WO2008035670A1

WO2008035670A1 - Valve assembly

Info

Publication number: WO2008035670A1
Application number: PCT/JP2007/068081
Authority: WO
Inventors: Katsumi Nakamura; Shingo Iguchi; Masao Ida; Kiyohiro Shimokawa; Yusuke Adachi
Original assignee: Taiho Kogyo Co., Ltd.; Mitsuba Corp.; Hino Motors, Ltd.
Priority date: 2006-09-21
Filing date: 2007-09-18
Publication date: 2008-03-27
Also published as: JP2008075741A

Abstract

A valve assembly whose controllability is adjustable in a desired range of opening degree without changing the resolution of an actuator itself. The valve assembly (1) has a housing (2) inside which a path (810) is defined; a butterfly valve (3) having a valve body (31) placed in the path (810) and rockable and also having a valve shaft (30) rockable together with the valve body (31); an actuator (4) having a rockable output shaft (40); and a link mechanism section (5) having a drive-side lever (50) installed between an output shaft (40) and the valve shaft (30) and also having a driven-side lever (51) rockable about the valve shaft (30). The drive-side lever (50) is rockable within an actuator operation range (A2), and the driven-side lever (51) is rockable within a valve operation range (B2). The center line (A2c) of the actuator operation range (A2) and the center line (B2c) of the valve operation range (B2) are not in parallel with each other.

Description

Specification

Noku Norebu assembly

Technical field

The present invention relates to a valve assembly used in, for example, an exhaust gas recirculation system (hereinafter referred to as “EGR system”) and an exhaust brake system.

Background art

[0002] In an EGR system, an EGR passage is provided between an exhaust passage and an intake passage, and a part of the exhaust gas is recirculated to the intake side via the EGR passage. An EGR valve is arranged in the EGR passage to adjust the exhaust gas flow rate.

[0003] The opening degree of the EGR vanolev is feedback controlled! (See, for example, Patent Document 1).

That is, the ECU (Electric Control Unit) transmits the target opening calculated from the engine operating conditions (engine speed, accelerator opening, etc.) to the motor control unit. The motor control unit drives the motor that should achieve the opening target value. The actual amount of rotation of the motor drive shaft (that is, the actual opening) is detected by a sensor such as a Hall IC and transmitted to the motor control unit. The motor control unit compares the target opening value with the detected value, and adjusts the amount of current applied to the motor so that the deviation should be zero.

[0004] Specifically, a poppet valve or a butterfly valve is used as the EGR valve. Compared with poppet valves, the butterfly valve has a smaller flow resistance S and a larger passage area due to the difference in valve shape, allowing a large amount of exhaust gas to flow with the same pipe diameter. For example, Patent Document 2 introduces a butterfly valve that is driven via a link mechanism.

FIG. 13 (a) shows a top view of the valve assembly used in the EGR system, and FIG. 13 (b) shows a cross-sectional view of the EGR passage portion of the valve assembly. For convenience of explanation, the fully closed position is indicated by a solid line, and the fully open position is indicated by a dotted line.

[0006] As shown in FIG. 13, in the case of the valve assembly 9, the motor output shaft 90 and the butterfly The valve shaft 910 of the valve 91 is connected by a link mechanism 92. The drive-side lever 920 of the output shaft 90, that is, the link mechanism 92 can swing within the motor output shaft operating range A1 from the fully closed position Ala to the fully open position Alb. On the other hand, the driven lever 921 of the valve shaft 910, that is, the link mechanism 92 can swing within the valve operating range B1 from the fully closed position Bla to the fully open position Bib.

[0007] By the way, the butterfly valve is a force valve suitable for increasing the flow rate, and the flow controllability in the low opening range is important in conjunction with increasing the flow rate. Further, the valve body 911 of the butterfly valve 91 receives a load due to wind pressure from the exhaust gas flowing through the EGR passage 93. The load is transmitted to the motor via the link mechanism 92. In EGR systems, the ratio of the motor output shaft operating angle to the valve operating angle is usually constant from the fully closed position Bla to the fully open position Bib in order to keep the load characteristics of the motor as constant as possible. . The change amount (dY) of the valve operating angle with respect to the change amount (dX) of the motor output shaft operating angle is set such that dYa / dXa = dYb / dXb at any two points a and b. In other words, the valve assembly in FIG. 13 is set so that when the motor output shaft operating angle is changed by a predetermined amount (for example, 10 degrees), the valve operating angle is also changed by the same amount (10 degrees).

[0008] Specifically, the motor output shaft operating range A1 and the valve operating range B1 are both set over 90 degrees. Further, the center line Ale of the motor output shaft operating range A1 and the center line Blc of the knob operating range B1 are set to be parallel to each other.

[0009] Therefore, if it is assumed that an equivalent load fluctuation acts on the valve body 911 from the fully closed position to the fully open position (corresponding to the motor output shaft operating range Al and valve operating range B1), the load fluctuation The amount of deviation between the target opening value and the detected value is the same from the fully closed position to the fully open position.

Patent Document 1: Japanese Unexamined Patent Publication No. 2006-16975

Patent Document 2: Japanese Patent Application Laid-Open No. 62-146200

Disclosure of the invention

Problems to be solved by the invention

However, in practice, the load fluctuation acting on the valve body 911 is not equal from the fully closed position to the fully open position. Specifically, in a low opening range close to the fully closed position, the valve body 911 Fluctuation in load is increased. For this reason, according to the valve assembly 9 shown in FIG. 13, the amount of deviation in the low opening range increases. In other words, the valve assembly 9 has low controllability in the low opening range.

[0011] In addition, the feedback control of the EGR system is required to have high controllability particularly in the low opening range. In order to improve this problem specific to the butterfly valve 91, in order to improve the controllability in the low opening range, the minimum operation unit of the motor may be set small. In other words, the resolution of the motor itself may be increased. In this way, the motor can be precisely controlled in units of resolution. Whereas force S, in this case, the manufacturing cost of the valve assembly increases. Alternatively, the speed reduction ratio must be increased to sacrifice responsiveness. In the feedback control of the EGR system, high responsiveness is required.

The valve assembly of the present invention has been completed in view of the above problems. Therefore, an object of the present invention is to provide a valve assembly capable of adjusting the controllability within a desired opening range without changing the resolution of the actuator itself.

Means for solving the problem

(1) In order to solve the above-described problems, a valve assembly according to the present invention includes a housing in which a passage is defined, a valve body disposed in the passage and swingable, and swinging of the valve body. A butterfly valve that is disposed in the center and has a valve shaft that can swing together with the valve body, and an actuator that outputs a driving force for swinging the valve shaft and has a swingable output shaft. A drive-side lever interposed between the output shaft and the valve shaft and swingable about the output shaft; and a driven side lever swingable about the valve shaft A drive assembly, wherein the drive lever is swingable within an actuator operating range corresponding to the swing range of the output shaft, and the driven lever is Oscillating within a valve operating range corresponding to the oscillating range of the valve shaft. And the center line of the coater operating range, and the center line of the valve operating range, is characterized by not parallel to each other

Yes

According to the valve assembly of the present invention, the center line of the actuator operating range and the center line of the knob operating range are set so as not to be parallel to the force. Paraphrasing And the extension lines of both center lines are set to intersect each other. For this reason, in the desired opening range, the ratio of the actuator operating angle and the valve operating angle can be changed between the low opening range and the high opening range.

Thus, according to the valve assembly of the present invention, it is possible to adjust the resolution of the butterfly valve without changing the resolution of the actuator itself. That is, the controllability can be freely adjusted in the desired opening range.

[0016] (2) Preferably, the link mechanism section further includes a connecting rod for connecting the driving side lever and the driven side lever. In other words, in this configuration, the actuator and the butterfly valve are connected by a four-bar link in which a straight line connecting the valve shaft and the output shaft is a virtual fixed node. According to this configuration, it is possible to simplify the structure of the valve assembly. In addition, since the number of links is small, the transmission loss of driving force can be reduced.

(3) Preferably, in the configuration of (2), a plurality of the butterfly valves are provided in series, and the link mechanism section includes the same number of the driven side levers as a plurality of the butterfly valves and a plurality of the butterfly valves. And a driven connecting rod for connecting the driven levers to each other.

[0018] According to this configuration, a force S for driving a plurality of butterfly valves can be achieved by a single actuator. In addition, the ratio of the actuator operating angle of a single driving lever to the valve operating angles of a plurality of driven levers can be set to other than 1: 1. In addition, the ratio of the change in the valve operating angle of the plurality of driven side levers to the change in the actuator operating angle of the single drive side lever can be freely adjusted in a desired angle range.

Yes

(4) Preferably, in the configuration of (2) or (3) above, the angle between the center line of the actuator operating range and the center line of the valve operating range is such that the actuator unit It is preferable that the center line of the actuator operating range is set to 5% or more of the operating range and the valve closing direction is set in the valve closing direction with respect to the center line of the valve operating range. Here, the “fully closed position” refers to a position where the passage sectional area of the housing is minimized. In other words, if the cross-sectional area of the passage is the smallest, it is not necessary to close the passage completely! [0020] According to this configuration, dY / dX in a low opening range (for example, 0% position to 20% position with the fully closed position of the valve operating range as 0% position and the fully open position as 100% position). <1. For this reason, even if the actuator operating angle is changed by a predetermined amount, the valve operating angle does not change by the same amount, but changes by an amount smaller than the predetermined amount. Therefore, according to this configuration, it is possible to improve the controllability in the low opening range while ensuring the manufacturing cost of the valve assembly, the maximum flow rate of the fluid flowing in the passage, and the response of the butterfly valve. . In addition, the load S transmitted from the butterfly valve to the actuator via the link mechanism can be reduced.

[0021] In addition, according to this configuration, in a high opening range (for example, in the valve operation range, the fully closed position is 0% position and the fully open position is 100% position, 80% position to 100% position) dY / dX> l. For this reason, even if the actuator operating angle is changed by a predetermined amount, the valve operating angle does not change by the same amount but changes by an amount larger than the predetermined amount. Therefore, according to this configuration, the responsiveness of the valve to changes in the actuator can be improved in a high opening range.

[0022] Particularly preferably, the valve assembly having this configuration is preferably used in an EGR system. As mentioned above, EGR system feedback control requires both high controllability in the low opening range and high responsiveness from the fully open position to the fully closed position.

Yes

[0023] According to this configuration, at any point a in the low opening range and at any point b in the high opening range, dYa / dXa (low opening range) <dYb / dXb (high opening range) Therefore, high controllability can be secured in the low opening range while maintaining the response from the fully open position to the fully closed position.

The invention's effect

[0024] According to the valve assembly of the present invention, it is possible to provide a valve assembly capable of adjusting controllability in a desired opening range without changing the resolution of the actuator itself.

Brief Description of Drawings

FIG. 1 is a layout view of a valve assembly according to a first embodiment. FIG. 2 is a perspective view of the valve assembly.

FIG. 3 (a) is a top view of the valve assembly in a fully closed position. (b) is a sectional view of the EGR passage portion of the valve assembly.

FIG. 4 (a) is a top view of the valve assembly in a fully opened position. (b) is a sectional view of the EGR passage portion of the valve assembly.

5] is a top view of the link mechanism portion of the valve assembly.

6] A graph showing the correlation between the motor output shaft operating angle and the valve operating angle of the valve assembly.

FIG. 7 is a table showing a ratio of a motor output shaft operating angle to a valve operating angle at a valve operating angle of 10 degrees in the valve assembly.

8] A graph showing the correlation between the motor output shaft operating angle of the valve assembly and the exhaust gas flow rate.

9] (a) is a top view of the valve assembly of the second embodiment. (b) is a cross-sectional view of the EGR passage portion of the valve assembly.

FIG. 10] is a perspective view of the valve assembly of the third embodiment.

FIG. 11 (a) is a top view of the valve assembly. (b) is a sectional view of the EGR passage portion of the valve assembly.

12] A top view of the link mechanism of the valve assembly of the fourth embodiment.

FIG. 13 (a) is a top view of a conventional valve assembly. (b) is E of the valve assembly.

It is sectional drawing of a GR channel | path part.

Explanation of symbols

1: Vanolebu assembly, 2: Nosing, 20: Banolev housing part, 200: Through hole, 200a: Through hole, 201: First inner sleeve, 201a: First inner sleeve, 202: Second inner sleeve, 202a: second inner sleeve, 203: valve seat, 203a: valve seat, 21: motor housing, 3: butterfly valve, 3a: butterfly valve, 30: valve shaft, 30a: valve shaft, 31: valve body, 31a: Valve body, 4: Motor (actuator), 40: Output shaft, 5: Link mechanism, 50: Drive lever, 500: Nut, 51: Drive lever, 51a: Drive lever, 510: Nut, 510a: nut 卜, 52: connecting rod, 520: link pin, 521: link pin, 53: driven connecting rod, 5 30: Link pin, 531: Link pin, 8: EGR system, 80: Engine, 800: Combustion chamber, 801: Inlet mayuho redo, 801a: Intake passage, 802: Exo, 1st mayu honoredo, 802a: Exhaust passage, 81: EGR pipe, 810: EGR passage (passage), 810a: EGR passage (passage), 82: Motor control unit, 9: Valve assembly.

A2: Motor output shaft operation range (actuator operation range), A2a: Fully closed position, A2 b: Full open position, A2c: Center line, A3: Motor output shaft operation range (actuator operation range), A3a: All Closed position, A3b: Full open position, A3c: Center line, A4: Motor output shaft operating range (actuator operating range), A4a: Full closed position, A4b: Full open position, A4c: Center line, B2: Valve operating range, B2a: fully closed position, B2b: fully open position, B2c: center line, B3: valve operating range, B3a: fully closed position, B3b: fully open position, B3c: center line, B4: valve operating range, B 4a: fully closed position , B4b: Full open position, B4c: Center line, B5: Valve operating range, B5a: Full closed position, B5b: Full open position, B5c: Center line, L: Passage extending direction, Θ: Angle.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, an embodiment in which the valve assembly of the present invention is used in an EGR system will be described.

First, the arrangement of the valve assembly of this embodiment will be described. Figure 1 shows the layout of the valve assembly in this embodiment. As shown in FIG. 1, the EGR system 8 includes an engine 80, an EGR pipe 81, a motor control unit 82, and a valve assembly 1.

Yes

The engine 80 includes an inlet manifold hold 801 and an exhaust manifold hold 802. An intake passage 801a is defined inside the inlet manifold 801. An exhaust passage 802a is defined inside the exhaust manifold 802. The intake passage 801a and the air passage 802a are both in communication with the combustion chamber 800.

[0030] The EGR pipe 81 bypasses the exhaust passage 802a and the intake passage 801a, and connects the inlet manifold 801 and the exhaust manifold hold 802. An EGR passage 810 is defined in the EGR pipe 81. The EGR passage 810 is included in the passage of the present invention. The valve assembly 1 is interposed in the middle of the EGR pipe 81. And E Based on a command from CU (not shown), the motor control unit 82 controls the motor energization and adjusts the cross-sectional area of the EGR passage 810 from the fully closed position to the fully open position.

Next, the configuration of the valve assembly 1 of the present embodiment will be described. FIG. 2 shows a perspective view of the valve assembly 1 of the present embodiment. Fig. 3 (a) shows a top view of the valve assembly 1 and Fig. 3 (b) shows a cross-sectional view of the EGR passage part of the valve assembly. 2 and 3 show the valve assembly 1 in the fully closed position.

As shown in FIGS. 2 and 3, the valve assembly 1 includes a housing 2, a butterfly valve 3, a motor 4, and a link mechanism portion 5. Of these, the motor 4 is included in the actuator of the present invention.

The housing 2 is made of aluminum (iron or SUS is acceptable) and includes a valve housing portion 20 and a motor housing portion 21. Among these, the valve housing portion 20 is interposed in the middle of the EGR pipe 81 shown in FIG. The valve housing part 20 has a rectangular block shape. The valve housing part 20 is provided with a stepped cylindrical through hole 200. A first inner sleeve 201 and a second inner sleeve 202, both of which are made of SUS and are cylindrical, are fitted in the through-hole 200. The first inner sleeve 201 and the second inner sleeve 202 are arranged in series. The first inner sleeve 201 and the second inner sleeve 202 are arranged with a predetermined amount of deviation in the radial direction at the joint. Due to the deviation, the valve seat 203 is formed at the joint. The inner peripheral sides of the first inner sleeve 201 and the second inner sleeve 202 constitute part of the EGR passage 810.

[0034] The motor housing portion 21 has a C-shaped plate shape. A motor 4 is accommodated inside the C-shape of the motor housing portion 21. The output shaft 40 of the motor 4 protrudes outside the motor housing portion 21. The output shaft 40 and the drive shaft of the motor 4 are connected by a speed reduction mechanism (not shown) composed of a plurality of gears.

The butterfly valve 3 is disposed in the valve housing portion 20. Butterfly valve

3 includes a valve shaft 30 and a valve body 31. The valve body 31 is made of SUS and has a disk shape. The valve body 31 is disposed in the EGR passage 810. The valve stem 30 is made of SUS. It has a rod shape. The valve shaft 30 is fixed to the diameter portion of the valve body 31. One end of the valve shaft 30 protrudes outside the valve housing part 20. The valve shaft 30 and the valve body 31 can swing around the valve shaft 30. By the swinging, the valve element 31 can be separated from the valve seat 203. In the fully closed position, the valve body 31 is seated on the valve seat 203.

The link mechanism section 5 includes a drive side lever 50, a driven side lever 51, and a connecting rod 52.

The link mechanism section 5 has a folded scale shape (Z-shape) as a whole. The drive side lever 50, the drive side lever 51, and the connecting rod 52 are each made of aluminum (iron or SUS is acceptable) and have a thin plate shape.

[0037] One end of the drive side lever 50 is fixed to the output shaft 40 of the motor 4 by a nut 500. The drive side lever 50 and the output shaft 40 can swing around the output shaft 40. The other end of the driving lever 50 is pivotally connected to one end of the connecting rod 52 via a link pin 520. The other end of the connecting rod 52 is slidably connected to one end of the driven lever 51 via a link pin 521. The other end of the driven lever 51 is fixed to the protruding portion of the valve shaft 30 by a nut 510. The valve shaft 30 is always urged in the closing direction by a return spring (not shown) disposed in the valve housing portion 20.

[0038] Next, the movement of the valve assembly 1 of the present embodiment will be described. The opening of the butterfly valve 3 is feedback controlled. That is, the ECU (not shown) transmits the target opening value calculated from the operating conditions of the engine 80 (engine speed, accelerator opening, etc.) to the motor control unit 82. The motor control unit 82 drives the motor 4 that should achieve the target opening. The actual rotation amount (that is, the actual opening) of the output shaft 40 of the motor 4 is detected by a sensor such as a Hall IC and transmitted to the motor control unit 82. The motor control unit 82 compares the target opening value with the detected value and adjusts the energization amount of the motor 4 so that the deviation should be zero.

Hereinafter, as an example, a case of switching from the fully closed position to the fully opened position will be described. Figure

4 (a) shows a top view of the valve assembly 1 and FIG. 4 (b) shows a cross-sectional view of the EGR passage part of the valve assembly. FIG. 4 shows the valve assembly 1 in the fully opened position. The driving force of the motor 4 is transmitted to the valve body 31 of the butterfly valve 3 through the output shaft 40 → the driving side lever 50 → the connecting rod 52 → the driven side lever 51 → the valve shaft 30. When switching from the fully closed position to the fully open position, the output shaft 40 swings counterclockwise in FIG. For this reason, the drive side lever 50 also swings counterclockwise in FIG. Pushed by the driving lever 50, the connecting rod 52 shifts to the left in FIG. Pushed by the connecting rod 52, the driven lever 51 swings clockwise in FIG. For this reason, the valve shaft 30 and the valve body 31 also swing clockwise in FIG. By the swinging, the valve body 31 moves away from the valve seat 203 until it becomes substantially parallel to the passage extending direction of the EGR passage 810. In this manner, the fully closed position shown in FIG. 3 is switched to the fully opened position shown in FIG. In addition, when switching to the fully open position force fully closed position, each member is driven in the opposite direction to the above direction. Of course, it is also possible to switch to an intermediate position between the fully closed position and the fully open position.

FIG. 5 shows the trajectory of the link mechanism section from the fully closed position to the fully open position of the valve assembly 1 of the present embodiment. For convenience of explanation, the fully closed position is indicated by a solid line, and the fully open position is indicated by a dotted line.

As shown in FIG. 5, the output shaft 40, that is, the drive side lever 50 of the link mechanism section 5 can swing within the motor output shaft operating range A2 from the fully closed position A2a to the fully open position A2b. The motor output shaft operating range A2 is included in the actuator operating range of the present invention. The motor output shaft operating range A2 is set over 90 degrees. On the other hand, the valve shaft 30, that is, the driven lever 51 of the link mechanism 5 can swing within the valve operating range B2 from the fully closed position B2a to the fully open position B2b. The valve operating range B2 is set to 90 degrees, similar to the motor output shaft operating range A2. Here, the center line A2c of the motor output shaft operating range A2 and the center line B2c of the valve operating range B2 are set so as not to be parallel to each other. In other words, the extension line of the center line A2c and the extension line of the center line B2c are set to intersect each other. The angle Θ between the center line B2c of the valve operating range B2 and the center line A2c of the motor output shaft operating range A2 is 15 degrees (16.7% = 15 degrees / 90 degrees (motor output shaft operating range A2 ) X 100) And motor output shaft Operating range Α2 center line A2c is the valve operating range Β2 center line B2c clockwise Direction (that is, the valve closing direction).

[0043] Next, the function and effect of the valve assembly 1 of the present embodiment will be described. FIG. 6 shows the correlation between the motor output shaft operating angle and the valve operating angle of the valve assembly 1 of the present embodiment. Figure 7 shows the ratio of the motor output shaft operating angle to the valve operating angle when the valve operating angle of the valve assembly 1 is 10 degrees. Figure 8 shows the correlation between the motor output shaft operating angle of the valve assembly 1 and the exhaust gas flow rate. In FIGS. 6, 7, and 8, the 0 degree position (Odeg.) Corresponds to the fully closed position, and the 90 degree position (90 degrees) corresponds to the fully open position.

In FIG. 6, FIG. 7, and FIG. 8, the data of Θ = 0 deg. Is data of the conventional valve assembly (see FIG. 13 above). The data of Θ = 15 deg. Is the data of the valve assembly 1 of the present embodiment described above. In FIGS. 6 and 7, the data of Θ = 25 deg. And Θ = 35 deg. Are data when the included angle Θ is further increased in the valve assembly 1 of the present embodiment.

[0045] As shown in Fig. 6, in the conventional valve assembly, dYa / dXa (low opening range) = dYb / at any point a in the low opening range and at any point b in the high opening range. Since it is dXb (high opening range), the valve operating angle when the motor output shaft operating angle is changed by a predetermined amount is the same from the fully closed position to the fully open position. In contrast, according to the valve assembly 1 of the present embodiment, in the low opening range (50% or less of the valve operating range), the change in the valve operating angle (dXa) with respect to the change in the motor output shaft operating angle (dXa) The ratio of dYa) is smaller than in the high opening range (over 50%). For this reason, even if the motor output shaft operating angle is changed by a predetermined amount, the valve operating angle changes by an amount smaller than the high opening range. Therefore, according to the valve assembly 1 of the present embodiment, it is possible to improve the controllability in the low opening range without increasing the resolution of the motor 4 itself.

Specifically, as shown in FIG. 7, the ratio of the motor output shaft operating angle to the valve operating angle at a valve operating angle of 15 deg. Is 1: 0.665. For this reason, the amount of deviation between the target opening value and the detected value can be reduced by 35% compared to the conventional valve assembly. Incidentally, as shown in FIG. 7, if the included angle Θ force 25 deg. (Or 45 ^_0/0, if the included angle Θ force 35 deg. 57%, it is possible to respectively reduce the amount of deviation. [0047] Further, as shown in FIG. 8, in the low opening range, the ratio of the change in the exhaust gas flow rate with respect to the change in the motor output shaft operating angle is smaller than that of the conventional valve assembly. For this reason, flow control with extremely high accuracy can be executed.

[0048] In addition, according to the valve assembly 1 of the present embodiment, as shown in Fig. 6 above, in the high opening range (over 50%), the valve operation against the change (dXb) of the motor output shaft operating angle. Angular change (dYb) ratio force Increased compared to the low opening range (50% or less). For this reason, even if the motor output shaft operating angle is changed by a predetermined amount, the valve operating angle changes by an amount larger than the low opening range. Therefore, according to the valve assembly 1 of the present embodiment, the responsiveness of the butterfly valve 3 to changes in the motor output shaft operating angle can be improved in a high opening range.

Specifically, as shown in FIG. 8, in the high opening range, the ratio of the change in the exhaust gas flow rate with respect to the change in the motor output shaft operating angle is larger than that in the conventional valve assembly. . For this reason, while maintaining the response from the fully open position to the fully closed position, it is possible to ensure high control and controllability in the low opening range.

[0050] Further, according to the valve assembly 1 of the present embodiment, the link mechanism section includes the valve shaft 30 and the output shaft.

It consists of a four-bar link with a straight line connecting 40 as a virtual fixed node (see Figure 5 above). For this reason, the structure of the valve assembly 1 can be simplified. In addition, since the number of links is small, the transmission loss of driving force can be reduced.

[0051] By the way, when the recirculation amount of the desired exhaust gas (the amount passing through the EGR passage 810) is large, the passage diameter of the EGR passage 810 is relatively large. For this reason, the valve element 31 that controls the opening and closing of the EGR passage 810 inevitably increases in diameter. Normally, when the diameter of the valve body 31 is increased, the flow rate of the exhaust gas in the low opening range is also increased. For this reason, controllability is reduced.

In this regard, according to the valve assembly 1 of the present embodiment, even when the EGR passage 810, that is, the valve body 31 is increased in diameter, the possibility that the controllability in the low opening range is lowered is small. Thus, the valve assembly 1 of the present embodiment is suitable for opening / closing control of the EGR passage 810 having a relatively large flow rate.

[0053] Further, according to the valve assembly 1 of the present embodiment, the output shaft 40 and the valve shaft 30 are linked to each other. They are connected by part 5. Therefore, the structure is simple compared to the case where the driving force is transmitted by a mechanism using a belt or chain. In addition, as compared with the case where the driving force is transmitted by a mechanism using sliding between the guide portion and the guided portion, it is possible to prevent the deterioration of controllability due to wear. The structure is also simple.

Further, according to the valve assembly 1 of the present embodiment, the return spring is interposed between the valve shaft 30 and the driven lever 51. For this reason, the force S that suppresses the rattling of the link mechanism section 5 can be achieved. When the rattling is suppressed, the contact portions of the members constituting the link mechanism portion 5 are always constant. For this reason, the connection distance by the link mechanism part 5 is also constant, and the opening degree is stabilized. Therefore, the controllability of the butterfly valve 3 can be improved.

The difference between the valve assembly of this embodiment and the valve assembly of the first embodiment is set so that the center lines of both are not parallel by adjusting the valve operation range that is not the motor output shaft operation range. It is a point. Therefore, only the differences will be described here.

FIG. 9A shows a top view of the valve assembly of the present embodiment, and FIG. 9B shows a cross-sectional view of the EGR passage portion of the valve assembly. For convenience of explanation, the fully closed position is indicated by a solid line, and the fully open position is indicated by a dotted line. In addition, parts corresponding to those in FIG.

As shown in FIG. 9, the center line A3c of the motor output shaft operating range A3 is set parallel to the passage extending direction L of the EGR passage 810. The motor output shaft operating range A3 is included in the actuator operating range of the present invention. In the fully closed position A3a, the center line A3c force is also set at 45 degrees clockwise. The fully open position A3b is set at 45 degrees counterclockwise from the center line A3c!

[0058] On the other hand, the center line B3c of the valve operating range B3 is set not to be parallel to the passage extending direction L of the EGR passage 810 (that is, the center line A3c of the motor output shaft operating range A3). ing. Specifically, the extension line of the center line B3c and the extension line of the center line A3c are set to intersect at an angle of 15 degrees. The fully closed position B3a is set at 45 degrees counterclockwise from the center line B3c. Fully open position B3b is clockwise from center line B3c. The direction is set to 45 °!

[0059] The valve assembly 1 according to the present embodiment has the same operational effects as the valve assembly according to the first embodiment in a portion having a common configuration. Further, as with the valve assembly 1 of the present embodiment, the valve operating range B3 that is not the motor output shaft operating range A3 is changed from the conventional valve assembly (see FIG. 13). Controllability at a desired opening can be adjusted.

[0060] <Third embodiment>

The difference between the valve assembly of this embodiment and the valve assembly of the first embodiment is that two butterfly valves are connected in series. Therefore, only the differences will be described here.

FIG. 10 shows a perspective view of the valve assembly of the present embodiment. The parts corresponding to those in Fig. 2 are denoted by the same reference numerals. Fig. 11 (a) shows a top view of the valve assembly 1 and Fig. 11 (b) shows a cross-sectional view of the EGR passage part of the valve assembly. For convenience of explanation, the fully closed position is indicated by a solid line, and the fully open position is indicated by a dotted line. The parts corresponding to those in Fig. 3 are denoted by the same reference numerals.

[0062] As shown in FIGS. 10 and 11, the EGR system includes two EGR passages 810 and 810a. The EGR passages 810 and 810a are included in the passage of the present invention. The valve housing 20 of the housing 2 is provided with a through hole 200a having the same shape as the through hole 200. A first inner sleeve 201a and a second inner sleeve 202a having the same shape as the first inner sleeve 201 and the second inner sleeve 202 are fitted in the through hole 200a. A valve seat 203a is formed at the joint between the first inner sleeve 201a and the second inner sleeve 202a. The inner peripheral sides of the first inner sleeve 201a and the second inner sleeve 202a constitute a part of the EGR passage 810a.

The butterfly valve 3 a has the same shape as the butterfly valve 3 and is connected to the side of the butterfly valve 3. The valve body 31a is disposed in the EGR passage 810a. One end of the valve shaft 30a protrudes outside the valve housing portion 20. The valve shaft 30a and the valve body 31a can swing around the valve shaft 30a. By the swinging, the valve body 31a can be separated from the valve seat 203a. The link mechanism unit 5 includes a drive side lever 50, two driven side levers 51 and 51a, a connecting rod 52, and a driven side connecting rod 53. The drive side lever 50, the driven side levers 51 and 51a, the connecting rod 52, and the driven side connecting rod 53 are each made of aluminum (iron and other materials are also possible) and have a thin plate shape.

[0065] One end of the connecting rod 52 is swingably connected to the drive side lever 50 via a link pin 520. The other end of the connecting rod 52 is swingably connected to one end of the driven lever 51 via a link pin 530. In addition, the other end of the connecting rod 52 is swingably connected to one end of the driven connecting rod 53 via a link pin 530. The other end of the driven side connecting rod 53 is swingably connected to one end of the driven side lever 51a via a link pin 531. The other end of the driven lever 51a is fixed to the protruding portion of the valve shaft 30a by a nut 510a. Here, the total length of the two driven levers 51, 51a is set equal. In addition, the total length of the straight line connecting the valve shaft 30 and the valve shaft 30a is set equal to the total length of the driven connecting rod 53. That is, the two butterfly valves 3, 3a are connected by a parallel link having a straight line connecting the valve shaft 30 and the valve shaft 30a as a virtual fixed node. The valve shaft 30a is always urged in the closing direction by a return spring (not shown) disposed in the valve housing portion 20.

[0066] A center line B4c of the valve operating range B4 is set parallel to the passage extending direction of the EGR passage 810. The fully closed position B4a is set at a position 45 degrees counterclockwise from the center line B4c. The fully open position B4b is set at 45 degrees clockwise from the center line B4c.

[0067] Similarly, the center line B5c of the valve operating range B5 is set parallel to the passage extending direction of the EGR passage 810a. The two EGR passages 810 and 810a are parallel to each other. The fully closed position B5a is set at a position 45 degrees counterclockwise from the center line B5c. Fully open position B5b is set at 45 degrees clockwise from center line B5c

Yes

[0068] On the other hand, the center line A4c of the motor output shaft operating range A4 is set not to be parallel to the two center lines B4c and B5c. The motor output shaft operating range A4 is included in the actuator operating range of the present invention. Fully closed position A4a is center line It is set at 45 degrees clockwise from A4c. The fully open position A4b is set at a position 45 degrees counterclockwise from the center line A4 c.

[0069] The valve assembly 1 according to the present embodiment has the same operational effects as the valve assembly according to the first embodiment in a portion having a common configuration. Further, according to the valve assembly 1 of the present embodiment, the two butterfly valves 3 and 3a can be driven synchronously by the single motor 4. Further, the ratio between the single motor output shaft operating angle and the two valve operating angles can be set by changing the low opening range and the high opening range as in the first embodiment.

[0070] Further, according to the valve assembly 1 of the present embodiment, the return spring is interposed between the valve shaft 30a and the driven lever 51a. For this reason, the force S improves the controllability of the butterfly valve 3a.

The difference between the valve assembly of this embodiment and the valve assembly of the first embodiment is that the link mechanism is configured in a U-shape. Therefore, only the differences will be explained here.

FIG. 12 shows a top view of the link mechanism portion of the valve assembly of the present embodiment. Parts corresponding to those in FIG. 5 are denoted by the same reference numerals. For convenience of explanation, the valve body 31 of the butterfly valve 3 is hatched.

[0073] As shown in FIG. 12, the drive side lever 50, the connecting rod 52, and the driven lever 51 are not Z-shaped (see FIG. 5 above) but are U-shaped. When the butterfly valve 3 is switched to the fully closed position (solid line) force in the fully open position (dotted line) direction, the valve element 31 swings counterclockwise. On the other hand, when switching the butterfly valve 3 from the fully open position to the fully closed position, the valve body 31 swings in the clockwise direction. The valve assembly 1 of the present embodiment has the same operational effects as the valve assembly of the first embodiment.

[0074] <Others>

The embodiment of the valve assembly of the present invention has been described above. However, the embodiment is not particularly limited to the above embodiment. It is also possible to carry out various modifications and improvements that can be made by those skilled in the art. [0075] For example, in the above embodiment, the motor output shaft operation ranges A2, A3, A4 and the valve operation ranges B2, B3, B4, B5 are set to 90 degrees, respectively. However, these operating ranges may be set to other than 90 degrees. Also, the motor output shaft operating range is different from the valve operating range! /!

Further, the length, shape, and number of the drive side lever 50, the driven side levers 51 and 51a, the connecting rod 52, and the driven side connecting rod 53 of the link mechanism 5 are not particularly limited. The link mechanism 5 may be a link system other than a four-bar link.

In the above embodiment, return springs are arranged between the valve shaft 30 and the driven lever 51 and between the valve shaft 30a and the driven lever 51a. However, a return spring may be arranged between the output shaft 40 and the drive side lever 50. In this case, it is possible to improve controllability. Further, return springs may be arranged on both the driving side and the driven side. Also, the urging direction by the return spring may be either the opening direction or the closing direction. Moreover, it is not necessary to arrange a return spring.

In the above embodiment, the speed reduction mechanism is interposed between the drive shaft of the motor 4 main body and the output shaft 40. However, the speed reduction mechanism may not be interposed. That is, the drive shaft itself may be the output shaft 40.

[0079] The number of butterfly valves 3 and 3a is not particularly limited! /. When there are many arrangements! /, For example, a plurality of driven levers are arranged at predetermined intervals of the long driven connecting rod 53, and a plurality of corresponding driven levers are arranged in a 1: 1 relationship. A butterfly valve may be arranged.

[0080] In the above embodiment, the low opening range is set to 50% or less of the valve operating range, but the width of the low opening range is not particularly limited. It may be set appropriately according to the request of the system using the knob assembly 1. For example, it may be 10% or less, 40% or less, or 60% or less.

Similarly, the width of the high opening range is not particularly limited. It can be set as appropriate according to the requirements of the system using the nano-rev assembly 1. For example, it may be 90% or more, 60% or more, or 40% or more of the valve operating range.

[0082] In the above embodiment, the valve assembly 1 of the present invention is used in the EGR system 8. However, for example, an exhaust brake system, an exhaust purification system, an intake system (slot) Can also be used for Nole Valve)! / ヽ.

Even if there is no need to improve controllability in the low opening range as in the EGR system 8, if the valve assembly 1 of the present invention is used in any system that requires a butterfly valve, the flow rate in the low opening range is used. Controllability can be improved.

Claims

The scope of the claims

[1] a housing with a passage defined therein;

A butterfly valve having a valve body disposed in the passage and swingable; and a valve shaft disposed in a swing center of the valve body and swingable together with the valve body;

An actuator that outputs a driving force for swinging the valve shaft and has a swingable output shaft;

A link mechanism having a drive side lever interposed between the output shaft and the valve shaft and swingable about the output shaft, and a driven side lever swingable about the valve shaft When,

A valve assembly comprising:

The drive side lever can swing within an actuator operating range corresponding to the swing range of the output shaft,

The driven lever can swing within a valve operating range corresponding to the swing range of the valve shaft,

The valve assembly characterized in that the center line of the actuator operating range and the center line of the valve operating range are not parallel to each other.

[2] The valve assembly according to [1], wherein the link mechanism portion further includes a connecting rod for connecting the driving side lever and the driven side lever.

[3] A plurality of the butterfly valves are connected in series.

3. The banlev assembly according to claim 2, wherein the link mechanism section includes the same number of the driven levers as the plurality of butterfly valves, and a driven connecting rod that connects the plurality of driven levers.

[4] The angle between the center line of the actuator operating range and the center line of the valve operating range is 5% or more of the actuator operating range, and the center line of the actuator operating range is the center line of the actuator operating range. 4. A valve assembly according to claim 2 or claim 3, wherein the valve operating range is set in the valve closing direction relative to the center line of the valve operating range.