Slide switch

Abstract: A slide switch comprises a terminal base (3), a terminal groove (17) extending in the sliding direction of a movable contact (10), and a terminal (30) inserted into the terminal groove and fixed on a rear side by caulking. The terminal base has a coupler portion (20) on a rear side thereof and a coupler terminal (34) formed on an end of a terminal (30) projects into the coupler portion via a through hole. On a surface of the terminal base opposite from the coupler portion (20), a spacer (8) having a smooth sliding face is mounted substantially flush with the contact portion (31) whereby rising of the terminal is prevented.

Description: This invention relates to a slide switch of the type in which a movable contact slides on a stationary contact fixed on a terminal base. Such a slide switch is known for example from the document EP-A-0 678 883. Another slide switch is known which comprises a slider which is freely slidable in a designated direction and carries a movable contact, a terminal base provided with a stationary contact relative to which the movable contact slides, a coupler on a rear face and a terminal having an end portion forming a coupler terminal projecting into the coupler, and another portion forming the stationary contact, the switch being molded by injection molding so that a terminal is integral with the terminal base. Such integrated molding of a terminal and a terminal base requires a great deal of time. A terminal has to be set into a molding die while molding, and because when an end portion of a terminal is so positioned, this causes unevenness on the surface of the terminal base, durability of the movable contact is reduced as a result of it sliding thereon. Moreover, because there is a possibility that the stationary contact is displaced or deformed by the injection pressure, it is necessary to enough leave spaces between the stationary contacts when a plurality of stationary contacts are used. This increases the size of the terminal base, so that design freedom is reduced. According to the present invention there is provided a slide switch comprising: a slider freely slidable in a predetermined direction and having a movable contact; a terminal base extending in the sliding direction of the slider, a surface thereof being a sliding face for the slider and a coupler portion being provided at an end region of a rear face thereof; a terminal, a part of which is exposed on a surface of the terminal base to form a stationary contact on which the movable contact slides, and provided with a coupler terminal projecting into the said coupler portion; and a terminal groove formed in a surface of the terminal base into which the said terminal is fitted, the terminal being secured at the rear of the terminal base by caulking after the terminal has been inserted into the terminal groove, and characterised in that a spacer is attached to the terminal base to cover a part of the said terminal superposed on the said coupler portion as viewed from the surface of the terminal base, so that the movable contact can slide on the spacer. The said spacer may have a smooth surface and be generally flush with the stationary contact. Since a terminal is inserted into a terminal groove formed in a previously molded terminal base from a surface side, and is fixed by caulking on a rear side of the terminal base, it does not require so much time for positioning as a conventional insert molding. Further, because it is not necessary to guard against slipping off or deforming in a molding, it becomes possible to miniaturize the terminal base and design freedom is enhanced. Also, since a spacer is attached to the terminal base to cover an upper part of a coupler portion, a coupler terminal is prevented from rising to a surface of the terminal base when connected with an external power supply connector, and a movable terminal can slide on the spacer. Therefore, since unevenness on a sliding face of the movable contact is reduced, durability of the movable contact can be improved. An embodiment of the invention will now be described by way of example and with reference to the accompanying drawings, in which:- Fig. 1 is a view illustrating the mounting of a spacer on a terminal base; Fig. 2 is a plan view of the slide switch; Fig. 3 is a rear view thereof; Fig. 4 is a sectional view taken along line 4-4 of Fig. 2; Fig. 5 is a sectional view taken along line 5-5 of Fig. 2; Fig. 6 is a sectional view taken along line 6-6 of Fig. 2; Fig. 7 is a sectional view taken along line 7-7 of Fig. 2; Fig. 8 is a plan view of the surface of the terminal base; Fig. 9 is a plan view of the terminal base with a spacer removed; and Fig. 10 is a sectional view taken along line 10-10 of Fig. 9. Referring to the drawings, a slide switch is of generally oblong shape in plan view and comprises a cover 1, a slider 2 and a terminal base 3. The cover 3 is made from resin, an elongate slide hole 4 is formed in a surface thereof, and the slider 2 is supported by a shift lever 5 so as to be freely slidable in the longitudinal direction in the slide hole 4. The cover 1 is generally box-shaped and is open on the bottom side thereof, into which the terminal base 3 is fitted. Holes 6 in the side walls of the cover receive claws 7 projecting from side faces of the terminal base 3, to secure the base and the cover together (see Fig. 6). Part of the surface of the terminal base 3 is covered by a spacer 8. In the center region of the slider 2 a transversely elongate hole 10 is formed to allow movement of the lever 5 (see Fig. 2). As is apparent from Fig. 5, a first movable contact 11 is given contact pressure by a first contact spring 12 engaging the rear side thereof. A second movable contact 13 is given contact pressure by a second contact spring 14. Between the first movable contact 11 and the second movable contact 13, a guide projection 15 is formed which is slidably received in a guide groove 16 which extends lengthwise in a center region of the terminal base 3, to guide the movement of the slider 2 (see Figs. 4, 8 and 9 ) . As is shown in Fig. 9, the terminal base 3 is a generally box-shaped resin-made elongate body, corresponding to the cover 1. The top surface thereof forms a sliding surface for the slider 2. A plurality of terminal grooves 17 are formed therein, extending in the sliding direction of the slider 2. Each terminal groove 17 is open to the surface of the terminal base 3. A bottom portion of the terminal groove 17 communicates with a mounting hole 19 which extends lengthwise of the groove and penetrates the bottom wall of the terminal base 3 (see Fig. 3). There are a number of holes 19, but only some of then are referenced. On the top face of the terminal base 3, recesses 18 are formed to accommodate later described contact portions of the terminals (see Fig. 10), and in a corner region of the bottom face of the terminal base a projecting coupler portion 20 is integrally formed. A plurality of terminal grooves 21 are formed inside the coupler portion 20, penetrating the terminal base. Moreover, on the face of the terminal base 3 to which the spacer 8 is attached, a pair of positioning grooves 22 are formed (see Fig. 9), and a pair of engaging projections 23a and 23b are also provided to hold the spacer (see Fig. 5). As is apparent from Fig. 5, the spacer 8 is a resin-made plate-like member. On its rear face are two parallel positioning projections 24 which fit into the positioning grooves 22 and which also engage with a deepened recess 22a by way of a projection 24a (see the enlarged view in Fig. 10). On one of the longer sides of the spacer 8, a U-shaped guide rail 25 engages with a projection 23a. On the other longer side a guide rail 26 engages under a projection 23b. A surface of the spacer 8 is a smoothed face. The spacer 8 is accommodated in a recess 27 in the terminal base 3, flush with a surface of the terminal base 3 (see Fig. 9) . Referring to Fig. 9, a terminal 30 comprises a contact portion 31 of plate-like form, a terminal groove inserting portion 32 bent at right angles to the contact portion 31 and inserted into the terminal groove 17, a bent portion 33 folded at right angles on an upper position of the coupler portion 20 at an end portion of the terminal groove inserting portion 32, and a coupler terminal 34 having its tip bent downward at right angles to the bent portion 33. However, terminals 35a, 35b, 35c, 35d, 36 and 37, which are attached below the guide groove 16 of the terminal base 3, are not provided with such contact portions 31, and a part of an end face of the terminal groove inserting portion 32 is arranged to make sliding contact with the surface of the terminal base 3. Parts other than the projecting portions of the terminal groove inserting portions 32 are retracted deeply into the terminal groove 17, as shown in Fig. 9. Referring to Fig. 8, the terminal groove inserting portions 32 of the terminals 30, 35a, 35b, 35c, 36 and 37 are respectively inserted in corresponding terminal grooves 17. The contact portions 31 are embedded in the recesses 18 and the tip ends of the coupler terminals 34 project into the coupler portion 20, while the coupler terminals 34 are inserted into the terminal grooves 21 (see Figs. 6 and 10). Fixing legs 38 (Fig. 3) formed on a lower portion of the terminal groove inserting portion 32 project towards the rear side of the terminal base 3 through the mounting holes 19 which penetrate on a bottom portion of the terminal groove 17, and each of terminals 30, 35a, 35b, 35d, 36 and 37 is integrated with the terminal base 3 by fixing the projecting portions, by caulking, from the rear side of the terminal base 3. Reference 39 in Figs. 8 and 9 is a projection to make the second movable contact 13 capable of moving smoothly without being caught, and is flush with a face 41 (the highest surface) of the terminal base 3, arranged to form a periphery of a recess 40 accommodating the terminal mounted in the guide groove 16. In Figs. 8 and 9, a part which is flush with the face 41 in the surface of the terminal base 3 is shown as a dotted face. References 42 and 43 indicate positioning projections for mounting the cover 1 on the terminal base 3. Thus the terminals 30, 35a, 35b, 35c, 35d and 37 are not molded integrally after being inserted into the terminal base 3, but after molding of the terminal base they are inserted into the terminal groove 17 and fixed by caulking on the rear side of the terminal base. Therefore, because a great deal of time is not required for positioning preparatory to insert molding, as is conventional, the terminals 30, 35a, 35b, 35c, 35d, 36 and 37 can be easily fixed and no consideration need be given to position divergence or deformation while molding. Thus miniaturization of the terminal base 3 becomes possible and design freedom is enhanced. Moreover, because a part of the bending portion 33 is covered by the spacer 8, when an external power supply connector is connect to the coupler terminal 34, rising of the bending portion 33 is prevented. Further, since the surface of the spacer 8 is smooth and plate-like, unevenness on the sliding face for the first movable contact 11 is less, so that the durability of the movable contact 11 is improved. Also, because the first movable contact 11 slides on the spacer 8 flush with the other contact portions 31, unevenness of the whole sliding area is lessened and durability of the movable contact 11 is further improved. Furthermore, because the terminals 30, 35a, 35b, 35c, 35d and 36 are fixed by caulking, the surface of the terminal base 3 is pressure-contacted to a caulking jig and the exposed surface of the terminal base 3 and each of terminals 30, 35a, 35b, 35c, 35d and 36 are formed substantially flush with each other, so that unevenness of the sliding face can be reduced.

Claims: A slide switch comprising: a slider (2) freely slidable in a predetermined direction and having a movable contact (11,13); a terminal base (3) extending in the sliding direction of the slider, a surface thereof being a sliding face for the slider and a coupler portion (20) being provided at an end region of a rear face thereof; a terminal (30), a part of which is exposed on a surface of the terminal base to form a stationary contact on which the movable contact slides, and provided with a coupler terminal (34) projecting into the said coupler portion; and a terminal groove (17) formed in a surface of the terminal base into which the said terminal is fitted, the terminal being secured at the rear of the terminal base by caulking after the terminal has been inserted into the terminal groove, and characterised in that a spacer (8) is attached to the terminal base to cover a part of the said terminal superposed on the said coupler portion as viewed from the surface of the terminal base, so that the movable contact can slide on the spacer. A slide switch according to claim 1, wherein the said spacer (8) has a smooth surface and is generally flush with the said stationary contact.

Inventors: OIKAWA HIROSHI, OIKAWA, HIROSHI
Applicants: TOYO DENSO KK, TOYODENSO KABUSHIKI KAISHA
Application year: 1998
Main classification: H01H15
IPC codes: H01H11, H01H1, H01H15