JP2017014942A - Valve opening/closing timing control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a valve opening/closing timing control device using an aluminum material, which is favorable in the accuracy of phase control and long in a belt life.SOLUTION: A valve opening/closing timing control device, comprises: a drive-side rotating body A which rotates synchronously with a crankshaft Z of an internal combustion engine; a driven-side rotating body B which rotates integrally with a camshaft C of the internal combustion engine, and is relatively rotatable with respect to the drive-side rotating body A inside the drive-side rotating body A; a fluid pressure chamber R which is formed of the drive-side rotating body A and the driven-side rotating body B; and partitioning parts 1, 2 which partition the fluid pressure chamber R into a retardation chamber and an advance chamber. The drive-side rotating body A comprises: an aluminum housing H having a pulley P for receiving a drive force of the crankshaft Z via a drive belt V; and plates FP, RP which are attached to at least one face of the housing H. A clearance G from which fluid can flow is formed between the housing H and the plates FP, RP.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a valve opening / closing timing control device that adjusts the ignition timing of an internal combustion engine, and more particularly to a drive-side rotating body having a pulley that receives a driving force from a crankshaft and made of an aluminum material.

  As described above, for example, Japanese Patent Application Laid-Open No. H10-228707 discloses a drive side rotating body of the valve opening / closing timing control device made of an aluminum material. Here, after the aluminum material is extruded from the mold and subjected to primary processing for adjusting the shape, the entire outer peripheral surface and inner peripheral surface are subjected to alumite treatment to increase the hardness of each surface. According to the known document, the weight of the apparatus can be reduced by using an aluminum-type metal material. In addition, since the drive-side rotator is manufactured by extrusion molding, the hydraulic oil is prevented from oozing from the inside of the drive-side rotator to the pulley formed outside the drive-side rotator, and deterioration of the rubber belt can be prevented ([ [0017] [0193] Paragraph).

JP 2010-203234 A

  In the technique of Patent Document 1, although the surface hardness of the driving side rotating body is increased by the alumite treatment, for example, the surface roughness of the pulley tooth portion is deteriorated. If an attempt is made to increase the film thickness of the alumite treatment in order to improve the wear resistance of the pulley tooth portion, the surface roughness will be further deteriorated. As a result, the belt wound around the pulley is easily damaged, and the life of the belt is shortened.

  Further, the pulley is formed so as to protrude from the main body of the driving side rotating body in the radially outward direction. For this reason, the deformation of the pulley caused by the tension of the belt is transmitted to the main body of the driving side rotating body, and the main body may be deformed. A vane provided on the driven side rotator slides on the inner peripheral surface of the main body to form an advance chamber and a retard chamber. Therefore, the contact property of the vane deteriorates due to the deformation of the main body, the advance chamber and the retard chamber communicate with each other, and the valve opening / closing timing cannot be accurately controlled.

  Furthermore, the main body integrally formed with the pulley, and the front plate and the rear plate are fastened by using bolts, but when the fastening force of the bolt acts on the contact surface between both plates and the main body, the main body is deformed. There is. As a result, the pulley is deformed, the tooth accuracy is deteriorated, the life of the drive belt is further shortened, and noise of the drive belt is generated.

  In view of the above situation, as such a valve opening / closing timing control device, there is a demand for a device having high phase control accuracy and a long belt life while using an aluminum material.

The characteristic configuration of the valve timing control device according to the present invention is:
A drive-side rotating body that rotates around the axis of rotation while rotating synchronously with the crankshaft of the internal combustion engine;
A driven-side rotating body that rotates integrally with the camshaft of the internal combustion engine around the rotating shaft core and is rotatable relative to the driving-side rotating body inside the driving-side rotating body;
A fluid pressure chamber formed by the driving side rotating body and the driven side rotating body;
The fluid pressure chamber is disposed in the fluid pressure chamber, and the fluid pressure chamber is divided into a retard angle chamber and an advance angle chamber that allow inflow or discharge of fluid, and the relative rotation phase of the driven side rotating body with respect to the driving side rotating body is determined as the inflow of fluid. A partition part that selectively moves between a retarding direction in which the volume in the retarding chamber increases and an advancing direction in which the volume in the advanced chamber increases due to the inflow of fluid;
A phase control unit that controls supply of fluid to the retard chamber and discharge of fluid from the advance chamber, or discharge of fluid from the retard chamber and supply of fluid to the advance chamber. ,
The drive-side rotator is attached to an aluminum housing having a pulley to which a driving force from the crankshaft is input via a drive belt, and at least one surface of the housing along the rotation axis. Plate with
A gap is provided between the housing and the plate so that fluid can flow out.

  When the pulley and the housing of the driving side rotating body are formed of an aluminum material, the material itself is relatively soft, so that the pulley is easily worn by friction with the driving belt.

  Therefore, in this configuration, a gap is provided between the aluminum housing and the plate so that the internal fluid can flow out. As a result, the fluid flows out of the gap as the driving side rotator rotates, and the fluid flows outward by centrifugal force. The fluid reaches the pulley outside the housing and the drive belt wound around the pulley, and lubricates the contact portion between the pulley and the drive belt. With this configuration, the wear of the pulley and the drive belt can be reduced, and a highly reliable valve opening / closing timing control device can be obtained.

  In the valve opening / closing timing control device according to the present invention, it is advantageous that the pulley is anodized.

  As in this configuration, the surface strength of the pulley can be increased by anodizing the pulley. However, the alumite treatment increases the surface strength of the pulley, but the surface shape of the pulley becomes rough as the alumite layer grows, and the aggressiveness against the drive belt wound around the pulley is increased. However, since the wear of the drive belt and the pulley is reduced by the fluid supplied from the gap, the reliability of the valve opening / closing timing control device is not impaired.

  In the valve timing control apparatus according to the present invention, at least one of the contact surfaces of the housing or the plate is an anodized surface having a predetermined surface roughness, and the contact between the housing and the plate is achieved. It can comprise so that a surface may contact | abut directly.

  In the valve opening / closing timing control device of the present invention, the fluid is allowed to flow out through a gap provided at the contact portion between the housing and the plate. For this reason, in this configuration, at least one of the housing and the plate is made of an aluminum material, and at least one of the mutual contact surfaces is an anodized surface. In other words, an alumite treatment is performed to increase the surface roughness of the contact surface, and the housing and the plate are directly contacted to form the gap. In addition, since the strength of the contact surface subjected to the alumite treatment is increased, it is possible to prevent deformation of the driving side rotating body and to obtain a highly reliable valve opening / closing timing control device.

  In this way, by performing the alumite treatment on the housing and the plate, it is possible to efficiently form a drive side rotating body capable of flowing out the fluid. In particular, when the abutting surface of the housing is alumite-treated, the pulley and the abutting surface can be alumite-treated at the same time, and the efficiency of creating the gap can be further improved. Further, since the housing and the plate are brought into direct contact with each other, there is no need to provide a seal member or the like between them, and the configuration of the drive side rotating body is simplified.

  In the valve opening / closing timing control device according to the present invention, the partition portion is provided on the driven-side rotating body, and the housing has a cylindrical wall portion having an inner peripheral surface with a sliding contact region in sliding contact with the partition portion. In addition, a groove portion is formed between the pulley and the cylindrical wall portion so as to penetrate in the direction of the rotary shaft core and extend in a circumferential direction with respect to the rotary shaft core. It can comprise so that it may have an overlap area | region along the radial direction of the said rotating shaft core.

  Aluminum housings are softer than steel ones, and some deformation may occur when the driving force from the crankshaft is input to the pulley via the drive belt. As a result, for example, the cylindrical wall portion of the housing is distorted, and a gap is generated between the partition portion and the inner peripheral surface that are to be in sliding contact with the inner peripheral surface of the cylindrical wall portion. Fluid leakage occurs between the advance chamber and the retard chamber, and the phase control of the valve timing control device becomes inaccurate.

  Therefore, as shown in this configuration, a groove is provided between the pulley and the cylindrical wall, and the pulley is deformed by configuring the partition and the sliding contact area of the housing and the groove to overlap in the radial direction. Even in this case, it is possible to prevent the deformation from being transmitted to the cylindrical wall portion of the housing. As a result, a valve opening / closing timing control device that can perform accurate phase control can be obtained.

  In the valve timing control apparatus according to the present invention, the width of the groove portion along the radial direction of the rotating shaft core can be formed to be equal to or greater than the width of the contact surface of the housing along the radial direction.

  The housing of this structure is produced by extrusion molding of an aluminum material, for example. Therefore, by setting the width of the groove portion to the extent of this configuration, the pulley is positioned outward from the outer surface of the cylindrical wall portion, the pulley is formed to a predetermined outer diameter, and the extrusion amount of the aluminum material is increased. It can be reduced by the amount of the groove.

It is a sectional side view of the valve timing control apparatus of this embodiment. It is a plane sectional view of the valve timing control device of this embodiment. It is a disassembled perspective view of the drive side rotary body of this embodiment.

〔overall structure〕
Embodiments of the present invention will be described below with reference to the drawings.
The characteristic configuration of the valve timing control apparatus according to the present invention is shown in FIGS. FIG. 1 is a side sectional view of the apparatus, FIG. 2 is a plan sectional view, and FIG. 3 is an exploded perspective view of a driving side rotating body.

  The valve opening / closing timing control device is mainly provided inside a driving side rotating body A and an outer side of a driving side rotating body A (outer rotor) rotating around a rotation axis X while rotating synchronously with a crankshaft Z of an internal combustion engine. A driven side rotating body B (inner rotor) that rotates integrally with the cam shaft C of the internal combustion engine around the rotation axis X, and a phase control unit that adjusts the relative rotational phase of the driving side rotating body A and the driven side rotating body B; Consists of.

  A fluid pressure chamber R is formed between the driving side rotating body A and the driven side rotating body B. The 1st convex part 1 which protruded inward from the outer side drive side rotary body A contact | abutted to the outer peripheral surface B1 of the inner driven side rotary body B, and the 2nd convex part which protruded from the outer peripheral surface B1 of the driven side rotary body B 2 abuts against the inner peripheral surface W1 of the drive side rotator A. The first convex portion 1 and the second convex portion 2 function as a partition portion for the fluid pressure chamber R, and partition the fluid pressure chamber R into an advance chamber R1 and a retard chamber R2.

  By supplying the working fluid from the advance oil passage 3 to the advance chamber R1 and discharging the working fluid from the retard chamber R2 via the retard oil passage 4, the driven side rotator B rotates clockwise in FIG. Relative rotation. As a result, the valve opening / closing timing of the internal combustion engine is accelerated. For example, such an advance operation is performed when the rotational speed of the internal combustion engine is increased. On the other hand, by supplying the working fluid to the retard chamber R2 and discharging the working fluid from the advance chamber R1, the driven-side rotator B relatively rotates counterclockwise in FIG. As a result, the valve opening / closing timing of the internal combustion engine is delayed. This is performed, for example, when the rotational speed of the internal combustion engine is lowered, and the operation by idle rotation is performed at the most retarded phase.

〔housing〕
In the present embodiment, the housing H of the drive side rotator A is made of an aluminum material. The drive side rotator A is mainly composed of three members. A housing H integrally formed with a pulley P on the outer peripheral portion, a front plate FP sandwiching the housing H from both sides, and a rear plate RP. These are assembled together using a plurality of fastening bolts 5. As shown in FIG. 3, the housing H has substantially the same cross-sectional shape in the fastening direction, and is manufactured, for example, by extrusion molding of an aluminum material. As another configuration, the front plate FP or the rear plate RP can be integrally formed with the housing H. In that case, it is good to manufacture by the die-casting method etc.

  In particular, the housing H has a pulley P formed on the outer peripheral side, and a cylindrical wall portion W on the inner peripheral side for accommodating the driven side rotating body B. The cylindrical wall portion W has an inner peripheral surface W1 with which the second convex portion 2 formed on the driven side rotating body B is in sliding contact. The cylindrical wall portion W has a plurality of first convex portions 1 that are in sliding contact with the outer peripheral surface B1 of the driven side rotating body B.

  As shown in FIG. 2, a pulley P is integrally formed on the outer peripheral side of the cylindrical wall portion W so as to be mostly separated from the cylindrical wall portion W. The cylindrical wall portion W and the pulley P are connected by connecting portions 6 provided at the same positions as the four first convex portions 1 that are dispersedly arranged along the circumferential direction.

  As described above, when the cylindrical wall portion W and the pulley P are integrally formed, the labor of aligning both of them is not required as compared with the case where they are individually configured and connected. In addition, the fastening bolt 5 that integrates the two is not necessary, and the fastening work itself is not required, and the effects of weight reduction and cost reduction can be obtained.

[Bolt fastening]
As shown in FIGS. 2 and 3, the bolt hole 7 formed in the housing H so as to insert the fastening bolt 5 is provided at the center position of the first convex portion 1. In this way, a wide contact area between the front plate FP or the rear plate RP and the housing H is ensured, and a local load is not applied to the housing H when the fastening bolt 5 is fastened. As a result, the front plate FP, the rear plate RP, and the housing H are not easily deformed, and the working fluid held in the fluid pressure chamber R leaks unnecessarily to the outside from between the front plate FP and the housing H, for example. It can be prevented from coming out.

  The front plate FP and the rear plate RP can also be made of an aluminum material. With such a configuration, the drive-side rotator A can be further reduced in weight. In particular, when the rear plate RP is made of an aluminum material, the female screw portion 8 with which the fastening bolt 5 is engaged should be slightly lengthened to prevent the female screw portion 8 from being damaged by the fastening force.

  Moreover, the position of the internal thread part 8 is an intermediate position between the 1st convex part 1 and the connection part 6 along a radial direction, as shown in FIG. More specifically, the position is slightly closer to the first convex portion 1 side. If it is this position, when the 2nd convex part 2 of driven side rotator B will reach the most advanced angle phase and the most retarded angle phase and will contact the 1st convex part 1, bend deformation of the 1st convex part 1 will be carried out. Can be prevented. Incidentally, in the example of FIG. 2, only the second convex part 2 at the upper left in the figure is configured to abut on the first convex part 1.

〔Alumite treatment〕
When the pulley P and the housing H of the driving side rotating body A are made of an aluminum material which is a relatively soft material, the pulley P is easily worn by friction with the driving belt V. Therefore, the drive side rotator A is subjected to an anodic oxidation treatment, so-called alumite treatment, to increase the surface hardness. In particular, the tooth part of the pulley P and the side surface of the cylindrical wall part W are objects.

  However, when the alumite treatment is performed, the surface roughness of the treated portion surface is deteriorated. Therefore, the aggressiveness such as an increase in the coefficient of friction with respect to the drive belt V increases, and conversely, the life of the drive belt V may be reduced.

[Gap]
Therefore, in the present embodiment, as shown in FIGS. 2 and 3, a working fluid for lubrication is supplied to the drive belt V from between the housing H, the front plate FP, and the rear plate RP.

  Specifically, a gap G is provided between the housing H and the front plate FP and the rear plate RP so that oil as a working fluid can flow out. The gap G is formed, for example, by increasing the surface roughness of the abutting surface W2 that abuts the front plate FP or the rear plate RP on the surface of the housing H by the alumite treatment.

  The contact surface W2 of the housing H and the contact surface FP1 of the front plate FP or the contact surface RP1 of the rear plate RP are brought into direct contact with each other.

  Accordingly, an appropriate amount of oil flows out of the gap as the drive side rotator A rotates, and flows outward by centrifugal force. The flowing oil reaches the pulley P outside the housing H and the drive belt V wound around the pulley P, and lubricates the drive belt V. Of course, the drive belt V is made of a material suitable for oil lubrication.

  Moreover, the surface hardness of the contact surface W2 is increased by subjecting the contact surface W2 to an alumite treatment. Therefore, it is possible to prevent the cylindrical wall portion W from being deformed even when the fastening force of the fastening bolt 5 is excessive when fastening the front plate FP and the rear plate RP.

  Furthermore, with this configuration, it is not necessary to provide a special sealing material between the cylindrical wall portion W and the front plate FP or the rear plate RP, and the configuration of the drive side rotating body A is simplified.

  As described above, the driving side rotating body A having this configuration reduces the wear of the pulley P and the driving belt V while simplifying the structure of the driving side rotating body A, and provides a highly reliable valve opening / closing timing control device. Can be obtained.

  In order to form the gap G, the front plate FP or the rear plate RP is formed of an aluminum material, and the contact surface FP1 of the front plate FP or the contact surface RP1 of the rear plate RP is anodized. The surface roughness of these contact surfaces may be increased.

[Groove]
In the drive side rotating body A of the present embodiment, a groove portion 9 that penetrates in the direction of the rotation axis X and extends in the circumferential direction with respect to the rotation axis X is formed between the pulley P and the cylindrical wall portion W. It is. In the example shown in FIG. 2, the groove portion 9 is formed over the entire region that is not the connection portion 6 that connects the cylindrical wall portion W and the pulley P.

  An end portion of the groove portion 9 in the circumferential direction reaches the center side of the first convex portion 1 rather than the side surface of the first convex portion 1. That is, the length along the circumferential direction of each connection portion 6 that is the region sandwiched between the groove portions 9 is shorter than the length along the circumferential direction of the first convex portion 1 corresponding to each connection portion 6. Has been. This is because the drive belt V is used as a pulley to secure a wide area of the groove 9 with respect to an area where the second convex portion 2 of the driven side rotating body B is in sliding contact with the inner peripheral surface W1 of the cylindrical wall portion W. This is because even when P is deformed, the position where the deformation is transmitted to the cylindrical wall portion W is separated from the sliding contact region of the second convex portion 2.

  In addition, the circumferential direction length of the groove part 9 does not necessarily need to be longer than the circumferential direction length of the sliding contact area of the second convex part 2. If a region where the groove portion 9 and the sliding contact region overlap with each other along the radial direction of the rotation axis X is formed, an effect of preventing the deformation of the pulley P from being transmitted to the cylindrical wall portion W can be obtained.

  In addition, by forming such a groove portion 9, even when the temperature of the drive-side rotator A is increased during operation of the internal combustion engine, the heat is hardly transmitted to the pulley P. Therefore, thermal deterioration of the drive belt V can be prevented. In the first place, by providing the groove portion 9, the amount of aluminum material used can be reduced, and the driving side rotating body A can be reduced in weight.

  On the other hand, the width 9a of the groove 9 along the radial direction can be configured in various sizes. Basically, the groove portion 9 is provided, and the cylindrical wall portion W and the pulley P are separated in the radial direction, so that the deformation of the pulley P is hardly transmitted to the cylindrical wall portion W. However, it is convenient to form the width 9a of the groove portion 9 to be equal to or greater than the width W3 of the contact surface W2 of the housing H.

  The housing H having this configuration is manufactured by extrusion molding of an aluminum material. Therefore, by setting the width 9a of the groove portion 9 to be equal to or greater than the width W3 of the contact surface W2, the pulley P is positioned radially outward from the outer surface of the cylindrical wall portion W to form the pulley P with a predetermined outer diameter. In addition, the extrusion amount of the aluminum material can be reduced by the amount of the groove portion 9. At this time, if the width 9a of the groove portion 9 is extremely narrow, the portion corresponding to the groove portion 9 becomes too thin when the extrusion mold is manufactured, and it becomes difficult to mold, and the mold life is shortened. However, by configuring the width 9a of the groove 9 to be equal to or greater than the width W3 of the contact surface W2, the dimensions of each part of the extrusion mold become appropriate, and an extrusion mold that is easy to manufacture and durable can be obtained. . If the width 9a of the groove 9 is appropriate, the extrusion resistance at the time of extrusion molding of the aluminum material is reduced, and the production efficiency is improved.

  Further, by setting the width 9a of the groove 9 to be equal to or greater than the width W3 of the contact surface W2, for example, when the front plate FP is bolted to the cylindrical wall W, the fastening force applied to the cylindrical wall W is connected. Propagation to the pulley P beyond the portion 6 can be prevented. Therefore, the shape of the pulley P is held in a perfect circle, rotation blur does not occur, and the drive belt V can be prevented from being damaged.

[Another embodiment]
Not only the housing H but also the front plate FP and the rear plate RP can be made of an aluminum material.

  If it is this structure, the weight of the drive side rotary body A will be reduced significantly. However, the female screw portion 8 for fixing the fastening bolt 5 in the rear plate RP is configured to have a necessary length along the longitudinal direction of the fastening bolt 5 so as to withstand a sufficient fastening torque.

  As a gap provided between the cylindrical wall portion W and the front plate FP or the rear plate RP, a concave portion extending in the radial direction with respect to the cylindrical wall portion W, the front plate FP, or the rear plate RP is configured. Also good. The concave portion is formed by, for example, cutting, molding, or stamping. With these processes, the oil outflow position and the outflow amount can be arbitrarily set, and a more accurate lubricating action can be achieved.

  INDUSTRIAL APPLICABILITY The present invention can be widely used for various valve opening / closing timing control devices that perform phase control by supplying and discharging working fluid.

1 1st convex part (partition part)
2 Second convex part (partition part)
9 Groove A Driving side rotating body B Driven side rotating body C Camshaft FP Front plate FP1 Front plate contact surface RP Rear plate RP1 Rear plate contact surface H Housing P Pulley R Fluid pressure chamber R1 Lead angle chamber R2 Delay angle Chamber V Drive belt W Cylindrical wall W1 Inner circumferential surface W2 Housing contact surface X Rotating shaft core Z Crankshaft

Claims (5)

A drive-side rotating body that rotates around the axis of rotation while rotating synchronously with the crankshaft of the internal combustion engine;
A driven-side rotating body that rotates integrally with the camshaft of the internal combustion engine around the rotating shaft core and is rotatable relative to the driving-side rotating body inside the driving-side rotating body;
A fluid pressure chamber formed by the driving side rotating body and the driven side rotating body;
The fluid pressure chamber is disposed in the fluid pressure chamber, and the fluid pressure chamber is divided into a retard angle chamber and an advance angle chamber that allow inflow or discharge of fluid, and the relative rotation phase of the driven side rotating body with respect to the driving side rotating body is determined as the inflow of fluid. A partition portion that selectively moves between a retarding direction in which the volume in the retarding chamber increases and an advance direction in which the volume in the advanced chamber increases due to the inflow of fluid,
The drive-side rotator has an aluminum housing provided with a pulley to which a driving force from the crankshaft is input via a drive belt, and at least one surface of the housing along the rotation axis. With attached plates,
A valve opening / closing timing control device in which a gap through which fluid can flow out is provided between the housing and the plate.   The valve timing control apparatus according to claim 1, wherein the pulley is anodized.   The at least one of the contact surfaces of the housing or the plate is an anodized surface having a predetermined surface roughness, and the contact surfaces of the housing and the plate are in direct contact with each other. 2. The valve opening / closing timing control device according to 2. The partition portion is provided on the driven-side rotating body, and the housing has a cylindrical wall portion having an inner peripheral surface with a sliding contact region that is in sliding contact with the partition portion,
Between the pulley and the cylindrical wall portion, a groove portion penetrating in the direction of the rotation axis and extending in a circumferential direction with respect to the rotation axis is formed,
4. The valve opening / closing timing control device according to claim 1, wherein the groove portion and the sliding contact region are configured to have an overlapping region along a radial direction of the rotation axis. 5.   The valve opening / closing timing control device according to claim 4, wherein a width of the groove portion along the radial direction of the rotating shaft core is formed to be equal to or greater than a width of the contact surface of the housing along the radial direction.

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