JPH0810663Y2 - Warming device for internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a warm-up device for an internal combustion engine, and more specifically, it has an idle-up function and an exhaust throttle function for promoting warm-up, The present invention relates to a warm-up device for an internal combustion engine which performs idle-up and exhaust throttling during idling.

[Prior Art] Conventionally, at the start of warm-up, first, an idle-up mechanism (for example, a fuel injection pump) is operated to increase the amount of supplied fuel, and then an exhaust throttle valve mechanism (for example, an exhaust retarder) is operated. A warm-up device has been proposed in which exhaust warming is performed by performing exhaust throttling (Japanese Utility Model Publication No. 59-190951). This is a device that prevents the driver from being shocked when the warm-up device operates while the vehicle is running, because the exhaust throttle is performed before the fuel increase and the engine speed drops sharply. is there.

On the other hand, contrary to the above, when releasing the warm-up, that is, when releasing the idle-up and exhaust throttle, special release conditions (for example, as shown in Japanese Utility Model Publication No. 55-165834), the engine is returned to the normal idling state. Instead of letting
Except when the engine speed is increased relative to the operation amount of the accelerator pedal to immediately start the vehicle), for example, the release timing of the warm-up is set at predetermined vehicle speed and cooling water temperature. The engine is returned to the normal idling state by the release timing, and at the same time the exhaust retarder is opened to reduce the exhaust pressure.

[Problems to be Solved by the Invention] However, in the conventional warm-up device described above, in the exhaust throttle valve mechanism, there is an operation delay in releasing the exhaust throttle due to, for example, the tolerance or deterioration of the exhaust retarder that constitutes the mechanism. The problem is that it occurs.

For this reason, when the warm-up is released, the release operation of the exhaust throttle is delayed, so that the idle-up is released before the release of the exhaust throttle, that is, the exhaust retarder is not yet released. Even if the engine is closed, the idle-up is canceled, the fuel supply to the engine is reduced, and if the engine speed is drastically reduced to the normal idling state, the engine may stall due to exhaust load. was there. Particularly, in the one disclosed in Japanese Utility Model Laid-Open No. 59-190951, this problem is remarkable because the opening and closing of the exhaust throttle valve becomes slow.

The present invention has been made in view of the above-mentioned circumstances, and an object thereof is to cancel the exhaust throttle even if the exhaust throttle valve mechanism such as the exhaust retarder has a delay in operation due to tolerance or deterioration at the time of releasing the warm-up. An object of the present invention is to provide a warm-up device for an internal combustion engine that can reliably prevent an engine stall or the like from occurring when idle-up is canceled before canceling.

[Means for Solving the Problems] In order to achieve the above object, the present invention, as shown in FIG. 1, has an exhaust throttle valve mechanism M3 provided in an exhaust pipe M2 of an internal combustion engine M1 and an internal combustion engine. The idle up mechanism M4, which increases the amount of fuel supplied to M1 to idle up, and the exhaust throttle valve mechanism M3 are deactivated, and the idle up mechanism is also released.
A warm-up device for the internal combustion engine M1 that includes an operation releasing means M5 for releasing the operation of M4, and that activates the exhaust throttle valve mechanism M3 and warms up the idle-up mechanism M4 during warm-up of the internal combustion engine M1. In order to release the warm-up of the internal combustion engine M1 and return to normal idling, the deactivating means M5
When the engine is driven, a detection means M6 is provided for detecting completion of deactivation of the exhaust throttle valve mechanism M3 and starting deactivation of the idle up mechanism M4 based on the detection.

[Operation] Therefore, as shown in FIG. 1, the internal combustion engine warm-up device according to the present invention uses the exhaust throttle valve M5 to cancel the warm-up of the internal combustion engine M1 to return to normal idling. The release operation of the mechanism M3 is immediately performed. Then, the detection means M6 detects the completion of the deactivation of the exhaust throttle valve mechanism M3, and starts the deactivation of the idle-up mechanism M4 based on the detection.

That is, by releasing the operation of the exhaust throttle valve mechanism M3,
The idle-up is maintained until the exhaust flow of M2 is allowed and the exhaust load of the internal combustion engine M1 is surely reduced.

[Embodiment] An embodiment in which the present invention is embodied in a diesel engine vehicle equipped with an exhaust brake (exhaust retarder) will be described in detail with reference to the drawings.

FIG. 2 is a block diagram showing the electrical construction of the warm-up device in this embodiment. This warm-up device is roughly composed of a retarder solenoid 1 which constitutes an exhaust throttle valve mechanism provided in the exhaust pipe of an engine (not shown), and an idle-up mechanism for increasing the fuel supplied to the engine for idle-up. A vacuum switching valve solenoid for idle-up (hereinafter simply referred to as "VSV solenoid") 2 and a release means for operating the solenoids 1 and 2 based on signals from various switches and sensors and releasing the operation. The drive circuit 3 which comprises it is provided.

Here, the retarder solenoid 1 is a VSV (not shown) for opening and closing the exhaust throttle valve 42 provided in the middle of the exhaust pipe 41.
It is built in. And the exhaust throttle valve 42,
Exhaust throttle valve with a VSV including the retarder solenoid 1, a diaphragm actuator 44 equipped with a rod 43 that expands and contracts based on the operation of the VSV, a link 45 that closes and opens the exhaust throttle valve 42 in conjunction with the expansion and contraction of the rod 43. A known exhaust retarder as a mechanism is configured.

Therefore, when the retarder solenoid 1 is energized, the VSV operates and negative pressure is supplied to the diaphragm actuator 44, and the rod 43 contracts. As a result, the exhaust throttle valve 42 is closed via the link 45, the flow of the exhaust gas in the exhaust pipe line 41 is restricted, the exhaust load of the engine is increased, the warm-up of the engine is promoted, and the engine brake is applied. Can be hung. On the other hand, when the retarder solenoid 1 is turned off, the VSV operates and the atmospheric pressure is changed to the diaphragm actuator 4
4, the rod 43 is extended. As a result, the exhaust throttle valve 42 is opened via the link 45, and the exhaust pipe line is opened.
The flow of exhaust gas at 41 is allowed to reduce the exhaust load of the engine.

Further, the VSV solenoid 2 is incorporated in the VSV 5 which is operated to adjust the injection amount from the fuel injection pump 4 in order to increase the fuel supplied to the engine, as shown in FIG. And VSV including the VSV solenoid 2
5, a diaphragm actuator 7 equipped with a rod 6 that expands and contracts based on the operation of the VSV 5, a throttle (interlocked with an accelerator pedal (not shown)) 8 provided in the fuel injection pump 4, and the throttle 8 with the rod 6 The idle-up mechanism is constituted by the operation plate 9 and the like which are rotated by the expansion and contraction of.

Therefore, when the VSV solenoid 2 built in the VSV 5 is energized, the VSV 5 operates and a negative pressure from a vacuum pump (not shown) is supplied to the diaphragm actuator 7, and the rod 6 thereof is contracted. As a result, the tip of the rod 6 engages with the operating plate 9 and the plate 9
Is rotated. When the operation plate 9 is rotated, the bolt 10 attached to the tip of the operation plate 9 rotates the throttle 8 and the injection amount from the fuel injection pump 4 is increased. That is, when the engine idle-up is started, the negative pressure from the vacuum pump is applied to the diaphragm actuator 7.
Immediately introduced into the engine, the injection quantity is rapidly increased. On the other hand, by turning off the VSV solenoid 2
The SV5 operates and atmospheric pressure is supplied to the diaphragm actuator 7 from the atmosphere open side, and the rod 6 thereof is extended. As a result, the rod 6 is separated from the operating plate 9 and the throttle 8 is pivotally returned via the bolt 10.
The injection amount from the fuel injection pump 4 is reduced and the idle-up is canceled. That is, the normal idling state is restored.

Next, the various switches and sensors will be described. As shown in FIG. 2, the key switch 12 is connected to the plus terminal side of the in-vehicle battery 11 via the fuse 13. The key switch 12 can be switched to three positions of a start position terminal 12a, an operation position terminal 12b and an off position terminal 12c. The start position terminal 12a of the key switch 12 is connected to the input terminal 14A of the drive circuit 3.

The starter relay 15 is a relay for operating an engine starter (not shown), and has one end connected to the start position terminal 12a of the key switch 12 and the other end connected to the minus terminal side of the vehicle battery 11.

The accelerator switch 16 is a switch that is turned off when an accelerator pedal (not shown) is depressed and is turned on when the accelerator pedal is not depressed. Neutral switch
A switch 17 is turned on when the transmission (not shown) is in the neutral state and is turned off when the transmission is not in the neutral state. The retarder main switch 18 is a switch that is turned on when exhaust throttling is performed and turned off when exhaust throttling is not performed.

Then, one end of each of these switches 16 to 18 has a fuse 19
Are connected to the operation position terminal 12b and the start position terminal 12a of the key switch 12, respectively. The other ends of the accelerator switch 16 and the neutral switch 17 are connected to the input terminals 14B and 14C of the drive circuit 3, respectively, and the other end of the retarder main switch 18 is connected via a main indicator 20 for displaying the ON operation. It is connected to the minus terminal side of the vehicle-mounted battery 11.

The MAX worm switch 21 is a switch that interlocks with a temperature setting switch of a heater for vehicle interior heating (not shown) that uses engine heat. The MAX worm switch 21 is turned on when the set temperature by the set temperature switch is MAX warm, and is set to a value other than MAX warm. It is supposed to turn off. One end of the MAX worm switch 21 is connected to the operating position terminal 12b of the key switch 12 via the fuse 22, and the other end is connected to the input terminal 14D of the drive circuit 3.

The heater switch 23 is also a switch for turning on / off a heater for heating the interior of the vehicle, and one end thereof is connected to the fuse 22 via the heater relay 24. The other end of the heater switch 23 is connected to the minus terminal side of the vehicle-mounted battery 11. Furthermore, the input terminal 14 of the drive circuit 3 is between the heater switch 23 and the heater relay 24.
Connected to E.

The clutch switch 25 is a switch that turns off when the clutch pedal (not shown) is stepped on, and turns on when the clutch pedal is not stepped on.One end of the clutch switch 25 is connected between the retarder main switch 18 and the main indicator 20. , The other end is connected to the input terminal 14F of the drive circuit 3. Further, the vehicle speed sensor 26 is composed of a reed switch arranged in the vicinity of a magnet rotated by a speedometer cable (not shown), and is a signal which is turned on / off each time the vehicle travels a predetermined distance, that is, a cycle proportional to the vehicle speed. on·
Output an off signal. One end of the vehicle speed sensor 26 is connected to the minus terminal side of the vehicle-mounted battery 11, and the other end is connected to the input terminal 14G of the drive circuit 3.

Further, the limit switch 38 as a detecting means is provided detachably on a link 45 that is rotated in conjunction with opening and closing of the exhaust throttle valve 42, and the exhaust throttle valve 42 is in an open state, that is, the exhaust throttle is released. It turns on in the open state, and turns off in other states. This limit switch 38 is connected to the input terminal 14 of the drive circuit 3.
Connected to H.

Next, the configuration of the drive circuit 3 will be described. The vehicle speed detection circuit 27 is a circuit for inputting a signal from the vehicle speed sensor 26, and one end of its power supply terminal has a power supply terminal 28A, a fuse 19,
In-vehicle battery 11 via key switch 12 and fuse 13
Is connected to the plus terminal side and the other end is connected to the minus terminal side of the vehicle battery 11 via the power supply terminal 28B.
The vehicle speed detection circuit 27 is a circuit having a predetermined hysteresis, and when the vehicle speed increases based on the signal from the vehicle speed sensor 26, for example, the logical value "0 (low)" is a logical value at a speed of 15 km per hour. When a signal that becomes "1 (high)" is output and the vehicle speed decreases, for example, a signal that the logical value "1" becomes the logical value "0" is output at a boundary of 10 km / h.

The first AND circuit 29 outputs the output signal from the vehicle speed detection circuit 27, the ON / OFF signal of the clutch switch 25, the ON / OFF signal of the neutral switch 17 input via the knot circuit 30, and the accelerator switch 16. Input an on / off signal.

Further, the second AND circuit 31 is an ON / OFF signal of the heater switch 23 inputted via the knot circuit 32, an ON / OFF signal of the MAX warm switch 21 and a neutral switch inputted via the delay circuit 33. The ON / OFF signal of 17 and the ON / OFF signal of the start position terminal 12a of the key switch 12 inputted via the knot circuit 34 are inputted respectively.

The third AND circuit 35 inputs the output signal of the second AND circuit 31 and the signal from the accelerator switch 16, and outputs the output signal to the first OR circuit 36.

The first OR circuit 36 inputs the output signals of the third AND circuit 35 and the first AND circuit 29, and outputs the output signals to the retarder solenoid 1 via the output terminal 37A.

Further, the second OR circuit 39 inputs the output signal of the second AND circuit 31 and the output signal from the limit switch 38 input via the knot circuit 40, respectively, and outputs the output signal via the output terminal 37B. Output to VSV solenoid 2.

Next, the operation of the warm-up device for the internal combustion engine configured as described above will be described.

In a currently stopped vehicle, the exhaust retarder is actuated to accelerate warm-up, the exhaust throttle valve 42 is closed, and the heater for in-vehicle heating is operated while performing exhaust throttling. The key switch 12 is in the operating position terminal 12b
, Accelerator switch 16, MAX warm switch 21, neutral switch 17, retarder main switch 18, clutch switch 25, and heater switch.
23 are in the ON state, and the limit switches
38 is in the off state, the vehicle speed sensor 26 is not turned on / off, and a signal proportional to the vehicle speed is not output.

Therefore, in this state, the signal from the vehicle speed detection circuit 27,
Similarly, the signal from the clutch switch 25 and the signal input from the neutral switch 17 via the knot circuit 30 each have a logical value of "0", and the signal from the accelerator switch 16 has a logical value of "1". The output of the circuit 29 has a logical value "0".

Also, a heater switch input via the knot circuit 32.
The signal from the signal 23, the signal from the MAX warm switch 21, the signal from the neutral switch 17 input via the delay circuit 33, and the signal from the key switch 12 input via the knot circuit 34 are logical values "1", respectively. , And the output of the second AND circuit 31 has the logical value “1”.

Therefore, the output of the second OR circuit 39 becomes the theoretical value "1", and the VSV solenoid 2 is energized via the output terminal 37B. At this time, as shown by the solid line in FIG. 2, since the exhaust throttle valve 42 is closed and the exhaust throttle is performed, it is input to the second OR circuit 39 via the knot circuit 40. The signal from the limit switch 38 is the theoretical value "1"
Has become.

On the other hand, the third AND circuit 35 outputs a logical value to the OR circuit 36 of the next stage based on the output signal of the logical value "1" of the second AND circuit 31 and the signal of the logical value "1" of the accelerator switch 16. The output signal of "1" is output. As a result, the OR circuit
Even if the output logical value of the first AND circuit 29 is "0", the circuit 36 energizes the retarder solenoid 1 based on the output of the logical value "1" of the third AND circuit 35. That is,
The amount of injection from the fuel injection pump 4 is increased via the VSV 5 and the diaphragm actuator 7 shown in FIG. 3, and the idle-up is performed.

Then, in this state, if one of the warm-up operation conditions is released, that is, assuming that the vehicle interior is sufficiently heated, the driver turns off the heater switch 23 to stop the heating, the knot circuit 32 The logical value of the signal input to the second AND circuit 31 via "1" changes from "1" to "0", and the output logical value of the second AND circuit 31 changes from "1" to "0". Therefore, the output logical value to the second OR circuit 39 is "0".
At the same time, the output logical value to the third AND circuit 35 becomes "0".

As a result, the output logical value of the first OR circuit 36 immediately becomes "0", and the retarder solenoid 1 immediately becomes non-energized as shown at time t1 in FIG.

On the other hand, in the second OR circuit 39, the logical value of the signal from the limit switch 38 input via the knot circuit 40 remains "1", so at this point (time t1), VSV
The solenoid 2 holds the energized state.

When the retarder solenoid 1 is de-energized and the rod 43 of the diaphragm actuator 44 extends through the VSV to open the exhaust throttle valve 42, the link 45 linked to the rod 43 becomes the limit switch 38. When engaged, the switch 38 is turned on. Because of this, the knot circuit
The logical value of the signal input to the second OR circuit 39 via 40 becomes "0", and the output logical value of the circuit 39 becomes "0".
VSV solenoid 2 is de-energized. That is, as shown in FIG. 4, after a time t1 when the retarder solenoid 1 is in the non-energized state, a time t2 when a predetermined time T from the closed state to the opened state of the exhaust throttle valve 42 elapses. At, VSV solenoid 2 is de-energized. As a result, V
The injection amount from the fuel injection pump 4 is reduced via the SV5, the diaphragm actuator 7, etc., and the idle-up is canceled.

That is, the operation of the exhaust retarder is released and the exhaust throttle valve
Until the valve 42 is opened, the idle-up state is maintained, the exhaust throttle valve 42 is reliably opened, and the exhaust throttle is reliably released, and then the idle-up is immediately released.

Therefore, for example, even when there is a slight delay in the opening / closing operation of the exhaust throttle valve 42 due to tolerance or deterioration of the diaphragm actuator 44 or the like that constitutes the exhaust retarder, after the exhaust retarder is deactivated, that is, the exhaust throttle valve 42. After it has been securely opened, the idle-up is released, the normal idling state is restored, and the engine warm-up is released. That is, after the exhaust gas flow in the exhaust pipe line 41 is allowed and the exhaust load of the engine is reduced, the idle-up is released. Therefore, it is possible to prevent the exhaust load applied to the engine from being increased by releasing the idle-up state while the exhaust throttle valve 42 of the exhaust retarder is closed, and the engine can be smoothly operated in the normal idling state without causing engine stall. Can be returned to.

Also, in the above case, it was explained that the warm-up is released when the driver turns off the heater switch 23. However, even when the MAX warm switch 21 is turned off, the warm-up is released. Can be done similarly.

The present invention is not limited to the above-described embodiment, and a part of the configuration can be appropriately modified without departing from the spirit of the invention and can be carried out as follows.

(1) In the above embodiment, the limit switch 38 that is turned on / off in conjunction with the opening / closing of the exhaust throttle valve 42 is used as the detection means, but the invention is not limited to this, and the opening / closing amount of the exhaust throttle valve 42 is detected. A sensor that detects the pressure in the exhaust pipe 41 or the like may be used as the detection unit.

(2) In the above-described embodiment, the engine warm-up is released when the heater switch 23 is turned off or when the MAX warm switch 21 is turned off. It is set at the time when the water temperature etc. reaches a predetermined value, and when the timing for releasing the warm-up comes, the exhaust throttle is released to reduce the exhaust load, and the idle up state is delayed after that. May be configured to return to a normal idling state.

(3) In the above-described embodiment, in the diesel engine vehicle equipped with the exhaust retarder as the exhaust brake used while traveling, the exhaust retarder is also used to promote warm-up, but separately from the exhaust brake. It may be embodied in a diesel engine provided with a dedicated exhaust throttle valve mechanism used only during warm-up.

(4) In the above embodiment, the warm-up device is embodied as a diesel engine vehicle, but it may be embodied as a vehicle equipped with an internal combustion engine other than a diesel engine.

[Effects of the Invention] As described in detail above, according to the warm-up device for an internal combustion engine of the present invention, the completion of the operation release of the exhaust throttle valve mechanism such as the exhaust retarder is detected, and the idle up mechanism of the idle up mechanism is detected based on the detection. Since the detection means for starting the operation release is provided, even if there is a delay in operation due to tolerance or deterioration of the exhaust throttle valve mechanism when releasing warm-up, idle-up is released before the exhaust throttle is released and engine stall etc. occurs. It has an excellent effect that it can surely be prevented from happening.

[Brief description of drawings]

FIG. 1 is a basic configuration diagram showing a basic configuration of a warm-up device for an internal combustion engine according to the present invention, and FIG. 2 is a block diagram showing an electrical configuration of the warm-up device according to an embodiment of the present invention. FIG. 3 is a diagram showing the structure of the idle-up mechanism, and FIG. 4 is a time chart for explaining the timing gap between the deenergization of the retarder solenoid and the de-energization of the VSV solenoid. In the figure, M1 is an internal combustion engine, M2 is an exhaust pipe line, M3 is an exhaust throttle valve mechanism, M4 is an idle up mechanism, M5 is a deactivating means, M6 is a detecting means, 1 is a retarder solenoid, 42 is an exhaust throttle valve,
44 is a diaphragm actuator, 45 is a link (1,42,4
4,45 and the like constitute an exhaust throttle valve mechanism), 41 is an exhaust pipe line, 3 is a drive circuit as an operation releasing means, 2 is a VSV solenoid, 4 is a fuel injection pump, 5 is VSV, and 6 is a rod. ,
7 is a diaphragm actuator, 8 is a throttle, 9
Is an operating plate, 10 is a bolt (2, 4 to 10 constitute an idle-up mechanism), and 38 is a limit switch as a detecting means.

Claims (1)

[Scope of utility model registration request] 1. An exhaust throttle valve mechanism provided midway in an exhaust pipe of an internal combustion engine, an idle up mechanism for increasing fuel supplied to the internal combustion engine to idle up, and an operation of the exhaust throttle valve mechanism being released. And an operation releasing means for releasing the operation of the idle-up mechanism, the internal combustion engine performing idle-up by operating the exhaust throttle valve mechanism and operating the idle-up mechanism while the internal combustion engine is warming up. In the warm-up device of, when the operation releasing means is driven to release the warm-up of the internal combustion engine and return to normal idling, the completion of the operation release of the exhaust throttle valve mechanism is detected, and the detection is performed. A warm-up device for an internal combustion engine, comprising: a detection means for starting operation release of the idle-up mechanism based on the detection means.