DE1076228B - Electrical switch, especially limit switch - Google Patents

Description

The invention relates to an electrical switch, in particular a limit switch with a side Slidable plungers which are arranged next to the contact points and carry the switch cams in an adjustable manner. It a switch of this type is known in which the switching cams on the plunger by means of an elongated hole and screw are adjustable. This setting is very complicated, relatively crude and requires a great sensitivity.

There are also electrical switches began in which the entire switch insert with several contacts is adjusted at the same time, so that a single adjustment of the contact points is not possible. In addition, the type of contact can never be changed with these switches. So he won't let himself switch from a normally open contact to an opener.

Finally, electrical switches are known at which the switching cams are arranged movably on a shaft only in their axial direction and in their Longitudinal shift switch the permanently set contact in order to interrupt the connection. the Switching points are determined and are located on the outer pipe, which is provided with an external thread thus fixed for actuation by the switching cams.

The invention provides an electrical switch, in particular a limit switch, in which a exact determination of the switching point is possible and the setting is made by hand without any aids can be. This is achieved according to the invention in that the plunger with an over a plurality of contact points continuous thread, in particular fine thread, for axial adjustment is provided by screwable arranged on it, ring-shaped switching cams and means are provided for their determination. This screwing type of adjustment of the Switching means can adjust the switching cams very precisely and above, in particular by means of a fine thread also take place individually for each contact point, so that the switching point can be selected as desired. According to a further invention, the cam rings are to be fixed on the tappet by means of latching means, for example by balls under the action of a spring, which snap into place in grooves, the snap-in balls are expediently arranged in the cam rings and the locking grooves in the tappet.

In the drawing, the invention is in one embodiment shown.

Fig. 1 shows the limit switch in a perspective view at an angle from above;

Figure 2 is a cross-section through a pad;

Fig. 3 shows the switch in a side view, partially in section;

Fig. 4 is a perspective view of a cap-type electrical switch,
especially limit switches

Applicant:

KA Schmersal & Co.,
Wuppertal-Barmen, Lenneper Str. 37-41

Karl-Heinz Buss, Wuppertal-Barmen,
has been named as the inventor

rarely limit switch with actuator when removed Lid;

Fig. 5 shows a perspective view of an encapsulated switch with snap-action switching attachment.
The switch shown consists of four cells 1 or chambers of small depth, the profile of each cell from Fig. 2 can be seen. A switch can consist of two or any desired plurality of such cells or chambers, all of which are completely identical to one another.

Each cell is connected to a fixed contact 2 2 'provided. The fixed contacts of two cells each form a contact point. All cells are 1 lined up on two bolts 3 and 4, the bolt 4 forming the fulcrum of a contact lever 5. The con-

clock lever5 is movable at its end with a mounted contact bridge 8 provided. This contact bridge 8 is made of a flat solid silver part formed, which is pressed against two of the fixed contacts 2 by a torsion spring 6.

The contact lever 5 is provided with a roller 9, which lies in the path of cam rings 10, which on a cylindrical plunger 7 are arranged. The plunger 7 is continuous with one over its entire length Thread 7 'on which the cam

kenringe 10 are screwed so that they can be adjusted in the axial direction. Any cam ring 10 is adjusted in the axial direction that it rotates for itself and thus in the desired setting is brought.

In order to be able to fix the cam rings 10 in the desired setting, they are with under the effect provided by springs 20 standing snap-in balls 21. These balls 21 cooperate with locking grooves 22, running on the plunger 7 in the axial direction

909 757/382

are arranged. In that a plurality of such latching grooves are provided on the circumference of the plunger and the thread is designed as a metric fine thread, an extremely fine adjustment and -Adjustment of the cam rings can be made.

The plunger 7 is hollow and is provided with a return spring 12 in its interior. In his inner, upper part it is provided with a trailing spring, which in a known manner after full utilization of the switching path still allows the plunger to run in the axial direction. The plunger 7 we4 of the reciprocating parts of the machine actuated to which it is attached, and displaced in this way in the axial direction. Move thereby -the cam rings 10 with in the axial direction and release the contacts according to their setting the end.

Each cell is provided with a transparent window 11, which on the one hand the switch room against large Protects dirt and at the same time makes the contact visible from the front. Also, the connections are easily accessible from the front. The plunger 7 is at the top at the more stressed point with a Plastic part 14, in particular, made of polyamide and mounted at the bottom in a pressed material cover plate 15.

Fig. S shows an encapsulated version of the Switch a snap circuit 16 is provided. This snap action is to be used in the usual way abrupt movement of the contacts can be achieved. This solution has the advantage that any an-order of contacts can be provided with snap action. ---

The actuator 17 (Fig. 4) can also be provided on the housing without a snap action. The lever 18 is designed as a clamping lever and kaiin in any angular position to the housing 19 be attached. The actuator 17 contains the bearing and seal for the shaft of the crank 18. The switch is actuated with the lever, whereby the one that triggers the actuation of the switch moves Part of the machine can move at an angle to the direction of movement of the ram.

Claims (10)

Patent claims: .1. Electric switch, in particular limit switch, with a displaceable plunger which is arranged laterally next to the contact points and carries the switching cams in an adjustable manner, characterized in that the plunger (7) has a thread (T) _1, in particular a fine thread, extending over a plurality of contact points, for axial adjustment is provided by ring-shaped switching cams (10) screwed on it, and means are provided for fixing them. 2. Switch according to claim 1, characterized in that the detection of the cam rings (10) on the plunger (7) by locking means, for example by balls under the action of a spring (21), which snap into grooves (22), the snap-in balls (21) in the cam rings (10) and the latching grooves (22) are arranged in the plunger (7). 3. Switch according to claim 1 and 2, characterized in that the cam rings (10) consist of one tough and wear-resistant plastic such as polyamide. 4. Switch according to one of the preceding claims, characterized in that it is in itself known way from individual, the contacts (2) with connections (2 ') carrying, on bolts (3, 4) cells (1) which can be lined up one after the other. 5. Switch according to claim 1, characterized in that the cam rings (10) with below Spring action standing contact levers (5) interact and the contact levers (5) are pivotable are mounted around one of the alignment bolts (4). 6. Switch according to claim 4, characterized in that every two cells (1) have a contact point wear with double interruption. 7. Switch according to one of claims 1 to 6, characterized in that the contact lever (5) Movable contact bridges (8) made of flat material and are attached with forced separation. 8. Switch according to one of claims 1 to 7, characterized in that each contact lever is expediently provided with a roller (9), which in the path of the cam rings lies. 9. Switch according to claim 1 to 8, characterized in that the plunger (7) is hollow and equipped with a return and overtravel spring . - see is .... 10. Switch according to claim 1 to 9, characterized in that that he has a resolution with a special, known jump system (16) which means that the switch can be used in any ■ contact setting " can be operated in momentary switching. .. ".'.- .. ■ Considered publications; German patents. No. 899 061, 592 075; ■ -German Auslegeschriften M 17350 VIIIb / 21 c (published on the 27th of 9th 1956), M 27334 VIIIb / 21 e (published on July 19, 1956); German utility model No.-1 734 683 v, 29.11. 1956; British Patent Nos. 546 791, 553 480; -'- U.S. Patents No. 2,319,503, 2,774,836, 550,792. : For this! Sheet of drawings © 90Ϊ 757 / 3S2 2.60