JPH03499Y2 - - Google Patents

Description

[Detailed explanation of the idea]

The present invention relates to an engine warm-up device. 2. Description of the Related Art Conventionally, an engine is known in which an exhaust brake valve is provided in an exhaust pipe line, which is capable of fully or almost completely closing the exhaust pipe and maintaining a brake operating position in which the exhaust brake is activated. On the other hand, it is also known that an engine warm-up effect can be obtained by increasing the flow resistance of the engine exhaust pipe. Therefore, for example, if the exhaust brake is operated even when the car is running, an effect of warming up the engine can be obtained, but on the other hand, the drivability of the engine is seriously impaired. Therefore, it is known that a valve dedicated to warming up the exhaust pipe is installed in the exhaust pipe line separately from the exhaust brake valve, but this valve is separate from the exhaust brake valve. Therefore, it has the disadvantage of being extremely disadvantageous in terms of weight, space, and cost. Furthermore, as shown in, for example, Japanese Unexamined Patent Publication No. 56-104127, a stopper capable of holding the above-mentioned exhaust brake valve at a warm-up position intermediate between the fully open position and the exhaust brake position is provided so as to be retractable. It has been proposed that the above-mentioned exhaust brake valve has the function of a warm-up valve. However, this conventional device requires a separate cable or fluid pressure actuator and piping for changing the circumference of the stopper, which not only increases the number of parts but also has disadvantages in terms of space. This invention was devised in view of the above, and includes an exhaust brake valve that can open and close the exhaust pipe of an engine,
one hydraulic actuator that is connected to the exhaust brake valve and has a movable wall biased by a spring, and opens and closes the exhaust brake valve by fluid pressure acting on the movable wall and biasing force of the spring; , a fluid pressure supply source that generates the fluid pressure, and adjusting the fluid pressure of the fluid pressure supply source and supplying it to the fluid actuator to fully close or nearly fully close the exhaust brake valve. a fluid pressure regulating device that maintains the exhaust brake valve at the second predetermined opening and a second predetermined opening that is greater than the first predetermined opening and smaller than the full open; This engine warm-up device is characterized by comprising an opening degree changing section that fully opens the exhaust brake valve when the engine speed is in a high-speed rotation range larger than a predetermined speed when the engine is running. Hereinafter, an embodiment in which the present invention is applied to an automobile engine will be described in detail with reference to the accompanying drawings. In the figure, reference numeral 2 denotes an exhaust pipe of the engine, 4 a casing installed in the exhaust pipe, 6 a slide-type exhaust valve that opens and closes the exhaust pipe 2 in the casing, and 8 fixed to the casing 4 to exhaust the exhaust pipe. This is an actuator that operates the valve 6. The actuator 8 has two chambers 10 and 12 separated by a movable wall 9 that is linked to an exhaust valve 9. The chamber 10 is connected to a vacuum source 16 via a passage 4, and the chamber 12 is It is open to the atmosphere. Further, the actuator 8 has a return spring 17 that urges the exhaust valve 6 in a direction to fully open it. 1
Reference numeral 8 denotes an on-off valve that is interposed in the passage 14 and closes the passage 14 only when the coil 20 is energized;
2 is interposed in the passage 14, and usually a vacuum source 16
It is a three-way valve that shuts off the chamber 10 of the actuator 8 and introduces the atmosphere into the chamber 10, and connects the chamber 10 and the vacuum source 16 when the coil 24 is energized. 26 is a regulator valve provided in parallel with the on-off valve 18 in the passage 14, and includes a chamber 30 separated from the atmosphere by a movable wall 28 and a return spring 32.
The movable wall 28 is configured to be closed when the biasing force of the movable wall 28 due to the negative pressure within the chamber 30 becomes greater than the biasing force of the spring 32. Note that this chamber 30 and the chamber 10 of the actuator 8 are always kept at the same pressure, and the regulator valve 2
6 is closed, the movable wall 9 is held at the position shown by the solid line in the figure, and the exhaust valve 6 completely closes or almost completely closes the exhaust pipe 2. The exhaust brake operating position is slightly open from the first predetermined opening degree. Second warm-up device with higher temperature
The biasing force of the return spring 17 is set so that the opening is maintained at a predetermined degree. 34 is an orifice provided in series with the regulator valve 26. The on-off valve 18, the three-way valve 22, and the regulator valve 26 constitute a fluid pressure regulating device that regulates the fluid pressure acting on the actuator 8. 36 is a power source, 38 is a fuse, and 40 is a cold start switch interposed between the fuse and the coil 24 of the three-way valve 22. 42, 44, and 46 are an exhaust brake switch, an accelerator microswitch, and a clutch microswitch, which are connected in series, respectively; the accelerator microswitch 44 is closed only when the accelerator pedal (not shown) is not depressed; is closed only when a clutch pedal (not shown) is not depressed. 48 is a double warm-up switch, 50 is a water temperature switch that closes only when the temperature of the engine cooling water is below an arbitrary set value, and 52 is a low speed switch when the engine speed is below an arbitrary set value. The rotary switch 52, which is a rotary switch that closes only when the rotary switch is rotated, functions as an opening degree changing section within the scope of the utility model registration claims. Further, 54 is a relay switch for giving priority to the exhaust brake, which closes only when the coil 56 is energized. The warm-up switch 48 has one end connected in series with the water temperature switch 50 and the rotation speed switch 52 between the fuse 38 and the relay switch 54, and the other end connected in series with the coil 2 of the three-way valve 22.
4 and the coil 56 of the relay switch 54. 58 is a delay relay connected between the reel switch 54 and the coil 20 of the opening/closing valve 18, and 60 is a delay relay connected between the output shaft of the delay relay 58 and the coil 24 of the three-way valve 22. 62 is a cold start switch 40
A pilot lamp 64 lights up to indicate a cold start when the cold start switch 40 is closed, or the three switches 42, the exhaust brake switch 42, the accelerator micro switch 44, and the clutch micro switch 46 are closed. A pilot lamp lights up to indicate that the exhaust brake is activated.
A pilot lamp 66 lights up when the delay relay 58 is energized to indicate warm-up. In addition, in the figure, 68, 70, 72, 74 and 76 are rectifiers, respectively. Next, the operation of this device will be explained. First, when the switches 40, 42, and 48 are not operated, the coil 24 of the three-way valve 22 is not energized, so the actuator 1
The chamber 10 of No. 2 is communicated with the atmosphere, the movable wall 9 is held at the position indicated by the two-dot chain line 9b in the figure by the biasing force of the return spring 17, and the exhaust valve 6 also completely blocks the exhaust pipe 2. do not. Second, when only the cold start switch 40 is closed, the coil 24 of the three-way valve 22 is energized, causing the three-way valve 22 to communicate between the vacuum source 16 and the chamber 10 of the actuator 8, and to 14 to the atmosphere, and this chamber 10
The negative pressure within the movable wall 9 is increased and the spring 17
The exhaust valve 6 is lowered to the position shown by the two-dot chain line 9a against the urging force of the exhaust valve 6, and the exhaust valve 6 is also lowered accordingly, thereby completely or almost completely closing the exhaust pipe 2. Since the position of the exhaust valve 6 is the same as the exhaust brake operating position, the pilot lamp 62 indicating cold start and the pilot lamp 64 indicating exhaust brake operation are lit at this time. Thirdly, when only the exhaust brake switch 42 is closed, if the accelerator micro switch 44 and the clutch micro switch 46 are closed, that is, if the accelerator pedal and the clutch pedal are not depressed, the coil of the three-way valve 22 24 is energized, and the exhaust pipe 2 is completely closed or almost completely closed by the exhaust valve 6 in the same manner as in the above case. Note that at this time, only the pilot lamp 64 indicating the exhaust brake operation is lit. Fourth, when only the warm-up switch 48 is closed, the relay switch 54 remains closed because its coil 56 is not energized, and on condition that the water temperature switch 50 and the rotational speed switch 52 are closed, i.e., the cooling The delay relay 58 is energized on condition that the water temperature is below the set value and the engine speed is below the set value. Then, after a set time (for example, 2 seconds), the coil 20 of the opening/closing valve 18 is energized to close the passage 14.
After a further set period of time (for example, 2 seconds), the three-way valve 22 has its coil 24 energized and the passage 1
The vacuum source 16 and the chamber 10 are connected to each other by an orifice 34 and a regulator valve 26.
Communication will be made only through the . Therefore, after the coil 24 of the three-way valve 22 is energized, the negative pressure in the chamber 10 of the actuator 8 is gradually increased, and the movable wall 9 also begins to gradually descend against the biasing force of the spring 17. The negative pressure in the chamber 30 of the regulator valve 26 is also gradually increased, and the movable wall 28 is also gradually moved in the direction of closing the valve. When the regulator 26 is completely closed, the movable wall 9 of the actuator 8 also stops descending.
As shown by the solid line in the figure, the exhaust valve 6 is stopped at a warm-up device whose opening is slightly larger than the exhaust brake operating position. At this time, the pilot lamp 66 indicating warm-up is turned on. In this manner, when the engine speed becomes greater than the set value while the exhaust valve 6 is held by the warm-up device, the speed switch 52 is opened and the delay relay 58 is no longer energized. With the power supply to the delay relay 58 being stopped, the opening/closing valve 18
At the same time, the power supply to the coil 20 of the three-way valve 22 is stopped via the delay relay 60, and the passage 14 is opened to the atmosphere via the opening/closing valve 18 and the three-way valve 22. communicated. As a result, the pressure inside the chamber 10 of the actuator 8 changes to atmospheric pressure, and the movable wall 9
is raised to the position shown by the two-dot chain line 9b by the biasing force of the spring 17, and the exhaust valve 6 no longer closes the exhaust pipe 2. If the warm-up position is set so that a warm-up effect can be obtained even when the engine rotates at low speed, if the warm-up position is constant, the exhaust valve 6 will block the exhaust pipe 2 too much during high-speed rotation, reducing exhaust efficiency. However, as mentioned above, when the engine speed is higher than the set rotation speed, the exhaust valve 6 stops blocking the exhaust pipe 2, thereby preventing the generation of black smoke during high straight rotation. be done. Here, a case will be described in which the warm-up switch 48 and the cold start switch 40 or the exhaust brake switch 42 are closed at the same time. In this case, since the coil 56 of the relay switch 54 is energized and the relay switch 54 is opened, the coil 20 of the opening/closing valve 18 is not energized at all, and priority is given to the operation of the cold start switch 40 or exhaust brake switch 42. Coil 2 of way valve 22
4 is energized and the actuator 8 moves its movable wall 9
is lowered to the position shown by the two-dot chain line 9a, and the exhaust valve 6 is moved to the fully closed position or substantially fully closed position of the exhaust pipe 2. The table below shows the relationship between the operation of each switch and the operation of the exhaust valve under each operating condition, including the cases explained above.

[Table] Next, the effects of the device of this embodiment will be explained. In this device, the exhaust valve 6 for the exhaust brake and its actuator 8 are configured to partially open the exhaust pipe to obtain an engine warming effect, so it is exclusively used for warming up the exhaust pipe with the exhaust pipe partially opened. weight, compared to one with a valve of
This is effective in terms of space and cost. Moreover, the movement of the exhaust valve 6 to the warm-up position is performed by adjusting the fluid pressure acting on the actuator 8 using the on-off valve 18, the 3-way valve 22, and the regulator valve 26 as fluid pressure regulating devices. Therefore, there is no need for a separate stopper and a cable or actuator for driving the stopper, which were required in the conventional device, and this has the effect of not only reducing the number of parts but also being very advantageous in terms of space. . Furthermore, when the warm-up switch 48 is closed due to reasons such as wanting to improve the effectiveness of the heater while driving in a cold region, the exhaust valve 6 is moved from its fully open position to the warm-up position by the action of the orifice 34. Since this is done in a loose manner, drivability is hardly impaired.
Furthermore, even when the warm-up switch 48 is closed, if the exhaust brake switch 42 is closed,
Since the relay switch 54 is immediately opened and the on-off valve 18 is opened, it is possible to prevent the control performance of the vehicle from deteriorating. Further, when the exhaust valve 6 is in the warm-up position due to the closing of the warm-up switch 48, if the engine speed is in a high-speed rotation range exceeding the set value, the opening degree of the exhaust valve 6 is fully opened. Therefore, it is possible to prevent the generation of black smoke due to a decrease in exhaust efficiency. Although the exhaust valve 6 is of the slide type in the above embodiment, it is also possible to adopt a butterfly type valve if necessary.

[Brief explanation of the drawing]

The drawings are explanatory diagrams showing an entire embodiment of the present invention. 2...Exhaust pipe, 6...Exhaust valve, 8...Actuator, 48...Warm-up switch.

Claims (1)

[Scope of utility model registration request] It has an exhaust brake valve that can open and close the exhaust pipe of the engine, and a movable wall that is connected to the exhaust brake valve and is biased by a spring. a hydraulic actuator that opens and closes the exhaust brake valve; a fluid pressure supply source that generates the fluid pressure; and a fluid pressure supply source that adjusts the fluid pressure of the fluid pressure supply source and supplies it to the fluid actuator to exhaust the air. a fluid pressure regulating device that maintains the brake valve at either a first predetermined opening of fully closed or nearly fully closed, a second predetermined opening greater than the first predetermined opening and smaller than fully open, and fully open; and an opening degree changing section that fully opens the exhaust brake valve when the engine speed is in a high speed rotation range greater than the predetermined rotation speed while the exhaust brake valve is held at the second predetermined opening degree. A distinctive engine warm-up device.