Push-button contactor for activating call signals in push-button panels

Abstract

 A push-button contactor for activating call signals in push-button panels, particularly for intercommunication and video-communication systems, comprises a housing having a body to which are fastened a first blade and a second blade, both made of an electroconductive material, projecting within the housing, and provided with respective contact pins engageable and solderable in respective holes of the printed circuit for connecting to desired electroconductive tracks. The contactor comprises an actuator stud, slidable in guide means made on said housing and provided with a cam-shaped surface cooperating with a corresponding surface of the first blade in order to elastically draw it against the second blade, from a rest position to a work position. The contactor also comprises elastic bias means, for withdrawing said stud from its work position to its rest position, reacting against a push-button which axially engages the stud.

Description

[0001] The present invention relates to a push-button contactor for activating call signals in push-button panels, particularly for intercommunication and video-communication systems.

[0002] The above-mentioned push-button panels, which may be either in one piece or made of a number of modules, comprise a frame in which are housed electric and/or electronic components, as well as a predetermined number of call push-buttons provided with respective name-bearing labels and/or other functional components, such as electroacoustic transducers, cameras, and the like. Particularly, the known contactors are fastened to the frame or modules at predetermined positions, depending on their number and on the arrangement preferred for the user (in columns, in rows, etc.), and they are provided with clamps or screws for fastening leads to a printed circuit.

[0003] The above wires, which in push-button panels for buildings with many flats may comprise a large amount of cables, are a hindrance in maintenance and repair operations, as well as during label replacement, for which it is necessary to access the inside parts of the housing.

[0004] Moreover, the arrangement and orientation of the contactors, together with the hindrance caused by the wire, often restrict use of tester probes or similar devices, as necessary for checking electric contacts.

[0005] Furthermore, in poor lighting conditions, it is convenient to improve the visibility of the push-buttons by providing them with a luminous effect. However, the small size of such known contactors as well as the surrounding narrow spaces, as required to reduce overall size, often makes it difficult to house light sources inside the contactors.

[0006] Therefore, a main object of the present invention is to provide a push-button contactor for activating call signals on outdoor panels of intercommunication and video-communication systems, which overcomes the above-mentioned drawbacks of known contactors, and, more particularly, which can be adjusted in relation to different arrangements of the printed circuit without requiring any connection wire with the printed circuit.

[0007] Another object of the invention is to provide a push-button contactor whose contacts can be easily checked without need for difficult or inconvenient disassembly.

[0008] A further object of the invention is to provide a push-button contactor provided with a low-cost lighting system which is adjustable to different mutual arrangements of the printed circuit and contactor.

[0009] Another object of the invention is to provide a push-button contactor whose cost is comparable to the known ones, and which can be manufactured by known processes and equipment.

[0010] The above-mentioned objects and advantages of the invention, as well as other objects such as will appear from the following description, are achieved by a push-button contactor having the features recited in claim 1. The remaining claims state other advantageous features of the invention.

[0011] This invention will be now described in more detail, with reference to the attached drawings, shown by way of non limiting example, wherein:

Fig. 1 is a perspective, exploded view of a push-button contactor according to this invention;

Fig. 2 is a perspective view of the internal components of the push-button contactor;

Fig. 3 is a front view of the push-button contactor;

Fig. 4 is a longitudinal cross-section of the push-button contactor, made along line IV-IV of Fig. 3;

Fig. 5 is a perspective, exploded view of a second embodiment of the push-button contactor, achieving same aims and employing the same inventive skill;

Fig. 6 is a perspective view of the second embodiment of the push-button contactor;

Fig. 7 is a front view of the second embodiment of the push-button contactor;

Fig. 8 is a longitudinal cross-section of the second embodiment of the push-button contactor, made along line VIII-VIII of Fig. 7.

[0012] With reference to Figs. 1 to 4, a push-button contactor 10 comprises a housing consisting of a body 11 adapted to be supported on a printed circuit (not shown), and a cover 12 which is removably fastenable to body 11, preferably by snap-connection means. A first blade 14 and a second blade 15, made of an electroconductive material and projecting into the housing, are fastened to body 11 and are provided with respective pins 16, 17 insertable and solderable in respective holes in the printed circuit in order to connect to desired electroconductive tracks. An actuator stud 18 is slidable in holes 19, 20 made on respective opposite walls of the housing and acting as guide means for the opposite ends of the stud. The stud has a cam-shaped surface cooperating with a corresponding surface of first blade 14, in order to elastically draw it against second blade 15, from a rest position to a work position. For this purpose, the first blade 14 has a V-shaped hump 22 is adapted to cooperate like a cam with an axial, intermediate span of stud 18 having two coaxial, truncated-cone-shaped swellings 23, 24 defining a seat for V-shaped hump 22. Moreover, a helical bias spring 25 acts to withdraw stud 18 from its work position to its rest position, by reacting against a push-button 26, having guide wings such as 50 and in axial engagement with stud 18. To this purpose, helical spring 25 is fitted on the end portion of stud 18 opposite to push-button 26, between the rim of one of the holes, hole 19 in the example, and the annular surface 27 at the base of truncated-cone-shaped swelling 23. Stud 18 has a third truncated-cone-shaped swelling 24, whose smaller, annular base 36 engages the rim of hole 20. At least one centering pin 34 projecting from body 11 engages a corresponding slot made on the printed circuit.

[0013] Advantageously, tabs 28, 29 projecting from respective blades 14, 15 outwardly from the housing can be contacted by instruments for checking the performance of the contactor.

[0014] Preferably, stud 18 is made of a translucid material and a light-emitting diode 30, which is connected to a power supply unit (not shown), is arranged substantially parallel with the axis of the stud, in a seat 49 made on body 11 near stud 18. Accordingly, the beams generated by the LED penetrate the translucid stud and, since the refractive index of the material of the stud is higher than the refractive index of the air, they are conveyed into, and longitudinally traverse, the stud. Diode 30 could be also shared among a number of adjacent studs. A translucid channel 51, facing the corresponding end of stud 18, is made in push-button 26. Thus, when channel 51 is traversed by the beam, a luminous effect visible from outside is generated.

[0015] Figs. 5 to 8 show a second embodiment of the push-button contactor, achieving the same objects and falling within the same inventive concept. This embodiment is similar to the former and, accordingly, like parts, which have the same reference number increased by 100, will not be further described unless necessary. The push-button contactor 110 of this second embodiment has a push-button 126 having guide wings such as 150. Push-button 126 is integral with an axial end of stud 118, and is slidable in a guide hole 120. The opposite axial end 141 is adapted to cooperate with V-shaped hump 22 of first blade 114, in order to elastically draw it against second blade 15, similarly to what has been described above. In this second embodiment, blade 114 also acts as an elastic bias means, in contrast to the first embodiment where this function was performed by spring 25. The entire stud/push-button unit may be made translucid, or the push-button might be made partially opaque and provided with a channel for passage of beam.

[0016] As persons skilled in the art will appreciate, the stud can be inserted within the housing in either direction while maintaining its operability. This allows a considerable flexibility of arrangement of the printed circuit inside the push-button panel, so that the printed circuit can be fastened with any of its main sides facing the front part of the push-button panel, depending on requirements of appearance or size.

[0017] It can be seen that the push-button contactor according to the invention achieves the stated object, in that it does not require any connection wires to the printed circuit but rather is directly attachable to it, while allowing flexibility in its arrangement.

[0018] Another advantage of this contactor is that its contacts can be easily checked by means of tabs 28, 29, projecting outwardly from the housing and shaped to facilitate the insertion of tester probes, or similar devices.

[0019] A further advantage of the contactor according to the invention is that it is provided with an unexpensive illumination system, which is adjustable to different mutual arrangements of the printed circuit with respect to the contactor. Moreover, and which has an overall cost comparable with known contactors, while being manufacturable by processes and equipment usually available in the field.

[0020] In practice, materials and sizes can be different from what has been shown, depending on requirements.

Claims

1. A push-button contactor for activating call signals in push-button panels, particularly for intercommunication and video-communication systems, characterized in that it comprises:

- a housing having a body to which are fastened a first blade and a second blade, both made of an electroconductive material, projecting within the housing, and provided with respective contact pins engageable and solderable in respective holes of the printed circuit for connecting to desired electroconductive tracks; and

- an actuator stud, slidable in guide means made on said housing and provided with a cam-shaped surface cooperating with a corresponding surface of the first blade, in order to elastically draw it against second blade, from a rest position to a work position; and

- elastic bias means, biasing said stud from its work position to its rest position and acting against a push-button which axially engages the stud.

2. The push-button contactor of claim 1, characterized in that said first blade has a V-shaped hump with which said stud cooperates.

3. The push-button contactor of claim 2, characterized in that an axial, intermediate span of said stud has two coaxial, truncated-cone-shaped swellings delimiting a seat for said V-shaped hump and having a cam-like cooperation with it.

4. The push-button contactor of anyone of the preceding claims, characterized in that said guide means consist of two holes made on respective opposite walls of the housing and lodging the end portions of the stud.

5. The push-button contactor of anyone of the preceding claims, characterized in that said elastic bias means comprise a helical spring fitted on the end portion of the stud opposite to the push-button, between the rim of one of said holes and the annular surface at the base of one of said truncated-cone-shaped swellings.

6. The push-button contactor of claim 2, characterized in that said push-button is integral with an axial end of said stud.

7. The push-button contactor of claim 6, characterized in that the end portion of the stud opposite to the push-button is adapted to cooperate as a cam with the V-shaped hump.

8. The push-button contactor of anyone of the preceding claims, characterized in that said housing comprises a body for laying on the printed circuit, and a cap which is removably attached to said body.

9. The push-button contactor of anyone of the preceding claims, characterized in the blades have respective tabs projecting outwardly from the housing, for contact with instruments for checking the performance of the contactor.

10. The push-button contactor of anyone of the preceding claims, characterized in that said stud is made of a translucid material and said contactor comprises lighting means for generating a light beam traversing the stud.

11. The push-button contactor of anyone of the preceding claims, characterized in that said lighting means comprise a light-emitting diode connected to a power supply unit and arranged substantially parallel with the axis of the stud in a seat made on said body near the stud.

12. The push-button contactor of anyone of substantially claims, characterized in that a translucid channel is made through said push-button, facing the corresponding end of said stud in order to allow the passage of said light beam.

Drawing