JP2014139422A - Variable valve device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a variable valve device capable of suppressing damage during assembly.SOLUTION: The prevent invention provides a variable valve device including: a drive shaft member 2 rotating synchronously with a crankshaft of an internal combustion engine; a cam shaft member 3 having a cam lobe 3a and rotatably provided around the drive shaft member 2; a drive arm portion 4 transmitting a rotational force from the drive shaft member 2 to the cam shaft member 3; a link member and a drive disk 5; a VVT 10 fixed to a tip end of the drive shaft member 2 via a bolt 12; a flange 2c2 or a drive arm 30 provided on the drive shaft member 2, and having a width-across-the-flats portion.

Description

  The present invention relates to a variable valve gear.

  2. Description of the Related Art Conventionally, a variable valve operating device that variably controls an operating angle of a cam that drives an intake valve or an exhaust valve mounted on an internal combustion engine (engine) is known. Patent Document 1 describes a variable valve operating device that obtains a desired cam rotation speed using an inconstant velocity joint.

JP-A-11-62531

  When assembling the variable valve gear, the parts are fixed using, for example, bolts. The parts are assembled while supporting the variable valve operating device with a tool. Damage to the variable valve operating device may occur due to a mechanical load applied in this process. An object of this invention is to provide the variable valve apparatus which can suppress the damage at the time of an assembly in view of the said subject.

  The present invention provides a drive shaft member that rotates in synchronization with a crankshaft included in an internal combustion engine, a camshaft having a cam lobe, and a cam shaft member that is rotatably provided around the drive shaft member. A transmission portion that transmits a rotational force to the camshaft member; a variable valve timing mechanism that is fixed to the tip of the drive shaft member using a fixing member; and a two-sided width portion that is fixed to the drive shaft member. This is a variable valve operating device.

  The said structure WHEREIN: The said 2 surface width part can be set as the structure which is a member integral with the said drive shaft member.

  The said structure WHEREIN: The said 2 surface width part can be set as the structure fixed directly to the said drive shaft member.

  The said structure WHEREIN: The said 2 surface width part can be set as the structure provided in the bearing part of the said drive shaft member.

  The said structure WHEREIN: It can be set as the structure by which the said 2 surface width part is provided in the bearing part nearest to the said variable valve timing mechanism among several said bearing parts.

  In the above configuration, the cam shaft member includes a cam lobe and is provided rotatably around the drive shaft member, and a transmission unit that transmits the rotational force from the drive shaft member to the cam shaft member. The width across flats may be provided in the transmission unit.

  The said structure WHEREIN: It can be set as the structure by which the said 2 surface width part is provided in the transmission part nearest to the said variable valve timing mechanism among the said some transmission parts.

  ADVANTAGE OF THE INVENTION According to this invention, the variable valve apparatus which can suppress the damage at the time of an assembly can be provided.

1 is a perspective view illustrating a variable valve operating apparatus according to a first embodiment. FIG. 2A-1 is a perspective view of the control sleeve. FIG. 2A-2 is a perspective view of the control sleeve viewed from a direction different from that in FIG. 2B-1 is a left side view of the control sleeve, FIG. 2B-2 is a front view of the control sleeve, and FIG. 2B-3 is a right side view of the control sleeve. FIG. 3A is a perspective view illustrating a drive shaft member. FIG. 3B is an enlarged perspective view of the distal end portion of the drive shaft member. FIG. 4A is a perspective view illustrating a drive shaft member according to the second embodiment. FIG. 4B is an enlarged perspective view of the distal end portion of the drive shaft member in a modification of the second embodiment. FIG. 5 is a perspective view illustrating the variable valve operating apparatus according to the third embodiment. FIG. 6 is a perspective view illustrating a drive shaft member according to the third embodiment. FIG. 7A is a perspective view illustrating a drive arm unit according to the third embodiment. FIG. 7B is a perspective view illustrating a drive shaft member in the third embodiment. FIG. 7C is a perspective view illustrating a cross section of the drive shaft member according to the third embodiment.

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

  FIG. 1 is a perspective view illustrating a variable valve apparatus 100 according to the first embodiment. As shown in FIG. 1, the variable valve apparatus 100 includes drive shaft members 2 and 22 that rotate in synchronization with a crankshaft included in the internal combustion engine, and a cam housing 20. The drive shaft members 2 and 22 are mounted on the cam housing 20. The drive shaft member 2 is provided correspondingly to an unillustrated intake valve, and the drive shaft member 22 is provided corresponding to an unillustrated exhaust valve.

  As shown in FIG. 1, the variable valve gear 100 includes a cam shaft member 3 that is rotatably provided around the drive shaft member 2. The cam shaft member 3 has a cam lobe 3a. The variable valve operating apparatus 100 includes a drive arm unit 4 that is provided on the drive shaft member 2 and rotates together with the drive shaft member 2. The variable valve operating apparatus 100 includes a drive disk 5 and a control sleeve 8. The control sleeve 8 is provided with an eccentric hole 8a (described later). The drive disk 5 rotates along the inner peripheral wall surface of the eccentric hole 8 a provided in the control sleeve 8.

  The cam shaft member 3 is a cylindrical member, and includes two cam lobes 3a corresponding to the number of intake valves for each cylinder. The cam shaft member 3 is rotatably provided around the drive shaft member 2 so that the rotation center axis of the cam shaft member 3 coincides with the center axis of the drive shaft member 2. One end of a second link member 6b is connected to the cam lobe 3a. The camshaft member 3 is prepared for each of the cylinders # 1 to # 4 and is rotatably provided around the drive shaft member 2 as shown in FIG. The cam lobe 3a abuts against a rocker roller provided in a rocker arm (not shown) and lifts the intake valve. A two-surface width portion 3 b is provided on the outer peripheral surface of the cam shaft member 3. By engaging a tool such as a spanner with the two-surface width portion 3b, the cam shaft member 3 can be easily held in the assembly process of the variable valve apparatus 100. In Examples 1 to 3, the width across flats means a part having opposing sides.

  The drive arm unit 4 is a cylindrical member. The central axis of the drive arm portion 4 coincides with the central axis of the drive shaft member 2. The drive arm portion 4 is fixed to the drive shaft member 2 by pins or the like, for example, and rotates together with the drive shaft member 2. The drive arm portion 4 is connected to one end of the first link member 6a as will be described later. The drive arm unit 4 is prepared for each of the cylinders # 1 to # 4.

  The first link member 6a and the second link member 6b have the same shape. Each of the first link member 6a and the second link member 6b includes two pin insertion holes (not shown). The first link member 6 a and the second link member 6 b (collectively referred to as link members) are link members that transmit the rotation of the drive arm portion 4 to the camshaft member 3 via the drive disk 5. One end of the first link member 6 a is connected to the drive arm unit 4 using a pin, and the other end is connected to the drive disk 5. Thereby, the rotation of the drive arm unit 4 is transmitted to the drive disk 5.

  The second link member 6 b has one end connected to the drive disk 5 using a pin and the other end connected to the cam shaft member 3. Thereby, the rotation of the drive disk 5 is transmitted to the cam shaft member 3. Thus, the first link member 6 a and the second link member 6 b transmit the rotation of the drive arm portion 4 to the cam shaft member 3 via the drive disk 5. The drive arm unit 4, the link member, and the drive disk 5 function as a transmission unit that transmits a rotational force from the drive shaft member 2 to the cam shaft member 3.

  FIG. 2A-1 is a perspective view of the control sleeve 8. FIG. FIG. 2A-2 is a perspective view of the control sleeve 8 viewed from a direction different from that in FIG. 2B-1 is a left side view of the control sleeve 8, FIG. 2B-2 is a front view of the control sleeve 8, and FIG. 2B-3 is a right side view of the control sleeve 8. FIG.

  The control sleeve 8 includes an eccentric hole 8a and a cylindrical portion 8c, and a gear portion 8b on the outer peripheral surface. The rotation center axis AX1 of the control sleeve 8 coincides with the center axis of the inner circumferential circle of the cylindrical portion 8c. The rotation center axis AX1 is different from the center axis AX2 of the eccentric hole 8a. The drive shaft member 2 is inserted through the eccentric hole 8a and the cylindrical portion 8c. Here, the central axis of the drive shaft member 2 inserted through the eccentric hole 8a and the cylindrical portion 8c and the rotation center axis AX1 of the control sleeve 8, that is, the central axis of the cylindrical portion 8c coincide. The drive disk 5 is rotatably mounted in the eccentric hole 8a through, for example, a bearing. The bearing is interposed between the cylindrical portion 8c and the drive shaft member 2, so that the drive shaft member 2 is supported in the cylindrical portion 8c. As shown in FIG. 2B-2, the gear portion 8 b meshes with a gear portion 15 a provided on the outer peripheral surface of the control shaft 14 and rotates the control sleeve 8 as the control shaft 14 rotates. As the control sleeve 8 rotates, the position of the central axis AX2 of the eccentric hole 8a changes, and the operating angle changes.

  FIG. 3A is a perspective view illustrating the drive shaft member 2. FIG. 3B is an enlarged perspective view of the distal end portion of the drive shaft member 2. As shown in FIGS. 3A and 3B, the drive shaft member 2 includes a VVT (Variable Valve Timing) mounting portion 2a and a bearing portion 2b at the front end. The bearing portion 2b includes flanges 2c1 and 2c2 and a contact surface 2d. The VVT mounting portion 2a, the flanges 2c1 and 2c2, and the contact surface 2d are members formed integrally with the drive shaft member 2. A VVT (variable valve timing mechanism) 10 is mounted on the VVT mounting portion 2a. The VVT 10 includes a hole 10a at the center. The VVT 10 is fixed to the VVT mounting portion 2a using, for example, a bolt 12 (fixing member) inserted into the hole 10a. The VVT 10 is fixed to the pulley 11. A timing chain (not shown) is suspended from the pulley 11. The rotation of the crankshaft (not shown) is transmitted to the pulley 11 via the timing chain. Further, the rotation is transmitted to the drive shaft member 2 through the pulley 11 and the VVT 10. Thus, the drive shaft member 2 rotates in synchronization with the crankshaft. A VVT 24 is also attached to the drive shaft member 22. The drive shaft member 22 rotates by the same mechanism as the drive shaft member 2. In the VVTs 10 and 24, vanes (not shown) are provided. By using the VVTs 10 and 24, the valve timings of the intake valve and the exhaust valve can be made variable.

  The contact surface 2 d contacts the cam housing 20. The contact surface 2d is sandwiched between two flanges 2c1 and 2c2. The flanges 2c1 and 2c2 project in the radial direction of the drive shaft member 2, and are used for positioning the drive shaft member 2 in the axial direction. The contact surface 2d is placed on the cam housing 20, and the flanges 2c1 and 2c2 sandwich the cam housing 20 from both sides in the central axis direction, whereby the drive shaft member 2 is positioned. The flange 2c1 is circular. The flange 2c2 is a two-sided width portion having a regular hexagonal shape that goes around the drive shaft member 2, for example.

  The flange 2c2 engages with tools such as a spanner and a wrench. For this reason, when the VVT 10 is assembled, the drive shaft member 2 can be fixed by supporting the flange 2c2 with a tool. The flange 2 c 2 is a member integrated with the drive shaft member 2. For this reason, the load is applied to the drive shaft member 2, and the load is hardly applied to other components such as the drive arm portion 4, the drive disk 5, the link member, and the control sleeve 8. Therefore, it is possible to suppress damage to the variable valve apparatus 100. In particular, damage to the drive arm unit 4, the drive disk 5, the link member, and the control sleeve 8 is suppressed. Therefore, a desired working angle can be obtained.

  For example, the VVT 10 may be mounted while supporting the two-surface width portion 3b of the cam shaft member 3 with a tool. However, the cam shaft member 3 is connected to the drive shaft member 2 via other components, such as the drive arm portion 4, the link member, and the drive disk 5. Accordingly, a load is also applied to the drive arm unit 4, the link member, and the drive disk 5. Therefore, these parts may be damaged. This makes it difficult to obtain a desired operating angle. In particular, the bolt 12 is tightened when the VVT 10 is mounted. For this reason, a large load is applied to the drive shaft member 2. According to Example 1, damage can be effectively suppressed.

  Further, if the two-surface width portion 3b of the cam shaft member 3 of the cylinder # 1 is supported by a tool, the drive arm portion 4, the link member, and the drive disk 5 may be deformed in the cylinder # 1. As a result, the operating angle may vary between the cylinders. According to the first embodiment, deformation of the drive arm portion 4, the link member, and the drive disk 5 is suppressed. Therefore, variation in the operating angle between the cylinders is suppressed.

  For example, the bearing portion 2b may be provided on the rear end side (cylinder # 4 side) of the drive shaft member 2. The drive shaft member 2 may be fixed by supporting the flange 2c2 provided on the rear end side with a tool, and the VVT 10 may be mounted. However, when the distance between the VVT mounting portion 2a located on the front end side and the flange 2c2 increases, the load applied to the drive shaft member 2 increases. For this reason, there is a high possibility that plastic deformation occurs. Therefore, it is preferable that the flange 2c2 is provided on the bearing 2b closest to the VVT 10. Thereby, a load can be made smaller and plastic deformation can be suppressed.

  The flange 2c2 may have a regular polygonal shape such as a square or a regular octagon other than a regular hexagon. In particular, when the flange 2c2 has an even number of apexes, two opposing sides are parallel to each other, and a tool can be engaged with these two sides. The flange 2c2 may have a polygonal shape other than a regular polygon, as long as it has a shape with which a tool can be engaged. What is necessary is just to determine the two-surface width of the flange 2c2 according to the tool to be used.

  The second embodiment is an example in which the flange 2c2 is modified. FIG. 4A is a perspective view illustrating the drive shaft member 2 in the second embodiment.

  As shown in FIG. 4A, the flange 2c2 includes a disk portion 2e and a two-sided width portion 2f. The disk portion 2 e and the two-surface width portion 2 f are members integrated with the drive shaft member 2. Similarly to the first embodiment, the drive shaft member 2 can be fixed by supporting the two-surface width portion 2f. Therefore, damage is suppressed.

  FIG. 4B is an enlarged perspective view of the distal end portion of the drive shaft member 2 in a modification of the second embodiment. As shown in FIG. 4B, the two-surface width portion 2 f can be a member different from the drive shaft member 2. The two-surface width portion 2f is a plate-like member having, for example, a regular hexagon, and is fixed to the flange 2c2 with screws 2g or the like. Thus, the two-surface width portion 2f is provided directly on the drive shaft member 2 without any other components. Therefore, the load is hardly applied to components such as the drive arm portion 4, the drive disk 5, and the control sleeve 8. Therefore, damage is suppressed. The two-sided width portion 2f may be fixed to the flange 2c2 by, for example, press fitting.

  The third embodiment is an example in which the drive arm portion 30 has a two-sided width portion 30a. FIG. 5 is a perspective view illustrating a variable valve apparatus 300 according to the third embodiment. FIG. 6 is a perspective view illustrating the drive shaft member 2 according to the third embodiment.

  As shown in FIGS. 5 and 6, a drive arm portion 30 is provided corresponding to the cylinder # 1. A drive arm portion 4 is provided corresponding to the cylinders # 2 to # 4. Moreover, as shown in FIG. 6, the flange 2c2 is disk shape, for example.

  FIG. 7A is a perspective view illustrating the drive arm unit 30 according to the third embodiment. FIG. 7B is a perspective view illustrating the drive shaft member 2 in the third embodiment. FIG. 7C is a perspective view illustrating a cross section of the drive shaft member 2 in the third embodiment.

  The drive arm portion 30 includes a two-sided width portion 30a and holes 30b, 30c and 30d. The drive shaft member 2 is inserted into the hole 30b. A pin 32 is inserted into the hole 30c. The pin 32 penetrates the drive shaft member 2 and the drive arm portion 30, so that the drive arm portion 30 is directly fixed to the drive shaft member 2. The drive arm 30 and the first link member 6a are connected by inserting the pin 34 into the hole 30d.

  The drive shaft member 2 can be fixed by engaging a tool with the two-surface width portion 30 a of the drive arm portion 30. The drive arm portion 30 is provided directly on the drive shaft member 2. For this reason, almost no load is applied to other components such as the drive disk 5 and the control sleeve 8. It is possible to suppress damage to the variable valve operating apparatus in assembling the VVT 10.

  The drive arm unit 30 may be provided corresponding to the cylinders # 2 to # 4. However, in order to reduce the load and suppress plastic deformation, it is preferable to provide the drive arm portion 30 corresponding to the cylinder # 1 closest to the VVT 10. That is, it is preferable that the two-surface width portion 30a is formed on the drive arm portion closest to the VVT 10.

  As shown in the first and second embodiments, the width across flats only needs to be fixed to the drive shaft member 2. “Fixed” means that it is integrated with the drive shaft member 2 or directly provided on the drive shaft member 2. That is, the two-surface width portion rotates integrally with the drive shaft member 2.

  Although the embodiments of the present invention have been described in detail above, the present invention is not limited to such specific embodiments, and various modifications and changes can be made within the scope of the gist of the present invention described in the claims. It can be changed.

2 Drive shaft member 2b Bearing portion 2c1, 2c2 Flange 2f, 3b, 30a Two-sided width portion 3 Cam shaft member 3a Cam lobe 4, 30 Drive arm portion 5 Drive disk 6a First link member 6b Second link member 8 Control sleeve 10 VVT
12 bolt 14 control shaft

Claims (7)

A drive shaft member that rotates in synchronization with a crankshaft included in the internal combustion engine;
A camshaft member having a cam lobe and rotatably provided around the drive shaft member;
A transmission portion for transmitting a rotational force from the drive shaft member to the cam shaft member;
A variable valve timing mechanism fixed to the tip of the drive shaft member using a fixing member;
And a two-surface width portion fixed to the drive shaft member.   The variable valve operating apparatus according to claim 1, wherein the two-surface width portion is a member integrated with the drive shaft member.   The variable valve operating apparatus according to claim 1, wherein the two-surface width portion is provided directly on the drive shaft member.   4. The variable valve operating apparatus according to claim 1, wherein the two-surface width portion is provided in a bearing portion of the drive shaft member. 5.   5. The variable valve operating apparatus according to claim 4, wherein the two-surface width portion is provided in a bearing portion closest to the variable valve timing mechanism among the plurality of bearing portions. The transmission unit includes a member provided directly on the drive shaft member,
4. The variable valve operating apparatus according to claim 3, wherein the width across flats is provided on the member.   The variable valve operating apparatus according to claim 6, wherein the two-surface width portion is provided in a transmission portion closest to the variable valve timing mechanism among the plurality of transmission portions.

Images