Antenna for motor vehicles

Abstract: The invention discloses an antenna (1) comprising a rod (2) connected to a supporting base (3) by means of a ball-and-socket joint (5) formed by a first ball-and-socket joint element (6) rigidly connected to said supporting base (3) by a second ball-and-socket joint element (7) connected to said rod (2). Said ball-and-socket joint elements revolvingly co-operating with each other in order to permit the orientation of said rod (2) of said antenna and are equipped with contrasting means (163, 173) suited to permit the fixing of said rod (2) in any of the orientation positions achieved.

Description: The invention concerns an antenna particularly suited to be applied on motor vehicles. It is a known fact that antennas for motor vehicles essentially consist of a base applied to the body of the car and supporting a rod which constitutes the active element of the antenna. In the embodiments belonging to the known technique, the rod of the antenna is fixed in relation to its supporting base and when it is mounted it positions itself with an inclination which depends on the construction shape of the supporting base and on the position which said base acquires when it is applied to the body of the car. It is understood that such embodiments entail a number of inconveniences. First, the impossibility of positioning the antenna at different inclinations prevents an optimum exploitation of the same, above all when said antenna is used with a double function both for the reception of radio broadcastings and for two-way transmissions by radiophone. Another inconvenience is also that the fixed antenna can be damaged by the impact against the rotating brushes of automatic carwashes. Document DE 27 08 594 discloses an antenna comprising a rod connected to a supporting base by means of a ball-and-socket joint comprising a first and a second element equipped with toothing arrangement. To change the orientation of the antenna the rod must be unscrewed to move away the second element in such a way the toothings.are not in contact. In such a way the antenna does not maintain any orientation if it is not supported by hand and it may be difficult to find the new desidered orientation. The present invention proposes to overcome such inconveniences. One purpose of the invention is to obtain an antenna particularly suited to be mounted cn motor vehicles, equipped with a rod adjustable in inclination in relation to the supporting base by means of which it is applied to the motor vehicle. It is another purpose that the rod of said antenna can be locked in any of the adjusting positions in which it can be arranged. It is another purpose that the antenna according to the invention presents theft-preventing characteristics such as to prevent the rod from being removed from its supporting base. Not the last purpose is that the connection of the rod of the antenna with its supporting base can be performed without using removable connecting means such as screws, locks, plugs and similar. The described purposes are reached by an antenna particularly suited to be mounted on motor vehicles which is in accordance with claim 1. According to one preferred embodiment, said first ball-and-socket joint element presents a body made of conductive material which is connected to said supporting base and equipped with a pair of rings co-axial with one another and placed at a distance from each other. Said second ball-and-socket joint element comprises an insulating reel having an essentially circular profile and presenting a seat wherein is inserted a conductive toothed element, the extremities of which protrude in relation to said insulating reel and co-operate with the inner surface of said co-axial rings of said first ball-and-socket joint element, said insulating reel being coupled by rotation within a housing having an essentially circular profile, obtained in said first ball-and-socket joint element in the area comprised between said co-axial rings. Said insulating reel and said conductive toothed element are connected to the rod of said antenna. When the orientation position is reached the rod is locked because of the reciprocal interference between the toothed elements, joined together and co-operating with one another, which belong to said co-axial rings of said first ball-and-socket joint element and to said conductive toothed element of said second ball-and-socket joint element. Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific example, while indicating a preferred embodiment of the invention, are given by way of illustration only, wherein: Fig. 1 shows the antenna according to the invention; Fig. 2 shows in an exploded representation the supporting base, the rod and the ball-and-socket joint which compose the antenna according to the invention represented in Fig. 1; Fig. 3 shows in an axonometric exploded representation the detail of the ball-and-socket joint represented in Fig. 2; Fig. 4 shows the front view of the ball-and-socket joint of Fig. 3 already assembled; Fig. 5 shows the ball-and-socket joint of Fig. 4 in a cutaway representation according to a vertical midplane, while it is being assembled to the rod of the antenna; Fig. 6 shows the ball-and-socket joint represented in Fig. 5 once the assembling with the rod has been completed; Fig. 7 shows the ball-and-socket joint of Fig. 6 with the rod applied to it, while it is being removed; Fig. 8 shows the ball-and-socket joint of Fig. 6 while the rod is being oriented; Fig. 9 shows the detail of the connection of the ball-and-socket joint to the base of the antenna; Fig. 10 shows a different embodiment of the ball-and-socket joint; As can be observed in Fig. 1, the antenna according to the invention, indicated as a whole with 1, comprises a rod 2 connected to a supporting base 3 applied to a supporting surface 4 consisting of the body of a car, for instance. Said rod 2 is connected to said supporting base 3 by means of a ball-and-socket joint, indicated as a whole with 5, visible in better detail in the exploded representations of Fig. 2 and Fig. 3, which is composed by a first ball-and-socket joint element 6, connected to the base 3, which co-operates with a second ball-and-socket joint element 7 connected to the rod 2. Said first ball-and-socket joint element 6 is applied to said base 3 through first connecting means which consist of an annular area 61 arranged at the extremity of the body 62 of said first ball-and-socket joint element 6, said area snap-coupling with a corresponding annular duct 31 visible in Fig. 9 and obtained in the base 3 of the antenna itself. Said first ball-and-socket joint element 6 is made of conductive material and presents a pair of rings 63 co-axial with one another and placed at a distance from each other, which are preferably obtained from a single block in the body 62 of the element itself, and a housing 64, having an essentially circular profile, being defined between said two rings. Said second ball-and-socket joint element 7 comprises, as can be observed in Fig. 3, an insulating reel 71 having an essentially circular profile, which presents a seat 72 within which, as can be observed in better detail in Fig. 4, is inserted a plate 73 made of conductive material . In particular, said seat 72 is defined inside said insulating reel 71 by the presence of a partition 74. Moreover, said insulating reel 71 has an axial length 571 equivalent to the axial distance 563 between the rings 63, so that said insulating reel 71 can be lodged in the housing 64 present between said rings 63. Said plate 73 belonging to said second ball-and-socket joint element 7 and said co-axial rings 63 belonging to said first ball-and-socket joint element 6 are equipped with contrasting means which comprise an outer toothing 173 obtained in said plate 73 and an inner toothing 163 obtained in each of said rings 63, wherein said toothings present profiles connected with one another and such as to be able to reciprocally co-operate whenever said first and second elements are joined together. It can be observed in particular in Fig. 3 that the plate 73 has an axial length 573 which is bigger than the axial length 571 of the insulating reel 71, so that when said plate 73 is lodged in the seat 72 of said insulating reel 71, once the latter has been inserted in the housing 64, its extremities 273 protruding from the reel 71 co-operate with the co-axial rings 63 by means of their corresponding toothings, as can be observed in Fig. 4. It can be also observed that said conductive toothed element 73 and said insulating reel 71 are equipped with second means for the connection to the rod 2 of the antenna which consist of a through hole 371 drilled in the body of said insulating reel 71 which positions itself co-axial with a corresponding threaded through hole 373 drilled in the body of said conductive toothed element 73. This latter hole is in turn co-axial with another unthreaded through hole 471 drilled in the partition 74 of the insulating reel 71, wherein said holes are all lined up one after the other. In particular, in the Figs. 3 and 4 it can be observed that said partition 74 also presents a slit 174 which communicates with its own said through hole 471 and which is suited to yield elasticity and flexibility to said partition in relation to the body of the insulating reel 71 to which it belongs. Said second connecting means of said second ball-and-socket joint element 7, couple with a terminal element, indicated as a whole with 21 belonging to the rod 2 of the antenna and which comprises an essentially cylindrical body, mostly developed following an axial direction, which presents a threaded area 123 obtained in correspondence with said rod 2 and an unthreaded area 124 having a reduced diameter, arranged on the continuity of said threaded area 123. Said terminal element 21 also presents at the extremity a conic terminal element 121 having a bigger diameter than said unthreaded area 124. The presence of such a terminal element 21 permits the connection of the rod 2 to the ball-and-socket joint element 5 whenever the threaded area 123 of said rod 2 couples with the corresponding threaded through hole 373 of the plate 73 and its unthreaded area 124 couples inside the through hole 471 drilled in the elastic partition 74 of the insulating reel 71. In Fig. 5 it can be observed that when coupled with said terminal element 21 with said ball-and-socket joint element 5, when said threaded area 123 is coupled with the threaded hole 373 of the metallic plate 73, the conic terminal element 121 forces against the hole 471 of the elastic partition 74 thus deforming the same, as represented in Fig. 5. When such a deformation reaches its highest value, the conic terminal element 121 penetrates into the hole 471 and the terminal element 21 couples its unthreaded area 124 inside the hole 471 itself, while the threaded area 123 is screwed in the threaded hole 373 until the rod 2 stops against the insulating reel 71, as can be observed in Fig. 6. When the rod 2 is coupled with the ball-and-socket joint element 5, the contact of the toothings 173 and 163 with one another permits a stick-slip rotation of the rod 2, as can be observed in Fig. 8, following any of the directions represented by the arrow 120 which are made possible by the rotation of the insulating reel 71 inside the housing 64 within which it is inserted. If it is necessary to lock the rod in any of the reached angular positions, it will suffice to tighten the rod 2 into the threaded hole 373 so as to force the metallic plate 73 against the co-axial rings 63, thus creating an interference between the respective toothings. Therefore, it can be noticed that the antenna according to the invention permits the orientation of the rod 2 in any of the directions shown in the plan of the drawing indicated by the arrow 120. Moreover, any reached position can be maintained because of the reciprocal interference of the toothings 163 and 173 present in the ball-and-socket joint element 5, by tightening the rod 2. This yields the advantage that the antenna can be pointed in the best position, whether it is used as an antenna for the reception of radio broadcastings or as an antenna for the two-way transmission by radiophone. It has already been said that another purpose of the invention proposes that the antenna can also present antitheft characteristics, such as to prevent the rod 2 from being removed from the supporting base 3 to which it is applied. For this purpose, Fig. 7 shows that if the rod 2 is unscrewed from the threaded through hole 373 within which it is coupled and then is lifted up following the vertical direction indicated by the arrow 221, the conic terminal element 121 stops against the elastic partition 74 which prevents the same from being removed and taken away. The partition 74, in fact, cannot be deformed following the direction 221 by the conic terminal element 121, since the presence of the conductive toothed element 73, which is rigid, prevents any deformation in such a direction. The hole 471, therefore, cannot be widened, consequently the conic terminal element 421 is prevented from passing and the rod 2 from being removed. Therefore, the antenna also presents antitheft characteristics. In Fig. 9, which represents the detail of the connection between said first ball-and-socket joint element 6 and the base of the antenna 3, it can be observed that the watertight seal in the area 21 which is below said first ball-and-socket joint element 6 and, therefore, in contact with the supporting surface 4 of the antenna, is ensured by the presence of a gasket 131, preferably of the OR type, which is lodged inside an annular groove 161 obtained in the body 62 of said second ball-and-socket joint element 6. A different embodiment of the ball-and-socket joint element of the antenna is represented in Fig. 10, wherein it can be observed that said ball-and-socket joint 50 presents said second ball-and-socket joint element, indicated as a whole with 60, wherein the insulating reel 710 is equipped with an elastic partition 740 which, instead of being obtained in a single piece with the body of the reel 710, is added to it since it is lodged inside guides 741 obtained in the body of the reel itself which receive said elastic partition 740. According to what has been said, it is understood that the antenna according to the invention achieves all the proposed purposes. During the manufacturing process the antenna may undergo some modifications concerning its shape, its length, its dimensions in general. The shape and dimensions of the ball-and-socket joint which connects the rod to its base may change, as may the shape and dimensions of the contrasting elements of the elements which compose the ball-and-socket joint. In particular, with regard to the elements which compose the ball-and-socket joint, these may acquire any shape which, rather than being essentially cylindrical as has been described, it can be spheric so as to permit the orientation of the rod of the antenna in space rather than on the surface.

Claims: An antenna (1) comprising a rod (2) connected to a supporting base (3) applied to a surface (4) supporting the antenna, by means of a ball-and-socket joint (5) which is formed by a first ball-and-socket joint element (6) rigidly connected to said supporting base (3) by means of first connecting means (61) and by a second ball-and-socket joint element (7) connected to said rod (2) by means of second connecting means (371, 373, 471), said ball-and-socket joint elements (6, 7) being provided with toothed means (163, 173) suited to permit the orientation of said rod (2), characterized in that said rod (2) cooperates with an elastic partition (74) belonging to said second ball-and socket joint element (7), said elastic partition (74) being suited to elastically deform when the rod is pressed against it. An antenna (1) according to claim 1, characterized in that said first ball-and-socket joint element (6) presents a body (62) made of conductive material wherein, on one side there is a pair of rings (63) co-axial with one another and placed at a distance from each other and, on the opposite side, there are first means (61) for the connection of said first ball-and-socket joint element (6) to said base (3) of said antenna (1) and that said second ball-and-socket joint element (7) comprises an insulating reel (71) having an essentially circular profile, presenting a seat (72) wherein is inserted a conductive toothed element (73) resting on said elastic partition (74), the extremities (273) of which axially protrude in relation to said insulating reel (71) and co-operate with the inner toothed surface (163) of said co-axial rings (63) of said first ball-and-socket joint element (6). An antenna (1) according to claim 1, characterized in that said insulating reel (71) is revolvingly coupled with a housing (64) having an essentially circular profile, obtained in said first ball-and-socket joint element (6) in the area comprised between said co-axial rings (63), said insulating reel (71) and said conductive toothed element (73) being equipped with said second means (371, 373, 471) for the connection to said rod (2) of said antenna (1). An antenna (1) according to claim 1 or 2, characterized in that said partition (74) is made elastic by at least one through slit obtained in the partition (74) itself and communicating with a through hole (471) drilled in said partition (74). An antenna (1) according to claim 3, characterized in that said elastic partition (74) is obtained in a single piece with said insulating reel 71. An antenua (1) according to claim 3, characterized in that said elastic partition (740) is applied to said insulating reel (60) through a couple of inside guides (741) obtained in the insulating reel (60). An antenna (1) according to claim 2, characterized in that, the body (62) of said first ball-and-socket joint element (6) has an essentially cylindrical shape and is equipped with said first connecting means for the connection to said base (3) of said antenna (1) consisting of an annular area (61), having a bigger diameter than the diameter of the body (62) and obtained at the extremity of said body (62), which snap-couples with a corresponding annular duct (31) obtained in said base (3) of said antenna (1). An antenna (1) according to claim 2, characterized in that, said second means for the connection of said second ball-and-socket joint element to said rod of said antenna, comprise a threaded through hole (373) drilled in the body of said conductive toothed element (73) and an unthreaded through hole (471), co-axial with said threaded through hole (373) and obtained in said elastic partition (74) present inside said insulating reel (71) and which defines said seat (72) wherein said conductive toothed element (73) is inserted, said through holes (373, 471) being suited to lodge the coupling of a terminal element (21), belonging to said rod (2) of said antenna (1) and made of conductive material, which is inserted into another through hole (371) obtained in the body of said insulating reel (71). An antenna (1) according to claim 8, characterized in that said terminal element (21) comprises an essentially cylindrical body, mostly developed following an axial direction, which presents a threaded area (123) obtained in correspondence with said rod (2) of said antenna (1), an unthreaded area (124) having a smaller diameter than said threaded area (123), arranged on the continuity of said threaded area (123) and a conic terminal element (121) having a bigger diameter than said unthreaded area (124) and arranged on the continuity of the latter, said unthreaded area (124) being suited to lodge the thickness of said elastic partition (74) of said insulating reel (71), whenever said threaded area (123) couples with said threaded through hole (373) of said conductive toothed element (73) and said conic element (121) elastically deforms said elastic partition (74) in order to penetrate inside said unthreaded hole (471) of said elastic partition (74), the presence of said conductive toothed element (73) preventing the deformation of the same elastic partition (74) following a direction which is opposite to the direction of the previous deformation, so as to prevent said terminal element (21) from separating from said second ball-and-socket joint element (2). An antenna (1) according to claim 2, characterized in that, the body (62) of said first ball-and-socket joint element (6) externally presents an annular groove (161) suited to lodge a sealing gasket (131) which cooperates by interference with said supporting base (3), wherein said body (62) of said first ball-and-socket joint element (6) is coupled.

Inventors: CALEARO MASSIMO, CALEARO, MASSIMO
Applicants: CALEARO MASSIMO, CALEARO, MASSIMO
Application year: 1995
Main classification: H01Q1
IPC codes: H01Q1