STEERING SUPPORT LIGHT FOR CAR Technical Field The present invention relates, in general, to a steering support light for cars and, more particularly, to a steering support light designed to turn on a left front support lamp in addition to the head lamps in the case of a left turn while driving the car forward, turn on a right front support lamp in addition to the head lamps in the case of a right turn while driving the car forward, turn on a left rear support lamp in addition to the back-up lamps in the case of a left turn while driving the car backward, and turn on a right rear support lamp in addition to the back-up lamps in the case of a right turn while driving the car backward, thus shining lights into a dark zone during a forward or backward cornering and allowing a driver to safely drive the car at night.

Background Art Fig. 1 shows the construction of a conventional steering support light for cars. As shown in the drawing, the conventional steering support light for cars is consists of a controller 14, left and right front support lamps FL and FR, a first gear 12 and a switching unit 15.

The controller 14 is connected to a battery B set within the engine compartment of a car, while the left and right front support lamps FL and FR are provided at corners of the front end of the car at positions around the two turn signals, and are commonly connected to the controller 14. The first gear 12 is integrally formed on a steering shaft 11 so as to be rotated along with the steering shaft 11 in response to a rotating action of the steering wheel 10. The switching unit 15 comprises a double-staged second gear 16 engaging with the first gear 12 so as to be operated in conjunction with the first gear 12. A third gear 18 engages with the second gear 16. The switching unit 15 also has a limit switch (not shown). This limit switch is operated by the torque of the third gear 18, and is

connected to the battery B through the controller 14 so as to turn on or off an appropriate one of the left and right front support lamps FL and FR.

However, since the switching unit 15 comprises the double-staged second gear 16, the third gear 18 engaging with the second gear 16, and the limit switch operated by the torque of the third gear 18, the switching unit 15 undesirably has a large volume in addition to a complex construction. Therefore the switching unit 15 needs high production cost, which causes high production cost of the steering support lights also.

In addition, the conventional steering support light has left and right front support lamps, but does not have any support lamp at the rear end of a car, and so the light cannot illuminate the dark zone around the rear end of the car during a left or right turn while driving the car backward.

In the conventional steering support light, the left and right front support lamps are turned on within a limited steering angle of the steering wheel, and so it is impossible to enlarge or reduce the illumination angle of the support lamps as desired.

Disclosure of the Invention Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a steering support light for cars, of which the switching unit comprises a second gear engaging with the first gear, and a limit switch brought into contact with the second gear so as to turn on or off the left and right front support lamps in response to a rotation of the second gear, and which thus accomplishes compactness and smallness of the switching unit and reduces the production cost of the steering support lights.

Another object of the present invention is to provide a steering support light for cars, which is provided with left and right rear support lamps in addition to the left and right front support lamps, and which turns on the left or right rear support lamp during a left or right turn while driving a car backward, thus

illuminating the dark zone around the rear end of the car during such a turn at night.

A further object of the present invention is to provide a steering support light for cars, of which the limit switch is provided with a longitudinal shaft hole for assembling the worm gear shaft with the limit switch, and which controls the steering angle of the steering wheel for operating the limit switch by adjusting the interval between the worm gear and the limit switch or by changing the pitches and pitch diameters of the worm and worm gear.

In order to accomplish the above object, the present invention provides a steering support light for cars, comprising a controller connected to a battery of a car, left and right front support lamps provided at corners of the front end of the car and commonly connected to the controller, a first gear integrally formed on the steering shaft so as to be rotated along with the steering shaft, and a switching unit operated in conjunction with the first gear and connected to the controller so as to turn on or off the left and right front support lamps, wherein the first gear is a worm, with a pitch of the worm arranged along the axis of the steering shaft; and the switching unit comprises a worm gear engaging with the worm, a worm gear shaft integrated with the worm gear, and a limit switch arranged to be brought into contact with the worm gear shaft.

The above steering support light further comprises left and right rear support lamps, which are connected to both the back gear unit of the car and the limit switch through the controller so as to be turned on or off in response to an operation of both the back gear unit and the limit switch.

In the steering support light of this invention, the worm gear shaft is integrated with the worm gear into a single structure, and has a stepped circular cross-section with a small-diameter semicircular part and a large-diameter semicircular part.

In addition, the limit switch comprises: a longitudinal shaft hole seating the worm gear shaft therein while allowing the position of the worm gear shaft in the shaft hole to be adjustable as desired; and two switch levers brought into selective contact with the external surface of the small-diameter semicircular part

of the worm gear shaft in response to a rotating action of the worm gear shaft, thus turning on or off the left and right front support lamps or the left and right rear support lamps in addition to the left and right front support lamps.

In the steering support light, the rotating angle of the worm for turning on one of the left and right front support lamps or one of the left and right rear support lamps in addition to an associated one of the left and right front support lamps is changeable by controlling the pitches and pitch diameters of the worm and worm gear.

In another embodiment, the switching unit further comprises: an upper holding plate assembled with the limit switch at a first end thereof and provided with a first opening at a second end thereof, the upper holding plate being fitted over an upper end of the worm of the steering shaft at the opening so as to hold the upper end of the worm ; and a lower holding plate assembled with the limit switch at a first end thereof and provided with a second opening at a second end thereof, the lower holding plate being fitted over a lower end of the worm of the steering shaft so as to hold the worm in cooperation with the upper holding plate.

In the steering support light of this invention, the switching unit consists of the worm and limit switch, and so it is possible to accomplish compactness and smallness of the switching unit and reduce the production cost of the steering support lights.

In addition, the limit switch of this steering support light is provided with the longitudinal shaft hole for assembling the worm gear shaft with the limit switch, and so it is possible to control the steering angle of the steering wheel for operating the limit switch by adjusting the interval between the worm gear and the limit switch without changing the pitches and pitch diameters of the worm and worm gear.

In the steering support light of this invention, the switching unit is assembled with the worm by means of upper and lower holding plates of the limit switch, and so it is possible to easily manufacture the steering support light through a simple production process.

The steering support light of this invention has the left and right rear

support lamps in addition to the left and right front support lamps. The left or right rear support lamp is turned on during a left or right turn while driving a car backward, thus illuminating the dark zone around the rear end of the car during such a turn at night. Therefore, the steering support light of this invention allows a driver to be less likely to have any collision during a left or right turn while driving the car backward at night.

Brief Description of the Drawings The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which: Fig. 1 is a view, showing the construction of a conventional steering support light for cars; Fig. 2 is a view, showing the construction of a steering support light for cars in accordance with the primary embodiment of the present invention; Fig. 3a is a view, showing the movable engagement of a worm of a steering shaft with a switching unit of the steering support light of this invention; Fig. 3b is a view, showing the construction of the limit switch included in the switching unit of the steering support light according to this invention; Fig. 4 is a rear perspective view of a car, showing an arrangement of the left and right rear support lamps included in the steering support light according to this invention; Fig. 5 is a circuit diagram of the steering support light according to this invention; Fig. 6 is a perspective view, showing the arrangement of the steering wheel, steering shaft, worm and switching unit of a steering support light according to the second embodiment of the present invention; Fig. 7a is a view, showing the construction and engagement of the worm and switching unit of the steering support light of Fig. 6 in detail; and Fig. 7b is an exploded perspective view, showing the construction of

upper and lower holding plates attached to the limit switch included in the switching unit of Fig. 7a.

* Description of the reference numerals in the * 10 : steering wheel 11 : steering shaft 12 : first gear 14 : controller 16 : second gear 18 : third gear 20 : back gear unit 22: worm 23 : worm gear 24: worm gear shaft 24L: small-diameter semicircular part of the worm gear shaft 24R: large-diameter semicircular part of the worm gear shaft 26: limit switch 26-2L : first switch lever 26-2R : second switch lever 26-3L : first actuator 26-3R : second actuator 72: upper holding plate 74: lower holding plate Best Mode for Carrying Out the Invention [First Embodiment] Fig. 2 is a view, showing the construction of a steering support light for cars in accordance with the primary embodiment of the present invention. As shown in the drawing, the steering support light of this invention comprises a controller 14 connected to a battery B set within the engine compartment of a car, left and right front support lamps FL and FR provided at corners of the front end of the car at positions around the two turn signals and commonly connected to the controller 14, and a steering shaft 11 integrated with a steering wheel 10. The above-mentioned construction remains the same as conventional steering support lights.

As shown in Fig. 2, the steering support light of this invention also comprises a switch unit 21, a first gear 22, a light receiving sensor S, and left and right rear support lamps RL and RR. The first gear 22 is integrated with the

steering shaft 11 extending from the steering wheel 10, thus being rotated along with the steering shaft 11 in the same direction in response to a steering action of the steering wheel 10. In the present invention, this first gear 22 is a worm, with the pitch of the worm arranged along the axis of the steering shaft 11. The switching unit 21 is operated in conjunction with the rotating action of the worm 22.

As shown in Figs. 2 and 3a, the switching unit 21 comprises a worm gear 23, a worm gear shaft 24 and a limit switch 26. The worm gear 23 engages with the worm 22, while the worm gear shaft 24 is integrated with the worm gear 23.

The limit switch 26 is installed within the engine compartment of the car at a predetermined position, and is arranged to come into contact with the worm gear shaft 24. The limit switch 26 selectively turns on the left and right front support lamps FL and FR through the controller 14, which is set within the engine compartment of the car at a predetermined position.

As shown in Figs. 3a and 3b, the worm gear shaft 24 is integrated with the worm gear 23 into a single structure, and has a stepped circular cross-section with a small-diameter semicircular part 24L and a large-diameter semicircular part 24R.

One of the first and second switch levers 26-2L and 26-2R of the limit switch 26 selectively comes into contact with the small-diameter semicircular part 24L of the shaft 24 in accordance with a rotating action of the worm gear 23, thus allowing an associated one of the first and second actuators 26-3L and 26-3R to move from its retracted position to its extended position and turning on an associated one of the front and rear support lamps FL, FR, RL and RR. A roller 27 is provided at the end of each of the switch levers 26-2L and 26-2R, thus accomplishing a smooth movable contact of the switch levers 26-2L and 26-2R with the external surfaces of small-and large-diameter semicircular parts 24L and 24R of the worm gear shaft 24.

As best seen in Fig. 3b, the limit switch 26 is provided with a longitudinal shaft hole 28 for assembling the worm gear shaft 24 with the limit switch 26.

Due to the longitudinal profile of said shaft hole 28, it is possible to change the rotating angle of the worm gear 23, at which the switch levers 26-2L and 26-2R of

the limit switch 26 initially come into contact with the external surface of the small-diameter semicircular part 24L of the worm gear shaft 24, by adjusting the interval between the worm gear 23 and the limit switch 26 as desired.

As shown in Fig. 2, the light receiving sensor S is provided at the left outside mirror of the car. In response to light beams radiated from a car approaching the driver in back of the driver, the light receiving sensor S keeps the state of the left front support lamp FL inactive regardless of a steering action of the steering wheel.

As shown in Figs. 2 and 4, the left and right rear support lamps RL and RR are connected to both a back gear unit (not shown) of the car and the limit switch 26 through the controller 14 so as to be turned on or off in response to an operation of both the back gear unit and the limit switch 26. Such an electric connection of the two rear support lamps RL and RR to both the back gear unit and the limit switch 26 is shown in Fig. 5, showing the electric circuit of the steering support light of this invention. In the present invention, the two rear support lamps RL and RR are preferably set in the lower outside corners of the two taillights 30 as best seen in Fig. 4, thus shining lights into large areas.

The operational effect of the steering support light of this invention will be described herein below with reference to Figs. 2 to 5.

As shown in Figs. 2, 3a, 3b and 5, the worm 22, integrally formed on the steering shaft 11 at a predetermined position, is rotated along with the steering shaft 11 when the steering wheel 10 is rotated in a direction. Therefore, the worm gear 23, engaging with the worm 22, is rotated in the same direction. Due to the rotating action of the worm gear 23, one of the switch levers 26-2L and 26-2R of the limit switch 26 moves from the large-diameter part 24R of the worm gear shaft 24 to the small-diameter part 24L. An associated one of the two actuators 26-3L and 26-3R of the limit switch 26 is moved from its retracted position to its extended position at a time the switch lever 26-2L or 26-2R reaches the small- diameter part 24L. The limit switch 26 is thus activated at an associated side thereof to turn on an associated one of the two front support lamps FL and FR.

For example, when the steering wheel 10 is rotated counterclockwise to

accomplish a left turn while driving the car forward, the left side of the limit switch 26 is activated to turn on the left front support lamp FL.

When the light receiving sensor S in such a case senses light beams radiated from a car approaching the driver in back of the driver, the sensor S turns off the light receiving sensor switch S-SW of Fig. 5, thus keeping the state of the left front support lamp FL inactive regardless of the steering action of the steering wheel 10.

When the back gear unit is operated with the limit switch 26 activated as described above, the back gear switch R-SW of Fig. 5 is activated to turn on an associated one of the two rear support lamps RL and RR.

[Second Embodiment] Fig. 6 shows the arrangement of the steering wheel, steering shaft, worm and switching unit of a steering support light according to the second embodiment of the present invention. Fig. 7a shows the construction and engagement of the worm and switching unit of the steering support light of Fig. 6. Fig. 7b shows the construction of upper and lower holding plates attached to the limit switch included in the switching unit of Fig. 7a.

As shown in Figs. 7a and 7b, the upper and lower holding plates 72 and 74 are mounted to the upper and lower edges of the limit switch 26 using a plurality of setscrews.

As shown in Figs. 7a and 7b, the upper holding plate 72 has a plurality of screw holes (not shown) at the first end thereof, and is mounted to the limit switch 26 using a plurality of setscrews (not shown). This upper holding plate 72 is also provided with a first opening 72c at the second end thereof, and is fitted over the upper end of the worm 22 of the steering shaft 11 at said opening 72c so as to hold the upper end of the worm 22.

As shown in Figs. 7a and 7b, the lower holding plate 74 has a plurality of screw holes 74a at the first end thereof, and is mounted to the limit switch 26 using a plurality of setscrews 74b. This lower holding plate 74 is also provided with a second opening 74c at the second end thereof, and is fitted over the lower end of

the worm 22 at said opening 74c so as to hold the worm 22 in cooperation with the upper holding plate 72.

In the second embodiment, the general shape of the steering support light except for the upper and lower holding plates mounted to the limits switch 26 remains the same as that described for the primary embodiment, and so the steering support light of this second embodiment provides the same operational effect as that of the primary embodiment.

That is, in the steering support light of the second embodiment, the switching unit is assembled with the worm 22 through the upper and lower holding plates 72 and 74, and so it is possible to simplify the process of producing the steering support light.

Of course, it should be understood that it is possible to appropriately change the construction of the steering support light of this invention from those of the primary and second embodiments without affecting the functioning of this invention.

When the pitches of the worm 22 and worm gear 23 are reduced or the pitch diameter of the worm gear 23 is enlarged while fixing the interval between the worm gear 23 and the limit switch 26, it is possible to reduce the rotating angle of the worm 22 allowing the switch levers 26-2L and 26-2R of the limit switch 26 to initially come into contact with the small-diameter part 24L of the worm gear shaft 24. It is also possible to enlarge the rotating angle of the worm 22, allowing the switch levers 26-2L and 26-2R of the limit switch 26 to initially come into contact with the small-diameter part 24L of the worm gear shaft 24, by reducing the pitches of the worm 22 and worm gear 23 or enlarging the pitch diameter of the worm gear 23 while fixing the interval between the worm gear 23 and the limit switch 26.

On the other hand, the rotating angle of the worm 22 allowing the switch levers 26-2L and 26-2R of the limit switch 26 to initially come into contact with the small-diameter part 24L of the worm gear shaft 24 may be also enlarged by increasing the arc length of the large-diameter semicircular part 24R of the worm gear shaft 24 and reducing the arc length of the small-diameter semicircular part

24L. It is also possible to reduce the rotating angle of the worm 22 by reducing the arc length of the large-diameter semicircular part 24R of the worm gear shaft 24 and enlarging the arc length of the small-diameter semicircular part 24L.

In the primary and second embodiments, the shaft hole 28 of the limit switch 26 has a longitudinal profile. However, it should be understood that the shaft hole 28 may have another profile, for example, a circular profile. However, it should be understood that some profiles of the shaft hole 28 may prevent an adjustment of the interval between the worm gear 23 and the limit switch 26.

In the preferred embodiments of this invention, the light receiving sensor S is provided at the left outside mirror of the car. However, the light receiving sensor S may be installed at the right outside mirror of the car in place of the left outside mirror. That is, it is necessary to install the light receiving sensor S at the right outside mirror of a car when the steering wheel is positioned at the right-hand side within the passenger compartment of the car, such as in cars used in Japan or England.

In addition, the light receiving sensor S is installed at the front portion of the car in the preferred embodiments of this invention. However, it should be understood that two light receiving sensors may be installed at both sides of the rear portion of the car. In such a case, the light receiving sensors, provided at both sides of the rear portion of the car, turn off the left and right rear support lamps in response to light beams radiated from a car approaching the driver in back of the driver regardless of a steering action of the steering wheel.

In the preferred embodiments of this invention, when one of the two rear support lamps is turned on, an associated one of the front support lamps FL and FR is turned on at the same time. However, it should be understood that it is possible to design the steering support light of this invention such that the front support lamps FL and FR are left in their states inactive regardless of the activated states of the rear support lamps by connecting the electric wires of the front support lamps FL and FR to the back gear switch such that the front support lamps FL and FR are turned off during an operation of the back gear unit.

In the second embodiment, the upper and lower holding plates 72 and 74 are mounted to the limit switch 26 using a plurality of setscrews. However, it should be understood that the upper and lower holding plates 72 and 74 may be mounted to the limit switch 26 through another conventional process, such as a riveting process or a welding process.