JP2009191707A - Exhaust valve device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exhaust valve device which can be made small and compact while eliminating a thermal influence through the sufficient heat radiation of exhaust heat. <P>SOLUTION: An exhaust valve device 1 comprises an exhaust valve 2 which pivotally supports a valve shaft 7 in a valve body 3 including an exhaust passage 6 therein and which keeps a valve element 8 for opening/closing an exhaust passage 6 in a valve shaft 7, a drive case 4 for accommodating an electric motor 12 serving as a drive source and gears 13, 15, 16, 17 for transmitting the rotation of the electric motor 12 to the valve shaft 7, an opening detection sensor 5 for detecting an opening of the exhaust valve 2, and a cooling water passage 19 arranged on a peripheral edge of the drive case 4. A heat insulator 11 is sandwiched between the valve body 3 and drive case 4 to be fastened therebetween. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an exhaust valve device including, for example, an exhaust valve that opens and closes an exhaust passage of a vehicle engine and an electric motor that opens and closes the exhaust valve.

  An exhaust pipe of a vehicle such as a motorcycle or an automobile is provided with an exhaust valve device that includes a butterfly-type exhaust valve that functions as an exhaust brake valve and a warm-up valve and an actuator that drives the butterfly-type exhaust valve.

  In recent years, some cylinders of a multi-cylinder engine have been deactivated during steady running for the purpose of improving the fuel efficiency of a vehicle equipped with a multi-cylinder engine. Is known to occur. It is also known that this abnormal noise can be reduced by opening and closing the exhaust pipe and controlling the exhaust gas flow rate according to the operating state of the engine. For this purpose, an exhaust valve device is provided in the exhaust system of the engine. It has been.

  By the way, Patent Document 1 discloses an exhaust valve device that opens and closes an exhaust passage by fixing a valve body to a rotary shaft rotatably supported in a valve housing and rotating the rotary shaft by an actuator. Is constituted by an electric motor with a speed reducer that rotates the rotating shaft, a position sensor that detects a rotational position of the rotating shaft, and a controller that controls the drive of the electric motor with the speed reducer. An exhaust valve device has been proposed in which the (valve opening) is controlled steplessly.

In Patent Document 2, in a motor-driven throttle valve device, a cooling water pipe is attached to a metal plate attached to a housing that houses the motor, and the engine cooling water is allowed to flow through the cooling water pipe to cool the motor. A configuration is disclosed.
JP 2001-289071 A WO2005 / 052347

  However, in the exhaust valve device described in Patent Document 1, since a worm gear or hypoid gear is used for the speed reducer, when the power supply source to the motor fails, the valve body is fixed at the position immediately before the failure, Depending on the position of the valve body (valve opening), there is a problem that the vehicle travels. Further, since a heat insulating material and an air layer are used as means for avoiding the influence of exhaust heat, there is a problem that it is difficult to make the apparatus compact.

  Further, in the exhaust valve device described in Patent Document 1, aluminum with good heat dissipation is provided between the fin coupling that connects the output shaft from the reduction gear on the actuator side and the rotary shaft of the valve, and between the valve housing and the electric motor. By interposing a heat shield plate (insulator) made of a system material, high heat from the exhaust passage is blocked. In this configuration, although it is possible to block high heat from the exhaust passage, it is difficult to avoid the influence of heat in a high temperature atmosphere.

  The device proposed in Patent Document 2 is an EGR control device that recirculates a part of the exhaust gas, and is configured to guide the exhaust gas into the intake passage through the exhaust gas passage. A cooling device is provided in the exhaust gas passage, By performing the replacement, the exhaust gas heat is lowered and the exhaust gas is sent to the EGR valve. A circuit board for driving and controlling the throttle valve is built in the cover part through a metal plate to dissipate heat. In a high temperature atmosphere, the metal plate penetrates the resin cover and is exposed to the outside. Thus, the heat dissipation effect of the circuit board is enhanced. Furthermore, a cooling water pipe is provided on the metal plate, and the cooling effect is enhanced by the cooling water.

  When the cooling device having the above configuration is separately provided in the exhaust gas passage, the exhaust valve device having the above configuration causes a problem in that the size of the exhaust valve device is increased, and a space for the cooling device must be secured on the equipment. It is difficult to apply. In addition, the configuration in which the cooling water pipe is provided on the metal plate has low heat radiation efficiency, and it is necessary to block heat from the atmosphere in a high-temperature atmosphere in a control device such as a motor in order to apply it to the exhaust system.

  The present invention has been made in view of the above-described problems, and the object of the present invention is an electric motor that is a drive source of a valve body mounted on the exhaust valve device, an opening degree detecting means that detects the opening degree of the valve, and the like. In order to ensure the operational stability of a control device that controls an exhaust valve device, it is intended to provide an exhaust valve device that can radiate exhaust heat sufficiently to eliminate thermal influences and can be reduced in size and size. .

In order to achieve the above object, according to the first aspect of the present invention, a valve body is rotatably supported on a valve body in which an exhaust passage is formed, and a valve body for opening and closing the exhaust passage is attached to the valve shaft. An exhaust valve comprising:
A drive case containing an electric motor as a drive source and a gear for transmitting the rotation of the electric motor to the valve shaft;
An opening degree detecting means for detecting an opening degree of the exhaust valve;
In the exhaust valve device with
A cooling water passage is provided in a peripheral portion of the drive case.

  According to a second aspect of the present invention, in the first aspect of the present invention, the cooling water passage is formed on two opposing surfaces of the drive case, and the two cooling water passages communicate with each other.

  A third aspect of the invention is characterized in that in the first or second aspect of the invention, a heat insulating material is sandwiched between the valve body and the drive case.

  According to a fourth aspect of the present invention, there is provided the urging means according to any one of the first to third aspects, wherein the urging means for urging the exhaust valve in a normally opening direction is provided.

  According to the first aspect of the present invention, since the drive case is forcibly cooled by the cooling water flowing through the cooling water passage formed in the driving case, the heat (exhaust gas) of the hot exhaust gas flowing through the exhaust passage of the valve body. (Heat) can be sufficiently absorbed by the cooling water to eliminate the adverse thermal effects on the electric motor and the opening detection means, and the operational stability of these can be improved. Further, since the drive case is directly cooled by the cooling water without using an air layer or the like as means for avoiding the influence of the exhaust heat, the exhaust valve device can be configured to be small and compact. Furthermore, by providing a cooling water passage in the peripheral portion of the drive case, the electric motor and the opening degree detection means can be insulated from the heat in the atmosphere.

  According to the second aspect of the present invention, the cooling water passages are formed on the two opposing surfaces of the drive case, and the two cooling water passages are communicated with each other. It is simultaneously cooled from the two surfaces by the cooling water flowing through both cooling water passages. For this reason, the cooling efficiency of the drive case is doubled, and the thermal adverse effect on the electric motor housed in the drive case and the opening degree detection means attached to the drive case is more effectively eliminated, and these operational stability Can be further increased.

  According to the invention described in claim 3, since the valve body and the drive case are fastened via the heat insulating material, heat transfer from the high-temperature exhaust gas flowing through the exhaust passage of the valve body to the drive case is effectively performed by the heat insulating material. It is shut off, and the adverse thermal effects on the electric motor and the opening degree detecting means are eliminated, and their operational stability is enhanced.

  According to the invention described in claim 4, since the exhaust valve is always urged in the opening direction by the urging means, the exhaust valve is provided even when an abnormality occurs in the electric motor or the opening degree detecting means. Opening prevents the occurrence of the problem that the exhaust passage is closed and the flow of exhaust gas chokes, and high fail-safety is ensured. Further, since the backlash of the exhaust valve is absorbed by the urging means, the responsiveness of the exhaust valve is improved.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a block diagram showing a system configuration of an exhaust system of a vehicle engine equipped with an exhaust valve device according to the present invention.

  The vehicle engine 50 according to the present embodiment is a multi-cylinder engine, and an intake manifold 51 is connected to the intake side, and an exhaust manifold 52 is connected to the exhaust side. Although not shown, an air cleaner is connected to the intake manifold 51 via a throttle body and a surge tank.

  A catalytic converter 53, an exhaust valve device 1 according to the present invention, and a muffler 54 are sequentially connected to an exhaust pipe extending from the exhaust manifold 52.

  By the way, the exhaust valve device 1 according to the present invention is controlled by a control device (ECU) 60, and the control device 60 has an engine speed detected by an engine speed sensor 61 and a water temperature sensor 62. The detected coolant temperature, the accelerator opening (throttle opening) detected by the accelerator opening sensor 63, and the engine load detected by the load sensor 64 are input. Based on these inputs, the controller 60 controls the exhaust valve device 1. Is controlled.

  Thus, when intake air (fresh air) is supplied from the intake manifold 51 to each cylinder of the engine 50, fuel is injected into the intake air to form an air-fuel mixture, which is combusted in the combustion chamber of each cylinder. To be served. The high-temperature exhaust gas generated by the combustion of the air-fuel mixture is discharged from the engine 50 to the exhaust manifold 52 and purified in the process of flowing from the exhaust manifold 52 through the catalytic converter 53. Thereafter, after the flow rate and pressure are adjusted by the exhaust valve device 1 whose drive is controlled by the control device 60 as described above, the exhaust gas is silenced by passing through the muffler 54 and finally exhausted to the atmosphere. .

  Next, details of the exhaust valve device 1 according to the present invention will be described with reference to FIGS.

  2 is a rear view of the exhaust valve device according to the present invention, FIG. 3 is a right side view of the exhaust valve device (a view in the direction of arrow A in FIG. 1), FIG. 4 is a perspective view of the exhaust valve device, and FIG. FIG. 6 is a perspective view showing the exhaust valve device with the water passage cover removed from the front, FIG. 6 is a rear view showing the configuration inside the drive case of the exhaust valve device, and FIG. 7 is an exploded perspective view of the exhaust valve device.

  As shown in FIG. 2, the exhaust valve device 1 according to the present invention fastens a drive case 4 to a valve body 3 of the exhaust valve 2 and detects the opening degree of the exhaust valve 2. The sensor 5 is configured to be fastened to the end surface (left end surface) of the drive case 5.

  The exhaust valve 2 is a disc-shaped valve body 8 that opens and closes the exhaust passage 6 on a valve shaft 7 that is pivotally supported through an exhaust passage 6 having a circular cross section formed in the valve body 3. Are attached by two screws 9. As shown in FIGS. 2 and 3, the exhaust valve 2 has an end face (right end face) of the drive case 4 at the four corners of a rectangular flange portion 3 a formed integrally with the end portion of the valve body 3 by bolts 10. The heat insulating material 11 is interposed between the valve body 3 and the drive case 4. That is, the valve body 3 and the drive case 4 are fastened to each other with the heat insulating material 11 interposed therebetween.

  The axial end of the valve shaft 7 is rotatably supported by a bearing (not shown), and one end (the right end in FIG. 2) passes through the drive case 4 and faces the inside. (See FIG. 6).

  The drive case 4 incorporates a drive system for opening and closing the exhaust passage 6 by turning the valve shaft 7 of the exhaust valve 2 and the valve body 8 attached thereto. That is, as shown in FIG. 6, an electric motor 12 as a drive source is accommodated in the drive case 4, and the end of the output shaft 12a of the electric motor 12 has a small diameter as shown in FIG. A pinion 13 is bound. An intermediate shaft 14 is arranged in the drive case 4 in parallel with the output shaft 12 a of the electric motor 12, and a large-diameter gear 15 and a small-diameter gear 16 are bound to the intermediate shaft 14. The large-diameter gear 15 meshes with the pinion 13 attached to the output shaft 12 a of the electric motor 12.

  Further, as described above, the valve shaft 7 of the exhaust valve 2 passes through the drive case 4 and faces the inside thereof. As shown in FIGS. 6 and 7, a sector gear 17 is attached to the end of the valve shaft 7. The sector gear 17 meshes with the small-diameter gear 16 connected to the intermediate shaft 14. Here, a return spring 18 as a biasing means is wound around the outer periphery of the boss portion 17 a of the sector gear 17. One end of the return spring 18 is engaged with the sector gear 17, and the other end is engaged with the drive case 4. The valve shaft 7 and the valve body 8 (exhaust valve 2) attached thereto are always urged in the opening direction by the return spring 18.

  Further, as shown in FIGS. 4 and 5, a cooling water passage 19 is provided on the back surface (front surface in FIG. 4) and the front surface (front surface in FIG. 5), which are two opposing surfaces of the drive case 4. , 20 are formed, and the cooling water passages 19, 20 communicate with each other through an elliptical communication hole 21 formed in the drive case 4. As shown in FIGS. 2 to 4, rectangular plate-shaped water passage covers 22 and 23 are attached to the back and front of the drive case 4 with a plurality of (eight in the illustrated example) screws 24. The cooling water passages 19 and 20 formed on both surfaces of the drive case 4 are respectively covered with water passage covers 22 and 23, and water passages are formed therein.

  Furthermore, two nipples 25 and 26 bent in an L-shape are attached to the end face (lower end face in the figure) of the drive case 4, and one nipple 25 is a cooling formed on the back side of the drive case 4. The other nipple 26 opens to the water passage 19, and the other nipple 26 opens to the cooling water passage 20 formed on the front side of the drive case 4. Although not shown, one nipple 25 is supplied with cooling water from the engine 50 shown in FIG. 1 and is returned to the engine 50 from the other nipple 26.

  The opening degree detection sensor 5 is attached to the end face (left end face) opposite to the side on which the valve body 3 of the drive case 4 is attached by four screws 27. The input shaft of the detection sensor 5 is connected to the valve shaft 7 of the exhaust valve 2. The opening degree detection sensor 5 is a magnetic sensor, and outputs a change in magnetic flux density and magnetic resistance due to the rotation of the valve shaft 7 as a change in output voltage. The output signal is output to the control device 60 shown in FIG. To be sent. As the opening degree detection sensor 5, a contact sensor or the like can be used in addition to the magnetic sensor.

  Thus, in the exhaust valve device 1 configured as described above, when the electric motor 12 is driven by the control device 60 shown in FIG. 1, the rotation of the output shaft 12a is the pinion 13, the large diameter gear 15, the small diameter. It is decelerated through the gear 16 and the sector gear 17 and transmitted to the valve shaft 7, and the valve shaft 7 and the valve body 8 attached thereto rotate in the same direction by the same angle. As described above, when the valve body 8 rotates in the valve body 3, the flow rate and pressure of the exhaust gas flowing through the exhaust passage 6 in the valve body 3 are adjusted. The opening degree of the exhaust valve 2 is detected by the opening degree detection sensor 5, and the detection signal is fed back to the control device 60 shown in FIG. Then, the control device 60 obtains the opening degree of the exhaust valve 2 from the detection signal input from the opening degree detection signal, and feedback-controls the electric motor 12 so that the opening degree becomes equal to the set value.

  Further, the cooling water of the engine 50 shown in FIG. 1 is supplied to the exhaust valve device 1, and this cooling water flows from one nipple 25 into the cooling water passage 19 formed on the back side of the drive case 4, The drive case 4 is cooled in the process of flowing through the cooling water passage 19. Then, the cooling water that has cooled the drive case 4 flows into the other (front side) cooling water passage 20 from the communication passage 21, and after cooling the driving case 4 in the course of flowing through the cooling water passage 20, After being discharged from the nipple 26 to the outside of the drive case 4 and returned to the engine 50 and cooled by heat exchange with a radiator (not shown), the engine 50 and the exhaust valve device 1 are continuously circulated to cool them. Provided.

  As described above, in the present embodiment, the driving case 4 is forcibly cooled by the cooling water flowing through the cooling water passages 19 and 20 formed in the driving case 4, so that the high temperature flowing through the exhaust passage 6 of the valve body 3. The exhaust gas heat (exhaust heat) can be sufficiently absorbed by the cooling water to eliminate the adverse thermal effects on the electric motor 12 and the opening degree detection sensor 5, and the operational stability of these can be improved. Since the drive case 4 is directly cooled by the cooling water without using an air layer or the like as means for avoiding the influence of the exhaust heat, the exhaust valve device 1 can be configured to be small and compact.

  Further, in the present embodiment, the cooling water passages 19 and 20 are formed on the two opposing surfaces of the drive case, respectively, and both the cooling water passages 19 and 20 are communicated with each other through the communication holes 21. The area is enlarged, and the drive case 4 is simultaneously cooled from the two surface sides by the cooling water flowing through both the cooling water passages 19 and 20. For this reason, the cooling efficiency of the drive case 4 is doubled, and the adverse thermal effects on the electric motor 12 housed in the drive case 4 and the opening degree detection sensor 5 attached to the drive case 4 are more effectively eliminated. These operational stability can be further improved.

  Furthermore, in this embodiment, since the valve body 3 and the drive case 4 are fastened via the heat insulating material 11, heat transfer from the high-temperature exhaust gas flowing through the exhaust passage 6 of the valve body 3 to the drive case 4 is the heat insulating material. 11 is effectively cut off, and the adverse thermal effects on the electric motor 12 and the opening degree detection sensor 5 are eliminated, and the operational stability thereof is enhanced. In this way, the transmission of the exhaust heat to the drive case 4 is blocked by the heat insulating material 11, and the drive case 4 is forcibly cooled by the engine cooling water, so the opening degree detection sensor attached to the drive case 4 The cover 5 can be made of resin, and the cost of the exhaust valve device 1 can be reduced.

  In the present embodiment, the exhaust valve 2 is always urged in the opening direction by the return spring 18, so that even if an abnormality occurs in the electric motor 12, the opening detection sensor 5, etc. Since the valve 2 is open, the exhaust passage 6 is closed and the flow of the exhaust gas is choked, so that a high fail-safe property is ensured. Since the backlash of the exhaust valve 2 is absorbed by the urging means, the responsiveness of the exhaust valve 2 is improved.

  In addition, in the present embodiment, since the electric motor 12 is used as a drive source for opening and closing the exhaust valve 2, the exhaust valve 2 can be controlled to open and close with good responsiveness, and the exhaust valve can be controlled even when the engine 50 is stopped. 2 can be opened and closed, and the opening degree of the exhaust valve 2 can be detected by the opening degree detection sensor 5 with high accuracy.

  The present invention can be applied to other valve devices such as an EGR cooler passage switching valve device, an EGR injection amount control valve device, and a DPF regeneration valve device for collecting PM of a diesel engine.

It is a block diagram which shows the system configuration | structure of the exhaust system of the vehicle engine provided with the exhaust valve apparatus which concerns on this invention. It is a rear view of the exhaust valve device according to the present invention. It is a right view (figure of the arrow A direction of FIG. 1) of the exhaust valve apparatus which concerns on this invention. 1 is a perspective view of an exhaust valve device according to the present invention. It is a perspective view which removes and shows the water passage cover of the front of the exhaust valve device concerning the present invention. It is a rear view which shows the structure inside the drive case of the exhaust valve apparatus which concerns on this invention. 1 is an exploded perspective view of an exhaust valve device according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Exhaust valve apparatus 2 Exhaust valve 3 Valve body 3a Rectangular flange part of valve body 4 Drive case 5 Opening detection sensor (opening detection means)
6 Exhaust passage 7 Valve shaft 8 Valve body 9 Screw 10 Bolt 11 Heat insulating material 12 Electric motor 13 Pinion 14 Intermediate shaft 15 Large diameter gear 16 Small diameter gear 17 Sector gear 17a Sector gear boss 18 Return spring (biasing means)
19, 20 Cooling water passage 21 Communication hole 22, 23 Water passage cover 24 Screw 25, 26 Nipple 27 Screw 50 Engine 51 Intake manifold 52 Exhaust manifold 53 Catalytic converter 54 Muffler 60 Control device (ECU)
61 Engine rotation sensor 62 Water temperature sensor 63 Accelerator opening sensor 64 Load sensor

Claims (4)

An exhaust valve that pivotally supports a valve shaft on a valve body in which an exhaust passage is formed, and a valve body that opens and closes the exhaust passage is attached to the valve shaft;
A drive case containing an electric motor as a drive source and a gear for transmitting the rotation of the electric motor to the valve shaft;
An opening degree detecting means for detecting an opening degree of the exhaust valve;
In the exhaust valve device with
An exhaust valve device, wherein a cooling water passage is provided in a peripheral portion of the drive case.   2. The exhaust valve device according to claim 1, wherein the cooling water passages are respectively formed on two opposing surfaces of the drive case, and the two cooling water passages are communicated with each other.   The exhaust valve device according to claim 1 or 2, wherein a heat insulating material is sandwiched between the valve body and the drive case. The exhaust valve device according to any one of claims 1 to 3, further comprising an urging unit that urges the exhaust valve in the opening direction.

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