, are hydraulic motors driven by the discharge oil of the respective hydraulic pumps 6 and 7, and the output shafts of both motors 8 and 9 are connected to the transmission 1. By controlling the hydraulic motors 8 and 9, the transmission 1 is configured to be continuously variable within each speed stage. The transmission 1 has a clutch A for 1st speed, a clutch B for 2nd speed, a clutch C for 3rd speed, and a clutch D for 4th speed, and by selectively operating each of them with hydraulic pressure, the output shafts 4 and 5 are controlled. The rotational speed is changed from 1st speed to 4th speed.

11 is a throttle position detector that detects the throttle position for controlling the rotational speed of the engine 2 and takes out a signal a from this, and 12 detects a turning angle of a steering wheel for turning the vehicle and takes out a signal b from this. 13 is a change lever position detector that detects the four positions of the change lever: forward, reverse, neutral, and super turning, and outputs a signal c corresponding to each position. 14 is a change lever position detector that detects the engine brake. 15 is an engine rotation speed detector that takes out an engine rotation speed signal n _E based on the actual engine rotation speed; 16 and 17 are rotation speed signals n _n1 of each hydraulic motor 8 and 9; ,n Motor rotation speed detector to take out _n2 ,
18, 19, 20, and 21 are hydraulic switches that detect the hydraulic pressure of the clutches A to D for the first to fourth speeds and take out the respective signals e, f, g, h; 22,
23, 24, 25 are the clutches A for 1st to 4th speeds.
The clutch changeover switches 26 and 27 that control the pumps 6 and 7 are actuators for controlling the discharge amount of both the pumps 6 and 7. 28 is a control logic circuit;
This circuit 28 receives each of the above-mentioned signals a to h and n _E , n _n1 ,
By inputting n _n2 , the discharge amount control actuator 2 of both pumps 6 and 7 responds to this input signal.
6 and 27, and signals k, l, m, and n are output to each clutch changeover switch 22-25.

Specific examples of the actions of the method of the present invention and the control logic circuits for each action will be shown below.

By rotating the left and right output shafts 4 and 5 at the same rotation speed in opposite directions, the transmission and steering gear can make the vehicle turn on the spot, improving the maneuverability of the vehicle. can. In the embodiment shown in FIG. 1, this super turn is possible when the first gear clutch A is engaged or when neither clutch is engaged, but when neither clutch is engaged. If the magnitude of the load torque on the left and right output shafts 4, 5 changes, it may not be possible to perform a super-turn. Therefore, in this embodiment, an example will be shown in which the first speed clutch A is engaged to perform a super turning.

Next, a specific control method will be explained with reference to FIG.

When the change lever is at the super pivot turning position, the super pivot signal c from the change lever position detector 13 enters the control logic circuit, and the signal k is output to the 1st gear selector switch 22 to switch the 1st gear clutch. A is turned on, and at the same time, a signal e is output from the first speed clutch hydraulic switch 18. On the other hand, the throttle position signal a at that time is input from the throttle position detector 11 to the engine speed setting device 30. This engine speed setting device 30 stores the relationship between the throttle position and the target engine speed (N _E ), and the throttle position signal a
is input, the engine rotation speed signal n E from the engine rotation speed detector 15 that detects the signal N _E of the target engine rotation speed (N _E ) at this time and the actual engine rotation speed (n _E ) _is input. are compared and calculated by the comparison calculator 31, and an engine rotation speed difference signal _I1 is outputted from this. The above actual engine speed (n _E )
varies depending on the load at that time. This engine speed difference signal I ₁ is then input to the arithmetic unit 32 . The arithmetic unit 32 receives a super turn signal c from the change lever position detector 13, a signal e from the first gear clutch hydraulic switch 18, and a steering wheel angle signal b from the steering wheel angle detector 12. is input. And here each input signal I ₁ ,
b, c, and e are compared and calculated, and signals i and j such that the engine speed difference signal _I1 indicates the direction in which the vehicle turns to the left or right are sent to the hydraulic pump via adders 71 and 72. The discharge amount control actuators 26 and 27 are outputted to the discharge amount control actuators 6 and 7. As a result, the engine speed is the target speed (N _E ) corresponding to the throttle position.
The hydraulic motors 8 and 9 are controlled so that When the value θ of the steering wheel angle signal b is θ>θ ₀ , the vehicle is turned to the right, for example, and when θ<−θ ₀ , the vehicle is turned to the left, for example. Note that θ ₀ is the play angle of the steering wheel, and when |θ|≦θ ₀ , a signal similar to the neutral control is added to the signals i and j within the handle play range. The adders 71 and 72 add an engine speed difference signal +I ₁ or - to the currently output signals i and j.
It is an arithmetic unit that adds I ₁ .

The present invention is as described above, and when the change lever is at the super swing position, the first gear clutch A is turned ON via the control logic circuit 28 by the super swing signal c from the change lever position detector 13. Also, an engine speed difference signal _I1 is obtained from the difference between the target engine speed (N _E ) and the actual engine speed (n _E ) with respect to the throttle position, and this engine speed difference signal _I1 and the change lever A super turning signal c from the position detector 13, a signal e from the first gear clutch hydraulic switch 18, a steering wheel angle signal b from the steering wheel angle detector 12, and a signal from the change lever position detector 13. The engine rotation speed difference signal _I1 is compared with the super turning signal c, and the hydraulic pump 6,
Since it is added to the discharge amount control signals i and j of No. 7 to perform a super pivot turn, the super pivot turning operation can be performed reliably even at the first speed stage, and the maneuverability of the vehicle can be improved. can. Further, according to the present invention,
Super pivot turns are always performed with optimal engine output.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a control system diagram, and FIG. 2 is an explanatory diagram showing an embodiment of the main part of the present invention. 1 is the transmission, 2 is the engine, 3 is the input shaft,
4 and 5 are output shafts, 6 and 7 are hydraulic pumps, 11 is a throttle position detector, 12 is a handle angle detector,
13 is a change lever position detector, 15 is an engine rotation speed detector, and 18 is a hydraulic switch.

Claims (1)

[Claims] 1 One input shaft 3 connected to the engine 2, left and right output shafts 4 and 5, and a multi-speed hydraulic clutch A
-D, a mechanical transmission 1, left and right hydraulic pumps 6, 7 driven by the engine 2, and left and right hydraulic motors 8, 9 driven by the oil discharged from these pumps.
The output shafts of the hydraulic motors 8 and 9 are connected to the transmission 1, and the transmission 1 is controlled by the hydraulic motors 8 and 9 so that the transmission 1 can be changed steplessly at each speed stage. In the transmission and steering gear, when the change lever is at the super pivot turning position, the first gear clutch A is turned ON via the control logic circuit 28 in response to the super pivot signal c from the change lever position detector 13; In addition, an engine speed difference signal I ₁ is obtained from the difference between the target engine speed (N _E ) and the actual engine speed (n _E ) with respect to the throttle position.
This engine speed difference signal I ₁ and the super turning signal c from the change lever position detector 13
, the signal e from the hydraulic switch 18 of the first gear clutch, the steering wheel angle signal b from the steering wheel angle detector 12, and the super position signal c from the change lever position detector 13 are compared and calculated. A hydromechanical transmission system characterized in that an engine speed difference signal _I1 is added to discharge amount control signals i and j of hydraulic pumps 6 and 7 in a direction in which the vehicle makes a sharp turn to the left or right. A method for controlling the steering aircraft's super-turning position.