JP4352341B2 - Intake pipe pressure detection device for internal combustion engine - Google Patents

Description

  The present invention relates to an intake pipe pressure detection apparatus for an internal combustion engine, and more particularly to an apparatus for detecting an intake pipe pressure in an internal combustion engine having an independent throttle mechanism that opens and closes an intake passage for each intake pipe of each cylinder.

  Conventionally, as an operation control of an internal combustion engine, there is one that performs combustion control by detecting an intake pipe pressure of a cylinder and estimating an intake air amount. Further, an internal combustion engine provided with a so-called independent throttle mechanism in which a throttle valve is provided for each cylinder of a multi-cylinder internal combustion engine has been proposed that is configured to detect an average intake pipe pressure of each cylinder ( For example, see Patent Documents 1 and 2).

Here, FIG. 9 shows a conventional example of an intake device of a four-cylinder internal combustion engine provided with an independent throttle mechanism. In the conventional intake device 101, an air cleaner is connected on the upstream side, an intake manifold 110 having four intake pipes 111, one valve shaft 120, and four valves pivotally supported by the valve shaft 120. And a main body 130. Further, the intake device 101 is provided with a pressure introduction port 145 for each of the intake pipes 111 of the four cylinders, and an average intake pipe pressure of each cylinder is detected by a pressure detection unit 140 connected to each pressure introduction port 145 via a hose 146. Is configured to detect.
JP 7-77440 A JP-A-8-121233

  However, in the above-described conventional example, it is necessary to set the position of the pressure introduction port 145 provided in the intake pipe 111 of each cylinder so as not to interfere with the opening range of the valve body 130 that is a butterfly valve. The introduction port 145 must be positioned close to the combustion chamber of the internal combustion engine. Thereby, since the intake side volume of each cylinder becomes small, the detection of the average intake pipe pressure of each cylinder in the pressure detection unit 140 becomes extremely sensitive, and there is a problem that combustion control becomes difficult.

  In addition, it is necessary to set the pressure introduction port 145 for each cylinder, and the cost, mounting restrictions, assembly workability of parts such as the pressure introduction port 145 and the hose 146 connected to the pressure detection unit 140 are required. There are problems such as.

  The present invention has been made in view of the above-described problems, and is an internal combustion engine that can detect an average intake pipe pressure of each cylinder with high response and high accuracy with a simple structure in an internal combustion engine having an independent throttle mechanism. An object to be solved is to provide an intake pipe pressure detection device for an engine.

  Hereinafter, each means suitable for solving the above-described problems will be described with additional effects and the like as necessary.

1. An internal combustion engine intake pipe pressure detecting device for detecting an intake pipe pressure in an internal combustion engine having an independent throttle mechanism for opening and closing an intake passage for each intake pipe of each cylinder,
A hollow shaft-like member that is provided so as to bridge the intake pipes and is rotatably supported through a bearing, and an opening that communicates with the hollow part is provided on the outer peripheral surface for each of the intake pipes. Valve shaft,
A substantially disk-like member provided for each intake pipe of each cylinder and pivotally supported by the valve shaft, and a communication hole communicating with the opening of the valve shaft is provided on the surface of each cylinder combustion chamber. A plurality of valve bodies,
An intake pipe pressure detection device for an internal combustion engine, comprising: a pressure detection unit that is connected to the valve shaft and detects a pressure introduced through the hollow portion.

  According to the means 1, the valve shaft, which is a hollow shaft-like member that is provided so as to bridge the intake pipes and is rotatably supported via a bearing, has an opening that communicates with the hollow part for each intake pipe. Are provided on each outer peripheral surface, and are provided for each intake pipe of each cylinder and are substantially disk-shaped members that are pivotally supported by the valve shaft, each of which has a communication hole communicating with the opening of the valve shaft. Each of the intake pipe pressures is introduced into the hollow portion of the valve shaft through the communication hole of each valve body and the opening portion of the valve shaft, and is provided on the surface on the cylinder combustion chamber side, and is connected to the valve shaft. Detects the average intake pipe pressure of each cylinder introduced through the hollow portion. Therefore, since each intake pipe pressure is introduced at the valve body position, the intake side volume of each cylinder is maximized, and the average intake pipe pressure of each cylinder can be detected with good responsiveness and high accuracy. This facilitates combustion control of the internal combustion engine. In addition, since the valve shaft is used as both a shaft support and a pressure introduction of a plurality of valve bodies as a hollow shaft-like member, a pressure introduction port for connecting to a pressure introduction port and a pressure detection unit for each cylinder is used. There is no need to provide a hose or the like separately, and it is possible to reduce component costs and mounting restrictions and improve assembly workability.

  2. The first sealing member for sealing a gap between each intake pipe and the outer peripheral surface of the valve shaft is provided between adjacent intake pipes of each cylinder. An intake pipe pressure detection device for an internal combustion engine.

  According to the means 2, the first seal members for sealing the gaps between the respective intake pipes and the outer peripheral surface of the valve shaft are provided between the adjacent intake pipes of each cylinder. Airtightness at the connecting portion with the valve shaft can be ensured.

  3. Means 1 or 2 characterized in that a second seal member for sealing a gap between the pressure detection unit and the outer peripheral surface of the valve shaft is provided at a connection portion between the pressure detection unit and the valve shaft. An intake pipe pressure detection device for an internal combustion engine according to the description.

  According to the means 3, since the second seal member for sealing the gap between the pressure detection portion and the outer peripheral surface of the valve shaft is provided at the connection portion between the pressure detection portion and the valve shaft, the pressure detection portion and the valve Airtightness at the connecting portion with the shaft can be ensured.

  4). The intake pipe pressure detection device for an internal combustion engine according to any one of means 1 to 3, wherein the pressure detection unit is connected to an axial end of the valve shaft.

  According to the means 4, since the pressure detection part is connected to the axial end of the valve shaft, the connection part between the pressure detection part and the valve shaft can have a very simple structure, easily and inexpensively. Can be manufactured.

  5). The intake pipe pressure detection device for an internal combustion engine according to any one of means 1 to 3, wherein the pressure detection unit is connected to a substantially central portion in the axial direction of the valve shaft.

  According to the means 5, since the pressure detector is connected to the substantially central portion in the axial direction of the valve shaft, the average intake pipe pressure of each cylinder on both sides in the axial direction can be detected with higher accuracy.

  6). 6. The intake pipe pressure detection device for an internal combustion engine according to any one of means 1 to 5, wherein the communication hole of each valve body has an elongated hole shape.

  According to the means 6, since the communication hole of each valve body is in the shape of a long hole, it is possible to secure a large opening area and reduce pressure loss.

  7. 6. The intake pipe pressure detecting device for an internal combustion engine according to any one of means 1 to 5, wherein each valve body is provided with a plurality of communication holes.

  According to the means 7, each valve body is provided with a plurality of communication holes, so that a large opening area can be secured and pressure loss can be reduced.

  8). The intake pipe pressure detecting device for an internal combustion engine according to any one of means 1 to 7, wherein the valve shaft has at least a connecting portion with each of the valve main bodies formed in an irregular cross section.

  According to the means 8, since the valve shaft has at least a joint portion with each valve main body formed in an irregular cross section, each valve main body can be reliably prevented from rotating.

  9. The intake pipe pressure detecting device for an internal combustion engine according to any one of means 1 to 8, wherein the valve shaft is provided with an uneven shape on at least an outer peripheral surface of a coupling portion with each valve body.

  According to the means 9, since the valve shaft is provided with a concavo-convex shape at least on the outer peripheral surface of the coupling portion with each valve body, it is possible to reliably prevent the rotation of each valve body.

  Hereinafter, an embodiment of an intake device for a four-cylinder internal combustion engine to which an intake pipe pressure detection device for an internal combustion engine of the present invention is applied will be described with reference to the drawings. FIG. 1 is a diagram showing an overall configuration of an intake device 1 for a four-cylinder internal combustion engine according to the present embodiment. 2 is a cross-sectional view taken along line AA in FIG. 3 is a cross-sectional view taken along the line BB in FIG.

  The intake device 1 is mainly configured by an intake manifold 10 having four intake pipes 11, a valve shaft 20 and four valve bodies 30 constituting an independent throttle mechanism, and a pressure detection unit 40.

  The intake manifold 10 is provided with four intake pipes 11 connected to an upstream side of an air cleaner and branched in parallel toward the downstream side.

  The valve shaft 20 is a metal hollow shaft member having a D-shaped cross section having a hollow portion 20a extending in the axial direction. The valve shaft 20 connected to the pressure detection unit 40 is open at one end in the axial direction, the hollow portion 20a communicates with the outside, and is closed at the other end in the axial direction. The valve shaft 20 penetrates the four intake pipes 11 so as to bridge, and is rotatably supported via a pair of bearings 21 arranged with the four intake pipes 11 interposed therebetween. On the peripheral surface of the valve shaft 20, round hole-shaped openings 20 b communicating with the hollow portions 20 a are respectively provided at positions corresponding to the approximate centers of the four intake pipes 11. In addition, seal members 22 that seal the gap between the valve shaft 20 and the intake pipe 11 are provided on the outer peripheral surface of the valve shaft 20 between the adjacent intake pipes 11. Specifically, a rubber O-ring, Teflon packing, or the like can be suitably used as the seal member 22.

  The four valve bodies 30 are resin valve bodies having a substantially disk shape, and are respectively provided in the four intake pipes 11. Further, the four valve main bodies 30 are respectively supported by the valve shaft 20 by integrally molding synthetic resin with the valve shaft 20. Further, on the combustion chamber side (downstream of the intake pipe 11) of each cylinder of the valve main body 30, a round hole-shaped communication hole 30a is formed corresponding to the opening 20b of the valve shaft 20, and the opening 20b. And the communication hole 30a communicate with each other to form a pressure introduction port having a round hole shape for introducing the intake pipe pressure into the hollow portion 20a. The valve body 30 as a butterfly valve of each intake pipe 11 rotates at a predetermined angle together with the valve shaft 20 that is rotated by operating an accelerator pedal (not shown), and the same opening degree is set simultaneously. ing.

  The pressure detection unit 40 includes a box-shaped housing 41 having an internal space 41 a and a pressure sensor 42 that detects the pressure in the internal space 41 a of the housing 41. One end of the valve shaft 20 in the axial direction is hermetically connected to the opening 41b of the housing 41 via a seal member (not shown), and communication between the internal space 41a of the housing 41 and the hollow portion 20a of the valve shaft 20 is illustrated. It has been.

  As is clear from the above detailed description, according to the present embodiment, the valve is a hollow shaft-like member that is provided so as to bridge the intake pipes 11 and is rotatably supported via the bearing 21. The shaft 20 is provided with an opening 20 b communicating with the hollow portion 20 a for each intake pipe 11 on the outer peripheral surface, and is provided for each intake pipe 11 of each cylinder so as to be supported by the valve shaft 20. The four valve bodies 30 are each provided with a communication hole 30a communicating with the opening 20b of the valve shaft 20 on the surface of each cylinder combustion chamber, so that each valve body 30 as a pressure introduction port communicates with each other. Each intake pipe pressure is introduced into the hollow portion 20a of the valve shaft 20 through the hole 30a and the opening portion 20b of the valve shaft 20, and the pressure detector 40 connected to the valve shaft 20 Detecting an average intake pipe pressure of each cylinder is introduced through the section 20a. Accordingly, since each intake pipe pressure is introduced at the position of the valve body 30, the intake side volume of each cylinder is maximized, and the average intake pipe pressure of each cylinder can be detected with good responsiveness and high accuracy. This makes it easier to control the combustion of the internal combustion engine. Further, since the valve shaft 20 is used as both a shaft support and pressure introduction of the four valve main bodies 30 as a hollow shaft-like member, it is connected to the pressure introduction port and the pressure detection unit 40 for each cylinder. There is no need to separately provide a pressure introducing hose, etc., and it is possible to reduce component costs and mounting restrictions and to improve the assembly workability.

  Further, since the seal members 22 for sealing the gaps between the intake pipes 11 and the outer peripheral surface of the valve shaft 20 are provided between the intake pipes 11 adjacent to each cylinder, the intake pipes 11 and the valve shafts are provided. The airtightness in the connection part with 20 can be ensured.

  In addition, since a seal member that seals the gap between the casing 41 and the outer peripheral surface of the valve shaft 20 is provided at a connection portion between the pressure detection unit 40 and the valve shaft 20, the pressure detection unit 40 and the valve shaft 20 It is possible to ensure airtightness at the connecting portion. Since the pressure detector 40 is connected to the axial end of the valve shaft 20, the connecting portion between the pressure detector 40 and the valve shaft 20 can have a very simple structure, easily and inexpensively. Can be manufactured.

  Furthermore, since the valve shaft 20 has a D cross-sectional shape, it is possible to reliably prevent the rotation of each valve body 30 made of synthetic resin.

  In addition, this invention is not limited to embodiment mentioned above, A various change is possible in the range which does not deviate from the main point of this invention.

  For example, in the above-described embodiment, the opening 20b of the valve shaft 20 and the communication hole 30a of the valve main body 30 are each formed in a substantially round hole shape. However, as shown in FIG. 4, the opening 20b and the communication hole 30a are respectively long holes. Alternatively, as shown in FIG. 5, a plurality of openings 20 b and communication holes 30 a may be provided for each valve body 30. According to these modified examples, it is possible to secure a large opening area and reduce pressure loss.

  Further, in the embodiment, the example in which the valve shaft 20 has the D cross-sectional shape in order to prevent the rotation of each valve main body 30 is shown, but an irregular cross-sectional shape other than the D cross-section may be used. Alternatively, as shown in the modified example of FIG. 6, the valve shaft 20 has a circular cross-sectional shape, and at least the outer peripheral surface of the coupling portion with each valve body 30 is provided with an uneven shape by knurling or the like. You may make it stop.

  Moreover, in the said embodiment, although the pressure detection part 40 was set as the structure connected to the axial direction edge part of the valve shaft 20, it is good also as a structure which connects the pressure detection part 40 to the axial direction approximate center part of the valve shaft 20. FIG. 7 shows a modification in which the pressure detection unit 40 is connected to a substantially central portion in the axial direction of the valve shaft 20, and a seal member 43 is provided on the outer peripheral surface of the valve shaft 20 on both axial sides sandwiching the pressure detection unit 40. (O-ring) is provided. According to this modification, since the pressure detector 40 is provided at the substantially central portion in the axial direction of the valve shaft 20, the average intake pipe pressure of each cylinder on both sides in the axial direction can be detected with higher accuracy. FIG. 8 is an enlarged view of the vicinity of the pressure detection unit 40 according to another modification. A rubber oil seal is used as the seal member 43 so as to be in close contact with the outer peripheral surface of the valve shaft 20, and the valve Pressure is introduced into the internal space 41 a of the housing 41 through an opening 20 c as a pressure introduction port assembly provided in the shaft 20, and an average intake pipe pressure is detected by a pressure sensor 42.

  Moreover, in the said embodiment, although the example which used O-ring etc. which consist of rubber materials as a sealing member which seals the clearance gap with the valve shaft 20 was shown, Teflon packing, a mechanical seal (mechanical seal by a labyrinth structure), etc. are used. It is good also as a structure.

  In the above-described embodiment, an example of an intake device for a four-cylinder internal combustion engine has been described. However, the present invention can be applied to an internal combustion engine having a multi-cylinder independent throttle mechanism other than four cylinders.

  The present invention is applicable to an internal combustion engine having an independent throttle mechanism that opens and closes an intake passage for each intake pipe of each cylinder.

1 is an overall configuration diagram showing an intake device of a four-cylinder internal combustion engine that is an embodiment of the present invention. It is AA sectional drawing in FIG. It is BB sectional drawing in FIG. It is a figure which shows the modification which provided the pressure introduction port which consists of a long hole. It is a figure which shows the modification which provided the pressure introduction port which consists of a some round hole. It is a figure which shows the modification which provided uneven | corrugated shape in the outer peripheral surface of the valve shaft. It is a figure which shows the modification which has arrange | positioned the pressure detection part in the axial direction approximate center of the valve shaft. It is explanatory drawing which expands and shows the pressure detection part vicinity of the other modification which has arrange | positioned the pressure detection part in the axial direction approximate center of the valve shaft. It is a whole block diagram which shows the intake device of the 4-cylinder internal combustion engine of a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Intake apparatus of a 4-cylinder internal combustion engine 11 Intake pipe 20 Valve shaft 20a Hollow part 20b Opening part 21 Bearing 22 Seal member 30 Valve body 30a Communication hole 40 Pressure detection part

Claims (9)

An internal combustion engine intake pipe pressure detecting device for detecting an intake pipe pressure in an internal combustion engine having an independent throttle mechanism for opening and closing an intake passage for each intake pipe of each cylinder,
A hollow shaft-like member that is provided so as to bridge the intake pipes and is rotatably supported through a bearing, and an opening that communicates with the hollow part is provided on the outer peripheral surface for each of the intake pipes. Valve shaft,
A substantially disk-like member provided for each intake pipe of each cylinder and pivotally supported by the valve shaft, and a communication hole communicating with the opening of the valve shaft is provided on the surface of each cylinder combustion chamber. A plurality of valve bodies,
An intake pipe pressure detection device for an internal combustion engine, comprising: a pressure detection unit that is connected to the valve shaft and detects a pressure introduced through the hollow portion.   2. The first seal member for sealing a gap between each intake pipe and the outer peripheral surface of the valve shaft is provided between adjacent intake pipes of the cylinders. Intake pipe pressure detection device for internal combustion engine.   The second seal member for sealing a gap between the pressure detection unit and the outer peripheral surface of the valve shaft is provided at a connection portion between the pressure detection unit and the valve shaft. An intake pipe pressure detection device for an internal combustion engine according to claim 1.   The intake pipe pressure detection device for an internal combustion engine according to any one of claims 1 to 3, wherein the pressure detection unit is connected to an axial end of the valve shaft.   The intake pipe pressure detection device for an internal combustion engine according to any one of claims 1 to 3, wherein the pressure detection unit is connected to a substantially central portion in the axial direction of the valve shaft.   The intake pipe pressure detecting device for an internal combustion engine according to any one of claims 1 to 5, wherein the communication hole of each valve body has an elongated hole shape.   The intake pipe pressure detecting device for an internal combustion engine according to any one of claims 1 to 5, wherein each of the valve bodies is provided with a plurality of communication holes.   The intake pipe pressure detecting device for an internal combustion engine according to any one of claims 1 to 7, wherein the valve shaft has at least a joint portion with each of the valve bodies formed in an irregular cross-section.   The intake pipe pressure detection device for an internal combustion engine according to any one of claims 1 to 8, wherein the valve shaft is provided with an uneven shape on at least an outer peripheral surface of a joint portion with each valve body.

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