JPH02146373A - Transmission for vehicle - Google Patents

Abstract

PURPOSE:To improve safety, by detecting the change of the rotation ratio of a follower shaft against a motive shaft before and after a main clutch cut off operation, and prohibiting a speed shift operation in the case of the decision of no change having been made. CONSTITUTION:The detection values of respective stroke sensors 22-25 and rotation detectors 18, 19 are read into a controller 20 during an engine 2 rotation action, and the rotation ratio a of a follower shaft 6 against a motive shaft 5 is calculated. When a program whose purpose is to cut off a main clutch 3, is carried out, again a rotation ratio b is processed in operation, and whether or not there is a change in rotation ratios a, b, is decided by means of the controller 20, and in the case of a and b being equal, the decision of abnormality is made, and a speed shift operation is prohibited and at the same time, abnormality is indicated at an indicator. When change is noticed, the decision of normality is made, and the speed shift operation is conducted, and a program that connects the main clutch 3 is carried out. As a result, safety is secured, and the breakage of an apparatus can be prevented, too.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] This invention disengages the main clutch when the shift lever or push button is operated to perform a shift operation.

The present invention relates to a vehicle transmission in which a main clutch is automatically connected after a gear shift.

[Prior Art] Conventionally, this type of transmission device used in tractors, etc. has at least a mechanical main transmission with three forward speeds and one reverse speed, an auxiliary transmission with two high and low speed speeds, and a plurality of mechanical transmissions for switching between them. The shifter consists of an actuator that moves the shifter using hydraulic or pneumatic force, and when the shift push button etc. is operated to shift gears, the main clutch is first disengaged, and then the main clutch is reconnected after shifting. The configuration was as follows.

[Problems to be Solved by the Invention] By the way, in such a conventional device, the speed change command is controlled by the CPU! When the engine is moved out of position A, the main clutch is first disengaged, a gear change operation is performed, and after the gear change, a program is executed that connects the main clutch again; it does not determine whether or not the main clutch has actually been disengaged. Because the main clutch was seize up, rusted, etc. and would not shut off, if a gear shift command was issued, the gear shift operation would be forced, resulting in equipment damage or the aircraft going out of control. was there.

[Means for Solving the Problems] The present invention is proposed in view of the above problems, and takes the following technical measures. That is, engine 2
A main clutch 3 is provided between the and the mechanical transmission 4.8,
In a vehicle transmission device configured such that when the transmission device 4.8 is operated to change gears, the main clutch 3 is first disengaged to perform a gear change, and then the main clutch 3 is connected again after the gear change. The driving shaft 5 located before and after the
Detectors 18 and 19 are provided to detect the rotation speed of the driven shaft 6 and the ratio a of the rotation speed of the driven shaft 6 to the driving shaft 5 before the main clutch 3 is disengaged, and after the main clutch 3 is disengaged. Further, means is provided for calculating the ratio of the rotational speed of the driven shaft 6 to the driving shaft 5.

A vehicle characterized in that a means is provided for determining whether or not there is a change in the ratio before and after the third disengagement operation of the main clutch, and if there is no change in the ratio, the shift operation after the third disengagement operation of the main clutch is prohibited. This is the configuration of the transmission.

[Action and effect] When a shift command is issued from the control device 20, first.

The rotational speeds of the driving shaft 5 and driven shaft 6 before the main clutch 3 is disengaged are determined, and the rotation ratio a of the driven shaft 6 to the driving shaft 5 is calculated. The ratio of the rotation speed of the driven shaft 6 is calculated. The determining means then determines whether there is a change in these ratios before and after the main clutch 3 is disengaged. and,
If there is a change in the rotation ratio before and after the main clutch 3 is disengaged, it is recognized that the main clutch 3 is working normally and the gear change operation is performed, and if there is no change, the gear change operation is prohibited.

As described above, in this invention, as the main clutch 3 is disengaged, it is detected whether or not there has been a change in the rotation ratio of the driven shaft 6 to the driving shaft 5 between before and after the main clutch 3 is disengaged. This makes it possible to detect abnormal conditions such as clutch plate sticking, and if an abnormality is determined, shifting operations are prohibited, further improving safety. At this time, safety can be further enhanced by configuring the system to notify the operator of abnormal conditions using a monitor or the like.

[Example] Hereinafter, the present invention will be described in detail based on the drawings.

First, to explain the structure, reference numeral 1 denotes a tractor, and an engine 2 is mounted on the front of the machine body.The rotational power of the engine 2 is transmitted to a mechanical main transmission 4 via a main clutch 3. 5 is a driving shaft directly connected to the engine 2, and 6 is a driven shaft disposed downstream of the main clutch 3. The rotational power decelerated by the main transmission 4 is further transmitted to the auxiliary transmission 8, and the rotational power decelerated here is transmitted to the rear wheel axle 10 via the rear wheel differential device 9.

The main transmission 4 is capable of shifting into three forward speeds and one reverse speed;
The Fit 8 auxiliary transmission is capable of two speeds, both of which are synchromesh type gear mechanisms. When the push button switch 14a of the shift operation panel 12 is pressed for both the main transmission 4 and the auxiliary transmission 8, the main clutch 3 is first disengaged, and the hydraulic actuator 15 for shifting is released.
a... is the shifter of the main and sub-transmission device 4.8 (not shown)
A gear shifting operation is performed by moving the .

Detectors 18 and 19 are provided near the driving shaft 5 and driven shaft 6 to detect the rotation speed of each shaft.
8.19 is connected to a control device surface 20 which will be described later. This control device 20 is provided with an arithmetic processing unit that calculates the ratio of the rotation speed of the driven shaft 6 to the driving shaft 5, and further calculates the rotation ratio a before the main clutch 3 is disengaged, and the rotation ratio a when the main clutch 3 is disengaged. Means is provided for comparing subsequent rotation speed ratios and determining whether there has been a variation between those ratios.

Figure 2 shows the relationship between the power transmission system and the control device, Figure 3 shows the relationship between the power transmission system and the control device.
The figure is a block diagram of this control system. 21 is a hydraulic actuator for turning on and off the main clutch 3, and 22 is a stroke sensor that detects the amount of movement of the actuator 21. 23 to 25 are stroke sensors for detecting the positions of actuators 15a, 15b, and 15c that slide gears for gear change, 23 is for forward 1st speed and reverse of the main transmission 4, 24 is for forward 2nd speed, 3 25 is a stroke sensor for 1.2 speed of the sub-transmission device 8. These are connected to the control device 20 via an A/D converter 32. 33 to 39 are the actuators 22, 15a;
, 15b, 15c, and when these solenoid valves are energized by a command from the control device 20, the corresponding actuators are activated and a speed change is performed. Note that reference numeral 42 is a display device that displays the gear shift position, and 43 is a main clutch pedal.

Next, the operation of this control device will be explained based on the flowchart of FIG.

While the engine 2 is rotating, each stroke sensor 22
The detected values of 25 to 25 and the detected values of the rotation detectors 18 and 19 are read into the control bag v120 (step ■), and it is determined whether there is a shift request (step ■), that is,
Push button switches 14a and 14 for main and sub-transmission devices 4 and 8
b, . . . are operated appropriately, the rotation ratio a of the driven shaft 6 to the driving shaft 5 is calculated from the rotational speed of the driving shaft 5 and the driven shaft 6, and a program for disengaging the main clutch 3 is executed. (Step ■) After that, the rotation ratio of the driven shaft 6 to the driving shaft 5 is calculated again. (Step ■) Main clutch 3
A determining unit in the control device 20 determines whether there is a change in the rotation ratios a and b before and after the operation, and if the values of a and b are equal after the determination.

It is determined that there is an abnormality, and the speed change operation is prohibited, and the abnormality status is displayed on the display device 42 (step ■■). After the determination, if it is found that the rotation ratio after the main clutch 3 disengagement operation has changed from the ratio a before the main clutch 3 disengagement, it is determined that it is normal, and the speed change operation is performed and the main clutch 3 (Program ■
0).

In this manner, in this embodiment, the rotational speeds of the driving shaft 5 directly connected to the engine 2 and the driven shaft 6 disposed downstream of the transmission of the main clutch 3 are detected.

Calculate the rotation ratio a of the driven shaft 6 to the drive shaft 5 before the main clutch 3 is disengaged, and the rotation ratio a of the driven shaft 6 to the drive shaft 5 after the main clutch 3 is disengaged,
A determining means built into the control device 20 determines whether a change has occurred between the ratios a and b, and if there is no change, a warning is given to the operator using a display device or the like.

It is safe because it prohibits the traveling speed of the tractor 1 from being changed, and damage to the 1 equipment can be prevented6.

[Brief explanation of the drawing]

The figures show an embodiment of the present invention, in which Fig. 1 is an overall side view, Fig. 2 is a diagram explaining the relationship between the power transmission system and the control device, Fig. 3 is a block diagram, and Fig. 4 is a flowchart. . Tractor engine Main clutch Main transmission Driving shaft Driven shaft Sub-transmission Rotation speed detector

Claims (1)

[Claims] 1) A main clutch 3 is provided between the engine 2 and the mechanical transmissions 4, 8, and when the transmissions 4, 8 are operated to change gears, the main clutch 3 is first disengaged and the gears are changed, and then after the gears are changed, the main clutch 3 is disengaged again. In a vehicle transmission configured to connect a main clutch 3, a detector 1 detects the rotational speed of a driving shaft 5 and a driven shaft 6 located before and after the main clutch 3.
8 and 19 are provided to determine the ratio a of the rotational speed of the driven shaft 6 to the driving shaft 5 before the main clutch 3 is disengaged, and the main clutch 3
Means for calculating the ratio b of the rotational speed of the driven shaft 6 to the driving shaft 5 after the main clutch 3 is disengaged is provided, and further provided is a means for determining whether or not there is a change in the ratio before and after the main clutch 3 is disengaged. A vehicle transmission device, characterized in that, if there is no change in the ratio, a gear shift operation after three main clutches is disengaged is prohibited.