Device for fitting headlight with lamp for vehicle

Abstract: A device (1) for fitting a headlight with a lamp (20) for a vehicle includes a flange receiving portion (2) for receiving a bayonet flange (21) of the lamp, three recesses (2a) formed on the flange receiving portion (2) for receiving three outer pawls (22) radially projecting from the bayonet flange (21), and a substantially circular retainer spring (3) made of a piano wire, a stainless steel wire or the like and adapted to be fastened to the flange receiving portion (2) by threadably tightening three screws (4). Three substantially U-shaped retaining portions (3a) are formed along the retainer spring (3) in the equally spaced relationship as seen in the circumferential direction so as to enable each outer pawl (22) to be firmly held between the bottom of each recess (2a) and the corresponding retaining portion (3a) in the clamped state. When the lamp (20) is fitted in the headlight, it is turned to a predetermined position from the initial position where the outer pawls (22) are initially received in the recesses (2a) formed on the flange receiving portion (2). To assure that the outer pawls (22) of the bayonet flange (21) are firmly held on the flange receiving portion (2) without any necessity for threadably tightening screws (4), the outer pawls (22) may be received in fitting slits between a plurality of slantwise upward extending projections and the bottom surfaces of the recesses formed on the flange receiving portion (2) with the exception of one outer pawl (22) having a substantially U-shaped retaining portion (3a) of the substantially circular retainer spring (3) placed thereon. Each of the slantwise upward extending projections is integrated with the flange receiving portion (2).

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to a lighting instrument such as a headlight, an auxiliary headlight or the like for a vehicle. More particularly, the present invention relates to improvement of a device for fitting a headlight with a lamp for a vehicle. 2. Background Art To facilitate understanding of the present invention, a typical conventional device for fitting a headlight with a lamp for a vehicle (hereinafter referred to simply as a device) will be described below with reference to Fig. 5. The device includes a lamp fitting portion 90 for a headlight 10 through which a lamp 20 is received in the interior of the headlight 10. The lamp 20 includes a bayonet flange 21 having three outer pawls 22 radially projecting therefrom. To receive the outer pawls 22 in the lamp fitting portion 90, three recesses 91a are formed on a flange holding portion 91 of the lamp fitting portion 90. As shown in Fig. 5, the flange holding portion 91 is integrated with the headlight 10 of which upper end part is covered with a turnable cap 92. To firmly hold the outer pawls 22 in the recesses 91a, three cutouts 92a are formed on the cap 92, and moreover, the cap 92 includes three inner pawl portions 92b corresponding to the outer pawls 22. When the headlight 10 is fitted with the lamp 20, first, the cutouts 92a on the flange holding portion 92 are located in alignment with the recesses 91a of the flange holding portion 91 so that the outer pawls 22 of the bayonet flange 21 are placed on the recesses 91a of the flange portion 91 through the cutouts 92a from above. At this time, the lamp 20 is inserted into the headlight 10 by passing past the circular opening defined by the three cutouts 92a and the three inner pawl portions 92b on the cap 92. Thereafter, the cap 92 is turned in a certain direction, e.g., in the clockwise direction until the outer pawls 22 are located below the inner pawl portion 92b in the overlapped state, resulting in the lamp 20 being firmly fitted in the headlight 10 with the aid of the device. With the conventional device constructed in the above-described manner, however, various requests have been hitherto raised from users for improving the present properties of the device. Typically, one of the requests is such that the lamp 20 is located at the position where it is inserted into in the headlight 10 when the cap 92 is turned in a certain direction, e.g., in the anticlockwise direction, and subsequently, it is immovably held at the position where it is firmly fitted in the headlight 10 when the cap 92 is turned in the clockwise direction. The other one is such that there does not arise a malfunction that the cap 92 is readily disconnected from the flange portion 91 during running of a vehicle. Because of these requests, the conventional device becomes unavoidably complicated in structure, resulting in the device being fabricated at an increased cost. From DE-A-38 26 106 there is known a generally similar device for fitting a headlight with a lamp for a vehicle, in which the means for holding the outer pawls of the bayonet flange against rotational and vertical movement comprise sections of the legs of a substantially triangular retainer spring fixed at the flange holding portion and made of wire having excellent resiliency and covering partly the recesses formed on the flange holding or receiving portion, so that after placing the outer pawls in the said recesses the outer pawls by rotation will be moved under the said sections of the legs of the retainer spring, thus holding the outer pawls against unintentional movement. The known retainer spring is anchored at the outer circumferential side of the flange holding portion by forcing respective sections of the spring over projections provided on the outer circumferential surface of the flange holding portion, said projections having inclined surfaces over which the spring must be forced in order to said spring being able to enter slots provided in said projections. In order to effect such difficult snapping and pushing action of the spring a complicate shape of said spring is necessary including bending the spring in two different planes, namely a horizontal plane and a vertical plane, so that the manufacture of the retainer spring is quite complicate. Additionally, it is difficult to mould the projections on the outer circumferential surface of the flange holding portion because there is needed a specific mould, e.g. a sliding mould and thus the cost for preparing such a mould and moulding such a headlight is quite high. In view of the problems of the prior devices according to the present invention there has been provided a device for fitting a headlight with a lamp for a vehicle as defined by claim 1. In a device according to the invention the retainer spring has a relatively simple configuration and thus its manufacture is simple and cheap. Moreover, the retainer spring is mounted without any pretension by simply using screws screwed into respective holes provided in the upper surface of the flange receiving portion. Further preferred features of the device according to claim 1 are defined by claims 2 to 5. A somewhat modified device according to the invention is defined by claim 6. Further preferred features of the device according to claim 6 are defined by claim 7 and 8. From US-A-4 760 506 there is known a device of the general type in question, in which fitting slots receiving the outer pawls are formed by engaging parts provided on a fixture of the socket of the headlight which fixture is to be mounted at the respective end surface of the flange holding or receiving portion. Said engaging parts cover partly the recesses of the flange receiving portion and have an elastic substantially V-shaped locking piece for positively holding the respective outer pawl. Other objects, features and advantages of the present invention will become apparent from reading the following description which has been made in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS The present invention is illustrated in the following drawings in which: Fig. 1 is a perspective view of a device for fitting a headlight with a lamp for a vehicle according to a first embodiment of the present invention, particularly showing essential components constituting the device in the disassembled state; Fig. 2 is a plan view of the device shown in Fig. 1 wherein the device is seen in the direction of inserting of the lamp; Fig. 3 is a perspective view of a device for fitting a headlight with a lamp for a vehicle according to a second embodiment of the present invention, particularly showing essential components constituting the device in the disassembled state; Fig. 4 is a pan view of the device shown in Fig. 3 wherein the device is seen in the direction of inserting of the lamp, and Fig. 5 is a perspective view of a conventional device for fitting a headlight with a lamp for a vehicle. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail hereinafter with reference to the accompanying drawings which illustrate a few preferred embodiments thereof. First, a device for fitting a headlight with a lamp for a vehicle according to a first embodiment of the present invention will be described below with reference to Fig. 1 and Fig. 2. Incidentally, same components as those constituting the conventional device of the foregoing type shown in Fig. 5 are represented by same reference numerals. In the drawings, reference numeral 1 generally designates a device for fitting a headlight with a lamp for a vehicle (hereinafter referred to simply as a device) wherein the device 1 is constructed according to the first embodiment of the present invention. The device 1 is substantially identical with the conventional device with the exception that a flange receiving portion 2 for receiving a bayonet flange 21 of a lamp 20 therein is designed in the different manner from that of the conventional device. Specifically, three recesses 2a are formed on the flange receiving portion 2 for receiving three outer pawls 22 projecting outward of the bayonet flange 21 therein, and each of the recesses 2a is dimensioned to have the substantially same depth as the thickness of each outer pawl 22. In addition, device 1 includes a retainer spring 3 made of a piano wire, a stainless wire or the like, and the retainer spring 3 is designed in the arc-shaped contour in such a manner that it has an outer diameter larger than that of each outer pawl 22, and three substantially U-shaped retaining portions 3a are formed inside of the circular locus of the retainer spring 3. As is apparent from Fig. 1, the retainer spring 3 is firmly fastened to the flange receiving portion 2 by threadably fitting three screws 4 into the corresponding female-threaded holes formed in the flange receiving portion 2 and then tightening the screws 4. At the time of screw tightening, it is important that each retaining portion 3a is located at the right-hand part of the corresponding recess 2a as seen from above in the clockwise direction in Fig. 2 so as to enable the corresponding outer pawl 22 to be received below the retaining portion 3a without fail. When a headlight 10 is fitted with a lamp 20 with the aid of the device 1, first, the left-hand end of each outer pawl 22 as seen in the anticlockwise direction in Fig. 1 is located in alignment with the left-hand end of each recess 2a, thereafter, three outer pawls 22 are placed on three recesses 2a from above, and subsequently, the lamp 20 is turned in the clockwise direction with an operator's hand so that each outer pawl 22 is firmly held between the bottom surface of the recess 2a and the retaining portion 3a of the retainer spring 3 in the clamped state by the resilient force of the retainer spring 3. The turning movement of the lamp 20 is stopped when the right-hand end of the outer pawl 22 comes in contact with the right-hand end of the recess 2a as seen in the clockwise direction. At this time, the lamp 20 is fitted to the headlight 10 at the correct position predetermined relative to the headlight 10. Next, a device for fitting a headlight with a lamp for a vehicle (hereinafter referred to simply as a device) according to a second embodiment of the present invention will be described below with reference to Fig. 3 and Fig. 4. Similarly, same components as those in the preceding embodiment are represented by same reference numerals. The device 1 constructed according to the second embodiment of the present invention is substantially identical with the device constructed according to the first embodiment with the exception that only a single retaining portion 3a is formed on a retainer spring 3 and no tightening screw is used for the device 1 in contrast with the first embodiment wherein three retaining portions 3a are formed along the arc-shape locus of the retainer spring 3 and three tightening screws 4 are used for the device 1. In other words, it is not necessary that the same number of retaining portions 3a as that of the recesses (three recesses in the shown case) are formed on the retainer spring 3, and it suffices that the number of retaining portions 3a enough to firmly hold the lamp 20 at a predetermined position in the device 1 (single retaining portion 3a in the second embodiment) is formed on the retainer spring 3. Specifically, a single retaining portion 3a is formed on the retainer spring 3 corresponding to one of three recesses 2a on the flange receiving portion 2, and a fitting slot 2b is formed at the right-hand end of each of two recesses 2a as seen in Fig. 3 on which no retaining portion is formed. The fitting slot 2b is intended to firmly hold the corresponding outer pawl 22 of the bayonet flange 21 in the clamped state after the outer pawl 22 is received in the recess 2a and then turned in the clockwise direction with an operator's hand. It should be noted that the fitting slot 2b does not serve to positively hold the outer pawl 22 between a slantwise upward extending projection having no reference numeral allocated thereto and the bottom surface of the recess 2a with a high intensity of clamping force enough to immovably retain the outer pawl 22 in the fitting slot 2b but it suffices that all the outer pawls 22 are received in the recesses 2a with the aid of the retaining portion 3a of the retainer spring 3 and the fitting slots 2b without an occurrence of rattling movement of a housing of the lamp 20. It is recommendable that the fitting slots 2b and the slantwise upward extending projections are formed integral with the flange receiving portion 2 using a synthetic resin by employing an injection molding process. When a headlight 10 is fitted with a lamp 20 with the aid of the device 1, first, the left-hand end of each outer pawl 22 as seen in the anticlockwise direction in Fig. 3 is located in alignment with the left-hand end of each recess 2a, thereafter, three outer pawls 22 are placed on three recesses 2a from above, and subsequently, the lamp 20 is turned in the clockwise direction with an operator's hand so that one outer pawl 22 is firmly held between the bottom surface of the recess 2a and the retaining portion 3a of the retaining spring 3 in the clamped state, while the remaining two outer pawls 22 are firmly held in the fitting slots 2b in cooperation with the slantwise upward projections of the flange receiving portion 2. The turning movement of the lamp 20 is stopped when the right-hand end of the one outer pawl 22 comes in contact with the right-hand end of the recess 2a and the remaining two outer pawls 22 are firmly received in the fitting slots 2b. At this time, the lamp 20 is fitted to the headlight 10 at the correct position predetermined relative to the headlight 10. The second embodiment of the present invention has been described above with respect to the case that one retaining portion 3a is formed on the retainer spring 3. Alternatively, two or more retaining portions 3a may be formed on the retainer spring 3 as desired. It is recommendable that the number of retaining portions is adequately determined in consideration of the diameter of a wire material to be used for forming the retainer spring 3 and conveniences for a fitting operation to be performed for the lamp 20. In each of the aforementioned embodiments, a wire material such as a piano wire, a stainless steel wire or the like of which opposite ends are cut out is employed as a raw material. The present invention should not be limited only to a wire material having. Alternatively, a sheet of steel having excellent resiliency press-worked in conformity with the contour predetermined for the retainer spring 3 may be substituted for the wire material. While the present invention has been described above merely with respect to two preferred embodiments thereof, it should of course be understood that the present invention should not be limited only to this embodiment but various change or modification may be made without departure from the scope of the present invention as claimed by the appended claims.

Claims: Device (1) for fitting a headlight with a lamp (20) for a vehicle wherein said lamp (20) includes a bayonet flange (21) having a plurality of outer pawls (22) each radially projecting therefrom so as to allow said lamp (20) to be firmly held at the predetermined position turnably dislocated from the initial position thereof, comprising; a flange receiving portion (2) for receiving said bayonet flange (21) of said lamp (20) therein, a plurality of recesses (2a) formed on said flange receiving portion (2) for receiving said outer pawls (22) projecting radially outward of said bayonet flange (21) therein, each of said recesses (2a) being dimensioned to have a width larger than that of each other pawl (22) and the subtantially same depth as the thickness of each outer pawl (22), and a substantially circular retainer spring (3) made of a wire-shaped material having excellent resiliency and adapted to be firmly fastened to said flange receiving portion (2) by threadably fitting a plurality of screws (4) into the corresponding female-threaded holes formed in said flange portion and then tightening said screws (4), said substantially circular retainer spring (3) being dimensioned to have a diameter larger than the outer diameter of each outer pawl (22) but smaller than the outer diameter of said flange receiving portion (2), and moreover, having a plurality of substantially U-shaped retaining portions (3a) formed in the equally spaced relationship as seen in the circumferential direction of said flange receiving portion (2), each of said substantially U-shaped retaining portions (3a) being located at one of a left-hand half and a right-hand half of each recess (2a) so as to allow the corresponding outer pawl (22) to be firmly held between the bottom surface of said recess (2a) and said substantially circular retainer spring (3) in the clamped state when said lamp (20) is turned to said predetermined position from the initial position wherein said outer pawls (22) are initially received in said recesses (2a) formed on said flange receiving portion (2). The device according to claim 1, wherein each of said substantially U-shaped retaining portion (3a) is formed by inwardly bending said substantially circular retainer spring (3) and has a width equal to or less than the width of each outer pawl (22), the bottom side of each substantially U-shaped retaining portion (3a) being located outside of said lamp (20). The device according to claim 1, wherein each tightening screw (4) is located at the intermediate position between adjacent recesses (2a) formed on said flange receiving portion (2). The device according to claim 1, wherein said substantially circular retainer spring (3) is firmly tightened between the upper surface of said flange receiving portion (2) and the bottom of a head portion of each tightening screw (4). The device according to claim 1, wherein each outer pawl (22) is firmly held between the bottom surface of the corresponding recess and the corresponding retaining portion while the left-hand or right-hand end of said outer pawl comes in contact with the left-hand or right-hand end of the corresponding recess. Device (1) for fitting a headlight with a lamp for a vehicle wherein said lamp (20) includes a bayonet flange (21) having a plurality of outer pawls (22) each radially projecting therefrom so as to allow said lamp (20) to be firmly held at the predetermined position turnably dislocated from the initial position thereof, comprising; a flange receiving portion (2) for receiving said bayonet flange (21) of said lamp (20) therein, a plurality of recesses (2a) formed on said flange receiving portion (2) for receiving said outer pawls (22) radially projecting outward of said bayonet flange (21) therein, each of said recesses being dimensioned to have a width larger than that of each outer pawl (22) and the substantially same depth as the thickness of each outer pawl (22), a substantially circular retainer spring (3) made of a wire-shaped material having excellent resiliency and adapted to be firmly fastened to the flange receiving portion (2), said substantially circular retainer spring (3) being dimensioned to have a diameter larger than the outer diameter of outer pawl (22) but smaller than the outer diameter of said flange receiving portion (2), and moreover, having at least one substantially U-shaped retaining portion (3a) formed thereon, said substantially U-shaped retaining portion (3a) being located at either of a left-hand half or a right-hand half of the corresponding recess (2a) so as to allow the corresponding outer pawl (22) to be firmly held between the bottom surface of the corresponding recess (2a) and said substantially U-shaped retaining portion (3a) in the clamped state when said lamp (20) is turned to the predetermined position from the initial position where said outer pawls (22) are initially received in said recesses formed on said flange receiving portion (2), and a plurality of fitting slots (2b) each defined between a slantwise upward extending projection molded integral with said flange receiving portion (2) and the bottom surface of each of said recesses (2a) exclusive of one recess having said substantially U-shaped retaining portion (3a) placed thereon so as to enable the corresponding outer pawl (22) to be firmly held between the bottom surface of the corresponding recess (2a) and the corresponding slantwise upward extending projection in the clamped state when said lamp (20) is turned to the predetermined position from the intial position where said outer pawls (22) are initially received in said recesses (2a) formed on said flange receiving portion (2). The device according to claim 6, wherein said substantially U-shaped retaining portion (3a) is formed by inwardly bending a part of said substantially circular retainer spring (3) and has a width equal to or less than the width of the corresponding outer pawl (22), the bottom side of said substantially U-shaped retaining portion (3a) being located outside of said lamp (20). The device according to claim 6, wherein each fitting slit is formed on the operative side where each of said outer pawls (22) exclusive of one outer pawl having said substantially U-shaped retaining portion (3a) placed thereon is firmly held between the bottom surface of the corresponding recess (2a) and the corresponding slantwise upward extending projection while the left-hand or right-hand end of the corresponding outer pawl (22) is received in the corresponding fitting slit (26).

Inventors: FURUYA SHIGERU, KATO KOICHI, MATSUZAKI MAKIO, FURUYA, SHIGERU, KATO, KOICHI, MATSUZAKI, MAKIO
Applicants: STANLEY ELECTRIC CO LTD, STANLEY ELECTRIC CO., LTD.
Application year: 1993
Main classification: F21M7
IPC codes: F16B21, F21S8, F21V19