VARIABLE VALVE APPARATUS

Abstract

A variable valve apparatus includes a swing arm that includes a first body that pivots in response to rotation of an input cam, and a second body hingedly connected to the first body at a first connection. A connecting portion connects and disconnects the bodies at a second connection, in response to hydraulic pressure supplied thereto. When hydraulic pressure is not supplied to the connecting portion, the second body is connected to the first body and pivots along with the first body to open a valve.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to, and the benefit of, Korean Patent Application No. 10-2007-0130415 filed in the Korean Intellectual Property Office on Dec. 13, 2007, the entire contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

(a) Field of the Invention

The present invention relates to a variable valve apparatus.

(b) Description of the Related Art

A typical combustion chamber of an automotive engine is provided with an intake valve for supplying an air/fuel mixture and an exhaust valve for expelling burned gas. The intake and exhaust valves are opened and closed by a valve lift apparatus connected to a crankshaft.

A cylinder deactivation (CDA) apparatus deactivates some of the intake/exhaust valves under certain conditions. A conventional cylinder deactivation apparatus uses a double cam and a variable tappet, which are complicated to manufacture and expensive.

The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.

SUMMARY OF THE INVENTION

A variable valve apparatus includes a swing arm that includes a first body that pivots in response to rotation of an input cam, and a second body hingedly connected to the first body at a first connection. A connecting portion connects and disconnects the bodies at a second connection, in response to hydraulic pressure supplied thereto. When hydraulic pressure is not supplied to the connecting portion, the second body is connected to the first body and pivots along with the first body to open a valve.

The first connection may include a connecting pin connecting the first body with the second body, and a stopper that prevents the second body from tilting more than a certain amount with respect to the first body. The connecting portion may include a connecting pin selectively connecting the bodies, and a return spring supplying restoring force to the connecting pin.

The apparatus may further include a hydraulic pressure supplying portion that supplies the hydraulic pressure to the connecting portion. The hydraulic pressure supplying portion may include a hydraulic lash adjuster supporting the swing arm, and a hydraulic line disposed at the first body. The hydraulic line may fluidly connect a first hole in the first body, for receiving hydraulic pressure from the hydraulic lash adjuster, to a second hole in the first body, for supplying hydraulic pressure to the second connecting unit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a swing arm of a variable valve apparatus according to an exemplary embodiment in a general mode.

FIG. 2 is an enlarged view of area A in FIG. 1.

FIG. 3 shows the swing arm of FIG. 1 in a CDA mode.

FIG. 4 is a perspective view of a connecting portion of a variable valve apparatus according to an exemplary embodiment in a general mode.

FIG. 5 shows the connecting portion of FIG. 4 in CDA mode.

FIG. 6 is a side view showing operation of a variable valve apparatus according to an exemplary embodiment in a general mode.

FIG. 7 is a side view showing an operation of the apparatus of FIG. 6 in CDA mode.

FIG. 8 is a perspective view of a hydraulic pressure supplying portion of a variable valve apparatus according to an exemplary embodiment.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

An exemplary embodiment of the present invention will hereinafter be described in detail with reference to the accompanying drawings.

Referring to FIGS. 1-3 and 6-8, a variable valve apparatus according to an exemplary embodiment includes an input cam 100 (FIG. 7) and a swing arm 200 that is disposed below the input cam 100 for contacting the input cam 100. The swing arm 200 includes a first body 210 and a second body 220 for opening a valve 600 as shown in FIG. 6.

A connecting portion 300, as shown in FIG. 5, selectively connects the first body 210 and the second body 220, and a hydraulic pressure supplying portion 500, 410 (described in detail below) supplies hydraulic pressure to the connecting portion 300.

The connecting portion 300 includes a first connecting unit 310 constantly connecting the first body 210 and the second body 220, and a second connecting unit 320 receiving hydraulic pressure from the hydraulic pressure supplying portion and selectively connecting the first body 210 with the second body 220.

The first connecting unit 310 includes a first connecting pin 311 connecting the first body 210 with the second body 220 and a stopper 312 preventing the second body 220 from pivoting with respect to the first body 210 more than a set angle.

The second connecting unit 320 includes a second connecting pin 321 selectively connecting the first body 210 and the second body 220 according to receiving hydraulic pressure from the hydraulic pressure supplying portion, and a return spring 322 supplying restoring force to the second connecting pin 321.

The hydraulic pressure supplying portion includes a hydraulic lash adjuster 500 (FIGS. 6 and 7) supporting the swing arm 200, and a first body hydraulic line 410 (FIG. 8) on the first body 210.

The first body hydraulic line 410 includes a first hole 411 in a side of the first body 210 for receiving hydraulic pressure from the hydraulic lash adjuster 500, and a second hole 422 in the side of the first body 210 for supplying hydraulic pressure to the second connecting unit 320. The first body hydraulic line 410 wraps around the side of the first body 210 and connects the first hole 411 and the second hole 422.

Referring to FIG. 4 to FIG. 7, operation of the variable valve apparatus according to an exemplary embodiment of the present invention will be explained.

Hydraulic pressure is not supplied to the second connecting pin 321 in the general mode. Thus, as shown in FIG. 6, the variable valve is disposed within a cylinder head 700. The first body 210 and the second body 220 are connected by the second connecting pin 321, and the swing arm 200 operates in a conventional manner.

Hydraulic pressure is supplied to the second connecting pin 321 in the CDA mode. As shown in FIG. 7, the second connecting pin 321 is separated from the second body 220, and the second body 220 is disconnected from the first body 210. Rotation of the input cam 100 is not transmitted to the valve 600 so that the valve is not opened in the CDA mode. When the mode is changed from the CDA mode to the general mode, hydraulic pressure supplied to the second connecting pin 321 is released, and the second connecting pin 321 connects the first body 210 and the second body 220 by the return spring 322.

Then, a rotation of the input cam 100 pushes the swing arm 200, and the valve 600 is opened by the first body 210 and the second body 220.

While this invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. A variable valve apparatus comprising a swing arm, the swing arm comprising: a first body configured to pivot in response to a rotation of an input cam;a second body hingedly connected to the first body at a first connection; anda connecting portion configured to connect and disconnect the first body and the second body at a second connection in response to hydraulic pressure supplied thereto, such that when the hydraulic pressure is not supplied to the connecting portion, the second body is connected to the first body and pivots along with the first body to open a valve.

2. The variable valve apparatus of claim 1, wherein the first connection comprises: a connecting pin connecting the first body with the second body; anda stopper for preventing the second body from tilting more than a certain amount with respect to the first body.

3. The variable valve apparatus of claim 1, wherein the connecting portion comprises: a connecting pin selectively connecting the first body and the second body; anda return spring supplying restoring force to the connecting pin.

4. The variable valve apparatus of claim 1, further comprising a hydraulic pressure supplying portion that supplies the hydraulic pressure to the connecting portion, the hydraulic pressure supplying portion comprising a hydraulic lash adjuster supporting the swing arm, and a hydraulic line disposed at the first body.

5. The variable valve apparatus of claim 4, wherein the hydraulic line fluidly connects a first hole in the first body for receiving hydraulic pressure from the hydraulic lash adjuster to a second hole in the first body for supplying hydraulic pressure to the second connecting unit.