Electrical transmission or interconnection systems – Vehicle mounted systems – Automobile
Reexamination Certificate
1999-06-28
2001-05-22
Paladini, Albert W. (Department: 2836)
Electrical transmission or interconnection systems
Vehicle mounted systems
Automobile
C307S010300, C180S287000, C200S043080, C340S542000
Reexamination Certificate
active
06236121
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention pertains to a device with a key-actuatable lock cylinder and with a switching device, which, as a function of the rotation of the key, activates or deactivates certain electrical functions in a motor vehicle or the like, especially an ignition starter switch for a motor vehicle, where the lock cylinder consists of a stationary cylinder housing and a cylinder core, which is supported in the housing with freedom of rotation, which—starting from an original rotational position—is moved by the turning of the key into one of several defined working positions, in which the switching device initiates an electrical function in the motor vehicle or the like, which function is specific to the working position in question; where, in addition to tumblers for blocking the rotation of the cylinder core in the cylinder housing, a key channel to accept the key for unlocking the cylinder core is provided in the interior of the cylinder core; where permanent magnets are provided on the circumference of the cylinder core; and where, in addition to at least one locking channel for the tumblers, sensors responding to the permanent magnets of the cylinder core are also provided in the cylinder housing. The lock cylinder consists of a stationary cylinder housing and a cylinder core supported in the housing with freedom to rotate. The key can be inserted and removed from its key channel only in a certain original rotational position of the cylinder core. By turning the key, the cylinder core can be brought into certain defined rotational positions, which are to be referred in brief below as “working positions”. In these working positions, certain electrical functions in the motor vehicle or in some other useful object are activated or deactivated by way of the switching device.
2. Description of the Related Art
When a device such as this is used in motor vehicles, it serves as a so-called “ignition starter switch”. In the known device, the switching device has both a contact element which turns along with the turning of the key and stationary contacts, which are connected electrically to the given on-board electrical system. This device is located at the inner end of the lock cylinder. The movable switching element is connected in a torsionally rigid way to the cylinder core. In the working positions, the movable contact element becomes electrically connected to the stationary contact to which the system responsible for the desired function in the motor vehicle is connected. In the case of an ignition starter switch, there are usually three working positions besides the original rotational position. These include a first working position for switching on the electrical system of the vehicle, a second working position for releasing the internal combustion engine present in the vehicle for ignition, and a third working position for starting the engine.
The switching device in the known device occupies a considerable amount of space, and the space it occupies is then no longer available for other important components of the motor vehicle. In the known ignition starter switch, the switching device is installed at inner end of the lock cylinder. Thus the ignition starter switch is usually installed near the steering column of the motor vehicle, where it also has other duties to fulfill. These include the locking of the steering column after the key has been removed. Problems are encountered when the elements of the switching device are contacted mechanically. The angular distances between the working positions of the cylinder core initiating the various functions can be very small, for which reason the distances between the contacts in the switching device can be distinguished reliably only when a sufficient amount of space is available in the radial direction for the movement of the movable switching element from one angular position to the other. In addition, for safety reasons alone, a minimum amount of space must be provided for the switching device. All of this increases the space requirement.
There are locks (U.S. Pat. No. 5,186,031) in which a permanent magnet is installed on the circumference of the cylinder core. When the cylinder is turned by the key, an electronic monitoring function takes place by way of a sensor integrated into the cylinder housing; this sensor responds to the magnetic field of the cylinder core turning past it. As a result, the electrical system of the motor vehicle is turned on, and only then can the above-described switching device be activated. If the lock cylinder is forcibly torn out, electrical manipulations of the contacts are therefore useless. Unless the switching device is activated by way of the permanent magnet, which must be moved past the sensor, the switching device remains off-line. It therefore did not appear that there was any way to reduce the space requirement in the design of the known device.
In another device (U.S. Pat. No. 5,455,571), the attempt was made to make it more difficult for unauthorized persons to read the activation signal. This attempt took the form of a second sensor, which acts on the signal output of the addressed first sensor. The goal of this measure was to prevent outsiders from determining the signal value.
SUMMARY OF THE INVENTION
The invention is based on the task of developing a reliable device of the aforementioned kind which is simple and compact. This is accomplished in accordance with the invention by the following measures: the cylinder housing carries at least two sensors in zones which are axially offset from each other in the longitudinal direction, the sensor outputs of these sensors being connected to a common evaluator; in the corresponding axial zones, the cylinder core has several permanent magnets at the circumferential points which, in cooperation with the sensors, transmit to the sensor outputs an electrical coding which differentiates the original rotational position and the various working positions of the cylinder core; and the evaluator not only uniquely identifies the original rotational position and the working position of the cylinder core in question by way of the code but also—on the basis of the code which has been determined—initiates the electrical function in the motor vehicle or the like belonging to this working position.
The permanent magnets in the cylinder core cooperate with the sensors in the cylinder housing to encode all the defined working positions of the cylinder core. By way of the sensors, therefore, the specific working position of the cylinder core at the time in question can be uniquely identified, and this information can be sent to an evaluator, which then simultaneously acts as an electronic switch and initiates the individual electrical functions in the motor vehicle or other useful object. Whereas, in the state of the art, the rotational position is detected on the basis of an element of the switching device which moves along with the cylinder core, it is, in the invention, the job of the stationary sensors in the cylinder housing to identify the rotational positions. The code-controlled evaluator for the code-specific electrical functions is connected to the read-out points in the cylinder housing by signal lines of small diameter and can thus be installed at a point any desired distance away.
Because the components which bring about the desired electrical function are now electronic and no longer mechanical, it is also possible to produce the switching device in the device according to the invention in an extremely compact and inexpensive manner. The device according to the invention requires only that holes be provided in the cylinder housing to accept the sensors which read the code. The permanent magnets in the cylinder core can also be countersunk in holes at the points on the circumference which determine the coding. This means that, in the device according to the invention, the lock cylinder does not need to occupy any more space than it does in the state of the art, but also that the space at the inner
Kemmann Harald
Simon Jörg
Huf Hulsbeck & Furst GmbH & Co. KG
Kueffner Friedrich
Paladini Albert W.
LandOfFree
Device with a lock cylinder and a switching device for... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Device with a lock cylinder and a switching device for..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Device with a lock cylinder and a switching device for... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2495933