US3541481A

US3541481A - Automatic electric switch

Info

Publication number: US3541481A
Application number: US754058A
Authority: US
Inventors: Karl-Heinz Scheibel
Original assignee: Siemens AG
Current assignee: Siemens AG
Priority date: 1967-08-23
Filing date: 1968-08-20
Publication date: 1970-11-17
Anticipated expiration: 1987-11-17
Also published as: DE1588755A1; FR1578505A; AT284243B; DE1588755B2; CH479157A

Description

KARLHEINZ SCHEIBEL 3,541,4B AUTOMATIC ELECTRIC SWITCH Nov. l

5 Shoets-Shoqfl Filed 2.20.; 1968 X a 1 W 3 r I l I l 1970 KARL-HEINZ SCHEIBEL AUTOMATIC ELECTRIC SWITCH I Filed Au 20,1968

2 cit:

2h 19 Fig. 3

Fig. 4

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17, 1970 KARL-HEINZ SCHEIBEL ,Eflfllfii AUTOMATIC ELECTRIC SWITCH Filed Aug. 20, 1968' 3 Sheets-Sheet 3 Fig. 7

United States Patent U.S. Cl. 335-11 6 Claims ABSTRACT OF THE DISCLOSURE Automatic switch assembled of modular units includes a switch base portion having a switch shaft carrying movable contact portions, and a modular component including a rapid trip device carrying a fixed contact portion, said fixed contact portion, in assembled condition of the switch, being engageable with said movable contact portion.

My invention relates to automatic electric switch and particularly to such switches which are assembled from modular units wherein there is provided a switch base portion including a switch shaft having movable contact members, and a modular unit including a rapid trip or release device and, if necessary, an overcurrent trip or release device or circuit breaker. In a switch of the aforementioned type, the fixed contact members are secured through terminal bar on the switch base portion. After the modular unit is attached in this known construction, the terminal bars secured to the switch base portion are screwed to a terminal bar projecting out of the modular unit. The movable contact members are connected through separate leads to the terminal binding posts of the switch in this known device. The modular unit can only be joined with the switch base portion in one direction in this heretofore known device because a plunger must be passed through an opening in the switch base portion to open or separate the contacts.

These known switches have a relatively costly construction and have moreover several resistances to transmission due to the screw connections thereof, which adversely aifect the flow of current in the switch.

It is accordingly an object of my invention to provide automatic electric switch which avoids the foregoing disadvantages of the heretofore known device of this type and which particularly reduces the relatively costly construction and transmission resistance thereof.

With the foregoing and other objects in view, I accordingly provide automatic electric switch wherein the fixed contact member is secured to the modular unit and, when the modular unit is installed in the switch, the fixed contact member is brought into contact with a movable contact of the switch.

In accordance with another feature of my invention which makes best use of the available space at lowest cost for materials, I provide the switch with a rapid trip or release device having a thrust armature for breaking or separating the contacts. A plunger of the armature extends through fixed contact member outside of the contact point proper and acts as member which strikes the movable contact member and thereby separates it from the fixed contact member. It is thereby further possible to install the modular unit from any desired side on the switch base portion without having to be concerned with extending the plunger through an opening in the switch base portion. A simple construction of partitions or separating walls between the poles of the switch is provided when the fixed contact members are provided on both sides with ribs formed on the switch base position.

According to another feature of the invention which 'ice also affords relatively good space utilization for the switch, I provide the overcurrent trip or release devices in the modular unit, which are disposed offset from the row of terminals coordinated or associated with the pole of the switch and opposite to the rapid trip or release devices so that an adjusting device for overcurrent trip or release devices is capable of being built-in laterally of the overcurrent trip or release devices within the width of the switch predetermined by the rapid trip or release devices. Separate bearing locations for the switch shaft in the switch can be dispensed with on the adjusting device when bearing pins for the movable contact members serve for conducting the current through the movable contact members and the rotary mounting of the switch shaft. Moreover, no additional transmission resistances produced by threaded connections are present. In addition, a weld or rivet connection between the terminal strap and movable contact members can also be dispensed with. Since the movable contact member is pressed with the force of the contact compression spring against the bearing pins, there is thereby afforded a more reliable current transmission. A simplified construction of the holder for the bearing pins is afforded by the fact that the bearing pins are held by terminal straps fixed to the switch base portion.

It is moreover advantageous in accordance with the invention to provide a holder for each bearing pin comprising two ears of the terminal straps bent parallel to one another and formed with holes for receiving the bearing pins therein.

Other features which are considered as characteristic for the invention are set forth in the appended claims.

Although the invention is illustrated and described herein as embodied in automatic electric switch, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.

The construction of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

FIG. 1 is a side elevational view partly broken away and partly schematic of the switch constructed in accordance with my invention;

FIG. 2 is a top plan view of FIG. 1;

FIG. 3 is a front elevational view of part of the switch of FIG. 1, showing the modular unit of the invention which includes the rapid trip device, the overcurrent trip device and the fixed contact member;

FIG. 4 is a top plan view of FIG. 3;

FIG. 5 is a top plan view partly in cross section of a part of the switch of FIG. 1, showing the holder for the switch shaft in the switch base portion;

FIG. 6 is an elevational view of a terminal strap for holding the movable contact member forming part of the structure shown in FIG. 5;

FIG. 6a is a longitudinal diagrammatic view of the screw for securing the terminal strap of FIG. 6 to a wall of the switch base portion shown in FIG. 5;

FIG. 7 is an elevational view of a movable contact member forming part of the switch as shown in FIG. 1;

FIG, 8 is a view of the switch shaft as shown in FIG. 5 with the associated elements, such as the movable contact members, removed therefrom; and

FIG. 9 is an end view of FIG. 8.

Similar members are identified in all of the figures with the same reference numerals.

Referring now to the drawings, there is shown a switch base portion 1 provided with a switch shaft 2, in which movable contact portions 3 are mounted, and terminal straps 4. A quenching device is disposed above the movable contact portions 3. A modular unit 6 includes therewithin a switch lock which is actuable by a manual crossbar 7. A strap 8 provides a connection between the switch lock 6 and an arm 9 of the switch shaft 2. As is seen in FIG. 2, the illustrated embodiment is that of a threepole automatic switch. A modulator unit 10, which is fastened to the switch portion 1 has a construction shown in greater detail in FIGS. 3 and 4. Terminal straps 11 are provided for the modular unit 1 and are electrically connected to bimetal strips 12, which serve as an overcurrent trip or release or circuit breaker, the bimetal strips for their part conducting current through coils 13 of the rapid trip or release 14, A fixed contact portion 15 of the automatic switch is mounted outside the modular unit 10, the other end of the coil 13 being connected to the fixed contact portion 15. A plunger 16 of the armature 17 of the rapid trip or release device 14 passes through the fixed contact portion 15 and comes into contact with the movable contact portion 3 when the rapid trip device 14 is actuated, as can be seen from FIG. 1. The movable contact portion 3, which is forced against the fixed contact portion 15 by the biasing action of a spring 18 that abuts the switch shaft 2, is thereby displaced in a direction opposing the biasing force of the spring 18 and the

contacts

3 and 15 are thereby broken or opened. With this construction, the fixed contact portion 15 can be kept relatively short and small and need not have a U-shaped bend. The end of the rapid trip device 17 opposite the plunger 16 is provided with a projection 19 that engages a latching lever 20 which actuates the switch lock of the modulator unit 6 through the intermediary of suitable non-illustrated and conventional transmission means, such as linkages, gears, etc.

As shown in FIG. 4, the bimetal strips 12 are located offset from the fixed contact portions 15 and also from the rapid trip devices 14 so that an adjusting device 21 for the bimetal trip device can be placed near the bimetal strips 12 without thereby widening the switch. A further simplification of the switch construction and therewith also a reduction of the space required for the switch is afforded by the fact that the switch shaft 2 is rotatably mounted by means of pins 22 (FIG. 5) on the terminal straps 4 which are fastened by screws 34 to a wall of the switch base portion 1. The terminal straps 4 are furnished therefor with ears 24 that are bent so that they are parallel to one another and are furthermore respectively formed with per forations for receiving the pins 22 therethrough. Intermediate the end pins 22 by which the switch shaft 2 is rotatably mounted there is provided a pin 23 which, with the pins 22, is employed additionally for rotatably mounting the movable contact portions 3 respectively. For this purpose, the movable contact portion 3 has an extension 26 which is provided with a bore 27 and, in the illustrated embodiment, is also formed of cars that are bent parallel to one another. In order to be able to bring the terminal straps 4 or the bent ears 24 into engagement with the switch shaft 2 by means of the mounting pins 22, cutouts or

recesses

28 and 29 are provided in the switch shaft 2. After the bent cars 24 and the extensions 26 of the movable contact portions 3 are inserted in the recesses 28, the mounting pins 22 are inserted into the openings or recesses 29 of the switch shaft 2 and, in the inserted condition thereof, engage in blind bores 30 formed therein.

One end of the spring 18 abuts a cam 31 on the arm 32 of the switch shaft 2, and the other end of the spring 18 abuts the movable contact portion 3. When the switch is open, the contact portion 3 egages an arm-shaped projection 33 of the switch shaft 2.

I claim:

1. Automatic switch assembled of modular units comprising a switch base portion including a switch shaft, bearing pins carried on said switch base portion for rotatably mounting said switch shaft and movable contact members pivotally mounted on said bearing pins, said bearing pins being current-conductive and forming with said movable contact members a current supply path through the switch base portion, and a modular unit carrying fixed contact members, said fixed contact members in assembled condition of the switch being engageable with said movable contact members.

2. Automatic switch according to claim 1, wherein said modular unit includes a plurality of rapid trip devices, each device comprising a thrust armature having a plunger extending through a respective fixed contact member outside the point of contact engagement thereof with a respective movable contact member, said plunger being capable of being thrust against said movable contact member at a location thereof between said point of contact engagement and a respective bearing pin for breaking contact engagement of said fixed and movable contact members.

3. Automatic switch according to claim 1, wherein said modular unit is formed with ribs flanking said fixed contact members.

4. Automatic switch according to claim 1, including a plurality of overcurrent trip devices and an adjusting device for said overcurrent trip devices forming part of said modular units, said overcurrent trip devices being located offset with respect to a row of terminals coordinated thereby with a pole of the switch and located opposite a plurality of rapid trip devices, said adjusting device being built-in laterally of said overcurrent trip devices within the width of the automatic switch determined by said rapid trip devices.

5. Automatic switch according to claim 1, including terminal straps on said switch base portion for holding said bearing pins.

6. Automatic switch according to claim 5, wherein said bearing pins are held in two ears of said terminal straps bent parallel to one another and formed with holes for receiving said bearing pins therein.

References Cited UNITED STATES PATENTS 1,960,402 5/1934 Wilckens 335-11 2,134,593 10/1938 Wulsten 335-9 BERNARD A. GILHEANY, Primary Examiner H. BROOME, Assistant Examiner UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. Dated November 1970 KARL-HEINZ SCHEIBEL Inventofls) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In the heading the German priority number should read as fo1lows:-P 15 88 755.5

; F-EC B231971 EAL mm E. 50mm,

mm Fletch, 1-,, Commissioner of Pater Aflcating Officer