GB2319803A

GB2319803A - Key with two-part handle

Info

Publication number: GB2319803A
Application number: GB9725295A
Authority: GB
Inventors: Henryk Frenzel; Josef Kraiczyk
Original assignee: Siemens AG
Current assignee: Siemens AG
Priority date: 1996-11-29
Filing date: 1997-11-28
Publication date: 1998-06-03
Also published as: FR2756584A1; GB9725295D0; FR2756584B1; DE19649688A1

Abstract

A key (1) has a handle (3) and a shaft (4). The handle (3) comprises two handle parts (5, 6) which are releasably locked with each other. When a large force (F 1 ) acts on the handle (3) the second handle part (6) is released from the first handle part (5) without destruction. In this way injuries to the driver's knees in the event of an accident are avoided or at least reduced.

Description

2319803 KEY The invention relates to a key and, in particular, to a key

for the operation of a steering wheel lock or ignition lock of a motor vehicle. Such keys have a key handle to which a key shaft, possibly with a mechanical coding, is fastened.

In a key known from EP 0 658 670 Al, the key shaft is locked into place in the key handle. If the key is an ignition key of a motor vehicle which is in the ignition lock, there is danger that the driver's knee will knock against the key handle during a rear end collision, causing the handle of the key to break off from the key shaft. The key shaft then remains in the lock. Usually the handle can no longer be attached to the shaft because parts of the handle, upon impact with the handle, are destroyed. The shaft on its own in the ignition lock without the key handle cannot be turned or can only be turned with very great expenditure of force.

The invention therefore seeks to provide a key which reduces the danger of injuries and with which, even when there is no key handle, operation of the lock is still possible.

According to the invention, there is provided a key, comprising a key handle having two handle parts which are releasably locked with each other, whereby the first handle part is fastened to a key shaft and the second handle part is releasable from the first handle part when a force which is greater than a specified force acts on the key handle.

Thus, the key handle has two handle parts which are releasably locked with each other. The first hand le part is securely connected to the key shaft. The second handle part is released from the first handle part without destruction when a greater force (knee impact or impact with a part of the body) acts on is the handle.

Advantageous developments of the invention are set out in the subclaims.

It is particularly advantageous if a transponder is arranged in the first handle part, by means of which transponder an immobilizer of the motor vehicle can be released. After a hard impact against the handle, the first handle part remains connected to the shaft and so the immobilizer can still be released. In the second handle part a transmitting unit can be arranged, by means of which, upon the operation of a button, a coded signal is wirelessly transmitted to lock or unlock the lock.

The two handle parts can also have predetermined breaking points at which the handle parts break when a predetermined force acting an the handle is exceeded. This likewise reduces the consequences of an impact with a part of the body against the handle. The predetermined breaking points are arranged in such a way that after a part of the handle parts has broken off, a part of the handle still remains so that a turning of the key in the lock is still possible.

For a better understanding of the present invention, and to show how it may be brought into effect, reference will now be made, by way of example, to the accompanying drawings, in which:

Figure 1 shows a plan view of a key in accordance with the invention.

Figure 2 shows a section through the key according to line II-II in Figure 1.

Figure 3 shows a plan view of another exemplary embodiment of a key.

Figure 4 shows a plan view of a further exemplary embodiment of a key.

Figure 5 shows a section through the key according to line V-V in Figure 4.

is Figure 6 shows a plan view of a key, the handle parts of which are separated from each other.

As shown in Figure 1, a key 1, in particular for the operation of a steering wheel lock or ignition lock 2 of a motor vehicle, has a key handle (called handle 3 in the following), to which a key shaft (called shaft 4 in the following) is fastened. The handle 3 has two handle parts 5, 6 which are releasably locked with each other.

The first handle part 5 is securely connected to the shaft 4. The second handle part 6 is releasably connected to the first handle part 5 as can be seen more clearly in Figure 2. The second handle part 6 is only released from the first handle part 5 if a relatively great force F, (characterized by the arrow in Figure 1) acts on the handle 3. Buttons 7 are arranged on the second handle part 6, and coded signals are wirelessly transmitted by a transmitting unit 8 shown in Figure 2 when the buttons 7 are operated.

The second handle part 6 has an upper part 9 and a lower part 10 which are secured to each other. The transmitting unit 8 and possibly a transmitting and receiving unit 11 are arranged in a cavity between the upper part 9 and the lower part 10. These units are represented diagrammatically in Figure 2 by components such as batteries and circuit holders.

When buttons 7 are operated the transmitting unit 8 generates and transmits coded signals, in order to unlock or to lock one or more locks. Other devices, for example internal lighting of a motor vehicle, garage doors, garden lighting, lighting of a building etc., can also be remotecontrolled by the transmitting unit 8.

The transmitting and receiving unit 11 (also called transponder ill in the following) receives a signal and thereupon automatically transmits a coded is signal back. With such a transponder ill it is possible, for example, to release an immobilizer of a motor vehicle if the key 1 is in the ignition lock 2.

As soon as the key 1 is turned in the ignition lock 2 the ignition switch is closed. Thereupon, by way of a transmitter, not shown, data coded in the ignition lock 2 and/or power is transmitted to the transponder 111. Subsequently, the transponder 111 answers automatically with its userspecific or vehicle-specific code signal, by means of which is proved its entitlement to start the motor vehicle and drive it. The data and/or power transmission takes place inductively by means of coils 12, 13 as transmitting and receiving aerials, with the range of the signals being only very limited.

Both the first handle part 5 and the second handle part 6 have one or more stop connections 15 (also called snap connections), whereby the two handle parts 5, 6 are locked with each other. The stop connections 15 are in this respect constructed in such a way that they are released from each other without destruction when a specified force FN is exceeded.

A stop connection 15 comprises in each case a locking hook 16 which is locked into place in a latch 17 of the respective other part of the stop connection 15. If the first handle part 5 has a locking hook 16, the second handle part 6 has a latch 17, and vice versa. In this way the two handle parts 5, 6 are joined together to form the handle 3 and are releasably fastened to each other.

If the key 1 is used as an ignition key and is in the ignition lock 2, there is a danger that the drier's knee will knock against the handle 3 of the ignition key during an accident. In order to reduce the danger and gravity of injuries, the stop connections 15 are constructed in such a way that the is second handle part 6 is released from the first handle part 5 without destruction if the f orce F, acting on the handle 3 exceeds the specified force F.. The second handle part 6 therefore gives way to the force F, and falls away so that the gravity of the injuries arising from the impact of a part of the driver's body and the handle 3 are reduced. If the force F, acting on the handle 3 is of a relatively low level, the impact on the handle 3 is absorbed by the material of the two handle parts 5, 6 without the key 1 being damaged.

If, as a result of an applied force F,, the second handle part 6 is released from the locked state, the shaft 4 remains inserted in the ignition lock 2. Only the first handle part 5 still projects out of the ignition lock 2. The first handle part 5 is constructed to be approximately U-shaped, approximately semi-circular or approximately half-drum-shaped, and so a user can grip the outer ends of the first handle part in order to provide the greatest leverage and can still turn the shaft 4 in the ignition lock 2. In this way the ignition can be switched off or the vehicle can be started again, even without the second handle part 6 being present.

The second handle part 6 is usually released from the first handle part 5 without destruction when subject to an impact, and so the second handle part 6 can be picked up again and inserted into the first handle part 5.

If the vehicle has an electronic immobilizer, the transponder 111 may be arranged in the first handle part 5 as shown in Figure 6. The motor vehicle can then be started, even without the second handle part 6 being in the vicinity.

In Figures 3 to 6, the elements of the same construction or function have the same reference symbols as in Figures 1 and 2. The two handle parts 5, 6 can each have two stop connections 15 on both sides, as is shown in Figure 1. However, one stop connection 15 alone is also sufficient, as is shown in Figure 3. This stop connection 15 can also be constructed to be somewhat stronger, for example wider or thicker, so that the second handle part 6 remains securely fastened to the first handle part 5, when the key 1 is turned in the ignition lock 2. When the key 1 is turned by hand the handle 3 or the second handle part 6 is loaded with a relatively small force F2. The force F2 'S in this respect a rotary force (torque) in contrast with the force F1 which represents a radial, axial or more or less lateral force with respect to the handle 3 or shaft 4.

Only when a specified force FN (for example of about 40N) is exceeded does the stop connection 15 become released and the second handle part 6 fall away f rom the rest of the key 1. The f orce F, usually exceeds the specified force F,, when the knee or another part of the body bumps or knocks against the handle 3. The specified force FN can be determined, for example, with accident tests, whereby the knee of a lifelike dummy knocks against the handle 3 of the ignition key. The level of the specified force PN depends, among other things, on the direction in which the knee knocks against the handle 3. This in turn depends on the position and arrangement of the ignition lock 2 with respect to the user. When the key 1 is turned, the force F2 (or the corresponding torque) on the handle 3 is substantially less than when the knee bumps against the handle 3. The locked states 15 must be capable of being maintained such that the second handle part 6 does not become released from the first handle part 5 when the key 1 is turned.

Figures 4 and 5 show another exemplary embodiment of the invention. In this exemplary embodiment the is upper part 9 and the lower part 10 of the second handle part 6 extend along the entire length of the handle 3. The first handle part 5 is locked into place from the front, i.e from the direction of the shaft 4, into the front side of the second handle part 6. The first handle part 5 has two side wings 18 on which the stop connections 15 can be arranged. Likewise, a single stop connection 15 may be arranged in the region of the shaft 4 in the middle of the handle parts 5, 6, as shown in Figure 4.

In this exemplary embodiment it is particularly important that the electronic unit 8, 11 in the handle 3 is sealed to the outside. For this purpose, a sealing material 19 is arranged between the upper part 9 and the lower part 10 of the second handle part 6, which sealing material is compressed when the upper part 9 and the lower part 10 are joined together and in the process seals the joint between the upper part 9 and the lower part 10. This is achieved by means of conical housing parts between which the sealing material 19 is arranged and which are pushed one on top of the other. In this way the interior of the key handle is protected from the outside against soiling and environmental influences.

In Figure 6 the two handle parts 5, 6 are shown separated from each other. The transponder 111 is arranged in the first handle part 5, which transponder transmits and/or receives data or power by way of the coil 12. The first handle part 5 is constructed here to be approximately U-shaped. The first handle part 5 is injection-moulded from plastics, for example polyamide, whereby injection-moulding around the shaft 4 also takes place during the injection-moulding procedure, so that the shaft is connected to the first handle part 5 in such a way that it cannot be released. The coil 12 is arranged as far forward as possible in the vicinity of the shaft 4, so that when the key 1 is inserted into a lock the coil is arranged as close to the coil 13 of the ignition lock 2 as possible.

When the user grips the side wings 18 of the first handle part 5 the key 1 can be turned in the ignition lock 2. In addition, the first handle part 5 in this embodiment has a predetermined breaking point 20 which breaks when a very great force F, acts on the f irst handle part 5. The magnitude of the f orce F, at which the predetermined breaking point 20 breaks depends on the material thickness of the predetermined breaking point 20. The predetermined breaking point 20 is formed as a taper (circumferential groove) in the material of the first handle part 5. When a certain force F1 is applied, the f irst handle part 5 breaks along the predetermined breaking point 20. In this way injuries may be further reduced in a situation in which only the first handle part 5 together with the shaft 4 is still in the ignition lock 2.

The transmitting unit 8 with its buttons 7 is arranged in the second handle part 6. Parts of stop connections 15, i.e. locking hooks 16 or latches 17, are arranged on those side walls of the second handle part 6 which are directed towards the first handle part 5. These parts lock into place in corresponding latches 17 and locking hooks 16 of the first handle part 5 when the two parts are joined together. In this exemplary embodiment three stop connections 15 are arranged in the handle 3, namely two on the outer sides (on the side wings 18) and one in the middle of the handle parts 5, 6.

When the two handle parts 5, 6 are joined together the connection point or impact point 21 (joint) can be sealed in a surface-locking manner so that no groove/impact point/joint 21 is visible to the outside. However, an impact point 21 can also be produced where a small groove remains visible and can be felt.

The key 1 can be used for the mechanical operation or also for the electrical operation of the ignition lock 2 or of door locks. For the electrical operation of the ignition lock 2 the key 1 has the transponder ill and for the electrical operation of door locks the transmitting unit 8 is provided. For the mechanical operation of the ignition lock 2 (turning the key 1 in the ignition lock 2) the shaft 4 has a mechanical coding or a key bit.

The invention has the advantage that an impact, for example an impact of a part of the driver's body with the handle 3, does not result in the destruction of the first and the second handle part 5 and 6. Only when a very great impact occurs is destruction, for example of the stop connections 15, brought about. In most cases the second handle part 6 can be picked up again and inserted into the first handle part 5 so that there is again a complete key 1 with unrestricted function.

The handle parts 5, 6 are preferably manufactured from an elastic material, such as a plastic (for example polyamide) which is partially reinforced with fibre glass. Moreover, a flexible cover, not shown, can be arranged over the second handle part 6, by means of which an impact against the handle 3 is additionally cushioned.

The key 1 with the separable handle parts 5, 6 has the advantage that the first handle part 5 together with the shaft 4 can be universally used for many locks. The second handle part 6 with the transmitting unit 8 only needs to be joined together with the first handle part 5 to form a unit at the end of the manufacture of a motor vehicle or when it is with the customer. Beforehand, it is possible, to a limited extent, to start the motor vehicle with the first is handle part 5 because with this part alone a turning of the key 1, can occur. This is because the first handle part 5, owing to its geometric shape (for example U shaped, semi-circular or half-drum-shaped) presents a sufficiently large lever, with the help of which the key 1 can be turned.

The key 1 in the form shown is preferably suitable as a key 1 for a steering wheel lock or ignition lock 2. The ignition lock 2 is arranged next to the steering column, and as a result of an impact in the event of a rear end collision, the knees can knock against the handle 3 of the key 1 with more or less force. The danger of injury to the knee and the gravity of the injuries are reduced with the key 1 in accordance with the invention.

However, the key 1 can also be a key 1 for office furniture, for example a desk, by means of which the danger of injury in the event of knocking a part of the body against the handle 3 is reduced because the second handle part 6 mostly falls away from the first handle part 5 undestroyed if someone knocks against the key 1.

The invention is also suitable for other applications where there is danger that a person can knock against the handle 3 of a key 1 unintentionally.

It is not essential that the key 1 in accordance with the invention includes an electronic unit, like the transmitting unit 8 or the transponder 111 in its handle 3. The releasing of the two handle parts 5, 6 in the event of force action on the handle 3 is, in the case of the invention, not influenced by an electronic unit which is possibly present. in this way the handle parts 5, 6 can each be manufactured in one piece and solidly from plastics or another equivalent material.

A transponder 111 is a transmitting and receiving unit which is advantageously constructed on a semiconductor chip. The coil 12 which is electrically connected to the chip is used as the transmitting and receiving aerial. After a signal is received the transponder 111 automatically transmits a response signal. The response signal contains an identifier of the transponder 111.

Claims

1. A key, comprising a key handle having two handle parts which are releasably locked with each other, whereby the first handle part is fastened to a key shaft and the second handle part is releasable from the first handle part when a force which is greater than a specified force acts on the key handle.

2. The key according to claim 1, wherein the second handle part has a transmitting unit, by means of which, upon the operation of a button, a coded signal to lock or unlock a door lock is wirelessly transmitted.

3. The key according to claim 1 or 2, wherein the first handle part has a transmitting and receiving unit which, as a result of the reception of a coded signal wirelessly transmits another coded signal, by means of which an immobilizer of a motor vehicle is activated or deactivated.

4. The key according to one of the preceding claims, wherein latches are arranged in the first and/or in the second handle part, in which locking hooks of the second or first handle part, respectively, are locked into place.

5. The key according to one of the preceding claims, wherein the second handle part has a predetermined breaking point which breaks when the specified force acting on the first handle part is exceeded.

6. The key according to one of the preceding claims, wherein the first and the second handle part are manufactured from plastics in one piece together with the latches and locking hooks.

1

7. The key according to one of the preceding claims, wherein the first handle part is constructed to be wider than the key shaft, whereby a lever is produced, with the help of which a turning of the key in a corresponding lock is made possible when the first handle part is gripped.

8. A key substantially as herein described, with reference to the accompanying drawings.