JPH0435560Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) This invention is an automatic transmission system for vehicles equipped with an exhaust brake,
In particular, the present invention relates to an automatic transmission system for an exhaust brake equipped vehicle equipped with an exhaust brake drive circuit.

(Prior Art) An automatic transmission device that automatically switches the transmission in the power transmission system of a vehicle to the optimum gear using a load signal based on accelerator operation and vehicle speed (for example, the specification of Japanese Patent Application No. 59-50747 filed by the present applicant) (disclosed in documents and drawings)
It has been known. The automatic shift control means of this automatic transmission device stores the gear stages according to the vehicle speed in advance as a data table, and when the gear stage suitable for the vehicle speed is automatically selected, it outputs an activation signal to the gear shift unit based on this. The gear train of the transmission can be automatically switched to the target gear position.
For example, as shown in FIG. 2, when the vehicle is running in 5th gear and shifts down to 4th gear due to a change in road resistance, the automatic transmission device performs automatic shift control as shown in FIG. 3. That is, the clutch is disengaged at time a based on the shift command, and then the gear train of the transmission connected to the clutch output shaft is changed from 5th gear to 4th gear.
As a result, the rotation speed NCL on the clutch output shaft side increases. Meanwhile, the engine speed NE is held, and reaches the clutch engagement start time c after passing the shift completion time b. Thereafter, the engine rotational speed NE is raised by the rotational force from the clutch output shaft side, and the rotational speeds of the engine and the clutch match to reach the clutch contact time d, and the gear shift is completed.

By the way, the higher the exhaust pressure of an internal combustion engine, the more
In response to the increased pump loss, an exhaust brake device is known that provides braking force to the vehicle by closing the exhaust passage in a timely manner using an exhaust brake valve.

(Problem to be solved by the invention) When a vehicle equipped with such an exhaust brake device and an automatic transmission device is running, if an automatic gear shift is performed while the exhaust brake is operating, the engine rotation will depend on the rotation caused by the exhaust brake. Since the decreasing tendency is significant, if the engine rotational speed hold processing is not performed sufficiently, the engine rotational speed will drop rapidly as shown by the two-dot chain line in FIG. For this reason, even if the engine speed is held, the engine speed increase process will be delayed until time e during the subsequent clutch engagement process, and the normal shift process time will be delayed.
It requires a longer shift processing time T2 than T1.
Such an increase in the shift processing time during exhaust braking tends to cause problems in terms of clutch durability or exhaust brake characteristics. An object of the present invention is to provide an automatic transmission device for a vehicle equipped with an exhaust brake that can eliminate problems associated with exhaust brake operation.

(Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention provides an exhaust brake device that obtains braking force by opening and closing an exhaust brake valve disposed in an exhaust path of an engine;
An automatic transmission to which the driving force of the engine is transmitted via a clutch, comprising an exhaust brake control means for controlling the operation of the exhaust brake device, and a clutch control means for automatically connecting and connecting the clutch. , outputs a clutch disengagement signal to the clutch control means at the start of a gear change of the automatic transmission, outputs an exhaust brake valve release signal to the exhaust brake control means, and after the gear change starts, outputs a clutch disengagement signal to the clutch control means, and after the gear change starts, outputs a clutch disengagement signal to the clutch control means; The present invention is characterized in that it includes a speed change control means that outputs a clutch connection signal so that the rotation of the clutch coincides with that of the clutch.

(Function) Since the gear change control means disengages the clutch by means of the clutch control means when the gear change starts, and releases the exhaust brake valve by the exhaust brake control means, the clutch control means disengages the clutch after changing the gear. Therefore, when a clutch connection signal is output so that the rotations of the engine and the clutch match, synchronization of both rotations can be performed without prolonging.

(Embodiment) FIG. 1 shows an automatic transmission system for a vehicle equipped with an exhaust brake (hereinafter simply referred to as an automatic transmission system) as an embodiment of the present invention. This automatic transmission device includes an automatic transmission controller 1 that functions as a clutch control means and a transmission control means for controlling a clutch and a transmission in a power transmission system mounted on a vehicle (not shown). Furthermore, this automatic shift controller 1 is connected to an exhaust brake drive circuit 2 as exhaust brake control means for controlling the operation of the exhaust brake device. The exhaust brake drive circuit 2 operates an exhaust valve 3, which is a butterfly valve that opens and closes an exhaust passage (not shown), and includes an exhaust brake switch 4, an exhaust brake cut relay 5 as a switching means, and an accelerator switch 6 connected in series. When all these switches are on, excitation current can be supplied to the electromagnetic valve 7. Here, the exhaust brake switch 4 is a normally open switch and serves as the main switch for operating the exhaust brake. The accelerator switch is a switch that is turned on only when the amount of depression of the accelerator pedal (not shown) is zero, and the electric breech cut relay 5 cuts off the normally closed contact based on an excitation current, which will be described later.

The electromagnetic valve 7 is an electromagnetic three-way valve with an opening for opening to the atmosphere, and connects the air tank 8 and an air cylinder 9 as an exhaust valve actuator when on, and opens the air cylinder 9 to the atmosphere when off. The air cylinder 9 opens and closes the exhaust valve 3 via a link (not shown), and closes when a clutch disengagement signal, which will be described later, is turned on.

The automatic speed change controller 1 consists of a microcomputer, and is connected to a power source 10 together with an exhaust brake drive circuit 2. This controller 1 includes an engine rotation sensor 11 (not shown) that generates an engine rotation speed signal, a load sensor 12 that generates an accelerator opening signal, a clutch rotation sensor 13 that generates a clutch output shaft rotation speed signal, a vehicle speed sensor 14, and a vehicle speed sensor 14 that disconnects the clutch. A clutch disengagement sensor 15 is connected to each of the clutches, which outputs a clutch disengagement signal when the adjacent clutch actuator is disengaged. In addition, the automatic transmission controller 1 controls a transmission electromagnetic switching valve 16 of a gear shift unit (not shown) that switches the gear train of the transmission by receiving a transmission signal from a transmission changeover switch (not shown) during transmission control, and Output signals are respectively sent to clutch electromagnetic switching valves 17 used when switching the clutch actuator. Furthermore, when the clutch disconnection signal is turned on, the terminal 18 is grounded to connect the electric breaker relay 5.
It operates so that an excitation current I flows through it. That is, the automatic transmission controller 1 as a transmission control means outputs a clutch disengagement signal to the clutch electromagnetic valve 17 as a clutch control means at the start of a gear change of the automatic transmission, and also outputs a clutch disengagement signal to the electric brake cut relay 5 on the exhaust brake control means side. An exhaust brake valve release signal (exciting current I) is output to the clutch, and after the gear change, a clutch connection signal is output to the clutch electromagnetic valve 17 so that the rotations of the engine and the clutch match.

Among the speed change controls performed by the automatic speed change controller 1, the automatic selection speed change control will now be described with reference to the flowchart shown in FIG. Note that the symbol C in FIG. 4 indicates a control step. First, since a shift changeover switch (not shown) is included in the automatic selection shift, so-called drive range, the optimum gear is selected based on the shift map based on the accelerator opening degree and vehicle speed, and the process proceeds from step 1 to step 2. . Then, it is determined whether or not the current gear is the same as the optimum gear. If the gear is the same, the process returns; if NO, the process proceeds to step 3, where a clutch disengagement signal is output to the clutch electromagnetic valve 17. Subsequently, in step 4, the terminal 18 is grounded and the excitation current I is caused to flow in order to disconnect the exhaust brake drive circuit 2 when the clutch disconnection signal is turned on, thereby stopping the exhaust brake even if it is in operation. Next, it is determined whether or not the optimum gear to be shifted from the current gear corresponds to downshifting. If so, in step 7 the engine rotation is maintained at idling rotation. After this, both proceed to step 8, adjust the gear position of the transmission to the optimum gear position, and reach time b (see Figure 3), and in step 9, from time c to time d.
During this time, match the rotation of the engine and clutch output shaft. At this point d, the clutch is fully engaged (step 10), and the process proceeds to step 11, where the excitation of the exhaust brake cut relay 5 on the exhaust brake drive circuit 2 is stopped, and the exhaust brake is constantly activated so that the exhaust brake can be returned to operation. Close the closing contact and return.

In the above, the exhaust brake drive circuit 2 is always disconnected every time the clutch disconnection signal is output, but instead of this, the exhaust brake drive circuit 2 is disconnected only when the exhaust brake switch 4 is turned on in addition to the output of the clutch disconnection signal. The exhaust brake drive circuit may be disconnected.

(Effects of the invention) As described above, since the automatic transmission according to the invention releases the exhaust valve during gear shift control, it is possible to prevent the engine speed from decreasing due to the exhaust brake during gear shifting, and reduce clutch rotation after changing gears. It is possible to prevent the synchronization process between the engine speed and the engine speed from taking a long time, prevent shift shock, and improve the durability of the clutch.

[Brief explanation of drawings]

Fig. 1 is a schematic configuration diagram of an automatic transmission as an embodiment of the present invention, Fig. 2 is a characteristic diagram of engine speed vs. vehicle speed, and Fig. 3 is a diagram showing the characteristics of the engine and clutch associated with automatic transmission control. The rotational speed diagram and FIG. 4 each show a flowchart of automatic selection speed change control performed by the automatic transmission system. DESCRIPTION OF SYMBOLS 1... Automatic gear shift controller, 2... Exhaust brake drive circuit, 3... Exhaust valve, 5... Electric brake cut relay, 9... Air cylinder, 16... Solenoid valve for gear change, 17... Clutch solenoid valve.

Claims (1)

[Scope of utility model registration request] An exhaust brake device that obtains braking force by opening and closing an exhaust brake valve disposed in an exhaust path of the engine, and an automatic transmission to which the driving force of the engine is transmitted via a clutch. exhaust brake control means for controlling the operation of the brake device; clutch control means for automatically engaging and disengaging the clutch; It is characterized by comprising a shift control means for outputting an exhaust brake valve release signal to the brake control means, and outputting a clutch connection signal to the clutch control means after changing the gear so that the rotations of the engine and the clutch match. automatic transmission system for vehicles equipped with exhaust brakes.