JPH0522685Y2 - - Google Patents

Description

[Detailed explanation of the idea] (Industrial application field) This invention relates to improvements in automatic transmissions.

(Prior Art) In recent years, in order to reduce driver fatigue, an increasing number of vehicles are equipped with automatic transmissions that automatically change gears by interposing a torque converter between the engine and the transmission. Since the torque converter is a fluid coupling, the output transmission efficiency is inevitably lower than that of a mechanical clutch, which is disadvantageous in terms of improving fuel efficiency.

Therefore, in order to improve not only ease of operation but also fuel efficiency, we used a conventional transmission and mechanical clutch, and instead of having the driver operate the clutch or transmission, they were automatically controlled by electronic control. The applicant of the present invention has proposed an automatic transmission device in which a gear shifting operation is performed automatically (for example, Japanese Utility Model Application No. 62-20926 and Japanese Utility Model Application Publication No. 62-23134).

FIG. 6 is a flowchart showing the control operation, and the basic operation is the same as the operation of an automatic transmission using a torque converter.

In addition, the transmission employs a synchronized mesh mechanism that quickly matches the rotational speeds of the gears that engage, but basically the gears that engage are aligned within a predetermined relative rotational speed difference range (synchronizable range). If they can be accommodated, they can be meshed without causing gear noise, etc., even without a synchronized mesh mechanism.

Therefore, in order to reduce costs, this device omit the synchronized mesh mechanism, which has a complicated structure, and detects the rotational speed of the gears to be meshed, and sets the gears when the two reach the synchronized range (synchronized range). I'm letting it happen.

For example, when shifting up, as shown in Figure 7, if the vehicle speed V increases due to acceleration and it is determined that a shift is necessary, the control lever of the fuel injection pump is returned to the no-load position at steps 20 to 22. At the same time, disengage the mechanical clutch and set the transmission to the neutral position. Incidentally, FIG. 7 is a flowchart showing the operation of the shift-up control performed in step 8 of FIG. 6.

Thereafter, at step 23, the clutch is immediately engaged. This is because in manual shifting, the clutch is normally engaged after the gear shift is completed, but during this time the engine speed drops towards idle speed independent of the axle, and if this drop in speed is large, this occurs when the clutch is engaged. Since the reduced engine speed is rapidly raised to the axle side speed, it acts as a large load on the drive system, causing a gear shift shock. Therefore, in order to reduce this shift shock and further shorten the time required for shifting, the clutch is connected to the engine output shaft except when the transmission is set in the neutral position.

24, the gear rotation speed Ng of the main gear idly rotating on the main shaft is detected, and N decreases to 2.
When Ng≦Nsyc+ΔN at step 5, it is determined that Ng is in the synchro region, and gear setting for meshing the main gear and the main shaft is started, and after the gear setting is completed, the control lever is returned to its original position at step 27.

Here, Nsyc is the rotational speed of the main shaft connected to the axle, and ΔN is the allowable value set as the relative rotational speed difference that can start the shift set operation of the main gear meshing with respect to this Nsyc,
Nsyc+ΔN gives the upper limit of the synchronization area.

For example, when shifting up from 2nd gear to 3rd gear is shown in Figure 8, the synchronization region is shown by the shaded area, and the rotational speed Ng of the main gear, which is disconnected from the main shaft at point A, decreases. Then, gear setting starts at point B, which enters the synchro area.
Synchronous meshing is completed at point C.

(Problem to be solved by the invention) By the way, in such a prior application, the rotational speed Ng of the main gear that is disconnected from the main shaft is
The falling speed (deceleration) of the main shaft (corresponding to the engine rotational speed) varies greatly depending on whether or not the exhaust brake is activated to shorten the time required for shifting, and changes in engine water temperature. Multiple allowable values with different sizes are set for the ΔN, and one of the allowable values is selected depending on changes in engine water temperature and whether or not the exhaust brake is activated to determine the synchronization state. This made it impossible to accurately judge the deceleration of the main gear rotation, and in some cases, there was a possibility that a shift error would occur.

This invention aims to solve these problems.

(Means for solving the problem) FIG. 1 is an overall configuration diagram showing clearly the configuration of this invention.

Reference numeral 33 denotes a gear shift operation control means which determines the driving range in which the gear shift operation of the transmission is to be performed based on signals from the operating state detection means 30 for detecting the operating state of the engine and the vehicle speed detection means 31 for detecting the vehicle speed. , a control signal is output to the governor control means 35, the clutch engagement/disconnection means 37, and the gear shift means 39 to control the speed change operation.

For example, during gear shifting, the governor control means 35 returns the control lever of the fuel injection pump 36 to the no-load position in response to a control signal to the governor control means 35, and the clutch disengagement means 37 returns the control lever of the fuel injection pump 36 to the no-load position in response to a control signal to the clutch disengagement means 37. cut. Also, by the control signal to the gear shift 39,
Gear shift means 39 sets the transmission in a neutral position.

Reference numeral 34 denotes a synchronization determination means, which detects the rotational speed of the deceleration calculation means 29 which calculates the deceleration of the engine rotation during the gear change operation based on the detection signal from the engine rotation detection means 28, the vehicle speed detection means 31, and the main gear. Based on the signal from the gear rotation speed detection means 32, different tolerance values ΔN ₁ , ΔN ₂ . Select the optimum allowable value corresponding to the deceleration of the engine rotation at that time, for example ΔN ₁ , and set the synchronizable region Nsyc.
+ΔN ₁ is set, and when the rotational speed N _g of the main gear falls within this synchronizable region Nsyc+ΔN ₁ , it is determined that synchronization is possible.

When it is determined that synchronization is possible, the shift operation control means 3
3 is a gear shift means 39 and a clutch disconnection means 37
The gear shift and the clutch 38 are connected via the gear shift lever 38, and the control lever is returned to its original position via the governor control means 35 after the gear shift is completed.

(Function) Therefore, when the shift operation range is determined based on the driving state and vehicle speed detection signals, the clutch is disengaged and the transmission is set to the neutral position. The synchronization determining means 34 sets a synchronizable region based on the optimum tolerance value selected according to the calculation result of the deceleration of the engine rotation at that time, and when the main gear rotation Ng enters this synchronizable region. , a gear shift to a predetermined gear and a clutch engagement operation are performed.

Therefore, synchronous meshing between the main gear and the main shaft is always performed at optimal timing.

(Embodiment) FIG. 2 is a schematic diagram showing the mechanical configuration of an embodiment of this invention applied to a diesel engine, and FIG. 3 is a block diagram of the same. In this example, the fuel injection pump 41, mechanical clutch 42, and transmission 43 are provided with various detection means for detecting their operating states and actuators for driving them, and a microcomputer transmits information based on signals from these detection means. A control unit 60 configured therein controls the actuator to realize automatic gear shifting.

First, a means for detecting the operating state is required as a detection means, and this operating state is determined by the engine load,
This can be determined from the position of the select lever, the engagement/disengagement state of the clutch, the actual shift position of the transmission, and the vehicle speed. For this reason,
The accelerator pedal 45 has an accelerator sensor 50 that detects the depression angle (accelerator opening degree) of the accelerator pedal 45 as an engine load.
A selector position sensor that detects the position of a selector lever (selector) 49 is connected to the mechanical clutch 4.
2 has a clutch stroke sensor 54 that detects the stroke amount of the clutch, and a transmission 43 without a synchronized mesh mechanism has a shift position sensor that detects the actual shift position and is connected to the axle via the propeller shaft 44. A main shaft rotation sensor 56 is provided to detect the rotation speed of the main shaft. Note that since the main shaft rotation speed is proportional to the vehicle speed, the main shaft rotation speed sensor 56 functions as a vehicle speed sensor.

In addition, synchronization of the gears to be meshed is achieved by driving the gear shift mechanism when the rotational speed Ng of the main gear idly rotating on the main shaft enters the synchronization range established with respect to the rotational speed Nsyc of the main shaft, so the main gear rotational speed It is necessary to detect Ng. In this case, since the main gear is in synchronous meshing with the countershaft that transmits the engine output, the rotational speed of the countershaft is equal to the rotational speed Ng of the main gear, and therefore the countershaft rotation sensor 57 is provided. Furthermore, as will be described later, in selecting the optimal synchronization area that corresponds to the deceleration of engine rotation during gear shifting operation from among multiple synchronization areas set for main gear rotational speed Ng and main shaft rotational speed Nsyc, I need to detect the rotational speed of the engine,
For this reason, an engine rotation sensor 68 is provided that detects the rotational speed of the engine from the rotational speed of a starter ring attached to the engine flywheel.

Next, for these detection means, the fuel injection pump 41 is an actuator that is controlled by the control unit 60, and the control lever of the fuel injection pump 41 is driven in accordance with the request, and the engine is operated to match the engine rotation with the requested rotation. A governor control device 53 that controls the rotation of the clutch 42
The transmission 43 is provided with a clutch actuator 55 that engages and engages the clutch, and a gear shift actuator 59 that drives the gear shift mechanism and performs a select shift operation.

A control unit 60 that controls these actuators receives detection signals from a synchro determination circuit 62, an engine deceleration calculation circuit 66, an accelerator opening sensor 50, etc. as a driving state detection means, and a main shaft rotation sensor 56 as a vehicle speed detection means. It is comprised of a shift change control circuit 61 that controls the speed change operation via a governor control circuit 63, a transmission control circuit 64, and a clutch engagement control circuit 65 based on a signal from a synchronization determination circuit 62.

Here, the function of the synchronization judgment circuit 62 is the main part of this invention, and the function of the synchronization judgment circuit 62 is the main shaft rotation speed Nsyc.
A plurality of allowable values ΔN ₁ to ΔN ₄ of different sizes are set as the relative rotational speed difference ΔN that allows the shift set operation of the main gear meshing with Based on the signal from the deceleration calculation circuit 66 that calculates the deceleration of the engine rotation during operation, the optimum allowable value, for example ΔN ₁ , is selected according to the deceleration of the engine rotation, and the synchronization possible region (Nsyc+ΔN ₁ ) is selected. is set, and when the rotational speed Ng of the main gear falls within this synchronizable range, it is determined that synchronization is possible.

In addition, in this example, so that only the clutch operation at the time of starting can be performed manually, a clutch pedal switch 67 that detects the depression of the clutch pedal 46 and an accelerator opening degree of the accelerator pedal 45 are used to directly inject fuel. A switching device 69 is provided which communicates with the control lever of the pump 41.

FIG. 4 is a flowchart for explaining the synchronization determination operation performed by the control unit 60, and FIG. 5 is a timing chart for explaining shift-up control.

For example, when the vehicle speed increases due to acceleration and it is determined that a shift is necessary, the control lever of the fuel injection pump is returned to the no-load position, the mechanical clutch is simultaneously disengaged, and the transmission is set to the neutral position. These operations are detected in steps 71 to 74, that is, when the clutch pedal switch 67 is OFF (when the clutch pedal 46 is not depressed), the shift lever 49 is shifted to a position other than neutral, and the transmission 43 is connected. is set to neutral by simultaneous operation of the shift valve of the gear shift actuator 59, and when the clutch 42 has also been stroked from the half-clutch point to the engagement side, a timer in the deceleration calculation circuit 66 is started (step 75). By connecting the clutch 42 after the transmission 43 is set to neutral, the engine rotation, that is, the main gear rotation, decreases toward idle rotation regardless of the axle, and during this time, the exhaust brake is driven as necessary.

After confirming that the timer has started, first select the maximum allowable value ΔN ₁ from multiple allowable values ΔN ₁ to _{ΔN 4} (ΔN ₁ > ΔN ₂ > ΔN ₃ > ΔN ₄ ) and set the synchronizable region (Nsyc + ΔN ₁ ). (steps 76 and 77).
This is because if the deceleration of the engine rotation, which will be described later, is extremely large, setting Nsyc+ _ΔN1 after calculating the deceleration may delay the start of the gear setting operation. Then, read the engine rotation speed NE ₁ at the time when the timer counts t ₁ seconds (for example, 48 msec) and the engine rotation speed NE ₀ at the time when t ₀ seconds (for example, 208 msec) is counted, and adjust the engine rotation based on these. Deceleration αE
Calculate = NE ₁ - NE ₀ /t ₀ - t ₁ (step 78~
82). Furthermore, this engine rotational deceleration αE is sequentially converted into reference decelerations a ₁ to a ₃ (for example, a ₁ = 700 rpm/sec,
a ₂ = 1100 rpm/sec, a ₃ = 1500 rpm/sec), when αE < a ₁ , the allowable value ΔN ₄ , when αE < a ₂ , the allowable value ΔN ₃ , and when αE < a 3, set the allowable value ΔN ₃ . is the allowable value ΔN ₂
and select each synchronizable area (Nsyc+ΔN ₄
~ΔN ₂ ) (steps 83 to 88). When the main gear rotation Ng enters the synchronizable range set in this way, it is determined that synchronization is possible, gear setting operation is started, and when synchronization is completed, the clutch 42 is fully connected and the fuel injection pump 41 is activated. The control lever is returned to its original position. Note that if the answer is NO in steps 71 to 75, the timer is reset in step 89.

In this way, the deceleration of the engine rotation during gear shifting operation is calculated, and based on this calculation result, the optimal synchronizable region corresponding to the deceleration is selected, and when the main gear rotation speed Ng enters this synchronizable region. Since it is determined that synchronization is possible and the gear set operation is started, when the deceleration of the engine rotation is large, the main gear is started from a high rotation range, and when the deceleration is relatively small, the shift set operation is started from a low rotation range. Therefore, the synchronized meshing of the main gear and the main shaft, that is, the start of the gear setting operation, is neither too late nor too early.
It is always executed in a timely manner and prevents shift errors from occurring.

(Effects of the invention) In summary, according to this invention, the driving range in which the transmission is to be shifted is determined based on the engine operating state and the vehicle speed, and the mechanical clutch is engaged and engaged to cause idle movement on the main shaft. In an automatic transmission device for a vehicle, comprising a speed change operation control means for synchronously connecting a rotating main gear and a main shaft,
A means for calculating the deceleration of engine rotation during a gear shift operation, and a plurality of tolerances of different sizes provided as relative rotational speed differences that allow the start of shift set operation of the main gear meshing with the main shaft rotational speed based on the calculation result. The optimum allowable value corresponding to the deceleration of the engine rotation at that time is selected from among the values to set the synchronizable range, and when the main gear rotation speed falls within this synchronizable range, it is determined that synchronization is possible. Since synchronization means is provided to instruct gear shifting operations, the synchronized meshing of the main gear and main shaft is always carried out in a well-timed manner without being too slow or too early, resulting in the effect of preventing shift errors from occurring. .

[Brief explanation of the drawing]

Figure 1 is an overall configuration diagram to clarify the configuration of this invention, Figure 2 is a schematic diagram explaining the mechanical configuration of an embodiment of this invention, Figure 3 is also a block diagram, and Figure 4 is a control diagram. FIG. 5 is a timing chart explaining the shift-up control, FIG. 6 and FIG. 7 are flowcharts explaining the operation of the earlier application, and FIG. 8 is a flowchart explaining the operation of the earlier application. FIG. 2 is a characteristic diagram illustrating the synchronization region of 41...Fuel injection pump, 42...Clutch,
43... Transmission, 49... Selector, 50... Accelerator opening sensor, 51... Selector position sensor, 53... Governor control device, 54
...Clutch stroke sensor, 55...Clutch actuator, 56...Main shaft rotation sensor, 57...Countershaft rotation sensor,
58...Shift position sensor, 59...Gear shift actuator, 60...Control unit, 61...Shift change control circuit, 62...
Synchro determination circuit, 63... Governor control circuit, 6
4... Transmission control circuit, 65... Clutch intermittent control circuit, 66... Engine rotation deceleration calculation circuit, 68... Engine rotation sensor.

Claims (1)

[Scope of Claim for Utility Model Registration] Synchronous connection of the main gear and the main shaft, which rotate freely on the main shaft by intermittent mechanical clutches in order to perform gear shifting operations of the transmission based on the operating state of the engine and the vehicle speed. In an automatic transmission system for a vehicle that includes a gear shift operation control means 61, a means 66 for calculating the deceleration of engine rotation during a gear shift operation, and a shift set operation of a main gear that meshes with the main shaft rotation speed based on the result of this calculation are possible. A synchronizable region is set by selecting a tolerance value that is larger as the calculated engine deceleration increases from among a plurality of tolerance values of different magnitudes set in advance as relative rotational speed differences. An automatic transmission device for a vehicle, comprising a synchronizing means 62 that determines that synchronization is possible when the synchronization is possible and instructs a shift operation when the synchronization is possible.