JP5239927B2 - Brake device and engine intake control device - Google Patents

Description

  The present invention relates to a braking device and an intake control device for an engine having the braking device.

  2. Description of the Related Art Conventionally, a braking device including a pneumatic booster that generates an assist force that assists brake pedal operation using intake negative pressure is widely known.

  Patent Document 1 discloses a braking device including a booster having an ejector that generates a negative pressure by an intake venturi effect and a control valve that controls an intake air flow that passes through a throttle portion of the ejector. Yes. In this braking device, negative pressure is secured in the negative pressure chamber of the booster by controlling the control valve.

JP 2002-212385 A

  However, in the brake device described in Patent Document 1, it is necessary to provide an ejector and a control valve separately from the intake passage, and the configuration becomes complicated. In particular, the control valve has a large number of parts and a complicated structure.

  In addition, when foreign matter is mixed into the intake air, there is a possibility that the throttle portion of the ejector may be clogged, which may make it difficult for negative pressure to be generated.

  Therefore, the present invention has been made paying attention to such a problem, and has a simple configuration and can secure a sufficient negative pressure in the negative pressure chamber of the booster, and the braking device. It is an object to provide an intake control device for an engine equipped with

  The present invention solves the above problems by the following means. In addition, in order to make an understanding easy, although the code | symbol corresponding to embodiment of this invention is attached | subjected, it is not limited to this.

  According to the present invention, in the braking device (100) having the booster (30) for assisting the operation of the brake pedal using the negative pressure in the negative pressure chamber (32), the intake air is exposed so as to face the intake passage (60). A frame portion (41) formed in the passage (60), a throttle portion (42) that slides in the frame portion (41) and changes the intake flow area of the intake passage (60), and a throttle portion (42) The first air chamber (45) and the second air chamber (46) are separated by the urging means (47) for urging the air to be pushed out to the intake passage side, and the frame portion (41) and the throttle portion (42). ), And connected to the bottom surface (41A) of the frame portion (41) and the bottom surface (42B) of the throttle portion (42) and formed to expand and contract depending on the position of the throttle portion (42) ( 44), a first negative pressure passage (51) communicating the first air chamber (45) and the negative pressure chamber (32), and a second A second negative pressure passage (52) communicating with the air chamber (46) and the negative pressure chamber (32) and a throttle portion (42) are formed and opened to the first air chamber (45) and the intake passage (60). A communication passage (42A), and when the negative pressure in the negative pressure chamber (32) is reduced, the urging means (47) pushes the throttle portion (42) toward the intake passage (60), thereby opening the throttle portion (42). By increasing the flow rate of the intake air passing therethrough, the air in the negative pressure chamber (32) flows out into the intake passage (60) via the communication passage (42A) so that the negative pressure in the negative pressure chamber (32) increases. When the negative pressure in the negative pressure chamber (32) increases, the throttle part (42) is accommodated in the frame part (41) against the biasing means (47) by the negative pressure in the second air chamber (46). It is characterized by.

  According to the present invention, it is a configuration that generates the necessary negative pressure in the negative pressure chamber of the booster by automatically changing the position of the throttle portion by the biasing means and the negative pressure in the second air chamber, The number of parts is smaller than that of the conventional method, that is, the configuration can be simplified.

  Further, since the throttle portion is accommodated in the frame portion when the negative pressure in the second air chamber increases, foreign matter may be clogged between the throttle portion and the intake passage even when foreign matter is mixed into the intake air. Absent.

It is a schematic block diagram of the braking device for vehicles in a 1st embodiment. It is a figure explaining operation | movement of the negative pressure generator of a braking device. It is a flowchart explaining the main routine of throttle control. It is a figure which shows a throttle opening-intake amount characteristic curve. It is a schematic block diagram of the braking device of 2nd Embodiment.

(First embodiment)
The first embodiment of the present invention will be described below with reference to FIGS.

  FIG. 1 is a schematic configuration diagram of a braking device 100 for a vehicle.

  The braking device 100 includes a brake pedal 10, a master cylinder 20, a booster 30, and a negative pressure generator 40.

  The brake pedal 10 is provided in the vehicle interior and is operated by the driver.

  The master cylinder 20 is a device that pumps brake oil to the foil cinder. The brake oil pressure changes according to the depression amount of the brake pedal 10.

  The booster 30 is disposed between the brake pedal 10 and the master cylinder 20. The booster 30 includes a diaphragm 33 that divides the interior into a variable pressure chamber 31 and a negative pressure chamber 32, and a push rod 34.

  The variable pressure chamber 31 communicates with the outside via the atmospheric valve 35.

  The negative pressure chamber 32 communicates with the negative pressure generator 40 via the first negative pressure passage 51 and the second negative pressure passage 52. A negative pressure is introduced into the negative pressure chamber 32 from the negative pressure generator 40. The negative pressure chamber 32 communicates with the variable pressure chamber 31 via a vacuum valve 36 provided on the outer periphery of the push rod.

  The push rod 34 penetrates the booster 30. One end of the push rod 34 is connected to the brake pedal 10, and the other end is connected to the piston of the master cylinder 20. The push rod 34 is connected to the diaphragm 33 via the connecting portion 34A.

  When the brake pedal 10 is not depressed, the atmospheric valve 35 of the booster 30 is closed, the communication between the variable pressure chamber 31 and the outside is cut off, the vacuum valve 36 is opened, and the negative pressure from the variable pressure chamber 31 is negative. The pressure chamber 32 communicates. Therefore, the pressure in the variable pressure chamber 31 and the pressure in the negative pressure chamber 32 are the same negative pressure.

  On the other hand, when the brake pedal 10 is depressed, the push rod 34 moves to the left side in the figure, the vacuum valve 36 is closed, and the communication between the variable pressure chamber 31 and the negative pressure chamber 32 is cut off. The atmosphere valve 35 is opened and the atmosphere is introduced into the variable pressure chamber 31. Therefore, the pressure in the variable pressure chamber 31 becomes atmospheric pressure, and the pressure in the negative pressure chamber 32 remains the same negative pressure as before the brake pedal 10 was depressed. As a result, a pressure difference is generated between the variable pressure chamber 31 and the negative pressure chamber 32, and this differential pressure acts on the diaphragm 33 and becomes an assist force when the push rod 34 is moved to the left side in the drawing.

  Thus, the booster 30 assists the driver's brake pedal operation using the negative pressure from the negative pressure generator 40 as a boost source.

  The negative pressure generator 40 is provided in an intake passage 60 through which intake air supplied to the engine flows. The negative pressure generation device 40 is a device that generates a negative pressure according to the negative pressure state of the negative pressure chamber 32 of the booster 30, and includes a frame portion 41 and a throttle portion 42.

  The frame portion 41 has a cylindrical shape and is formed to bulge into the intake passage 60 so as to face the inside of the intake passage. The frame portion 41 is formed so that the axis is orthogonal to the intake passage axial direction.

  The throttle part 42 has a substantially cylindrical shape and is provided to be slidable with respect to the frame part 41. The throttle portion 42 moves according to the negative pressure state of the negative pressure chamber 32 of the booster 30 and changes the intake flow area of the intake passage 60. A seal member 43 is provided on the outer periphery of the throttle portion 42, and the seal member 43 seals between the outer periphery of the throttle portion 42 and the inner periphery of the frame portion 41.

  A communication passage 42 </ b> A is formed in the throttle portion 42. One end of the communication path 42A opens to the bottom surface 42B of the throttle section 42, and the other end opens to the tip surface 42C.

  The inner side of the frame portion 41 is separated into a first air chamber 45 and a second air chamber 46 by a partition wall 44. The first air chamber 45 and the second air chamber 46 expand and contract as the throttle unit 42 moves.

  The partition wall 44 is formed in a cylindrical shape, and one end is connected to the bottom surface 41 </ b> A of the frame portion 41 and the other end is connected to the bottom surface 42 </ b> B of the throttle portion 42. The side part of the partition 44 is formed in a bellows shape along the axial direction so that the partition 44 can expand and contract in the moving direction of the throttle part 42.

  Within the second air chamber 46, a compressed spring 47 is disposed between the bottom surface 41A of the frame portion 41 and the bottom surface 42B of the throttle portion 42. The spring 47 biases the throttle part 42 so as to push it down to the intake passage 60 side.

  The first air chamber 45 communicates with the intake passage 60 via the communication passage 42 </ b> A of the throttle portion 42 and also communicates with the negative pressure chamber 32 of the booster 30 via the first negative pressure passage 51. The first negative pressure passage 51 is provided with a check valve 51A that allows only air flow from the negative pressure chamber 32 side to the first air chamber 45 side.

  The second air chamber communicates with the negative pressure chamber 32 of the booster 30 via the second negative pressure passage 52.

  An air flow meter 61 and a throttle valve 62 are provided in the intake passage 60 on the downstream side of the negative pressure generator 40 configured as described above.

  The air flow meter 61 is installed in the intake passage 60 on the downstream side of the negative pressure generator 40. The air flow meter 61 is a hot-wire air flow meter, and detects the intake air flow rate of the intake air supplied to the engine.

  The throttle valve 62 is installed in the intake passage 60 on the downstream side of the air flow meter 61. The throttle valve 62 adjusts the amount of intake air introduced into the engine by changing the intake flow area of the intake passage 60.

  The throttle opening degree of the throttle valve 62 is controlled by the controller 70.

  The controller 70 includes a microcomputer having a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), and an input / output interface (I / O interface).

  Detection data from an air flow meter 61 and a throttle opening sensor 63 that detects the throttle opening are input to the controller 70 as signals. The controller 70 controls the throttle opening of the throttle valve 62 based on these input signals.

  In the braking device 100, when the brake pedal 10 is depressed, atmospheric pressure is introduced into the variable pressure chamber 31 of the booster 30, so that the negative pressure in the negative pressure chamber 32 decreases each time the brake pedal 10 is operated. When the negative pressure in the negative pressure chamber 32 decreases, the assist force in the booster 30 decreases. However, in the braking device 100, a negative pressure is generated by the negative pressure generator 40 according to the pressure state in the negative pressure chamber 32. Therefore, the assist force can be prevented from decreasing.

  The operation of the negative pressure generator 40 will be described with reference to FIG. 2A shows a case where the negative pressure in the negative pressure chamber 32 of the booster 30 is reduced, and FIG. 2B shows a sufficiently large negative pressure in the negative pressure chamber 32 of the booster 30. The case where is secured.

  When the brake pedal 10 is operated and the negative pressure in the negative pressure chamber 32 of the booster 30 is reduced, the throttle portion 42 of the negative pressure generator 40 is caused by the reaction force of the spring 47 as shown in FIG. It is pushed out to the intake passage 60 side. When the first air chamber 45 and the second air chamber 46 are enlarged and the throttle portion 42 is pushed out, the intake flow area of the intake passage 60 is reduced. As a result, the flow velocity of the intake air passing through the distal end surface 42C of the throttle portion 42 is increased, and a negative pressure is generated in the opening portion of the communication passage 42A on the distal end surface 42C side. Thereby, the air inside the first air chamber 45, the second air chamber 46, and the negative pressure chamber 32 of the booster 30 is sucked out to the intake passage 60 side, and the negative pressure in the negative pressure chamber 32 of the booster 30 is obtained. Becomes larger. Since the first negative pressure passage 51 is provided with the check valve 51A, the negative pressure chamber 32 is maintained in a negative pressure state.

  When the negative pressure in the negative pressure chamber 32 of the booster 30 increases, the negative pressure in the second air chamber 46 of the negative pressure generator 40 also increases. When the negative pressure in the second air chamber 46 increases, the throttle portion 42 is drawn into the frame portion 41 against the reaction force of the spring 47 as shown in FIG. When the first air chamber 45 and the second air chamber 46 are reduced and the throttle portion 42 is accommodated in the frame portion 41, the intake air flow area of the intake passage 60 increases, so that the intake flow is inhibited by the throttle portion 42. It is suppressed. In a state where the entire throttle portion 42 is accommodated in the frame portion 41, almost no negative pressure is generated in the opening portion of the communication passage 42A on the distal end surface 42C side of the throttle portion 42.

  In the braking device 100, when the negative pressure in the negative pressure chamber 32 of the booster 30 is reduced, the negative pressure is automatically generated by the negative pressure generator 40. Therefore, the assist force of the booster 30 is not reduced. Thus, the negative pressure chamber 32 can be maintained in a negative pressure state.

  By the way, in the engine provided with the braking device 100, the throttle valve 62 is provided in the intake passage 60 on the downstream side of the negative pressure generating device 40. Therefore, even if the throttle opening is controlled to a constant opening, the amount of intake air supplied to the engine changes according to the position of the throttle portion 42 of the negative pressure generator 40. That is, when the throttle portion 42 protrudes toward the intake passage 60, the intake flow is hindered, the intake amount is reduced, and the output performance of the engine is deteriorated.

  Therefore, in the present embodiment, when the throttle portion 42 protrudes toward the intake passage 60, the throttle opening is increased to suppress deterioration in engine output performance.

  FIG. 3 is a flowchart illustrating a main routine of throttle control executed by the controller 70. This main routine is repeatedly executed at regular intervals, for example, 10 ms intervals during engine operation.

  In step 101, the controller 70 calculates an intake air amount detection value Qv and a throttle opening detection value THv, and executes the process of step S102.

  The intake air amount detection value Qv is calculated based on the detection value of the air flow meter 61. The throttle opening detection value THv is calculated based on the detection value of the throttle opening sensor 63.

  In step S102, the controller 70 calculates an intake air amount (hereinafter referred to as “maximum intake air amount”) Qmax when all the throttle portions 42 are accommodated in the frame portion 41 based on the throttle opening detection value THv.

  As shown in FIG. 4, the controller 70 stores a throttle opening / intake amount characteristic line for each engine operating state. A line A is a throttle opening / intake amount characteristic line when all the throttle portions 42 are accommodated in the frame portion 41, and the maximum intake amount Qmax is calculated based on the line A.

  The controller 70 also stores a throttle opening / intake amount characteristic line when the throttle portion 42 protrudes toward the intake passage as shown by lines B to D. A line D is an intake air amount characteristic line when the throttle portion 42 protrudes most toward the intake passage.

  Returning to FIG. 3, in step S103, the controller 70 determines whether or not the intake air amount detection value Qv is smaller than the maximum intake air amount Qmax.

  When the intake air amount detection value Qv is smaller than the maximum intake air amount Qmax, the controller 70 determines that the throttle portion 42 protrudes toward the intake passage 60 and executes the process of step S104. In other cases, the controller 70 ends the process without correcting the throttle opening.

  In step S104, the controller 70 increases the throttle opening so that the intake air amount becomes the maximum intake air amount Qmax.

  That is, as shown in FIG. 4, an intake air amount characteristic line at the current throttle position of the negative pressure generator 40 is selected from the intake air amount detection value Qv and the throttle opening degree detection value THv, and the intake air amount in the intake air amount characteristic line is selected. Is increased so that the maximum intake amount Qmax is obtained. When the throttle portion 42 of the negative pressure generator 40 protrudes toward the intake passage 60, the throttle opening is increased, so that a reduction in intake air amount can be suppressed.

  As described above, in the present embodiment, the following effects can be obtained.

  In the negative pressure generating device 40 of the braking device 100, when the negative pressure in the negative pressure chamber 32 of the booster 30 decreases, the throttle portion 42 is pushed out toward the intake passage 60 by the reaction force of the spring 47, and the throttle portion 42. Since the flow velocity of the intake air passing through the front end surface 42C of the cylinder is increased, a negative pressure can be generated at the opening portion of the communication passage 42A, and the negative pressure in the negative pressure chamber 32 can be increased. When the negative pressure in the negative pressure chamber 32 of the booster 30 increases and the negative pressure in the second air chamber 46 of the negative pressure generator 40 increases, the throttle portion 42 resists the reaction force of the spring 47. Since it is accommodated in the frame part 41, it can suppress that the throttle part 42 inhibits an intake flow.

  The negative pressure generating device 40 is configured to generate necessary negative pressure by automatically changing the position of the throttle portion 42 by the spring 47 and the negative pressure in the second air chamber 46, and is less than the conventional method. The number of parts, that is, a simple configuration can be obtained. Moreover, since the throttle part 42 of the negative pressure generator 40 is accommodated in the frame part 41 when the negative pressure in the second air chamber 46 increases, the throttle part 42 even when foreign matter is mixed in the intake air. Foreign matter is not clogged between the intake passage 60 and the intake passage 60.

  If the negative pressure generator 40 is provided on the downstream side of the air flow meter 61, the measurement accuracy of the air flow meter 61 deteriorates due to the air sucked from the negative pressure chamber 32 of the booster 30 when negative pressure is generated. In the present embodiment, since the air flow meter 61 is installed on the downstream side of the negative pressure generator 40, the deterioration of the measurement accuracy of the air flow meter 61 can be suppressed.

  In an intake control device for an engine having a braking device 100 having a negative pressure generating device 40 provided in an intake passage 60 upstream of the air flow meter 61 and the throttle valve 62, the throttle portion 42 is pushed out to the intake passage 60 side. Sometimes, the slot opening is controlled based on the intake air amount detection value Qv and the throttle opening detection value THv, so that the reduction of the intake air amount when negative pressure occurs is suppressed and the deterioration of the engine output performance is suppressed. be able to.

(Second Embodiment)
FIG. 5 is a schematic configuration diagram of the braking device 100 of the second embodiment.

  The braking device 100 of the second embodiment has substantially the same configuration as that of the first embodiment, but differs in the configuration of the frame portion 41 and the throttle portion 42 of the negative pressure generating device 40. Hereinafter, the difference will be mainly described.

  As shown in FIG. 5, a communication pipe 41 </ b> B is formed in the frame part 41 of the negative pressure generating device 40 in the moving direction of the throttle part 42.

  The communication pipe 41 </ b> B is formed at the frame portion 41 so that one end is connected to the first negative pressure passage 51, and the other end is inserted into the communication passage 42 </ b> A of the throttle portion 42. A seal member 48 is provided on the outer periphery on the other end side of the communication tube 41B, and the seal member 48 seals between the outer periphery of the communication tube 41B and the inner periphery of the communication passage 42A. Therefore, the negative pressure chamber 32 of the booster 30 communicates with the intake passage 60 via the first negative pressure passage 51, the communication pipe 41B, and the communication passage 42A.

  Even if the frame portion 41 and the throttle portion 42 of the negative pressure generating device 40 of the braking device 100 are configured as described above, the same effects as in the first embodiment can be obtained.

  In the negative pressure generating device 40, the throttle portion 42 slides along the side wall of the frame portion 41 and the communication pipe 41B, so that the throttle portion 42 can be smoothly slid in the moving direction.

  Further, in the negative pressure generating device 40, since the seal member 48 is provided on the outer periphery of the communication pipe 41B, the sealing range can be narrowed compared to the case where the seal member is provided around the throttle portion as in the first embodiment. The sealing performance between the communication pipe 41B and the communication passage 42A can be enhanced. This makes it possible to more efficiently suck out the air in the negative pressure chamber 32 of the booster 30 when negative pressure is generated.

  Note that the present invention is not limited to the above-described embodiment, and it is obvious that various modifications can be made within the scope of the technical idea.

DESCRIPTION OF SYMBOLS 100 Braking device 10 Brake pedal 20 Master cylinder 30 Booster 31 Transformer chamber 32 Negative pressure chamber 40 Negative pressure generator 41 Frame part 41B Communication pipe 42 Restriction part 42A Communication path 43, 48 Seal member 44 Partition 45 First air chamber 46 Second air chamber 47 Spring (biasing means)
51 First negative pressure passage 51A Check valve 52 Second negative pressure passage 60 Intake passage 61 Air flow meter 62 Throttle valve 70 Controller

Claims (6)

In the braking device having a booster that assists the brake pedal operation using the negative pressure in the negative pressure chamber,
A frame portion formed in the intake passage so as to face the inside of the intake passage;
A throttle portion that slides within the frame portion and changes the intake air flow area of the intake passage;
Urging means for urging the throttle portion to push out toward the intake passage;
A space separated by the frame portion and the throttle portion is partitioned into a first air chamber and a second air chamber, and connected to the bottom surface of the frame portion and the bottom surface of the throttle portion according to the position of the throttle portion. A partition wall formed to expand and contract;
A first negative pressure passage communicating the first air chamber and the negative pressure chamber;
A second negative pressure passage communicating the second air chamber and the negative pressure chamber;
A communication passage formed in the throttle portion and opening to the first air chamber and the intake passage;
When the negative pressure in the negative pressure chamber decreases, the urging means pushes the throttle portion toward the intake passage so that the flow rate of the intake air passing through the throttle portion is increased so that the negative pressure in the negative pressure chamber increases. The air in the negative pressure chamber is caused to flow out to the intake passage through the communication passage, and when the negative pressure in the negative pressure chamber increases, the throttle portion is opposed to the biasing means by the negative pressure in the second air chamber. Accommodate in the frame,
A braking device characterized by that. One end of the frame portion is connected to the first negative pressure passage and the other end is inserted into the communication passage so that air flowing from the negative pressure chamber to the first air chamber side flows through the communication passage. A communication pipe is formed,
The braking device according to claim 1. The first negative pressure passage is provided with a check valve that allows only air flow from the negative pressure chamber to the first air chamber.
The braking device according to claim 1, wherein the braking device is provided. An air flow meter is provided in the intake passage on the downstream side of the frame portion.
The braking device according to any one of claims 1 to 3, wherein: A throttle valve is provided in the intake passage on the downstream side of the air flow meter.
The braking device according to claim 4. In an intake control device for an engine comprising the braking device according to claim 5,
Throttle control means for increasing control of the throttle valve opening based on the detected throttle valve opening value and the detected intake air amount when the throttle portion is pushed out to the intake passage side by the biasing means;
An intake control device for an engine.

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