JP2008038722A - Method for assembling variable valve gear - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To secure good work efficiency in an assembly process of a variable valve gear by preventing a lost lifter or the like from falling off of a lost stay in a process installing a lost motion mechanism on the variable valve gear. <P>SOLUTION: In a method for assembling the variable valve gear provided with a support shaft 8 different from a camshaft 6, an intervention drive mechanism rockably supported by the support shaft, a mediation phase difference variable means capable of varying relative phase difference between output parts 24, 26 and an input part 22 of the mediation drive mechanism, and the lost motion mechanism 50 energizing the mediation drive mechanism to a projection part 22g provided on an outer circumference surface of the mediation drive mechanism from an upper part, the lost lifter is inserted from an upper end of a through hole in an order of the lost lifter and a spring 53 in such a manner that the lost lifter abuts on the projection part from an upper part after installing the lost stay 51 including a through hole 51a of which circumference surface the lost lifter 52 contacts and slides on above the projection part, and an upper end of the spring is engaged with the circumference surface of the through hole and is locked by a retainer ring 54 or a cap. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for assembling a variable valve mechanism that controls valve characteristics in accordance with the operating state of an internal combustion engine.

Conventionally, as described in Patent Document 1 shown in FIG. 6, the shaft 108 is swingably supported by a shaft 108 different from the camshaft 106, and the relative phase difference between the input unit 122 and the output units 124 and 126 is determined as the input unit and the output unit. There has been proposed a variable valve mechanism having an intermediary drive mechanism that is variable by a displacement in the axial direction of a spline provided inside the slider and a slider gear meshing with the spline. Further, as described in Patent Document 2, in order to prevent the input unit 122 from moving away from the cam 106a, the lost motion mechanism 150 that urges the input unit 122 to swing in a direction opposite to the swinging direction by the cam is provided. A variable valve mechanism has been proposed.
JP 2001-263015 A JP 2006-97602 A

  However, the variable valve mechanism including the lost motion mechanism 150 is structurally configured so that the loss trilifter 152 contacts the projection 122g of the input unit from above and biases the input unit 122, so that the loss trilifter 152 is directed downward. A lost motion mechanism 150 is provided. Accordingly, when the lost motion mechanism 150 is assembled, the loss lifter 152 faces downward, so that the lost motion mechanism 150 changes from the state shown in FIG. 7A to the state shown in FIGS. 7B and 7C ( It is assembled in the state shown in d). However, during the assembly process, as shown in FIG. 7 (e), the loss trifter 152 and the lost spring 153 are detached from the lost stay 151 and dropped, and the workability of the assembly process is deteriorated.

  Accordingly, it is an object of the present invention to provide a method for assembling a variable valve mechanism that has good workability by preventing the loss lifter or the lost spring from falling off the lost stay in the process of assembling the lost motion mechanism to the variable valve mechanism. .

  In order to achieve the above object, the present invention has a support shaft that is different from a camshaft and is swingably supported by the support shaft, and has an input portion and an output portion so that the input portion is driven by the rotating cam. Then, the intermediate drive mechanism for driving the valve at the output unit, and the relative phase difference between the input unit and the output unit of the intermediate drive mechanism mesh with the spline and the spline provided inside the input unit and the output unit. An intermediate phase difference variable means that is variable by the displacement of the slider gear in the axial direction, and a lost that energizes the intermediate drive mechanism when a loss trifter comes into contact with a protrusion provided on the outer peripheral surface of the intermediate drive mechanism from above. A variable valve mechanism assembly method including a motion mechanism.

  In the assembling method of the variable valve mechanism according to the present invention, after the lost stay having a through hole on which the loss trilifter comes into contact with and slides on the peripheral surface above the projection, the loss trilifter contacts the projection from above. The loss lifter and the spring are inserted in this order from the upper end of the through hole so that they come into contact with each other, and then the upper end of the spring is locked.

  Examples of the method of locking the upper end of the spring include a method of using a retaining ring and a method of using a stopper that engage with the peripheral surface of the through hole. In the present specification, “upward” includes not only directly above but also obliquely upward.

  According to the assembling method of the variable valve mechanism of the present invention, it is possible to provide a method with good workability by preventing the loss lifter or the lost spring from falling off the lost stay in the process of assembling the lost motion mechanism to the variable valve mechanism. can do.

  The present invention has a support shaft different from the camshaft, and is supported by the support shaft so as to be swingable, and has an input portion and an output portion so that when the input portion is driven by the rotating cam, a valve is provided at the output portion. An intermediate drive mechanism for driving the intermediate drive mechanism, and a relative phase difference between the input section and the output section of the intermediate drive mechanism in the axial direction of the spline provided in the input section and the output section and the slider gear that meshes with the spline. Variable motion comprising: a mediation phase difference varying means that is variable by displacement; and a lost motion mechanism that biases the mediation drive mechanism by contacting a loss lifter from above to a protrusion provided on the outer peripheral surface of the mediation drive mechanism. It is an assembly method of a valve mechanism.

  In the assembling method of the variable valve mechanism according to the present invention, after the lost stay having a through hole on which the loss trilifter comes into contact with and slides on the peripheral surface above the projection, the loss trilifter contacts the projection from above. It is characterized by inserting the upper end of the through hole in the order of the loss trilifter and the spring so as to come into contact with each other, and then locking the upper end of the spring with a retaining ring or a stopper that engages with the peripheral surface of the through hole. .

  As shown in FIGS. 1 to 4, the variable valve mechanism used in the present embodiment is a variable valve mechanism of an internal combustion engine having a plurality of cylinders arranged in parallel. This variable valve mechanism opens and closes a camshaft 6 that is rotated by a crankshaft (not shown) of an engine, a plurality of rotating cams 6a fixed on the camshaft 6, and a valve 2 below the camshaft 6. A rocker arm 4 that supports a roller 4a at an intermediate portion and is supported by a pivot 4b on the base end side so as to swing up and down, a support shaft 8 provided in parallel with the camshaft 6, and a plurality of shafts supported by the support shaft 8. The mediation drive mechanism 20, the mediation phase difference varying means 10 for continuously adjusting the phase difference between the input section 22 of the mediation drive mechanism 20 and the swing cams 24, 26, and the mediation drive mechanism 20 is swung by the rotating cam 6a. It comprises a lost motion mechanism 50 that urges it to swing in a direction opposite to the direction.

  The intermediate phase difference varying means 10 is provided on the inner peripheral surface of the input portion 22 and on the inner peripheral surfaces of the swing cams 24 and 26, and the output portion having an angle different from that of the input spline 22b. The splines 24b and 26b and the shaft body 12 that is movable in the axial direction of the mediation drive mechanism 20 include an input spline 14a that meshes with the input spline 22b and output splines 14c and 14e that mesh with the output splines 24b and 26b. The slider gear 14 that is provided on the outer peripheral surface of the shaft body 12 and relatively rocks the input portion 22 and the rocking cams 24 and 26 in accordance with the movement in the axial direction by meshing them, and the axial direction of the slider gear 14 And a lift amount variable actuator (not shown) for adjusting the displacement.

  Further, the support shaft 8 is divided into a plurality of shaft bodies 12 corresponding to the number of cylinders, the shaft bodies 12 are butted against each other and supported so that they can be displaced in the axial direction and can be rotated independently. The shaft body 12 is used as the shaft body 12 of the slider gear 14, and the input spline 14 a and the output splines 14 c and 14 e are formed on each shaft body 12 to form the slider gear 14.

  The intermediary drive mechanism 20 includes an input portion 22 provided in the center, a first swing cam 24 provided on the left, and a second swing cam 26 provided on the right. The housing 22a of the input portion 22 and the housings 24a and 26a of the swing cams 24 and 26 have a cylindrical shape with the same outer diameter, and the intermediate phase difference varying means 10 is provided in each housing. .

  From the outer peripheral surfaces of the housings 24a and 26a of the first and second swing cams 24 and 26, substantially triangular noses 24d and 26d are formed so as to protrude. One side of these noses 24d and 26d forms cam surfaces 24e and 26e that are curved in a concave shape.

  Two arms 22c and 22d are formed to protrude in parallel from the outer peripheral surface of the input portion. A shaft 22e is stretched between the arms 22c and 22d at the tips of the arms 22c and 22d. The shaft 22e is parallel to the axial direction of the housing 22a, and an input roller 22f is rotatably attached thereto.

  Further, a flange-like protrusion 22g is provided on the outer peripheral surface of the input portion 22 that is substantially opposite to the arm 22c, 22d formed on the outer peripheral surface of the housing 22a and the axis of the housing 22a. A lost motion mechanism 50 is provided so that the loss lifter 52 comes into contact with the vicinity of the tip of the plate from above.

  As shown in FIGS. 1 and 4, the lost motion mechanism 50 abuts the input portion 22 by contacting the protruding portion 22g with the lost stay 51 having a through hole 51a in which the loss lifter 52 contacts and slides on the peripheral surface 51d. It comprises a losing trifter 52 that is biased, a lost spring 53 that generates a biasing force of the lost motion mechanism 50 by contracting, and a C-type retaining ring 54 that prevents the lost spring 53 from extending upward. Yes.

  In the lost stay 51, a hooking groove 51b is formed in the vicinity of the upper end of the peripheral surface 51d of the through hole 51a along the circumferential direction, and a base portion 51c bent at the center in the longitudinal direction is formed at the lower end of the through hole 51a. . The loss lifter 52 has a cylindrical shape with a closed lower end, and an outer peripheral surface is in sliding contact with the peripheral surface 51d. The C-type retaining ring 54 is fitted in the hooking groove 51b.

  As shown in FIG. 4, the method of assembling the lost motion mechanism 50 to the variable valve mechanism of this embodiment is as follows. (A) First, a lost stay 51 is installed above the protrusion 22g. (B) Then, the loss trifter 52 is inserted from the upper end of the through hole 51a of the lost stay 51 so that the lower end surface 52a abuts against the protrusion 22g. (C) Thereafter, the lost spring 53 is inserted from the upper end of the through hole 51a. (D) Further, while pressing the upper end of the lost spring 53 with the C-type retaining ring 54, (e) the C-type retaining ring 54 is fitted into the catching groove 51b.

  According to the present embodiment, it is possible to prevent the loss lifter 52 and the lost spring 53 from falling off the lost stay 51 in the process of assembling the lost motion mechanism 50 to the variable valve mechanism, and to improve the workability of the process.

  As shown in FIG. 5, the variable valve mechanism used in the present embodiment is different from the first embodiment in the aspect of the lost motion mechanism 50. In the lost motion mechanism 50 of this embodiment, the input portion 22 is urged by abutting from above the lost stay 55 having a through hole 55a in which the loss lifter 52 contacts and slides on the peripheral surface 55d and the protruding portion 22g. It comprises a lost spring 53 and a lost spring 53 that generates an urging force of the lost motion mechanism 50 by contracting, and a screw plug 56 that prevents the lost spring 53 from extending upward.

  In the lost stay 55, a female screw 55b is formed on the intermediate portion from the upper end of the peripheral surface 55d of the through hole 55a, and a base portion 55c bent at the center in the longitudinal direction is formed at the lower end of the through hole 55a. The loss lifter 52 has a cylindrical shape with a closed lower end, and an outer peripheral surface is in sliding contact with the peripheral surface 55d. The screw plug 56 has a cylindrical shape with a closed upper end, and a male screw 56a that engages with a female screw 55b provided on the peripheral surface 55d is provided on the outer periphery, and the outer peripheral upper end 56b contacts the upper end surface 55e of the lost stay 55. The diameter is expanded.

  As shown in FIG. 5, the method of assembling the lost motion mechanism 50 to the variable valve mechanism of this embodiment is as follows. (A) First, a lost stay 55 is installed above the protrusion 22g. (B) Then, the loss trifter 52 is inserted from the upper end of the through hole 55a of the lost stay 55 so that the lower end surface 52a abuts against the protrusion 22g. (C) Thereafter, the lost spring 53 is inserted from the upper end of the through hole 55a. (D) Further, while pressing the upper end of the lost spring 53 against the inner surface of the upper end of the screw plug 56, (e) screwing the screw plug 56 into the through hole 55a until the outer peripheral upper end 56b contacts the upper end surface 55e of the lost stay 55. .

  According to the present embodiment, it is possible to prevent the loss lifter 52 and the lost spring 53 from being detached from the lost stay 55 in the process of assembling the lost motion mechanism 50 to the variable valve mechanism, thereby improving the workability of the process.

It is sectional drawing of the variable valve mechanism of Example 1. FIG. It is a perspective view of the mechanism. It is a perspective view which shows the mechanism partially broken and shows. It is a schematic diagram of the process of assembling a lost motion mechanism to the same mechanism. It is a schematic diagram of the process of assembling a lost motion mechanism to the variable valve mechanism of Example 2. It is sectional drawing of the conventional variable valve mechanism. It is a schematic diagram of the process of assembling a lost motion mechanism to the same mechanism.

Explanation of symbols

2 Valve 6 Camshaft 6a Rotating Cam 8 Support Shaft 10 Mediating Phase Difference Variable Means 12 Shaft Body 14 Slider Gear 14a Input Spline 14c Output Spline 14e Output Spline 20 Mediation Drive Mechanism 22 Input Portion 22b Input Portion Spline 22g Protrusion Portion 24 First swing cam 24b Output section spline 26 Second swing cam 26b Output section spline 50 Lost motion mechanism 51 Lost stay 51a Through hole 52 Loss trifter 53 Lost spring 54 Retaining ring 55 Lost stay 55a Through hole 56 Screw plug

Claims (1)

A support shaft that is different from the camshaft, and is supported by the support shaft so as to be swingable. By having an input portion and an output portion, when the input portion is driven by the rotating cam, the output portion drives the valve. The relative phase difference between the input mechanism and the output section of the drive mechanism and the intermediate drive mechanism can be varied by the displacement in the axial direction of the input section and the spline provided inside the output section and the slider gear meshing with the spline. Assembling the variable valve mechanism comprising: a mediating phase difference varying means that performs a lost motion mechanism that urges the mediating drive mechanism when a loss lifter abuts against a protrusion provided on an outer peripheral surface of the mediating drive mechanism from above In the method
After installing a lost stay having a through hole in contact with and sliding on the circumferential surface of the loss trilift above the protrusion, the loss trilifter and spring are passed through in order so that the loss trilift comes into contact with the protrusion from above. A method for assembling the variable valve mechanism, wherein the variable valve mechanism is inserted from the upper end of the hole and then the upper end of the spring is locked.

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