GB2301427A

GB2301427A - A vehicle headlamp

Info

Publication number: GB2301427A
Application number: GB9607672A
Authority: GB
Inventors: Toshiyuki Katsumata; Michinobu Kibayashi
Original assignee: Koito Manufacturing Co Ltd
Current assignee: Koito Manufacturing Co Ltd
Priority date: 1995-04-14
Filing date: 1996-04-12
Publication date: 1996-12-04
Anticipated expiration: 2016-04-12
Also published as: JPH08339703A; JP3141276B2; GB9607672D0; GB2301427B

Abstract

A vehicle headlamp comprises: a surrounding wall having a cylindrical shape, the surrounding wall being arranged at a rear of a lamp body such that the surrounding wall surrounds a bulb attaching portion and externally engaged with a socket cover, wherein the surrounding wall includes an interlocking edge protruding inward from the rear end portion of the surrounding wall; a body engaging portion integrated with the socket cover, the body engaging portion engaging with the surrounding wall, the body engaging portion including, an engaging wall having a cylindrical shape externally engaged with the surrounding wall, the engaging wall being integrated with the body engaging portion, and a interlocking wall arranged inside the engaging wall, the cylindrical interlocking wall being integrated with the body engaging portion, wherein the interlocking wall includes a cylindrical portion and an interlocking protrusion arranged on the cylidrical portion for interlocking with the interlocking edge; and a bulb engaging portion having a cylindrical shape, wherein the bulb engaging portion is externally engaged with a base portion of the bulb inside the body engaging portion and integrated with the socket cover.

Description

LIGHTING DEVICE FOR AUTOMOBILE The present invention relates to a lighting device for an automobile. More particularly, the present invention relates to a socket cover is attached to a lamp body strongly and a sealing performance in the lighting device space is highly enhanced.

Concerning a lighting device used for an automobile, in order to enhance the sealing property around a bulb of the lighting device and prevent water and dust from getting into a lighting device space, there is provided a socket cover attached at the rear of a lamp body.

Fig. 13 is a view showing a conventional lighting device a for an automobile described above. At the substantial center of the rear portion of a lamp body b, there is formed a bulb attaching hole c. In the bulb attaching hole c, a bulb d is detachably attached. In this case, reference character e is a base portion of the bulb d.

Further, behind the lamp body b, there is provided a cylindrical surrounding wall f which protrudes in such a manner that the cylindrical surrounding wall f surrounds the bulb attaching hole c. From the rear end of the surrounding wall f, an interlocking edge g protrudes outward in such a manner that the interlocking edge g continues in the circumferential direction.

The socket cover h is attached to the lamp body b when the surrounding wall f of the lamp body b is engaged with an outer circumferential wall i and when the base portion e of the bulb d is engaged with an inner circumferential wall j. At this time, an interlocking groove k formed on the inner circumferential surface of the outer circumferential wall i is interlocked with the interlocking edge g, so that a fore end portion 1, which is formed to be thin, ofthe outer circumferential wall i is elastically contacted with the rear surface of the lamp body b.

However, in the above arrangement, the outer circumferential wall i of the socket cover h is externally engaged with the surrounding wall f of the lamp body b.

Therefore, the fore end portion 1, which is formed to be thin, of the outer circumferential wall i tends to open outward. Accordingly, in some cases, the fore end portion 1 does not come into close contact with the lamp body b. For this reason, there is a possibility that water and dust enters the lighting device space from a gap formed between the fore end portion 1 and the lamp body b.

In order to solve the ploblems, a first aspect of the present invention provides a lighting device for an automobile in which a lamp body has a front opening, a front lens is attached to the front opening of a lamp body, a bulb is attached at a bulb attaching portion of the lamp body, and a socket cover is attached at the rear of the lamp body thus attaching the bulb, the lighting device comprising:: a surrounding wall having a cylindrical shape, the surrounding wall being arranged at the rear of the lamp body such that the surrounding wall surrounds the bulb attaching portion and externally engaged with the socket cover, wherein the surrounding wall includes an interlocking edge protruding inward from the rear end portion of the surrounding wall;; a body engaging portion integrated with the socket cover, the body engaing portion engaging with the surrounding wall, the body engaging portion including, an engaging wall having a cylindrical shape externally engaged with the surrounding wall, the engaging wall being integrated with the body engaging portion, and a interlocking wall arranged inside the engaging wall, the cylindrical interlocking wall being integrated with the body engaging portion, wherein the interlocking wall includes a cylindrical portion and an interlocking protrusion arranged on the cylidrical portion for interlocking with the interlocking edge; and a bulb engaging portion having a cylindrical shape, wherein the bulb engaging portion is externally engaged with a base portion of the bulb inside the body engaging portion and integrated with the socket cover.

A second aspect of the invention provides the lighting device for an automobile according to the first aspect, wherein a large number of fine annular protrusions are formed on an inner cylindrical surface of the engaging wall of the body engaging portion of the socket cover.

A third aspect of the invention provides the lighting device for an automobile according to one of the first and second asepcts, wherein a large number of fine annular protrusions are formed on an inner cylindrical surface of the bulb engaging portion of the socket cover.

A fourth aspect of the invention provides the lighting device for an automobile according to the first aspect, wherein the surrounding wall includes slits extending in the circumferential direction are arranged at several positions located at intervals in the circumferential direction along the inside edge thereof and locations and sizes of the slits correspond to the interlocking edge.

A fifth aspect of the invention provides the lighting device for an automobile according to the fourth aspect, wherein the surrounding wall further includes ribs formed at both end edges of the inside edge thereof in the longitudinal direction of the slit.

A sixth aspect of the invention provides the lighting device for an automobile according to the fourth aspect, wherein the interlocking wall of the body engaging portion of the socket cover is formed at a position corresponding to the slit.

Accordingly, in the lighting device used for an automobile of the present invention, at the rear end portion of the surrounding wall, there is provided an interlocking edge which protrudes inward, and the interlocking edge is interlocked with the interlocking protrusion of the socket cover from the inside of the surrounding wall. Therefore, the engaging wall is not opened outward, and the lamp body more closely comes into contact with the socket cover.

Consequently, it becomes possible to prevent water and dust from entering the lighting device space.

Also, the engaging wall can not be opened outward.

Further, when the interlocking protrusion on the interlocking wall is interlocked with the interlocking edge on the surrounding wall, there is provided a remarkable response feeling. Accordingly, it is easy to know that the socket cover has been positively attached to the lamp body, and the moderation feeling can be improved in the attaching work so that an inappropriate attaching work can be avoided.

In the accompanying drawings: Fig. 1 is a horizontal cross-sectional view of a lighting device for an automobile of the present invention; Fig. 2 is a view taken in the direction indicated by reference character II in Fig. 1; Fig. 3 is an enlarged cross-sectional view taken on line 111 - III in Fig. 2; Fig. 4 is a view taken in the direction indicated by reference character IV in Fig. 3; Fig. 5 is an enlarged cross-sectional view of a primary portion showing a condition of the formation of the lamp body; Fig. 6 is a rear view of the socket cover; Fig. 7 is a front view of the socket cover; Fig. 8 is a cross-sectional view taken on line VIII VIII in Fig. 6; Fig. 9 is an enlarged cross-sectional view showing the second embodiment of a lighting device for an automobile of the present invention; ; Fig. 10 is a rear view showing a condition in which the socket cover is removed; Fig. 11 is a view showing the third embodiment of a lighting device for an automobile of the present invention, more specifically, showing a rear face of the lamp body and a front face of the socket cover in a condition before the socket cover is attached to the lamp body; Fig. 12 is a longitudinal cross-sectional view showing a condition in which the socket cover is attached to the lamp body; and Fig. 13 is a cross-sectional view showing a conventional lighting device for an automobile.

Referring to the accompanying drawings, an embodiment of a lighting device for an automobile of the present invention will be explained below in detail.

Figs. 1 to 8 are views showing the first embodiment of the lighting device applied to an automobile headlamp 1 of the present invention.

In this embodiment, a lamp body 2 is made of synthetic resin by means of molding. The lamp body 2 has a recess 3 which is open in the front direction. An inner face of the recess 3 undergoes a reflection processing, so that the inner face is formed into a reflecting surface 4.

The reflecting surface 4 has, for instance, a paraboloid revolution.

A front lens is attached to the lamp body 2 in such a manner that the front lens 2 covers a front opening of the lamp body 2.

A bulb attaching hole 6 is formed at the center of the rear portion of the lamp body 2. A bulb 7 is detachably set in the bulb attaching hole 6. Reference numeral 8 is a base portion of the bulb 7.

In a portion which surrounds the bulb attaching hole 6 on the back face of the lamp body 2, there is provided a short cylindrical surrounding wall 9 which protrudes backward.

At positions coming into contact with the inner edge of the base end portion of the surrounding wall 9 on the rear face of the lamp body 2, there are provided slits 10 which extend in the circumferential direction at intervals.

In this connection, one of the slits 10 is located at a position right above the center, and the other two slits 10 are located at obliquely downward positions with respect to the center.

Interlocking edges protrude 11 inward from the rear end of the surrounding wall 9, wherein the interlocking edges protrude at positions separate from each other in the circumferential direction. The positions at which the interlocking edges 11 are formed, and the shapes of the interlocking edges 11 are determined in such a manner that the positions and the shapes are substantially the same as those of the slits 10 when a view is taken from the back.

Accordingly, as shown in Fig. 5, it is possible to form the interlocking edges 11 which are means for positively attaching the socket cover to the lamp body 2, simultaneously with the formation of the lamp body 2 when a portion of the metallic molds 12 (only one metallic mold is shown in the drawing) located inside the lamp body 2 is inserted into one of the slits 10 and arranged inside one of the interlocking edges 11. As a result, it is not necessary to provide an after-process after the lamp body 2 has been formed and the manufacturing cost can be reduced.

In this embodiment, a socket cover 13 is made of elastic material such as natural rubber or synthetic rubber.

The socket cover 13 includes: a short cylindrical bulb engaging portion 14; and a short cylindrical body engaging portion 15, the diameter of which is larger than that of the bulb engaging portion 14, wherein the bulb engaging portion 14 and the body engaging portion 15 are integrated with each other by a thin back face wall 16.

As described above, the bulb engaging portion 14 is formed into a short cylindrical shape, and a large number of fine annular protrusions 17 are formed on the overall inner circumferential surface.

As described above, the body engaging portion 15 is also formed into a short cylindrical shape. The body engaging portion 15 includes: an engaging wall 18 arranged on the outer circumferential side; and an interlocking wall 19 arranged on the inner circumferential side, wherein the engaging wall 18 and the interlocking wall 19 are connected with each other at the rear ends. The length of the interlocking wall 19 is approximately a half of the length of the engaging wall 18. There is formed an engaging groove 20, which is open in the front direction, between the engaging wall 18 and the interlocking wall 19.

At the front end of the interlocking wall 19, there is provided an interlocking protrusion 21 which protrudes to the engaging wall 18 and continues in the circumferential direction.

Also on the inner circumferential surface of the engaging wall 18 except for the rear end portion, in the same manner as that of the inner circumferential surface of the bulb engaging portion 14, there are formed a large number of fine annular protrusions 22.

The back face wall 16 is formed annular, and circumferential walls are respectively formed at the outer and the inner circumferential edge of the back face wall 16.

As shown in Fig. 8, the outer circumferential wall is connected with an inner edge of the rear end of the body engaging portion 15, and the inner circumferential wall is connected with an outer edge of the rear end of the bulb engaging portion 14.

A covering wall 23 protrudes from the back face wall 16. The covering wall 23 is provided in such a manner that it substantially is positioned above the base portion 8 of the bulb 7 when the socket cover 13 is attached to the lamp body 2. The covering wall 23 is mainly used when the socket cover 13 engaged with the lamp body 2 is removed. In this case, the covering wall 23 is held and pulled so as to remove the socket cover 13.

In this embodiment, the socket cover 13 is attached to the lamp body 2 as follows.

The body engaging portion 15 is externally engaged with the surrounding wall 9, and the bulb engaging portion 14 is externally engaged with the base portion 8 of the bulb 7.

At this time, the rear end portion of the surrounding wall 9 is engaged with the interlocking groove 20 of the body engaging portion 15. The interlocking edges 11 of the surrounding wall 9 are located at and engaged with the rear of the interlocking protrusion 21 of the socket cover 13.

Due to the foregoing engagement, it becomes difficult for the socket cover 13 to be separated from the surrounding wall 9, and at the same time the socket cover 13 is closely contacted with the lamp body 2 on the contact surface.

That is, the protrusions 17 of the bulb engaging portion 14 come into strong elastic contact with the outer circumferential surface of the base portion 8 of the bulb 7, and the protrusions 22 of the body engaging portion 15 also come into strong elastic contact with the outer circumferential surface of the surrounding wall 9, so that the ends of the protrusions are crushed and the protrusions are closely contacted with the outer circumferential surface.

Accordingly, the water proofing properties of these contact portions can be maintained high.

Further, the socket cover 13 is formed into a double engaging structure in such a manner that the interlocking edges 11 protruding inward from the surrounding wall 9 are interlocked with the interlocking protrusions 21 of the interlocking wall 19 inside both the surrounding wall 9 and the engaging wall 18 which is externally engaged with the surrounding wall 9. Due to the above double engaging structure, it is possible to make the surrounding wall 9 to closely come into contact with the engaging wall 18 at all times without being affected by the conditions of the surrounding wall 9 and the engaging wall 18.For example, even when the engaging wall 18 of the socket cover 13 gets rolled up for some reasons in the case of attaching the head lamp 1 to a vehicle body, the interlocking edges 11 inside the engaging wall 18 are interlocked with the interlocking protrusions 21 in a stable condition at all times, so that they are not disconnected from each other. Accordingly, the surrounding wall 9 can be closely contacted with the engaging wall 18 again.

Further, when the interlocking edges 11 are interlocked with the interlocking protrusions 21, the interlocking edges 11 get on the interlocking protrusions 21 and then interlock with them. Accordingly, it is possible to provide a moderation feeling in the interlocking work.

Therefore, it is possible for an operator to know that the socket cover 13 has been positively attached to the lamp body 2.

In the above first embodiment, both the interlocking wall 19 of the socket cover 13 and the interlocking protrusion 21 formed on the interlocking wall 19 are continuously provided in the circumferential direction.

However, the interlocking edges 11 of the lamp body 2 with which the interlocking protrusion 21 is interlocked are formed at positions at the rear end of the surrounding wall 9 corresponding to the positions and shapes of the slits 10.

Accordingly, both the interlocking wall 19 and the interlocking protrusions 21 or alternatively only the interlocking protrusions 21 may be formed being separated in the circumferential direction from each other corresponding to the positions where the interlocking edges 11 are formed.

Next, the second embodiment of the lighting device for an automobile of the present invention will be explained below.

Referring to Figs. 9 and 10, the second embodiment 1A will be explained, in which the lighting device for an automobile of the present invention is applied to a headlamp.

A different point between the head lamp 1A of the second embodiment of the present invention and the head lamp 1 of the first embodiment is a shape of the lamp body, and the socket cover of the second embodiment is the same as the socket cover 13 of the first embodiment. Therefore, like reference numerals are used throughout to designate identical elements of the socket cover, and the explanations are omitted here.

A lamp body 30 is made of synthetic resin by means of molding. The lamp body 30 has a recess 31 which is open in the front direction. An inner face of the recess 31 undergoes a reflection processing, so that the inner face is formed into a reflecting surface 32.

In this embodiment, for example, the reflecting surface 32 has a paraboloid revolution.

A front lens is attached to the lamp body 30 in such a manner that the front lens covers a front opening of the lamp body 30. In this case, the front lens is not shown in the drawing.

A bulb attaching hole 33 is formed at the center of the lamp body 30. A bulb 34 is detachably set in the bulb attaching hole 33. Reference numeral 35 is a base portion of the bulb 34.

In a portion which surrounds the bulb attaching hole 33 on the back face of the lamp body 30, there is provided a short cylindrical surrounding wall 36 in such a manner that the surrounding wall 36 protrudes backward.

An interlocking edge 37 continuously protrudes inward from a rear end of the surrounding wall 36 extending in the circumferential direction.

Next, the attaching work of the socket cover 13 to the lamp body 30 will be explained below.

The body engaging portion 15 of the socket cover 13 is externally engaged with the surrounding wall 36, and the bulb engaging portion 14 is externally engaged with the base portion 35 of the bulb 34.

At this time, the rear end portion of the surrounding wall 36 is engaged with the interlocking groove 20 of the body engaging portion 15. The interlocking edge 37 of the surrounding wall 36 is located at and engaged with the rear of the interlocking protrusion 21 of the socket cover 13.

Due to the foregoing engagement, it becomes difficult for the socket cover 13 to be separated from the surrounding wall 36, and at the same time the socket cover 13 is closely contacted with the lamp body 30.

That is, the protrusions 17 of the bulb engaging portion 14 come into strong elastic contact with the outer circumferential surface of the base portion 35 of the bulb 34, and the protrusions 22 of the body engaging portion 15 also come into strong elastic contact with the outer circumferential surface of the surrounding wall 36, so that the ends of the protrusions are deformed and the protrusions are closely contacted with the outer circumferential surface.

Since the interlocking edge 37 on the surrounding wall 36 of the lamp body 30 is interlocked with the interlocking protrusion 21 of the socket cover 13 on the entire circumference, the lamp body 30 is more closely contacted with the socket cover 13, and the water proof property can be further enhanced.

Figs. 11 and 12 are views showing the third embodiment of the lighting device for an automobile of the present invention.

This third embodiment is different from the first embodiment as follows. There are provided ribs on the surrounding wall of the lamp body; instead of the interlocking wall provided on the entire circumference of the socket cover, there are provided partial inside walls; and there are provided positioning protrusions on the socket cover. Other portions of the third embodiment are the same as those of the first embodiment described before.

Therefore, only the different portions will be explained in detail, and like reference numerals are used throughout to designate identical elements of the third embodiment.

On the surrounding wall 9A provided on the back face of the lamp body 2, at a position right above the center and at positions located obliquely downward with respect to the center, there are provided interlocking edges 38 protruded inward from the rear end portion. Each interlocking edge 38 includes: an oblique face 38a located at the rear of the surrounding wall 9A and displaced to the center side of the surrounding wall 9A as it comes forward; and an interlocking face 38b substantially perpendicular to the axial direction of the surrounding wall 9A, wherein the interlocking face 38b continues to the front end of the oblique face 38a.

Plate-shaped ribs 39 are provided at positions along both end edges of the slits 10 in the longitudinal direction in such a manner that the ribs connect the inside edge of the surrounding wall 9A with the outside edge of a portion where the bulb attaching hole 6 of the lamp body 2 is formed.

The body engaging portion 15 of the socket cover 13A includes: arcuate inside walls 40, 40, 40 which are connected with each other by the rear ends; and an engaging wall 18 located outside the inside walls. The inside walls 40, 40, 40 are formed at positions corresponding to the interlocking edges 38. The length of each inside wall 40 in the longitudinal direction is approximately a half of the length of the engaging wall 18. There are provided engaging grooves 41 which are open to the front direction, between the engaging wall 18 and the inside walls 40.

There are provided interlocking claws 42 protruding outside from the fore end portions of the inside walls 40.

Each interlocking claw 42 includes: an oblique face 42a located on the front side and displaced toward the engaging wall 18 as it comes to the rear side; and an interlocking face 42b which is continued to the rear end of the oblique face 42a and substantially perpendicular to the axial direction of the socket cover 13A.

There are provided positioning protrusions 43 which protrude outward from positions located obliquely upward on the engaging wall 18.

On the back face of the lamp body 2, there is provided a substantially arcuate protective wall 44 which is protruded backward in such a manner that the protective wall 44 surrounds the surrounding wall 9A except for its lower portion. A distance of protrusion of the protective wall 44 which protrudes backward is approximately a half of the distance of protrusion of the surrounding wall 9A. Portions 44a on the protective wall 44 corresponding to the positioning protrusions 43 are formed into a recess-shape which is open to the direction of the center so that the recess-shape corresponds to the shapes of the positioning protrusions 43.

The socket cover 13A is attached to the lamp body 2 in the following manner.

The socket cover 13A is pushed into the lamp body 2 from the rear side so that the body engaging portion 15 can be externally engaged with the surrounding wall 9A and the bulb engaging portion 14 can be externally engaged with the base portion 8 of the bulb 7. At this time, when the positioning protrusions 43, 43 are set at the portions 44a, 44a on the protective wall 44, positioning can be easily conducted.

Then, the oblique face 42a of the interlocking claw 42 on each inside wall 40 comes into contact with the oblique face 38a of each interlocking edge 38 of the surrounding wall 9A. When the socket cover 13A is further pushed into the lamp body 2, the interlocking claw 42 is bent inward. When it exceeds the interlocking edge 38, the interlocking claw 42, which has been bent inward, returns to the initial position, so that the interlocking face 42b is interlocked with the interlocking face 38b of the interlocking edge 38, and the rear end portion of the surrounding wall 9A is engaged with the engaging groove 41 of the body engaging portion 15. Due to the foregoing, the socket cover 13A is attached to the surrounding wall 9A of the lamp body 2.

As described above, the socket cover 13A can be very simply attached to the lamp body 2 as follows. The socket cover 13A is pushed into the lamp body 2 from the rear side so that the body engaging portion can be externally engaged with the surrounding wall 9A and so that the bulb engaging portion 14 can be externally engaged with the base portion 8 of the bulb 7.

After the socket cover 13A has been attached to the lamp body 2, the surrounding wall 9A is interposed between the engaging wall 18 and the inside walls 40 and further the interlocking faces 42b of the interlocking claws 42 on the inside walls 40 are interlocked with the interlocking faces 38b of the interlocking edges 38. Consequently, the socket cover 13A can be stably attached to the lamp body 2, and there is no possibility that the socket cover 13A is disconnected from the lamp body 2.

When the ribs 39 are formed on the surrounding wall 9A, the mechanical strength of the surrounding wall 9A is increased. When the socket cover 13A is attached to the surrounding wall 9A, the ribs 39 come into contact with both end portions of the inside walls 40 in the circumferential direction. Accordingly, the socket cover 13A is prevented from rotating with respect to the surrounding wall 9A in the circumferential direction so that the disconnection of the interlocking claws 42 from the interlocking edges 38 can be suppressed.

As can be seen in the above descriptions, the following effects can be provided by the present invention.

According to the first aspect of the present invention, there are provided interlocking edges which protrude inward from the rear end portion of the surrounding wall, and the interlocking edges and the interlocking protrusions of the socket cover are interlocked with each other from the inside of the surrounding wall. Accordingly, the engaging wall is not opened outward, and the lamp body is more closely contacted with the socket cover. Therefore, water and dust is prevented from getting into the lighting device space.

Further, there is no possibility that the engaging wall is opened outside, and furthermore there is a remarkable response feeling when the interlocking protrusions on the interlocking wall are interlocked with the interlocking edges on the surrounding wall. Accordingly, it is easy to know that the socket cover has been positively attached to the lamp body, and the moderation feeling can be improved so that an inappropriate attaching work can be avoided.

According to the second aspect of the present invention, there are formed a large number of fine annular protrusions on the inner circumferential face of the engaging wall of the body engaging portion of the socket cover, and the protrusions of the body engaging portion come into strong elastic contact with the outer circumferential surface of the surrounding wall, so that the ends of the protrusions are crushed and the protrusions are closely contacted with the outer circumferential surface. Accordingly, the water proofing properties of these contact portions can be maintained high.

According to the third aspect of the present invention, there are provided a large number of fine annular protrusions on the inner circumferential surface of the bulb engaging portion of the socket cover. Accordingly, these protrusions strongly come into elastic contact with the outer circumferential surface of the base portion of the bulb, and the fore ends of the protrusions are crushed. Therefore, the outer circumferential surface of the base portion of the bulb is closely contacted with the inner circumferential surface of the bulb engaging portion of the socket cover, and the water proof property of this contact portion can be enhanced.

According to the fourth of the present invention, at the positions along the inside edge on the surrounding wall of the lamp body, there are provided several slits extending in the circumferential direction, wherein these slits are located being separate from each other. The positions and shapes of these slits correspond to the interlocking edges.

Accordingly, it is possible to form the interlocking edges simultaneously with the formation of the lamp body.

Therefore, it is not necessary to provide an after-process after the lamp body has been formed. As a result, the manufacturing cost can be reduced.

According to the present invention described in the fifth aspect, there are provided ribs at both end edges in the longitudinal direction of the slits of the inside edge of the surrounding wall. Accordingly, it is possible to increase the mechanical strength of the surrounding wall.

According to the present invention described in sixth aspect, the interlocking wall of the socket cover is formed at a position corresponding to the slit. Accordingly, when the socket cover is attached to the surrounding wall, the interlocking wall of the socket cover is surrounded by the interlocking wall of the lamp body, the surrounding wall and the ribs. Therefore, it is possible to prevent the socket cover from being easily disconnected from the lamp body.

Claims

1. A lighting device for an automobile in which a lamp body has a front opening, a front lens is attached to the front opening of a lamp body, a bulb is attached at a bulb attaching portion of the lamp body, and a socket cover is attached at the rear of the lamp body thus attaching the bulb, the lighting device comprising:: a surrounding wall having a cylindrical shape, the surrounding wall being arranged at the rear of the lamp body such that the surrounding wall surrounds the bulb attaching portion and externally engaged with the socket cover, wherein the surrounding wall includes an interlocking edge protruding inward from the rear end portion of the surrounding wall;; a body engaging portion integrated with the socket cover, the body engaing portion engaging with the surrounding wall, the body engaging portion including, an engaging wall having a cylindrical shape externally engaged with the surrounding wall, the engaging wall being integrated with the body engaging portion, and a interlocking wall arranged inside the engaging wall, the cylindrical interlocking wall being integrated with the body engaging portion, wherein the interlocking wall includes a cylindrical portion and an interlocking protrusion arranged on the cylidrical portion for interlocking with the interlocking edge; and a bulb engaging portion having a cylindrical shape, wherein the bulb engaging portion is externally engaged with a base portion of the bulb inside the body engaging portion and integrated with the socket cover.

2. The lighting device for an automobile according to claim 1, wherein a large number of fine annular protrusions are formed on an inner cylindrical surface of the engaging wall of the body engaging portion of the socket cover.

3. The lighting device for an automobile according to one of claims 1 and 2, wherein a large number of fine annular protrusions are formed on an inner cylindrical surface of the bulb engaging portion of the socket cover.

4. The lighting device for an automobile according to claim 1, wherein the surrounding wall includes slits extending in the circumferential direction are arranged at several positions located at intervals in the circumferential direction along the inside edge thereof and locations and sizes of the slits correspond to the interlocking edge.

5. The lighting device for an automobile according to claim 4, wherein the surrounding wall further includes ribs formed at both end edges of the inside edge thereof in the longitudinal direction of the slit.

6. The lighting device for an automobile as claimed in claim 4, wherein the interlocking wall of the body engaging portion of the socket cover is formed at a position corresponding to the slit.

Amendments to the claims have been filed as follows 1. A lighting device for an automobile, the device comprising a hollow lamp body having a front opening and an inner surface formed as a reflecting surface; a front lens attached to the front opening of the lamp body; and a bulb attached at a bulb attaching portion of the lamp body by a socket cover which is attached to the rear of the lamp body; the lamp body having at its rear a cylindrical wall which surrounds the bulb-attaching portion, the radially outer surface of which engages with the socket cover, and which has an interlocking edge protruding radially inwardly from the rear end portion thereof; the socket cover having an integral body-engaging portion including an engaging wall of cylindrical shape engaging around the surrounding wall and an interlocking wall arranged inside the engaging wall and including a cylindrical portion and an interlocking protrusion arranged on the cylindrical portion for interlocking with the interlocking edge; and the socket cover further having an integral cylindrical bulb-engaging portion the radially inner surface of which engages around a base portion of the bulb.

2. A device according to claim 1, wherein a plurality of annular protrusions are formed on an inner cylindrical surface of the engaging wall of the body-engaging portion of the socket cover.

3. A device according to claim 1 or claim 2, wherein a plurality of annular protrusions are formed on an inner cylindrical surface of the bulb-engaging portion of the socket cover.

4. A device according to any one of the preceding claims, wherein a rear wall of the lamp body is formed radially inwardly of the surrounding wall with circumferentially spaced, part circumferentially extending, slits, the locations and extent of which correspond to those of the interlocking edge, which is also formed in circumferentially discontinuous parts.

5. A device according to claim 4, wherein the lamp body further includes ribs formed at both ends of the slits.

6. A device according to claim 4 or claim 5, wherein the interlocking wall of the body-engaging portion of the socket cover is formed at circumferential positions corresponding to the slits.

7. An automobile lamp, substantially as described with references to Figures 1 to 12 of the accompanying drawings.