Shield drive device for head lamp

A shield drive device for a head lamp may include a shield deployed in front of a light source positioned in a lamp assembly to be opened and closed while rotating by using a hinge portion as an axis, an actuator connected to a shield arm through a shaft while being deployed below the shield to rotate the shield, a sliding contact member deployed to be close to the shield arm of the shield to provide friction contact force when the shield rotates, and a sliding stopper and a spring mounted on the shield arm of the shield and configured to decelerate and control a motion of the shield while being compressed or de-compressed while contacting the sliding contact member when the shield rotates.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority to Korean Patent Application No. 10-2014-0173603, filed Dec. 5, 2014, the entire contents of which is incorporated herein for all purposes by this reference.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a shield drive device for a head lamp, and more particularly, to a shield drive device that opens and closes a shield to drive a high beam and a low beam in a bi-functional head lamp.

Description of Related Art

In general, an illumination device is installed in a vehicle in order to stably secure a view of a driver when surrounding illumination is low while driving.

A head lamp in the illumination device is primarily used to secure a stable visual distance of the driver.

In general, the head lamp may selectively irradiate a high beam and a low beam forward according to an irradiation angle and a light amount of light irradiated from a light source and the selective irradiation of the high beam and the low beam is performed by opening and closing operations of a shield by driver's operating a switch or automatically performed by the opening and closing operations of the shield according to a driving state of the vehicle.

FIGS. 6 and 7are a side view, a perspective view, and a front view illustrating a shield drive device in the related art.

As illustrated inFIGS. 6 and 7, an actuator110that actuates a shield130is deployed below a lamp assembly100, the shield130which is foldable by a lower end hinge structure is deployed in front of a light source (not illustrated), and a plunger140of the actuator110is connected to a lower end portion of the shield130together with a damper150.

Herein, undescribed reference numerals160and170represent a shield spring providing force for automatic shield closing and a noise preventing damper, respectively.

Therefore, when the shield is maintained in a closed state, the low beam may be implemented (for example as shown in various embodiments of the present invention illustrated inFIG. 1) and when the shield is maintained in an opened state, the high beam may be implemented (for example as shown in various embodiments of the present invention illustrated inFIG. 2).

However, in the shield drive device in the related art, a plunger distortion phenomenon occurs due to generation of a height difference between the actuator and a shield connection unit when the shield is opened and closed, and as a result, there is a problem in that noise is generated when the shield is driven.

For example, as illustrated inFIG. 8, while the shield130is closed, centers of a plunger connection unit, the damper150, and the shield connection unit coincide with each other, distortion does not occur, but as illustrated inFIG. 9, when the shield130rotates while the actuator110is driven, the shield130rotates around a rotational shaft and in this case, a height difference H is generated between the plunger connection unit and the shield connection unit to cause the damper150to be twisted and the plunger to be distorted and consequently, such a phenomenon results in generation of the noise.

That is, when the shield is opened by driving the actuator, large noise is not generated, but while applied voltage of the actuator is cut off, when the shield is closed by spring restoration force, the large noise is generated while the noise preventing damper and the shield collide with each other.

BRIEF SUMMARY

Various aspects of the present invention are directed to providing a shield drive device of a head lamp that adopts a drive mechanism providing rotational power in the same direction as a rotational direction of a shield and implements a new type of shield driving scheme adopting a spring damper mechanism capable of a rapid motion of the shield through slide friction contact when the shield is opened and closed to significantly reduce generation of impact and noise when the shield is opened and closed and secure operational quality of the shield.

According to various aspects of the present invention, a shield drive device for a head lamp may include a shield deployed in front of a light source positioned in a lamp assembly to be opened and closed while rotating by using a hinge portion as an axis, an actuator connected to a shield arm through a shaft while being deployed below the shield to rotate the shield, a sliding contact member deployed to be close to the shield arm of the shield to provide friction contact force when the shield rotates, and a sliding stopper and a spring mounted on the shield arm of the shield and configured to decelerate and control a motion of the shield while being compressed or de-compressed while contacting the sliding contact member when the shield rotates.

The actuator may be deployed in line below the shield to provide rotational drive force in a same direction as a rotational direction of the shield.

A plurality of sliding stoppers and springs may be provided, at least one of which may be configured to decelerate and control a shield motion when the shield is opened and another of which is configured to decelerate and control the shield motion when the shield is closed.

An inclination surface having a height difference in a circumferential direction may be provided on a front surface of the sliding contact member, and as a result, a shield deceleration control may be achieved while the sliding stopper passes through an inclination surface section.

The inclination surface of the sliding contact member may comprise two inclination surfaces having a phase difference of 180° from each other and which are gradually heightened in opposite directions to each other based on the circumferential direction.

A shield drive device of a head lamp according to the present invention achieves the following effects.

First, a drive mechanism is applied, which sets a power transfer direction of an actuator and a drive direction of a shield to the same direction to completely exclude a plunger distortion problem in the related art and simply an overall structure.

Second, when the shield is opened and closed, a spring damper mechanism capable of controlling a rapid motion of the shield is applied to significantly reduce generation of noise when the shield is driven.

DETAILED DESCRIPTION

FIG. 1is a combinational perspective view illustrating a shield drive device according to various embodiments of the present invention.FIG. 2is an exploded perspective view illustrating the shield drive device according to various embodiments of the present invention.

As illustrated inFIGS. 1 and 2, the shield drive device is applied to a lamp assembly10including a light source12, and the like and is configured in a mechanism that prevents noise from being generated by appropriately controlling a shield motion when a shield13is opened and closed.

To this end, the shield drive device includes the shield13as a mechanism for implementing a high beam and a low beam and the shield13is installed in a rotatable structure by using a hinge portion15as an axis while being deployed in front of the light source12positioned in the lamp assembly10.

Herein, the hinge portion15of the shield13may be fastened and supported onto one side of a shield holder21by a pin22.

The shield13is driven by an actuator11to be described below and while the shield is bent forth or back or erected by rotating around the hinge portion15, the shield13may be opened or closed.

Further, the shield drive device includes the actuator11as a mechanism for driving the shield13.

The actuator11may adopt a step motor, or the like and be installed to be supported on a lower end portion of a projection holder22while being deployed below the shield13.

In addition, a shaft14of the actuator11penetrates and is coupled to a shield arm16positioned in the shield and in this case, the end of the shaft14may be supported while fitting in a shaft bracket23formed in a shield holder21.

As a result, when a forward or reverse operation of the actuator11, the shield13may be bent forth or erected back together with the rotating shaft14.

In particular, the actuator11is deployed in line below the shield13, that is, horizontally deployed in line in a horizontal width direction of the lamp assembly10to provide rotational drive force in the same direction as the rotational direction of the shield13.

That is, the axial rotational direction of the actuator11and the rotational direction of the shield may be set to the same direction.

Further, the shield drive device includes a sliding contact member17as a device for providing friction contact force for controlling the shield motion.

The sliding contact member17may have a disk shape and be installed to be fixed on to a front surface of the actuator11through a rear surface.

A front surface of the sliding contact member17installed as above may be deployed to be close to the shield arm while facing the shield arm16positioned in the shield13.

Of course, the shaft14of the actuator11just penetrates the center of the sliding contact member17to extend forward and thereafter, be coupled to the shield arm.

The sliding contact member17serves to provide the friction contact force when the shield rotates.

That is, a sliding stopper18to be described below causes friction while contacting the front surface of the sliding contact member17, and as a result, a moving speed of the shield13may be controlled by the contact friction.

Further, the shield drive device substantially includes a stopper18and a spring19as mechanisms for decelerating and controlling the motion of the shield13.

The sliding stopper18and the spring19are mounted to be inserted into a stopper mounted groove24formed in the shield arm16of the shield13to contact the sliding contact member17when the shield rotates.

That is, the spring19and the sliding stopper18are sequentially inserted and mounted from the inside of the stopper mounted groove24and a front portion of the sliding stopper18protrudes out of the stopper mounted groove24to contact the front surface of the sliding contact member17just in front thereof.

Herein, the spring19continuously exerts force to push the sliding stopper18out of the groove while elastically supporting the sliding stopper18.

In addition, the sliding stopper18may be compressed or uncompressed (restored) by a height difference of an inclination surface20to be described below while contacting the sliding contact member17, and as a result, the shield motion speed may be decelerated and controlled by pressed force exerted while the sliding stopper18is compressed and restored.

In particular, a plurality of sliding stoppers18and springs19is provided, for example, two stoppers18and springs19are provided in an upper and lower sides and the upper sliding stopper18serves to control a speed when the shield is opened and the lower sliding stopper18serves to control a speed when the shield is closed.

FIG. 3is a perspective view illustrating a shield, a sliding stopper, a spring, and a sliding contact member in the shield drive device according to various embodiments of the present invention.

As illustrated inFIG. 3, herein, a form of the shield13and a form of the sliding contact member17are shown.

The shield arm16and the bar-shaped hinge portion15are vertically formed at both sides of the bottom of a body part of the shield13and each of a set of springs19and sliding stoppers18is mounted in two stopper mounted grooves24formed in the shield arm16.

The hinge portion15of the shield13is supported on the shield holder through a pin fastening structure and the supported shield13may rotate around a lower pin fastening portion of the hinge portion15as a center shaft.

Further, the sliding contact member17has the disk shape and the inclination surface20having a height difference in a circumferential direction is formed on the front surface of the sliding contact member17.

As a result, while the shield-side sliding stopper18is progressed along an inclination surface section, the sliding stopper18may be compressed while being pressed by an inclination surface structure which is heightened in a progress direction and consequently, the shield deceleration control may be achieved by the friction force which is strongly exerted while the sliding stopper18is compressed.

The inclination surface20may be constituted by two inclination surfaces20aand20bhaving a phase difference of 180° from each other and in this case, the respective inclination surfaces20aand20bmay be constituted by inclination surfaces which are gradually heightened in opposite directions to each other based on the circumferential direction.

For example, one inclination surface20acontacted by the upper sliding stopper18when the shield is opened may be constituted by an inclination surface which is gradually heightened from a start point P1to an end point P2in the circumferential direction.

Further, the other one inclination surface20bcontacted by the lower sliding stopper18when the shield is closed may be constituted by an inclination surface which is gradually lowered from a start point P3to an end point P4in the circumferential direction.

As a result, when the shield is opened and closed, one sliding stopper18may be progressed along the inclination surface which is gradually heightened and simultaneously, the other one sliding stopper18may be progressed along the inclination surface which is gradually lowered.

Therefore, an operational state of the shield drive device configured as above will be described below.

FIGS. 4A and 4Bare a perspective view and a cross-sectional view illustrating a state when the shield is closed in the shield drive device according to various embodiments of the present invention.FIGS. 5A and 5Bare a perspective view and a cross-sectional view illustrating a state when the shield is opened in the shield drive device according to various embodiments of the present invention.

As illustrated inFIGS. 4A and 4BandFIGS. 5A and 5B, herein, a shield closing state is a state in which the low beam of the lamp is implemented and a shield opening state is a state in which the high beam of the lamp is implemented.

First, a state when the low-beam state is switched to the high-beam state will be described below.

In the shield closing state, the upper sliding stopper18ais positioned at the start point P1of the upper inclination surface20aof the sliding contact member17and the lower sliding stopper18bis positioned at the start point P3of the lower inclination surface20b.

In this state, when the shield13starts to rotate by driving of the actuator, the upper sliding stopper18ais progressed along the inclination surface20awhich is gradually heightened and in this case, the sliding stopper18ais gradually further compressed as the sliding stopper18acomes close to the end point P2and when the sliding stopper18ais positioned at the end point P2, the sliding stopper18ais maximally compressed.

Simultaneously, the lower sliding stopper18bis progressed along the inclination surface20bwhich is gradually lowered and in this case, the sliding stopper18bis gradually changed from an initial compression state to a release state as the sliding stopper18bcomes close to the end point P4and when the sliding stopper18bis positioned at the end point P4, the sliding stopper18bis completely restored.

By the gradually increasing contact friction force exerted while the upper sliding stopper is compressed when the shield is opened, the shield is initially rapidly opened when being opened and thereafter, gradually slows down when the shield stops, and as a result, the impact when the shield is opened is reduced and the noise is not generated.

Next, a state when the high-beam state is switched to the low-beam state will be described below.

In the shield opening state, the upper sliding stopper18ais positioned at the end point P2of the upper inclination surface20aof the sliding contact member17and the lower sliding stopper18bis positioned at the end point P4of the lower inclination surface20b.

In this state, when the shield13starts to rotate by the driving of the actuator, the lower sliding stopper18bis progressed along the inclination surface20bwhich is gradually heightened and in this case, the sliding stopper18bis gradually further compressed as the sliding stopper18acomes close to the start point P3and when the sliding stopper18ais positioned at the end point P3, the sliding stopper18ais maximally compressed.

Simultaneously, the upper sliding stopper18ais progressed along the inclination surface20awhich is gradually lowered and in this case, the sliding stopper18ais gradually changed from the initial compression state to the release state as the sliding stopper18acomes close to the start point P1and when the sliding stopper18ais positioned at the start point P1, the sliding stopper18ais completely restored.

By the gradually increasing contact friction force exerted while the lower sliding stopper is compressed when the shield is closed, the shield is initially rapidly closed when being closed and thereafter, gradually slows down when the shield stops, and as a result, the impact when the shield is closed is reduced and the noise is not generated.

Meanwhile, the actuator may adopt a step motor without a coil spring (not illustrated) and in this case, while power is not applied, the shield closing state may be maintained by restoration force of the coil spring.

Of course, twisting stress of the coil spring is increased when the shield is opened by driving the step motor depending on the application of the power to store the restoration force.

As such, in the present invention, a shield driving scheme is implemented, in which when the shield is opened, an opening speed of the shield is decelerated and controlled while one sliding stopper is compressed and when the shield is closed, a closing speed of the shield is decelerated and controlled while the other one sliding stopper is compressed to secure shield driving quality such as reducing the generation of the noise when the shield is opened and closed, and the like.