US3539737A

US3539737A - Electric switch

Info

Publication number: US3539737A
Application number: US771015A
Authority: US
Inventors: Karl Schupp
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 1967-11-14
Filing date: 1968-10-28
Publication date: 1970-11-10
Anticipated expiration: 1987-11-10
Also published as: DE1615817B2; GB1242420A; DE1615817A1; DE1615817C3; FR1580630A

Description

Nov. 10, 1970 K. scHuPP 3,539,737

ELECTRIC SWITCH Filed Oct. 28, 1968 2 Sheets-Sheet 1 FIG] 30 INVENTOR Karl SCHUPP his ATTORNEY NOV. 10, 1970 K. SCHUPP 3,539,737

ELECTRIC swm'un Filed Oct. 28, 1968 2 Sheets-Sheet 2 INVEHTOP Kori ECHUF'F his ATTORNEY United States Patent O US. Cl. 20011 14 Claims ABSTRACT OF THE DISCLOSURE An ignition switch wherein the key can move a rotor, which carries the movable switch contact, unidirectionally from an 01f position through an ignition position to a start position and wherein a spring biases the rotor from start position back to ignition position. Repeated movement of the rotor from ignition position to start position is prevented by a two-armed lever which is actuated by a pair of cams on the rotor whereby one of the cams cooperates with a leaf spring to move the lever to blocking position when the rotor is moved from ignition position to start position and the other cam cooperates with the leaf spring to move the lever to unblocking position when the rotor is returned from ignition position to off position. The rotor is thereupon free to again move from the off position through the ignition position and to the start position. In this way, the lever prevents actuation of the starter when the engine is running.

BACKGROUND OF THE INVENTION The present invention relates to improvements in electric switches, particularly to improvements in ignition switches for use in automotive vehicles or the like. Still more particularly, the invention relates to improvements in ignition switches wherein the movement of that rotary part which carries one or more movable switch contacts from ignition position to start position is blocked when the engine is running.

It is already known to provide an ignition switch with a rotor which carries one or more movable switch contacts and wherein the rotor cannot be turned in a direction to operate the starter once it is moved from start" position back to ignition position. In such conventional ignition switches, the rotor carries a single cam which engages a blocking member in response to rotation of the rotor in either direction (see, for example, German Utility Model No. 1, 932,285). A drawback of such switches is that the extent of angular displacement of the rotor without operating the starter is limited because the extent of such angular displacement depends on the size or bulk of the blocking member. The blocking member cannot be enlarged indiscriminately because the ignition switch should not occupy too much room in a vehicle.

SUMMARY OF THE INVENTION One of the objects of my invention is to provide a simple, compact and relatively inexpensive electric switch which can be used to control the ignition system of an automotive vehicle and wherein the rotor can turn from its ignition position, without operating the starter, within a relatively large angle and without necessitating an increase in the size of the switch.

Another object of the invention is to provide a simple, rugged, compact and easy-to-install blocking device for the key-operated rotor of an ignition switch for automotive vehicles.

A further object of the invention is to provide a novel rotor for use in the ignition switch.

3,539,737 Patented Nov. 10, 1970 ICE The improved electric switch comprises a rotary switching member (hereinafter called rotor for short) which is movable unidirectionally from a first to a second and thereupon to a third angular position and from the third back to the second and first positions, and blocking means for preventing repeated movement of the rotor from second to third position after the rotor returns from third to second position. The blocking means preferably comprises a substantially kidney-shaped two-armed lever which is pivotable between blocking and unblocking positions in which it respectively prevents and permits movement of the rotor from second to third position.

The rotor comprises first actuating means (preferably a cam) for effecting movement of the blocking means from blocking to unblocking position in response to movement of the rotor from second back to first position, and second actuating means (preferably comprising a substantially tooth-shaped second cam) for effecting movement of the blocking means toward blocking position in response to movement of the rotor from second to third position. Such movement of the blocking means to blocking position may be completed in response to return movement of the rotor from third to second position. The completion of movement of blocking means to blocking position and the completion of movement of blocking means to unblocking position can be brought about by a resilient detent, for example, a suitable leaf spring, which permanently biases the blocking means to one or both positions.

The housing in which the rotor turns may be provided with notches and the rotor may comprise a spring-biased detent which enters one of the notches in the first and second positions of the rotor. A torsion spring or analogous biasing means is preferably provided to urge the rotor from third position back to second position. The first, second, and third positions of the rotor are the off, ignition and start positions of the rotor when the latter forms part of an ignition switch for automotive vehicles.

The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved electric switch, itself, however, both as to its construction and its mode of operation, together with additional features and advantages thereof, will be best understood upon perusal of the following detailed description of a specific embodiment with reference to the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a sectional view of an electric ignition switch which embodies the invention, the section being taken along the line 1-1 of FIG. 4;

FIG. 2 is an enlaregd perspective view of the rotor in the switch of FIG. 1;

FIG. 3 is a perspective view of the blocking member;

FIG. 4 is an end elevational view of the switch, with certain parts removed, the rotor being illustrated in zero position;

FIG. 5 illustrates the structure of FIG. 4, with the rotor shown in a first on or ignition position.

FIG. 6 shows the structure of FIG. 4 or 5, with the rotor in a second on or start position; and

FIG. 7 illustrates the structure of FIG. 4, 5 or 6, with the rotor blocked in the first on position against movement to the second on position.

DESCRIPTION OF THE PREFERRED EMBODIMENT The electric ignition switch of FIG. 1 comprises a circular base plate 10 which consists of insulating material and carries a pair of pin-shaped terminals 11 which are anchored therein. The outer end portions 11a of terminals 11 constitute connectors which can be coupled to leads 11c, only one shown. The inner end portions 11b of the terminals 11 constitute fixed contacts and can be engaged by or disengaged from a plate-like movable contact 12. The base plate 10 is centered in a cup-shaped housing 13 and is fixedly secured thereto. A turnable switching memher or rotor 14 is turnably mounted in the housing 13 and is provided with a keyhole or socket 14A for a key, not shown. The outer end portion 14A of the rotor 14 is accommodated in a sleeve-like portion 15 of the housing 13 and the inner end portion 14b of the rotor is journalled in a centrally located recess 16 of the base plate 10. The exact configuration of the rotor 14 is best shown in FIG. 2. This rotor comprises a radially extending arm 14B which is formed with a blind bore for a helical spring 18a which biases a spherical detent 18 adapted to enter one of several notches 17 provided therefor in the internal surface of the housing 13.

The movable contact 12 rotates with but is movable axially of the rotor 14. A spring 30 biases the contact 12 in a direction toward the fixed contacts 11b. The rotor 14 cooperates with a blocking member 20 which is biased by a resilient detent here shown as a leaf spring 19 and is pivotable between two positions. The pivot pin 21 for the blocking member 20 is mounted in or forms part of the housing 13; the axis of this pin is parallel to the axis of the rotor 14.

The blocking member 20 resembles a substantially kidney-shaped two-armed lever, one arm of which cooperates with the aforementioned resilient detent 19 and is provided with an axially extending projection 23 which can cooperate with a first actuating cam 22 of the rotor 14. The arrangement is such that a portion of the projection 23 extends into the plane in which the actuating cam 22 rotates. The other arm of the blocking member 20 has a less pronounced axially extending second projection 24 whose height as seen in the axial direction of the blocking member 20 (see FIG. 3) approximates half the height of the projection 23. The second projection 24 merges into the projection 23 and extends into the path of movement of a second actuating cam 25 on the rotor 14. The cam 25 forms part of a disk-shaped portion 140 of the rotor 14, and this disk-shaped portion 140 has a tooth 26 provided with a substantially radially extending flank and with an arcuate outer flank. The radial flank of the tooth 26 can be engaged by the tip of the projection 24 in blocking position of the member 20. The projection 24 is adjacent to one axial end and extends substantially radially beyond the peripheral surface of the disk-shaped portion 140. It is referred to produce the

parts

14, 20 and 13 as castings.

The operation:

When the ignition system is off, the rotor 1 is held in a zero or o position shown in FIG. 4. The spherical detent 18 of the arm 14B then extends into that notch 17 of the housing 13 which registers with the 0 graduation shown in FIG. 4. Such graduation may but need not be provided on the dashboard of the vehicle which embodies the ignition switch.

When the user decides to move the rotor 14 and the movable contact 12 to the first on position or ignition" position Z (shown in FIG. the disk-shaped portion 140 of the rotor moves over the flat part of the blocking member 20 whereby the actuating cam 25 slides along the

projections

24 and 23. The cam 22 travels along the end face of the projection 24 and toward engagement with the projection 23. The spherical detent 18 then enters another notch 17 of the housing 13, namely, that notch which is adjacent to the symbol Z in FIG. 5. The manner in which the switch causes one or more lamps to light up and to activate the fuel gauge and/or other instruments in a vehicle is well known from the art.

In order to start the engine, the operator moves the rotor 14 (by way of the key which has been inserted into the hole 14A) to the second on or start positions shown in FIG. 6. Such turning of the rotor 14 is carried out against the opposition of a return spring 27 which is preferably a torsion spring. It will be noted that, when the rotor 14 assumes the start position shown in FIG. 6, the spherical detent 18 does not enter a notch 17 so that the spring 27 is free to turn the rotor back toward the ignition position of FIG. 5 as soon as the key is released by the operators hand. In response to movement of the rotor 14 from the position of FIG. 5 toward that shown in FIG. 6, the cam 22 of the rotor engages the projection 23 of the blocking member 20 and turns the latter against the opposition of the resilient detent 19 until the projection 24 reaches and abuts against the arcuate outer flank of the tooth 26. The key is released as soon as the engine is started and the spring 27 is then free to return the rotor 14 to the position shown in FIG. 7. The resilient detent 19 is free to effect further clockwise pivotal movement of the blocking member 20 (compare FIGS. 6 and 7) whereby the projection 24 of the blocking member moves against the radial flank of the tooth 26 and prevents repeated turning of the rotor 14 to the start position of FIG. 6. Such start position can be reached again by first moving the rotor 14 from the position shown in FIG. 7 back to the off position shown in FIG. 4 whereby the cam 25 pivots the projection 24 of the blocking member 20 in a counterclockwise direction so that the resilient detent 19 first yields and thereupon compels the blocking member to turn in a counterclockwise direction until the latter reassumes the unblocking position shown in FIG. 4. If the user thereupon desires, the key can be rotated again in a direction to move the rotor 14 first to the ignition position of FIG. 5 and thereupon to the start position of FIG. 6. In this way, the operator cannot operate the starter when the engine is running. On the other hand, and if the engine is stopped with the rotor 14 in the blocked position shown in FIG. 7, all the user has to do to restart the engine to turn the rotor from the position of FIG. 7 back to the off position of FIG. 4, and to thereupon turn the rotor through the ignition position of FIG. 5 to the start position of FIG. 6. When the engine is restarted and the key is released, the rotor 14 returns to the blocked position shown in FIG. 7.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features which fairly constltute essential characteristics of the generic and specific aspects of my contributions to the art.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims:

1. In an electric switch, particularly an ignition switch for use in automotive vehicles, a combination compris mg a rotor movable unidirectionally from a first to a second and thereupon to a third angular position and from said third back to said second position; blocking means for preventing repeated movement of said rotor from said second to said third position, said blocking means being movable between blocking and unblocking postions in which it respecitvely prevents and permits movement of said rotor from said second to said third position and said rotor comprises first actuating means for effecting movement of said blocking means from blocking to unblocking position in response to movement of said rotor from second to first position and second actuating means axially displaced from said first actuating means for effecting movement of said blockmg means to blocking position in response to movement of said rotor from second to third position; and resilient means for biassing said blocking means to at least one of said positions thereof.

2. A combination as defined in claim 1, wherein said rotor comprises a flank and said blocking means comprises a portion which engages said flank in response to movement of said rotor from third back to second position to thereby prevent return movement of said rotor directly from said second to said third position thereof.

3. A combination as defined in claim 1, wherein said actuating means are cams.

4. A combination as defined in claim 1, wherein said rotor further comprises a disk-shaped portion and wherein said first actuating means is a cam provided on said disk-shaped portion.

5. A combination as defined in claim 4, wherein said disk-shaped portion further comprises a tooth having a substantially radially extending flank and said blocking means comprises a portion which engages said flank in response to movement of said rotor from said third back to said second position thereof to thereby prevent repeated angular movement of said rotor from second to third position.

6. A combination as defined in claim 4, wherein said second actuating means comprises a second cam which is adjacent to one axial end of said disk-shaped portion and extends radially beyond the periphery of said diskshaped portion.

7. A combination as defined in claim 1, wherein said blocking means comprises a two-armed lever which is pivotable between said blocking and unblocking positions thereof, one arm of said lever comprising a first axially extending projection which is engaged by said second actuating means to thereby pivot said lever toward blocking position in response to movement of said rotor from said second toward said third position thereof, the other arm of said lever comprising a second axially extending projection which is engaged by said first actuating means to move said lever toward unblocking position in response to movement of said rotor from said second back to said first position thereof.

8. A combination as defined in claim 7, wherein one of said projections extends in the axial direction of said lever beyond the other of said projections.

9. A combination as defined in claim 1, wherein said blocking means comprises a substantially kidney-shaped two-armed lever.

10. A combination as defined in claim 9, wherein said lever comprises two projections one of which is engaged by said second actuating means in response to movement of said rotor from second toward third position and the other of which is engaged by said first actuating means in response to movement of said rotor from said second back toward said first position thereof, one of said projections extending axially of said lever beyond the other projection and said other projection merging into said one projection.

11. In an electric switch, particularly in an ignition switch for use in automotive vehicles, a combination comprising a rotor movable unidirectionally from a first to a second and thereupon to a third angular position and from said third back to said second position; blocking means for preventing repeated movement of said rotor from said second position to said third position, said blocking means being movable between blocking and unblocking positions in which it respectively prevents and permits movement of said rotor from second to third position and said rotor comprises first actuating means for effecting movement of said blocking means from blocking to unblocking position in response to movement of said rotor from second to first position and second actuating means axially displaced from said first actuating means for effecting movement of said blocking means to blocking position in response to movement of said rotor from second to third position; and resilient detent means arranged to effect final movement of said blocking means to blocking position in response to movement of said rotor from third back to said second position.

12. In an electric switch, particularly in an ignition switch for use in automotive vehicles, a combination comprising a rotor movable unidirectionally from a first to a second position and thereupon to a third angular position and from said third back to said second position; and blocking means for preventing repeated movement of said rotor from said second position to said third position, said blocking means being movable between blocking and unblocking positions in which it respectively prevents and permits movement of said rotor from second to third position and said rotor comprises first actuating means for effecting movement of said blocking means from blocking to unblocking position in response to movement of said rotor from second to first position and second actuating means axially displaced from said first actuating means for effecting movement of said blocking means to blocking position in response to movement of said rotor from second to third position, said blocking means comprising two projections one of which being engaged by said second actuating means during movement of said rotor from second to third position and the other of which being engaged by said first actuating means during movement of said rotor from second back to said first position thereof.

13. A combination as defined in claim 12, wherein the length of one of said projections exceeds the length of the other projection and wherein each of said projections extends into the path of rotary movement of the respective actuating means.

14. In an electric switch, particularly in an ignition switch for use in automotive vehicles, a combination comprising a rotor movable unidirectionally from a first to a second and thereupon to a third angular position and from said third back to said second position; blocking means for preventing repeated movement of said rotor from said second position to said third position, said blocking means being movable between blocking and unblocking positions in which it respectively prevents and permits movement of said rotor from second to third position and said rotor comprises first actuating means for effecting movement of said blocking means from blocking to unblocking position in response to movement of said rotor from second to first position and second actuating means axially displaced from said first actuating means for effecting movement of said blocking means to blocking position in response to movement of said rotor from second to third position; and detent means for yieldably holding said rotor in each of said first and second positions thereof.

References Cited UNITED STATES PATENTS 2,121,671 6/1938 Schwarze 200-44 2,715,661 8/1955 Miller 200-11 2,778,891 1/1957 Jacobi 200-11 2,868,906 1/1959 Soreng 200-44 3,172,968 3/ 1965 Arendt 200-44 ROBERT K. SCHAEFER, Primary Examiner I. R. SCOTT, Assistant Examiner U.S. Cl. X.R. 20044