GB2134970A

GB2134970A - Knob for a vehicle door lock

Info

Publication number: GB2134970A
Application number: GB08403401A
Authority: GB
Inventors: Stephen Frank Golder
Original assignee: Individual
Current assignee: Individual
Priority date: 1983-02-09
Filing date: 1984-02-09
Publication date: 1984-08-22
Also published as: GB8403401D0

Abstract

A thief resistant vehicle door lock has a knob, comprising a cylindrical body 13 and a head 14, attached by an internal screw thread to a mating thread on an arm 12. The knob is made from a flexible material such as a rubber having a shore hardness in the range 40-90 and preferably 70-80 such that the knob bends when attempt is made to illegally enter the vehicle by using the knob. <IMAGE>

Description

SPECIFICATION Knob for a vehicle door lock This invention relates to a knob for a vehicle door lock of the kind having an internally disposed arm which is usually positioned adjacent a pillar of the door, and to a vehicle door lock utilising such a knob.

Figure 1 shows, in schematic form, a vehicle door lock of the aforementioned kind. The door lock 1 has a latch 2 for securing the door to a frame and the latch is released by an external, pivoting door handle 3 connected to the internal mechanism of the lock by a rod 4 and by an internal pivoting door release handle 5 connected to the latch releasing mechanism by a rod 6. Also connected to the lock 1 is a mechanism 7 for locking the latch, the mechanism being provided internally of the door. The mechanism 7 has a pivoting member 8 connected to the internal lock mechanism, a link 9 connected between the member 8 and one arm of a bell crank 10 which is pivotal about a pin 11 with the other arm of the bell crank remote from the link 9 connected to a vertical arm 12 having a cylindrical cross-section and which passes through the internal door capping (not shown).The arm 12 is provided with an external screw thread for mating with an internally supplied screw thread on a cylindrical, rigid, plastics knob 13 having an enlarged head 1 4. The door lock mechanism is well known per se and the latch 2 is normally set into a locked position either by a key inserted into a keyhole in the external face of the car door (or handle 3) or by depression of knob 13 which thereby causes the bell crank 10 to rotate about pivot 11 and pull link 9 to rotate member 8 and thereby secure the latch 2. To unlock the latch 2, the key is rotated in the opposite direction in the outer keyhole or the knob 13 is pulled vertically upwards.

Referring now to Figure 2, there is shown a part view of the side of a four door vehicle. In Figure 2, there is shown a front door 20 and a rear door 21 both of which are closed against a door pillar 22. Each door has a respective frame 23, 24 abutting a seal provided along the pillar 22 and around the top portion 25, 26 of the door frame, the vehicle roof being reference 27.

From statistics seen by the applicant, it is understood that a motor vehicle is stolen in the U.K. at a rate of approximately one every two minutes and it is known that a substantial proportion of the vehicles stolen are due to the thief unlocking the vehicle door by illicitly lifting knob 13. In Figure 2, knob 13 is shown in a raised position and knob 13' on the rear door 21 is shown in a depressed position.

A known method of raising knob 13 is to utilise a stiff plastics strip 30 such as that strip used for binding packing cases. The method normally employed is to bend the strip approximately in half and to feed the bent portion of the strip between the door frame 23 and the pillar 22 and due to the stiffness of the strip it may readily be pushed past the door seal. By pushing and pulling on the free ends of the strip 30, so it may readily be positioned over the head 14 and around the body of the knob 13.In positioning the strip 30 around the knob 13, it is required that it be inserted through the door and around the knob approximately perpendicularly to the axis of the knob 1 3. Once the strip 30 is positioned around the knob, then it is pulled laterally to provide good grip around the body of the knob and then the ends of the strip are moved upwardly as shown by the position of the strip in broken lines. In moving the strip 30 upwardly and by continually exerting lateral force upon the knob 33, so the knob may be raised to unlock the latch 2.

It is an object of the present invention to provide a knob for a vehicle door lock and a vehicle door lock embodying such a knob in which the foregoing means of illegal entry to a vehicle may be thwarted.

According to one aspect of this invention there is provided a knob for a car door lock of the kind having an internally disposed arm which is usually positioned adjacent the door pillar, said knob being adapted to be secured to said arm and being made from a resilient material having sufficient strength for actuation of said arm in a normal, desired, direction of actuation of said arm, but which is flexible so that the knob bends when subjected to force in an abnormal, undesirable direction of actuation, whereby an entry to the vehicle utilising said knob may not be made through the junction between the door and door frame.

According to a further aspect of this invention there is provided a vehicle door lock of the kind having an internally disposed arm which is usually positioned adjacent the door pillar, and to which is secured a push/pull knob, said knob being made from a resilient material having sufficient strength for actuation of said arm in a normal, desired direction of actuation of said arm but which is flexible so that the knob bends when subjected to force in an abnormal, undesired direction of actuation, whereby an entry to the vehicle utilising said knob may not be made through the junction between the door and door frame.

Normally, the direction of actuation of said arm and knob is in a substantially vertical direction.

Preferably the knob is made from a flexible polymeric material which may be weatherproof rubber having a shore hardness in the range 4090 and preferably in the range 70-80.

Advantageously, for attachment to the arm, said arm is provided with an external screw thread and said knob is correspondingly provided with an internal screw thread.

Conveniently the knob is cylindrically shaped with an enlarged head section, and said screw thread is provided in the direction of the longitudinal axis thereof.

The invention will now be described with reference to Figure 3 of the accompanying drawings which is a side view of a four door vehicle similar to that shown in Figure 2, but in which the knob according to the present invention is utilised.

The knob 33 for the car door lock shown in Figure 3 is made from a flexible polymeric material like rubber, the characteristics of which are defined in the function the knob is to perform.

Such a material may be a mixture of ethylinepropylene (EPDM) and styrobutidene or that known under the trade name of neoprene. The material used should have a shore hardness in the range 40-90 and preferably in the range 7080. The knob 33 has a cylindrical body with an enlarged head section 14 and is internally screw threaded from the end opposite the head along the axis thereof to mate with a corresponding screw thread on the end of arm 12, but it is ensured that the arm 12 does not extend into the body of knob 33 above the door capping 34 to any significant extent for reasons which will become apparent hereinafter.

When now a plastic strip 30 is inserted between the door frame 23 and door pillar 22 and positioned around the body of knob 33, it is required that a lateral force be exerted upon the knob 33 so that it may be lifted from the angle of entry.

Because the knob of the present invention is made from a resilient material so the knob bends under such lateral force and the strip 30 slides off from around the body of the knob. For this reason, it is desirable that the head 14 is not made of too large a diameter to prevent such sliding off of the strip 30 and it is, in fact, preferred that the head 14 is omitted.

Thus by replacing the normally supplied hard plastics knob 33 by a resilient rubber knob 33, so the forementioned means of entry to a vehicle by utilising a plastics strip or similar strip through-a door seal, may be thwarted.

Claims

1. A knob for a car door lock of the kind having an internally disposed arm which is usually positioned adjacent the door pillar, said knob being adapted to be secured to said arm and being made from a resilient material having sufficient strength for actuation of said arm in a normal, desired, direction of actuation of said arm, but which is flexible so that the knob bends when subjected to force in an abnormal, undesirable direction of actuation, whereby an entry to the vehicle utilising said knob may not be made through the junction between the door and door frame.

2. A knob as claimed in claim 1 wherein it is made from a flexible polymeric material.

3. A knob as claimed in claim 1 or 2 wherein said material is a weatherproof rubber having a shore hardness in the range 40-90.

4. A knob as claimed in any preceding claim wherein said material is a weatherproof rubber having a shore hardness in the range 70-80.

5. A knob as claimed in any preceding claim wherein an internal screw thread is provided for mating with a thread on said arm.

6. A knob as claimed in claim 5 wherein the knob is cylindrically shaped with an enlarged head section, and said screw thread is provided in the direction of the longitudinal axis thereof.

7. A vehicle door lock of the kind having an internally disposed arm which is usually positioned adjacent the door pillar, and to which is secured a push/pull knob, said knob being made from a resilient material having sufficient strength for actuation of said arm in a normal, desired direction of actuation of said arm but which is flexible so that the knob bends when subjected to force in an abnormal, undesired direction of actuation, whereby an entry to the vehicle utilising said knob may not be made through the junction between the door and door frame.

8. A vehicle door lock as claimed in claim 7 wherein the knob is made from a flexible polymeric material.

9. A vehicle door lock as claimed in claim 7 or 8 wherein said material is a weatherproof rubber having a shore hardness in the range 40-90.

10. A vehicle door lock as claimed in claim 7, 8 or 9 wherein said material is a weatherproof rubber having a shore hardness in the range 70-80.

11. A vehicle door lock as claimed in any of claims 8 to 10 inclusive wherein for attachment to the arm, said arm is provided with an external screw thread and said knob is correspondingly provided with an internal screw thread.

12. A vehicle door lock as claimed in claim 11 wherein the knob is cylindrically shaped with an enlarged head section, and said screw thread is provided in the direction of the longitudinal axis thereof.

13. A knob for a car door substantially as herein described with reference to Figures 1 and 3 of the accompanying drawings.

14. A vehicle door lock substantially as herein described with reference to Figures 1 and 3 of the accompanying drawings.