JPH0341067Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to an improvement in an automatic transmission for a vehicle that interlocks an exhaust brake at the time of upshifting.

[Prior Art] Recently, many vehicles are equipped with automatic transmissions that automatically change gears for easy driving, and in order to save fuel, automatic transmissions using mechanical clutches have been proposed. (For example, Utility Application No. 57-163228 filed by the present applicant). Furthermore, in order to reduce costs and facilitate gear setting, it has been proposed to use a non-synchronized transmission in the above-mentioned automatic transmission (for example,
59-20536 etc.).

By the way, in this non-synchronized transmission,
There is an automatic system that electronically detects that the relative speed difference between two gears to be engaged has become less than a specified value, that is, that they have synchronized, and starts gear setting. Here, in order to shorten the synchronization time, immediately after setting the transmission to neutral when shifting up, re-engage the clutch.
A method has been proposed in which the clutch is turned ON and the rotation speed of the countershaft, that is, the rotation speed of the main gear, is quickly reduced to the synchro speed using the drop in engine and rotation speed, and the shift set is performed with the clutch ON. (Gan Sho 59-70610). Furthermore, in order to speed up the fall of the engine rotation, a system has been proposed in which an exhaust brake is linked (Utility Application No. 160532/1989 filed by the present applicant). However, interlocking the exhaust brake is undesirable as it increases engine noise and air consumption, and it is also not desirable to use the exhaust brake when driving on flat roads, especially when there is little desire to shorten shift change time. It is not recommended to use it.

[Purpose of the invention] This invention was made in view of the above circumstances.
The purpose is to provide an automatic transmission for a vehicle that reduces engine noise and air consumption by disengaging the exhaust brake when driving on a flat road.

[Structure of the invention] According to the invention, the shift position detection means, the clutch position detection means, the main gear rotational speed detection means, the main shaft rotational speed detection means, and whether or not the two rotational speeds are synchronized at the time of shift up. a synchronization determination means for determining the synchronization determination means; and a clutch discontinuation means operated by the output from the synchronization determination means;
The automatic transmission for a vehicle includes an exhaust brake operating means and a shift operation means and interlocks the exhaust brake when shifting up, and is provided with an exhaust brake interlock release means for allowing a driver to selectively release the interlock of the exhaust brake.

[Operations and Effects of the Invention] Therefore, when driving on flat land, the driver can release the exhaust brake interlock using the exhaust brake interlock release means, and as a result, engine noise and air consumption can be reduced.

[Preferred Embodiment] When implementing the present invention, it is preferable that the exhaust brake interlock release means be configured as a push button type exhaust brake interlock switch that interlocks the exhaust brake when ON and releases the interlock of the exhaust brake when OFF.

[Examples] Examples of the present invention will be described below with reference to the drawings.

FIG. 1 shows a hardware configuration diagram of an embodiment of the present invention, and FIG. 2 shows a control block diagram. In the figure, a non-synchronized transmission 30 is attached to an engine 10 via a mechanical clutch 20, and its output shaft is connected to a rear axle (not shown) via a propeller shaft 31. The engine 10 is provided with an exhaust brake actuator 11, which is an exhaust brake operating means for operating an exhaust brake.

The clutch 20 is provided with a clutch position sensor 21 which is a clutch position detecting means for detecting the engagement/disengagement state of the clutch from the stroke amount of the clutch, and a clutch actuator 22 which is a clutch engagement/disconnection means for connecting/disconnecting the clutch. There is.

The transmission 30 includes a countershaft rotation sensor 32 which is a main gear rotation speed detection means;
A vehicle speed sensor 33 serving as a main shaft rotational speed detection unit, a shift position sensor 34 serving as a transmission shift position detection unit, and a shift change actuator 35 serving as a shift operation unit for the transmission 30 are provided.

On the other hand, in the operator's cab (not shown), there is provided a push-button type exhaust brake interlock switch 12, which is an exhaust brake interlock release means that interlocks the exhaust brake when turned on and releases the interlocking of the exhaust brake when turned off. Further, an accelerator pedal 14 provided in a driver's cab (not shown) is provided with a load sensor 13 that detects the engine load based on the pedal opening. And these sensors, equipment 11, 12,
21, 22, 32, 33, 34 and 35 are connected to a control unit 40.

The control unit 40 controls the shift position sensor 3 based on the detection signals from the vehicle speed sensor 33 and the load sensor 13.
A shift change determination circuit 41 that determines whether or not a shift change is to be performed based on the detection signal from 4.
A synchronization determination circuit 42 determines whether the rotational speeds of the main gear and the main shaft are synchronized based on the output of the shift change determination circuit 41 and the detection signals from the countershaft rotation sensor 32 and the vehicle speed sensor 33, and the clutch position. sensor 2
1, a transmission control circuit 44 that controls the shift change actuator 35 based on the detection signal of the shift position sensor 34, and an exhaust brake interlocking switch. 12
An exhaust brake control circuit 45 that controls the exhaust brake actuator 11 based on ON/OFF is provided, and signals from these circuits are inputted to each circuit as a control signal.

Next, the operation of the shift up timing chart shown in FIG. 3 will be mainly explained.

Now, while the exhaust brake interlocking switch 12 is turned ON and the exhaust brake interlocking switch 12 is turned on, the shift change determination circuit 41 shifts up from 4th gear to 5th gear based on detection signals from the load sensor 13, vehicle speed sensor 33, and shift position sensor 34. When determining what to do,
Clutch engagement control circuit 4 based on the judgment signal
Clutch actuator 22 by the output from 3.
operates to turn off the clutch 20 (state A),
The shift change actuator 35 is actuated by the output from the transmission control circuit 44 to bring the transmission 30 to the neutral position (state B). Next, when the shift position sensor 34 detects that it is in the neutral position, this detection signal is transmitted to the transmission control circuit 4.
4 to the synchro determination circuit 42, and the synchro determination circuit 42 determines that the main gear rotation speed Ng is the main shaft rotation speed based on the detection signals from the countershaft rotation sensor 32 and the vehicle speed sensor 33.
Determine whether it is greater than Ns. In the case of Ng>Ns (in the case of Fig. 3), the clutch discontinuation control circuit 43
The clutch actuator 22 is actuated to connect the clutch 20 via the exhaust brake control circuit 45 to connect the clutch 20 (state C), and the exhaust brake is actuated by the exhaust brake actuator 11 via the exhaust brake control circuit 45 (state D). This forcibly reduces the rotational speed Ng of the main gear, which is always in mesh with the counter gear. The synchro determination circuit 42 then
Ng = Ns + ΔN2 (ΔN2 is the speed difference ΔN1 that allows gear shifting even if the exhaust brake operation is stopped, i.e. the speed difference that is predicted to allow deceleration to the synchro speed within a short time) Exhaust brake control is performed at point F The operation of the exhaust brake is stopped by the exhaust brake actuator 11 via the circuit 45 (state G). Next, at time H when Ng=Ns+ΔN1, the synchro determination circuit 42 operates the shift change actuator 35 via the transmission control circuit 44 to perform a shift change to 5th gear (state I).

On the other hand, if the exhaust brake interlocking switch 12 is turned off while driving on a flat road, the exhaust brake will not be activated during the above-mentioned shift operation, and the time until the main gear rotation speed becomes equal to the main shaft rotation speed, i.e. For example, the synchronization time is the synchronization time when the exhaust brake is activated.
It is longer at 1.5 seconds compared to 1.0 seconds. However, on flat roads, even if it takes some time to shift, a smooth shift can be achieved, and the increase in engine noise and air consumption caused by exhaust braking can be reduced, resulting in a comfortable drive feeling. is obtained.

[Summary] As explained above, according to the present invention, an exhaust brake interlock release means for releasing the interlocking of the exhaust brake is provided in the automatic transmission that interlocks the exhaust brake when shifting up. The release means can release the interlocking of the exhaust brake, thereby reducing engine noise and air consumption caused by the exhaust brake.

[Brief explanation of drawings]

FIG. 1 is a hardware configuration diagram showing an embodiment of the present invention, FIG. 2 is a control block diagram of this embodiment,
FIG. 3 is a diagram of a shift up timing chart according to the present invention. 11...Exhaust brake key actuator, 12...
...Exhaust brake interlock switch, 21...Clutch position sensor, 22...Clutch actuator,
32... Counter shaft rotation sensor, 33...
Vehicle speed sensor, 34...Shift position sensor, 35...
...Shift change actuator, 42... Synchro judgment circuit.

Claims (1)

[Scope of utility model registration request] a shift position detection means, a clutch position detection means, a main gear rotational speed detection means, a main shaft rotational speed detection means, a synchronization determination means for determining whether or not the two rotational speeds are synchronized at the time of shift up, and the synchronization determination. An automatic transmission for a vehicle is provided with a clutch engagement means, an exhaust brake actuation means, and a shift operation means operated by an output from the means, and which interlocks the exhaust brake when shifting up, wherein the interlocking of the exhaust brake is selectively released by a driver. An automatic transmission for a vehicle, characterized in that an exhaust brake interlock release means is provided.