GB2214555A - Square threaded lock - Google Patents

Abstract

A square threaded lock consisting of a threaded key 1, a threaded member 2, a core and a lock body 4. The core and lock body have several semispherical recesses 33 and holes 43 respectively in alignment with each other to receive tumbler pins. <IMAGE>

Description

TITLE: SQUARE-THREADED LOCK The present invention relates to a lock, and more particularly to a square-threaded lock which uses a threaded key to match with a square threaded member inside a bore of the square-threaded lock.

Nowadays the role that lock plays is very important to daily life. There are many kinds of locks; the most popular lock is hanging lock, the use of which is very extensive; generally, it can be used for locking cabinets, tool boxes, door latches, etc.

Since the use and importance of locks are known, it is necessary to improve the structure of the locks. The present invention relates to an improved lock structure which aims at eliminating the drawbacks of conventional locks.

In the past, we often found that many shop counters were opened by theives though the shop counters had been locked; or, a bicycle would be stolen in less than three minutes. Obviously, the protective value of conventional locks is, to say the least, questionable. Even a wire can open the lock. The main reason is that the structure of the locks are familiar to ordinary people; therefore, it is easy for thieves to take advantage of the situation. For the reasons stated above, the inventor of the present invention has designed an improved lock structure as presented hereinbelow.

It is therefore a primary object of the present invention to provide a square-threaded lock having an anti-pick mechanism therein.

Another object of the present invention is to provide a square-threaded lock which assures a higher level of protection on doors than was previously available.

These and other objects would become apparent after a careful reading of the detailed description provided hereinafter, with appropriate reference to the attached drawings.

Fig. 1 is an exploded view of a square threaded lock according to the invention; Fig. 2 is a cross-sectional view of a lock body according to this invention; Fig. 3 is a cross-sectional view of a square threaded lock with a key screwed therein according to this invention.

Referring to Fig. 1, it can be seen that this invention comprises a key 1, a threaded member 2, a core 3, a lock body 4 and a C-shaped ring 5. The attaching mechanism between the lock body 4 and the core 3 is the same as that of the prior art, i.e., driving pin-tumblers 45 and reciprocating pin-tumblers 44 are slidably received by semispherical recesses 33 and holes 43. A threaded member 2 is mounted within a core 3 to match with a thread-shaped of key 1, thereby achieving the object of locking and unlocking.

Reference numeral 4 designates a lock body 4 provided with a cylindrical bore 41 extending lengthwise therethrough below its center axis, for the reception of a core 3. In other words, the core 3 is mounted in the lock body 4. The outer end of the bore 41 is provided with a circumferential lip 48 extending radially from the bore 41 to the surface of the lock body 4. Besides holes, there is a fixing hole 49. A plurality of driving pin-tumblers 45 and reciprocating pin-tumblers 44 of different lengthsare respectably slidably received in said holes 43. Attached to each set of driving and reciprocating pin-tumblers is a spring 46 with a disk 47 set thereto.

The core 3 is a cylinder with a bore 31 at the center thereof. At the upper side of the front face of the core 3, a small bore 32 is provided. At the other end of the core 3 is a little projection as indicated by reference numeral 37. A plurality of semispherical recesses 33 are arranged at the periphery of the core 3, in addition to a ball retainer 34 for fitting a ball 33. An annular groove 35 is disposed the periphery of the core 3, which is used to be mounted with a C-shaped ring after inserting the core 3 into the lock body 4, whereby the core 3 can be mounted and rotated within the lock body 4.

The threaded member 2 has square threads thereon and is mounted within the bore 31 of the core 3.

The key 1 has a threaded end 11. There is an oblique tip 13 at the threaded end 11 . In addition, there are a plurality of indentations 12 with different depths to cooperate with the reciprocating pin-tumbler 44. A tip 14 is disposed at the threaded portion 11 of the key 1 to be matched with the hole 32 at the front end of the core 3, thereby enabling the core key 1 to rotate the core 3.

To assemble this invention, the threaded member 2 is first mounted within the bore 31 of the core 3.

Then the core 3 is inserted into the cylindrical bore 41 of the lock body 4. The holes 43 are in alignment with the semispherical recesses 33, and the fixing hole 49 are in alignment with the ball retainer 34.

Referring to Fig. 2, after assembly, the reciprocating pin-tumblers 44 reach the gap between the threads 21 of the threaded member 2. In fact, the holes and semipherical recesses can be in any direction so far as they can be matched with the threaded member 2.

Referring now to Fig. 3, it can be seen that to use this invention the key 1 is screwed into the bore 31. The reciprocating pin-tumblers 44 are lifted by an oblique tip 13 at the end of the threaded portion 11.

When the key 1 is fully inserted into the core 3, due to the fact that the width of the threaded portion 11 is narrower than that of the space between the square threads 21 of the threaded member 2 and the effect of the combination of the pushing force of springs 46 and slot 12 of the key 1, the key 1 is pulled inwards thereby making the tip 14 to be engaged with the hole 32 and at the same time pushing the driving pintumblers 44 respectively, whereby the key 1 urges the core 3 to rotate and opens the lock. However, after the core 3 is rotated, the reciprocating pin-tumbler 44 is biased off the hole 43 of the lock body 4 thereby engaging with the slot 12 and securing the key 1. The holes 43 be in alignment with reciprocating pintumbler, then the key 1 can be drawn out. In order to facilitate the user to do this relocation, a ball 36 and a spring 46 are disposed in the fixing hole 49, thereby making the ball 36 fall into the ball retainer 34 when the core 3 is rotated to the proper position.

Furthermore, when the user turns the core 3 to the proper position and intend to draw out the key, the key must be pulled out a little, thereby disengaging the tip 14 from the hole 32, then the key is screwed out.

The present invention uses a thread-shaped key instead of an ordinary piece-like key, which provides much better protection.

Claims (3)

CLAIMS:

1. A square-threaded lock comprising a key (1), a threaded member (2), a core (3) and a lock body (4), and a C-shaped ring (5) wherein said core (3) is mounted in said lock body (4), said core (3) and said lock body (4) respectively having a plurality of semispherical recesses (33) and holes (43) respectively in lengthwise alignment therealong; a plurality of reciprocating pin-tumblers (44), driving pin-tumblers (45) and springs (46) being disposed in said semispherical recesses (33) and holes (43), a fixing hole (49) being arranged at said lock body (4) and a ball retainer (34) being arranged at said core (3) so that a ball (36) can be put therein; ; said key (1) having threaded portion (11) at one end thereof, a front tip (13) of said threaded portion (11) of said key (1) having an oblique face thereby pulling reciprocating pin-tumblers (44), at an external side of said threaded portion (11) of said key (1) having slots (12) of different depths to cooperate with said reciprocating pin-tumblers (44), gap between of threads of said threaded portion (11) of said key is small than that of square threads (21) of said threaded member (2).

2. The square-threaded lock substantially as hereinbefore described with reference to the accompanying drawings.

3. Any novel feature or combination of features disclosed herein.