JP2001090556A - Throttle device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive and compact throttle device superior in responsiveness of opening control in trouble. SOLUTION: The opening of a valve member is controlled via a intermediate gear 28 and a throttle gear 20 with the rotation of a motor 30 and a suction flow rate is regulated accordingly. When the motor 30 is normally operated, a spool valve member 61 is energized with the energization of a spring 62 and a movable member 70 is subjected at its head 72 to cooling water pressure from a rod 71, whereby most of the rod 71 is stored in a fluid passage 75. When trouble such as breakage occurs in the motor 30, a current is supplied to an electromagnetic drive portion of the spool valve 60 for attaching the spool valve member 61 against the energizing force of the spring 62. The cooling water pressure is applied from the counter rod side of the head 72 to the movable member 70 to cause the rod 71 to largely extending from the fluid passage 75, whereby a throttle gear 20 together with a locking member 25 is rotated to be closed and the opening of the throttle is set close to a fully closed position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal combustion engine (hereinafter referred to as "internal combustion engine").
The present invention relates to a throttle device for adjusting an intake flow rate of an “internal combustion engine”.

[0002]

2. Description of the Related Art In a throttle device in which a disk-shaped valve member for adjusting an intake flow rate flowing through an intake passage by rotating is driven by an electric drive means such as a motor, the operation of the motor is stopped due to disconnection of the motor or the like. However, various configurations have been considered in which the throttle opening is set to a predetermined position, for example, in the vicinity of a fully closed position, in order to enable the safe limp-home running. For example, by providing a return spring that urges the valve member in the closing direction and disposing a stopper that locks the valve member that rotates in the closing direction near the fully closed position, the motor cannot drive the valve member. Also, the throttle opening is set near the fully closed position to enable limp-home running. If it is not necessary to perform the limp-home running, the stopper may be provided at the fully closed position. However, since the urging force of the return spring for urging the valve member in the closing direction is constantly applied to the valve member, a large driving force is required for the motor to drive the valve member against the urging force of the return spring. Therefore, it is difficult to reduce the size of the motor.

To solve this problem, Japanese Patent Application Laid-Open No. Hei 4-246
In the throttle device disclosed in Japanese Patent Publication No. 246, a reset spring for defining a throttle opening is formed of a shape memory metal. When the drive current is supplied to the motor and the motor is operating, the urging force of the reset spring does not act on the valve member. When the supply line that supplies the drive current to the motor is disconnected, the current is supplied to the reset spring by the operation of the switching relay, and the shape of the reset spring changes due to an increase in the temperature of the reset spring. The reset spring rotates the regulating member that regulates the opening of the valve member by deforming, and sets the throttle opening near the fully closed position. Since the biasing force of the reset spring is not applied to the valve member during operation of the motor, the driving force of the motor can be reduced and the size of the motor can be reduced.

[0004]

However, since the shape of the reset spring formed of the shape memory metal changes depending on the temperature, the time required for the reset spring to be deformed and the throttle opening to be set near the fully closed position is reduced. There is a delay. Then, the vehicle may travel until the throttle opening is set near the fully closed position. Further, in order to form the reset spring for setting the vicinity of the fully closed position with high accuracy by using the shape memory metal, there is a problem that the manufacturing cost is increased. An object of the present invention is to provide an inexpensive and compact throttle device which has excellent responsiveness of opening adjustment when a failure occurs.

[0005]

According to the throttle device of the present invention, during the operation of the electric drive means for driving the valve member which adjusts the flow rate of the intake air flowing through the intake passage by rotating. A fluid pressure is applied to the movable member in the direction opposite to the direction in which the valve member is biased to the predetermined throttle opening position, and the movable member is biased to the predetermined throttle opening position while the electric drive means is stopped. Apply fluid pressure to When the electric drive means is operating, the fluid pressure urging the valve member is not applied to the movable member, so that it is not necessary to drive the valve member against the fluid pressure applied to the movable member. Therefore, the driving force of the electric driving means can be reduced and the electric driving means can be downsized, so that the throttle device can be made smaller. Further, the manufacturing cost of the electric drive means is reduced.

Further, since only the switching means is operated to reverse the direction of the fluid pressure applied to the movable member, the switching means is operated after the electric drive means cannot drive the valve member due to disconnection or the like, and the movable member is moved to a predetermined position. There is almost no time delay until the valve member is urged to the throttle opening, and the response is excellent. According to the throttle device of the second aspect of the present invention, since the cooling water used by the engine is used as the drive fluid for the movable member, it is not necessary to newly provide a fluid drive source for the movable member.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a first embodiment of the present invention; (First Embodiment) FIGS. 1, 2 and 3 show a first embodiment of the present invention. The throttle device 1 shown in FIG. 3 electrically controls a throttle opening in accordance with engine operating conditions such as an accelerator opening, an engine speed, an engine load, and a water temperature, so that intake air flowing through an intake passage 11 a formed in a throttle body 11 is provided. It adjusts the flow rate. The state shown in FIG. 3 is a fully opened state of the throttle device 1.

The throttle shaft 12 is rotatably supported by the throttle body 11 via bearings 15 and 116 provided at both ends of the throttle shaft 12. Valve member 13
Is formed in a disc shape, and is fixed to the throttle shaft 12 by screws 14. Throttle shaft 12 and valve member 1
3 and rotates together.

As shown in FIG. 1, the throttle gear 20 is formed in a semi-disc shape, and the throttle shaft 1 is
2 is fixed so as not to rotate relatively. The locking member 25 is formed in a circular shape, and is fitted to the throttle shaft 12 between the throttle gear 20 and the bearing 15 as shown in FIG. The locking member 25 is rotatable relative to the throttle shaft 12. The locking member 25 has a contact portion 25a protruding toward the throttle gear 20 in the axial direction, and a protruding portion 25b protruding radially outward. The spring 26 has one end fixed to the throttle gear 20 and the other end fixed to the locking member 25. The biasing force of the spring 26 acts in a direction in which the open end 21 of the throttle gear 20 and the contact portion 25a of the locking member 25 approach in FIG. Due to the urging force of the spring 26, the open end 21 of the throttle gear 20 and the contact portion 25a of the locking member 25 are normally in contact with each other. In FIG. 1, the opening direction is clockwise. The position where the projection 25b of the locking member 25 is locked by the stopper 51 formed on the throttle body 11 is near the fully closed position slightly opened from the fully closed position. When a driving force in the closing direction is further applied to the throttle gear 20 from near the fully closed position as a predetermined throttle opening, the throttle gear 20 rotates in the closing direction against the urging force of the spring 26, and the throttle side of the throttle gear 20 closes. The end 22 is locked by a not-shown fully closed stopper. The position of the fully closed stopper is the fully closed position of the throttle opening. Since the angular width between the fully closed position defined by the stopper 51 and the fully closed position defined by the fully closed stopper (not shown) is narrow, the throttle is moved from near the fully closed position to the fully closed position against the urging force of the spring 26. The driving force of the motor 30 for driving the gear 20 is small. The intermediate gear 28 has small-diameter gear teeth 28a and large-diameter gear teeth 28b. The small-diameter gear teeth 28a mesh with the gear teeth 20a of the throttle gear 20, and the large-diameter gear teeth 28b mesh with the gear teeth 32a of the motor gear 32 of the motor 30.

The motor 30 as an electric drive means is, for example, a DC motor, and is attached to the throttle body 11. The gear teeth 32 a of the motor gear 32 that rotates together with the rotation shaft 31 of the motor 30 mesh with the large-diameter gear teeth 28 b of the intermediate gear 28. As the motor 30 rotates, the driving force of the motor 30 is applied to the throttle shaft 12 and the valve member 13 via the intermediate gear 28 and the throttle gear 20, and the throttle opening is adjusted. The cover 50 covers each gear and the motor 30.

The rotation angle sensor 40 shown in FIG. 3 is attached to the throttle body 11 on the opposite side of the throttle gear 20 across the intake passage 11a. The contact member 41 fixed to the throttle shaft 12 by the bolt 18 is fitted with a lever member (not shown) of the rotation angle sensor 40. When the lever member (not shown) of the rotation angle sensor 40 rotates together with the contact member 41, the throttle opening is detected.

Spool valve 6 as switching means shown in FIG.
Reference numeral 0 denotes a spool valve member 61 supported reciprocally by the throttle body 11, a spring 62 for urging the spool valve member 61 in one direction, and a spring 62.
And an electromagnetic drive unit (not shown) for generating a magnetic force for attracting the spool valve member 61 against the urging force of. The spool valve member 61 is disposed over the inlet 75a and the outlet 75b of the fluid flow path 75. Engine cooling water flows through the fluid flow path 7
5 has been introduced. When no current is supplied to the electromagnetic drive unit, the spool valve member 61 is at the position shown in FIG.

The movable member 70 has a rod 71 as an arcuate shaft, and a head 72 as a pressure receiving part formed at one end of the rod 71. The opposite side of the rod 71 protrudes from the fluid channel 75. In FIG. 1, the throttle gear 20 and the locking member 25 are in the fully open position, and the rod 71 is not in contact with the protrusion 25 b of the locking member 25. Therefore, when the pressure of the cooling water is applied to the head 72 from the rod 71 side and the spool valve member 61 is at the position shown in FIG. 1, the locking member 25 and the throttle gear 20, that is, the throttle shaft 12 and the valve member 13 are movable. No urging force is received from the member 70.

The ECU 80 shown in FIG. 4 controls the drive current supplied to the motor 30 in accordance with the operating state of the engine, and adjusts the throttle opening. The motor detection circuit 81 detects whether there is no disconnection or the like in the motor 30, that is, whether or not the motor 30 is operating normally, and sends a detection signal to the ECU 80. The ECU 80 determines a detection signal sent from the motor detection circuit 81 and supplies a drive current to the motor 30.
The ECU 80 and the motor detection circuit 81 control the drive current supplied to the motor 30, and
Control means for controlling the current supplied to the electromagnetic drive unit.

Next, the operation of the throttle device 1 will be described. When the ECU 80 determines that there is no disconnection or the like in the motor 30 based on the detection signal sent from the motor detection circuit 81, that is, the motor 30 is operating normally,
0 is supplied with the drive current. Also, no current is supplied to the electromagnetic drive of the spool valve 60. The spool valve member 61 is at the position shown in FIG. Since the pressure of the cooling water is applied to the head 72 from the rod 71 side, the movable member 70 is at the position shown in FIG. 1, and the rod 71 does not abut on the protrusion 25 b of the locking member 25. Therefore,
The locking member 25 and the throttle gear 20, that is, the throttle shaft 12 and the valve member 13 receive no urging force from the rod 71. The ECU 80 controls an engine operation state such as an engine speed, an engine load, an accelerator opening, a water temperature, and the like, and a current value sent to the motor 30 in accordance with a detection signal of the rotation angle sensor 40 to adjust a throttle opening. From the fully open position shown in FIG. 1 until the projection 25b of the locking member 25 is locked by the stopper 51, the throttle gear 20 and the locking member 25 rotate integrally while abutting against the urging force of the spring 26. I do. When the value of the current supplied to the motor 30 is increased while the protrusion 25b is locked by the stopper 51 and the driving force applied to the throttle shaft 12 in the closing direction increases, the throttle gear 20 further resists the urging force of the spring 26. Rotate in the closing direction. Closed end 22 of throttle gear 20
The position where is locked by a not-shown fully closed stopper formed on the throttle body 11 is the fully closed position of the valve member 13. Since the angle between the stopper 51 and the not-shown fully closed stopper is small, the driving force of the motor 30 required to rotate the throttle gear 20 from near the fully closed position to the fully closed position against the urging force of the spring 26 is small.

When the ECU 80 determines that a failure such as a disconnection has occurred in the motor 30 based on a detection signal from the motor detection circuit 81, the ECU 80 stops controlling the motor 30 and supplies a current to the electromagnetic drive unit of the spool valve 60. . Then
The spool valve member 61 is sucked against the urging force of the spring 62 and moves to the position shown in FIG. Then, the pressure of the cooling water is applied to the movable member 70 from the side opposite to the rod of the head 72,
The rod 71 protrudes greatly from the fluid channel 75. The rod 71 comes into contact with the projection 25b of the locking member 25, and the locking member 2
5 urges the throttle gear 20 in the closing direction. By locking the projection 25b of the locking member 25 to the stopper 51, the throttle opening is set near the fully closed position.
In the vicinity of the fully closed position, normal traveling is difficult, but low-speed evacuation traveling is possible.

When the engine is stopped after retreating, the supply of current to the electromagnetic drive unit of the spool valve 60 is shut off, and the spool valve member 61 returns to the position shown in FIG. Therefore, when the disconnected motor 30 is replaced and the engine is started again, the throttle opening can be controlled between the fully open position and the fully closed position to perform normal traveling.

When the motor 30 is operating, the throttle shaft 12 does not receive an urging force from the movable member 70.
The motor 30 can adjust the throttle opening with a small driving force. Therefore, the size of the motor 30 is reduced and the size of the throttle device 1 is reduced. Further, since the driving force of the motor 30 required to rotate the throttle gear 20 from the vicinity of the fully closed position to the fully closed position against the urging force of the spring 26 is small, the motor 30 is downsized and the throttle device 1 is small. .

In the above-described embodiments showing the embodiment of the present invention, when the motor 30 is operating normally, the movable member 70 is moved in the direction opposite to the direction in which the valve member 13 is urged in the closing direction. Apply fluid pressure to Since there is no need to drive the valve member 13 against the urging force received from the movable member 70, the driving force of the motor 30 that drives the valve member 13 can be reduced. As a result, the manufacturing cost of the motor 30 is reduced, the physique is reduced, and the throttle device 1 is reduced in size. When the motor 30 stops operating due to disconnection or the like, the fluid pressure applied to the movable member 70 is reversed by supplying a current to the electromagnetic drive unit of the spool valve 60, and the movable member 70
Biases the valve member 13 in the closing direction. There is almost no time lag between detecting the failure of the motor 30 and operating the spool valve 60 to set the throttle opening near the fully closed position.
Excellent responsiveness. In the above embodiment, while the motor 30 is stopped, the movable member 70 sets the predetermined throttle opening near the fully closed position. On the other hand, the throttle gear 20
And the locking member 25 may be integrally formed, the spring 26 may be omitted, and the predetermined throttle opening may be set to the fully closed position. Further, the predetermined throttle opening position is not limited to the vicinity of the fully closed position and the fully closed position.

In a system that does not require evacuation, the locking member 25, the spring 26, and the stopper 51 can be eliminated. When an abnormality such as a failure occurs, the throttle gear 20 may be directly urged in the closing direction by the rod 71 and returned to the fully closed position. By doing so, the driving force of the motor 30 is reduced by the urging force of the spring 26, so that the motor 30 can be downsized. In the above embodiment, cooling water is used as the fluid drive source of the movable member 70, but hydraulic oil of a hydraulic control system may be used.

[Brief description of the drawings]

FIG. 1 is a diagram showing a throttle device according to an embodiment of the present invention in FIG.

FIG. 2 is a view from the same direction as FIG. 1 and shows the operation of the movable member when the motor fails.

FIG. 3 is a sectional view showing a throttle device according to an embodiment of the present invention.

FIG. 4 is a block diagram showing control means of the motor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Throttle device 11 Throttle body 12 Throttle shaft 13 Valve member 20 Throttle gear 25 Locking member 28 Intermediate gear 30 Motor (electric drive means) 60 Spool valve (switching means) 61 Spool valve member 70 Movable member 71 Rod (shaft) 72 Head (pressure receiving part) 75 Fluid flow path 80 ECU (control means) 81 Motor control circuit (control means)

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) F16K 31/04 F16K 31/04 Z 31/12 31/12 51/00 51/00 Z F term (reference) 3G065 CA34 CA38 DA05 DA15 GA05 GA09 GA10 GA41 GA46 HA06 HA12 HA15 HA21 HA22 JA09 JA11 KA02 3H052 AA02 BA25 BA32 BA35 EA16 3H056 AA05 BB01 BB45 CA04 CD01 DD03 GG05 GG18 3H062 AA03 AA15 BB10 BB33 CC10 DD01 EE07 AFFH

Claims (3)

[Claims] 1. A valve member for adjusting an intake flow rate flowing through an intake passage by rotating, an electric drive means for driving the valve member, and a movable member capable of urging the valve member to a predetermined throttle opening position. A switching unit for switching a direction of a fluid pressure applied to the movable member, wherein the switching unit applies a fluid to the movable member in a direction opposite to a direction in which the valve member is biased during operation of the electric drive unit. A throttle device which applies pressure and applies fluid pressure to said movable member in a direction for urging said valve member while said electric drive means is stopped. 2. The throttle device according to claim 1, wherein cooling water of an internal combustion engine is used as a driving fluid for said movable member. 3. The movable member has an arcuate shaft portion and a pressure receiving portion provided at one end of the shaft portion, and a part of the shaft portion and the pressure receiving portion are housed in a fluid flow path. The switching means has a spool valve member arranged over the inlet side and the outlet side of the fluid flow path, and the direction of the pressure applied by the fluid flowing from the inlet side to the pressure receiving portion is set to the 3. The throttle device according to claim 1, wherein the switching is performed by moving a spool valve member.