CN108266246A - A kind of adjustment mechanism for IC engine camshaft - Google Patents

Abstract

The invention discloses a kind of adjustment mechanisms for IC engine camshaft, including camshaft, cam sleeve and solenoid valve, guide hump portion is provided on the cam sleeve, the spool of the solenoid valve coordinates with guide hump portion, it is moved for driving cam sleeve along camshaft axial reciprocating, the spool is connected equipped with automatic resetting device, and after solenoid valve power-off, the spool returns to initial position under automatic resetting device effect.The guiding groove that the present invention is moved axially by the drive cam sleeve set on cam sleeve, the guiding groove does not need to setting spool and ejects slot, valve core of the electromagnetic valve under automatic resetting device effect after guiding groove by that can return to initial position, pass through the cooperation of cam guidance slot and solenoid valve, the position adjustment of camshaft is realized, so as to change valve stroke.The configuration of the present invention is simple, good reliability are of low cost.

Description

An adjustment mechanism for internal combustion engine camshaft

technical field

The invention belongs to the technical field of auto parts, in particular to an adjustment mechanism for a camshaft used for a variable valve lift of an internal combustion engine.

Background technique

With the development of the automobile industry and the shortage of oil resources, the rising oil price and the introduction of increasingly stringent environmental protection standards, it is more urgent to improve the engine's fuel consumption and environmental protection performance. Various automobile manufacturers have turned their attention to the variable valve lift technology to improve engine performance, and the current mainstream variable valve lift technology uses the cam shift method, but the current cam shift method, the cam sleeve is a whole Type spiral groove structure, and the radius of the spiral groove on the circumference is inconsistent, and the spiral groove is provided with a slope to push back the solenoid valve core. The solenoid valve does not have the function of automatic retraction after the cam is switched in place. This structure will accelerate the wear of the valve core. Moreover, the machining of the camshaft is difficult, and the size is not easy to guarantee, which will greatly increase the manufacturing cost of the camshaft sleeve.

Contents of the invention

The object of the present invention is to solve the problems mentioned above, to provide a camshaft adjustment mechanism for internal combustion engine with simple structure, high reliability, low manufacturing cost, and no spool ejection structure on the cam sleeve.

The technical solution of the present invention is achieved in the following way: an adjustment mechanism for a camshaft of an internal combustion engine, comprising a camshaft, a cam sleeve and a solenoid valve, characterized in that: a guide protrusion is provided on the cam sleeve, The spool of the solenoid valve cooperates with the guide protrusion to drive the cam sleeve to reciprocate along the axial direction of the camshaft. The spool is connected with an automatic return device. After the solenoid valve is powered off, the valve The core returns to the original position under the action of the automatic return device.

According to the adjustment mechanism for the internal combustion engine camshaft according to the present invention, the spool A and the spool B of the solenoid valve respectively cooperate with the side guide groove surface A and the guide groove surface B of the guide protrusion, and the valve The spool A and the spool B are respectively connected with the spool return mechanism A and the spool return mechanism B.

In the adjustment mechanism for internal combustion engine camshaft according to the present invention, the cam sleeve is an integral structure, and the high cam and low cam on the cam sleeve move axially with the cam sleeve as a whole, and when they are in place, Finally, the axial limit is carried out by the limit mechanism.

According to the adjustment mechanism for the internal combustion engine camshaft according to the present invention, the cam sleeve is a combined structure, including a high cam, a low cam, a sleeve and a guide protrusion, and the high cam, the low cam and the guide protrusion The lifting part is fixed on the sleeve by riveting or interference press-fitting, and moves axially with the guiding raised part as a whole, and is axially limited by the limiting mechanism after moving in place.

According to the adjustment mechanism for the internal combustion engine camshaft according to the present invention, the cam sleeve is a split structure, including the sleeve in the middle, the high and low cam groups arranged at both ends of the sleeve, and the guides located at both ends of the cam sleeve. Protruding parts, the guiding protruding parts respectively cooperate with the spools of the corresponding electromagnetic valves, and the parts in the cam sleeve of the split structure are relatively abutted against, and the whole moves axially along the camshaft under the action of the electromagnetic valve, And after moving in place, the guide protrusions at both ends of the cam sleeve are axially limited by corresponding limiting mechanisms respectively.

In the adjusting mechanism for the camshaft of an internal combustion engine according to the present invention, the camshaft and the cam sleeve are matched in a polygonal manner, and the number of sides where the camshaft and the cam sleeve cooperate is an integer multiple of the number of corresponding engine cylinders.

The present invention guides the cam sleeve to move axially through the guide groove provided on the cam sleeve. The guide groove does not need to be provided with a valve core ejection groove. In the initial position, through the cooperation of the cam guide groove and the solenoid valve, the position adjustment of the camshaft is realized, thereby changing the valve lift. The invention has simple structure, good reliability and low cost.

Description of drawings

Fig. 1 is a schematic structural diagram of Embodiment 1 of the present invention.

Fig. 2 is a structural schematic diagram of the coordination between the solenoid valve core and the guide groove in Embodiment 1 of the present invention.

Fig. 3 is a schematic structural view of a cam sleeve in Embodiment 1 of the present invention.

Fig. 4 is a cross-sectional view of the integral cam sleeve in Embodiment 1 of the present invention.

Fig. 5 is a cross-sectional view of the combined cam sleeve in Embodiment 1 of the present invention.

Fig. 6 is a schematic structural view of a cam sleeve in Embodiment 2 of the present invention.

Fig. 7 is a sectional view of a cam sleeve in Embodiment 2 of the present invention.

Fig. 8 is a structural schematic diagram of the mating surface of the cam sleeve in the present invention.

Fig. 9 is a structural schematic diagram of the cam mating surface in the present invention.

Reference numerals: 1 is a camshaft, 2 is a cam sleeve, 3 is a solenoid valve, 4 is a high cam, 5 is a low cam, 6 is a sleeve, 7 is a guide protrusion, 7a is a guide groove surface A, 7b 8a is the first groove A of the limiter, 8b is the first groove B of the limiter, 9a is the second groove A of the limiter, 9b is the second groove B of the limiter, and 10 is the sleeve 11 is the cam matching surface, 12a is the spool A, 12b is the spool B, 13a is the spool return mechanism A, and 13b is the spool return mechanism B.

Detailed ways

Below in conjunction with accompanying drawing, the present invention is described in detail.

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

Embodiment 1: As shown in Figures 1-4, an adjustment mechanism for a camshaft of an internal combustion engine includes a camshaft 1, a cam sleeve 2 and a solenoid valve 3, and guide protrusions are provided on the cam sleeve 2 Part 7, the valve core of the solenoid valve 3 cooperates with the guide protrusion 7 to drive the cam sleeve 2 to reciprocate along the axial direction of the camshaft 1, and the valve core is connected with an automatic return device, when the solenoid valve When the spool extends into the guide groove of the cam sleeve, under the action of the rotation of the camshaft, the cam sleeve moves along the axial direction of the camshaft to adjust the position of the cam and realize switching of the valve lift. When the spool passes through the guide groove, The cam sleeve and the camshaft are fixed by the limit device, the solenoid valve 3 is powered off, and the valve core returns to the initial position under the action of the automatic return device, and there is no need to set an ejection groove on the cam sleeve. The guide groove unit The radius is set to the same radius value and has the same base circle, and the automatic return device can be spring, electromagnet attraction, permanent magnet attraction and other return methods.

In this embodiment, the spool A12a and the spool B12b of the electromagnetic valve 3 correspond to the side guide groove surface A7a and the guide groove surface B7b of the guide protrusion 7 respectively, and the guide groove may be a spiral groove or a spiral groove. It can be inclined, and the valve core A12a and valve core B12b are respectively connected with the valve core return mechanism A13a and the valve core return mechanism B13b; the cam sleeve 2 is an integral structure, and the cam sleeve 2 The high cam 4 and the low cam 5 move axially along with the cam sleeve 2 as a whole, and are axially limited by a limit mechanism after moving in place.

As shown in Figure 5, as another structure, the cam sleeve 2 is a combined structure, including a high cam 4, a low cam 5, a sleeve 6 and a guide protrusion 7, and the high cam 4, low cam 5 and the guide protrusion 7 are fixed on the sleeve 6 by riveting or interference press fitting or other methods, and move axially with the guide protrusion 7 as a whole, and after moving in place, the axial limit is performed by the limit mechanism. bit.

The working principle of the present invention is: the spool A of the solenoid valve is extended when the solenoid valve is energized, and the cam sleeve guides the groove surface A to contact the spool A under the rotation of the camshaft. Axial slip occurs. When the guide groove surface A passes through the valve core A, the camshaft enters the first groove A of the limit device from the first groove B of the limit device to limit the position. The switching between the low cam and the high cam is completed, and the solenoid valve is off. Electricity, the spool A returns to the initial position under the action of the spool return mechanism A, and the adjustment of the cam position is completed. Similarly, when the solenoid valve is energized, the spool B is stretched out, and the position of the camshaft is reversely adjusted.

Embodiment 2: As shown in Figures 6 and 7, the cam sleeve 2 is a split structure, including the sleeve 6 in the middle, the high and low cam groups arranged at both ends of the sleeve 6 and the cam sleeves located at both ends of the cam sleeve 2. Guide protrusions 7, the guide protrusions 7 respectively cooperate with the spools of the corresponding solenoid valves, and the parts in the split-type cam sleeve 2 are relatively abutted against, and the entire camshaft is moved along the camshaft under the action of the solenoid valve. 1 moves in the axial direction, and after the movement is in place, the guide protrusions 7 at both ends of the cam sleeve 2 are axially limited by corresponding limiting mechanisms.

The working principle of the present invention is: the spool A of the solenoid valve is extended when the solenoid valve is energized, and the cam sleeve guides the groove surface A to contact the spool A under the rotation of the camshaft. Axial slip occurs. When the guide groove surface A passes through the valve core A, the first groove B of the camshaft limiter enters the first groove A of the limiter, and the second groove B of the camshaft limiter enters the first groove B of the limiter. The second slot A is limited, the high cam and low cam switch is completed, the solenoid valve is powered off, the valve core A automatically returns to the initial position under the action of the valve core return mechanism A, and the cam position adjustment is completed. Similarly, when the solenoid valve is energized, the spool B is stretched out, and the position of the camshaft is reversely adjusted.

As shown in Figures 8 and 9, the camshaft 1 and the cam sleeve 2 are matched in a polygonal manner; A cam mating surface 11 is provided, and the number of sides that the camshaft 1 cooperates with the cam sleeve 2 is an integer multiple of the number of corresponding engine cylinders, such as the number of sides that the camshaft and the cam sleeve of a three-cylinder machine cooperate with can be 3, 6, 9 , 12, etc.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. within range.

Claims (6)

1. a kind of adjustment mechanism for IC engine camshaft, including camshaft（1）, cam sleeve（2）And solenoid valve（3）, It is characterized in that：In the cam sleeve（2）On be provided with guide hump portion（7）, the solenoid valve（3）Spool and guiding it is convex The portion of rising（7）Cooperation, for driving cam sleeve（2）Along camshaft（1）Axial reciprocating moves, and the spool is filled equipped with self-return It puts, in solenoid valve（3）After power-off, the spool returns to initial position under automatic resetting device effect.

2. the adjustment mechanism according to claim 1 for IC engine camshaft, it is characterised in that：The solenoid valve（3） Spool A（12a）With spool B（12b）Respectively with guide hump portion（7）Side guiding groove face A（7a）With guiding groove face B（7b） Corresponding matching, the spool A（12a）With spool B（12b）Respectively with spool return mechanism A（13a）With spool return mechanism B （13b）Connection.

3. the adjustment mechanism according to claim 2 for IC engine camshaft, it is characterised in that：The cam sleeve （2）For monolithic construction, the cam sleeve（2）On high cam（4）With low cam（5）With cam sleeve（2）It is whole axial It is mobile, and axial limiting is carried out by position-limit mechanism afterwards in place in movement.

4. the adjustment mechanism according to claim 2 for IC engine camshaft, it is characterised in that：The cam sleeve （2）For fabricated structure, including high cam（4）, low cam（5）, sleeve（6）With guide hump portion（7）, the high cam（4）、 Low cam（5）With guide hump portion（7）Sleeve is fixed on by way of riveting or interference press fitting（6）On, and it is convex with guiding The portion of rising（7）Whole axial movement, and axial limiting is carried out by position-limit mechanism afterwards in place in movement.

5. the adjustment mechanism according to claim 2 for IC engine camshaft, it is characterised in that：The cam sleeve （2）For split structure, the sleeve including middle part（6）, be arranged on sleeve（6）The height cam set at both ends and positioned at cam Sleeve（2）The guide hump portion at both ends（7）, the guide hump portion（7）Coordinate respectively with the spool of corresponding solenoid valve, described point The cam sleeve of body formula structure（2）In each component it is opposite against and integrally along camshaft under electromagnetism valve action（1）It is axial to move It is dynamic, and after movement in place, the cam sleeve（2）The guide hump portion at both ends（7）Respectively by corresponding position-limit mechanism into Row axial limiting.

6. the adjustment mechanism as claimed in any of claims 1 to 5 for IC engine camshaft, it is characterised in that： The camshaft（1）With cam sleeve（2）Coordinated using polygon mode, the camshaft（1）With cam sleeve（2）Match The number of edges of conjunction is the integral multiple of corresponding engine cylinder number.