JPH04108969A - Lock system - Google Patents

Abstract

PURPOSE:To make forgery of a lock system extremely difficult by using a metal that generates magnetic modification from non-magnetic to ferromagnetic through mechanical deformation, as a key of the lock system. CONSTITUTION:A condition where a key 10 is not inserted into a key hole 21, is the same as where a non-magnetic key 10A is inserted into the key hole 21, and a magnet 24 of an inner cylinder 20 is pushed out through the elastic force of a bias spring 23, and the end part of the magnet 24 is engaged with a through hole 32 of an outer cylinder 30. The inner cylinder 20 is not rotated to the outer cylinder 30, and a locked condition is obtained thereby. When a normal key 10 is inserted into the key hole 21, the magnet is attracted by the ferromagnetic part of the key 10 through magnetic function, and the magnet 24 surpasses the elastic force of the bias spring 23, and is thus attracted inside. The magnet 24 escapes from the through hole 23 of the outer cylinder 30, and is further buried in the surface of the inner cylinder 20, which is in a rotatable condition, and a lock is released thereby.

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a lock device in which a key is made of a special metal having a ferromagnetic part and a non-magnetic part.

(Prior Art) In conventional lock devices, a groove is formed in the key, or a magnet is embedded in the key with different S and H magnetic poles. Then, by inserting the key into the inner cylinder of the lock device, if the key is a regular key, the groove or magnetic pole will move the blocking member between the outer cylinder and the inner cylinder to either side, causing the inner cylinder to rotate. movement is allowed.

(Problem to be Solved by the Invention) However, with a key having a groove, it is extremely easy to counterfeit the same key by machining. Furthermore, even keys with embedded magnets can be easily counterfeited by detecting the magnetic poles of the magnets and changing the embedding.

This invention was made in view of the above-mentioned circumstances, and an object of the invention is to use a metal that undergoes an IiB transformation from non-magnetic to ferromagnetic through mechanical deformation, so that counterfeiting is extremely difficult. An object of the present invention is to provide a locking device having a key.

Structure of the Invention (Means for Solving the Problem) This invention relates to a locking device, and the above-mentioned object of the invention is to provide a fixed outer cylinder having a first magnetic tumbler which is biased outwardly. and a second magnetic tumbler mounted inside the fixed outer cylinder and urged outward; an inner cylinder whose rotation is prevented by the second magnetic tumbler; and a key that partially undergoes a magnetic transformation from magnetic to ferromagnetic using a metal that undergoes a magnetic transformation from magnetic to ferromagnetic, and when the key is inserted into the inner cylinder, the second magnetic tumbler is inserted into the inner cylinder. This is achieved by making the inner cylinder rotatable by pulling it towards the inner cylinder.

(Function) When steel is quenched from the austenite region at a critical cooling rate or higher, martensite is obtained. The temperature at which martensite occurs is called the Ms point, and it depends on the chemical composition of the steel.

However, martensite may be induced even when unstable austenite is processed, and the temperature at which it occurs will shift to a higher temperature than the M8 point depending on the degree of processing, but if it becomes too high above the Ms point, martensite formation may occur due to processing. It disappears. This point is called the Md point, and the martensite formation caused by processing is called processing-induced transformation. In this case, stress is applied to process austenite, and this process strain induces and progresses martensitic transformation.

Large plasticity occurs as martensitic transformation progresses, but this is called transformation-induced plasticity (transformation-induced plasticity).
n-induced plasticity, abbreviated as TR
This transformation-induced plasticity is a type of superplasticity. That is, the austenite-martensitic transformation occurs during processing, and the stress concentration that caused the processing-induced transformation is alleviated by the occurrence of the transformation, resulting in considerably high ductility.

This invention uses a metal that undergoes the process-induced transformation as described above and undergoes magnetic transformation from non-magnetic to ferromagnetic due to mechanical deformation as a key for a lock device.

However, stainless steel is classified as shown in Table 1 below.

Also, austenitic stainless steel is 301,304.3
The stainless steel used in this invention is a stainless steel that has a metastable austenite phase at room temperature, that is, the M1 point is above room temperature.
The point is an austenitic stainless steel below room temperature. Then, by subjecting the austenitic stainless steel to mechanical deformation such as rolling, enforcing, bunching, etc. at room temperature, nonmagnetic austenite transforms into ferromagnetic martensite. This is irreversible unless heated above several hundred degrees Celsius.

FIG. 12 shows, by way of example, how a recess 2 of an austenitic stainless steel 1 has been made ferromagnetic by pressing or embossing. By forming a ferromagnetic part in any part of the key in this way, if the magnetic tumbler is placed in the corresponding position of the ferromagnetic part when the key is inserted, the magnetic tumbler and the inserted key can be The lock can be unlocked or locked by magnetic action with the ferromagnetic part.

(Example) FIG. 1 shows the external appearance of a key 1O used in the present invention, in which a striped diagonal line portion 11 in the insertion portion is a ferromagnetic portion. By inserting the key 10 into the inner cylinder of the lock device, the ferromagnetic part 11 generates a magnetic action with the magnetic tumbler provided inside to unlock the lock, and by removing the key 10, the entire interior becomes non-magnetic. It is locked by being

Next, the manufacturing process of the key 10 will be explained with reference to FIG. 2. The austenitic stainless steel described above is machined to obtain the key member 12 as shown in FIG. 2 (8).

In this case, the final position of ferromagnetism is determined by the position of the convex portion 12A, and the final magnetic (magnetic strength) There will be some difference. The higher the convex portion 12Δ, the higher the rolling ratio and the stronger the magnetic property. When the machining shown in Fig. 2 (8) is completed, the key part 12 for m machining is completed.
Since the entire surface of is made into a strong core R, it is made non-magnetic by heat treatment, that is, made into a single austenite phase (the state shown in FIG. 2 (8)). By rolling only the convex portions of the key member 13 that has been made non-magnetic by heat treatment,
A key lO as shown in FIG. 2(C) is obtained in which only that portion is made ferromagnetic. The shaded area in the figure shows the ferromagnetic part. Then, the surface of the key lO shown in FIG. 2 (C) is polished to remove dirt (uras, oxide films, etc.), irregularities, etc., and finally no residual distortion remains due to electric field polishing, chemical polishing, etc. It is preferable to finish by polishing.

Here, in surface polishing, the surface to be polished is rubbed with a grindstone, abrasive paper, etc. and mechanically scraped, resulting in a deformed damaged layer (altered layer) of several micrometers. Further, in electric field polishing, the material to be polished is used as a positive electrode, and both positive and negative electrodes are simultaneously immersed in an electrolytic solution and a voltage is applied. In this case, electrons are taken away from the positive electrode, so atoms on the surface of the material are ionized and released into the electrolyte. Since there is no mechanical damage, no altered layer is formed, and this electric field polishing is performed to remove the altered layer produced by mechanical polishing.

Furthermore, chemical polishing uses certain corrosive liquids (hydrochloric acid, sulfuric acid, aqua regia, etc.)
The purpose is the same as electric field polishing. Therefore, it is better to perform either electric field polishing or chemical polishing.

The lock device of the present invention includes a rotatable inner cylinder having a keyhole for inserting the key 10 as described above, and an outer cylinder which is fixed by fitting the inner cylinder. That is, FIG. 3 shows a cross-sectional view of the front structure of the inner cylinder 20, in which a key hole 21 for inserting the key 10 is provided, and FIG. - As shown in FIG. 7, a plurality of cut holes 22 are made, and some of the cut holes 22 (two in this example) are provided with bias springs 23 having an outward elastic action. Through the cylindrical magnet 24
is attached to form a second magnetic tumbler. If there is no ferromagnetic material in the key hole 21, the magnet 24
Due to the elastic force of the bias spring 23, the distal end thereof protrudes from the surface of the inner cylinder 20 as shown in FIG. On the other hand, FIG. 4 shows a cross-sectional view of the front structure of the outer cylinder 30 into which the inner cylinder 20 is fitted.
It has a mounting hole 31 as shown in FIGS. 5 to 7.
A plurality of through holes 32 are opened along the cutting direction. A magnet 34 with a stopper is attached to some (two in this example) of the through holes 32 via bias springs 33 having an outward elastic action, forming a first magnetic tumbler. ing. When the keyhole 21 is not ferromagnetic, the tip of the magnet 34 is recessed below the surface of the mounting hole 31 by the elastic force of the bias spring 33. A second magnetic tumbler attached to the inner cylinder 20 and the outer cylinder 3
In this example, the first magnetic tumblers attached to the first magnetic tumblers 0 and 0 are arranged alternately. Also, for convenience of drawing, the keyhole 21 is shown between the inner cylinder 20 and the mounting hole 31 of the outer cylinder 30.
Although gaps are provided between the magnet 24 and the key 10, between the magnet 24 and the cut hole 22, and between the magnet 34 and the through hole 32, they are actually fitted and can rotate or slide. There is a slight difference in size.

In such a structure, if the key 10 is not inserted into the key hole 21, a non-magnetic key 10A shown in FIG.
is in the same state as when inserted into the key hole 21, and the inner cylinder 20
The magnet 24 is pushed outward by the elastic force of the bias spring 23, and the tip of the magnet 24 is engaged with the through hole 32 of the outer cylinder 30. Therefore, the inner cylinder 20 does not rotate relative to the outer cylinder 30 and is in a locked state. When a normal key 10 as shown in FIG. 1 is inserted into the key hole 21, the key 10 as shown in FIG.
A magnet 24 attached to the ferromagnetic part of the inner cylinder 20
The magnet 24 overcomes the elastic force of the bias spring 23 and is pulled inward. Therefore, the magnet 24 comes out of the through hole 32 of the outer cylinder 30 and is further retracted below the surface of the inner cylinder 20, so that the inner cylinder 20 becomes rotatable and unlocked. In this case, since the opposing position of the magnet 34 of the outer cylinder 30 is the non-magnetic part of the key 10, no change occurs. On the other hand, when the key 10B, whose entire key is made of ferromagnetic material, is inserted into the keyhole 21, the inner cylinder magnet 24 acts with the ferromagnetism of the key 10B and retracts from the surface of the inner cylinder 20, as shown in FIG. However, since the magnet 34 of the outer cylinder 30 also interacts with the ferromagnetism of the key 10B,
The magnet 34 overcomes the elasticity of the bias spring 33 and is pulled inward and advances into the cut hole 22 of the inner cylinder 20.

Therefore, the inner tube 20 and the outer tube 30 remain locked.

From the above, in this embodiment, the lock is unlocked only when the key 10 as shown in FIG. 5 is inserted into the key hole 21, and when the ferromagnetic and non-magnetic 1
Or it is locked by the second magnetic tumbler and cannot be unlocked.

In the above-described embodiment, the magnetic tumblers of the inner tube 20 and the outer tube 30 are provided horizontally, but they may also be provided vertically as shown in FIGS. 8(A) and 8(B).

Further, if the cylindrical magnetic tumbler is installed horizontally and the outer cylinder magnetic tumbler is installed vertically, the distance to the inserted key will be closer, and locking and unlocking operations can be performed even with a weak magnet.

Furthermore, the magnet may be provided at any position on the left, right, top, or bottom of the keyhole 21, or even at all positions.

As shown in FIG. 9(A), the key 10 is manufactured by first cutting out a flat plate 40 made of austenitic stainless steel, heat-treating it to make it non-magnetic, and then processing it with a press, as shown in FIG. 9(B). Alternatively, only the processed portion may be made ferromagnetic. In this case as well, the surface is then flattened by polishing. Furthermore, a key may be created using a metal that undergoes magnetic transformation from ferromagnetic to non-magnetic due to heat, with a non-magnetic portion formed using a laser or the like. Further, the key does not have to have a general shape as shown in FIG. 1, but may be a cart key 15 as shown in FIG. 10. In FIG. 10, the mark 158 indicates the ferromagnetic portion.

On the other hand, in the above methods, the ferromagnetic and non-magnetic properties of the key are detected by a magnet to lock and unlock the key, or the ferromagnetic and non-magnetic properties are read by a magnetic sensor using a magnetoresistive element, a Hall element, etc., and the key is locked and unlocked. locked.

It is also possible to unlock the door. In other words, Fig. 11 (
As shown in (8), a magnetoresistive (MR) sensor 50 is installed above (or on the side) of the key lO, and by moving either of them relatively, a magnetic resistance signal as shown in (b) of the same figure is generated. M
Since S is output, information on the key 10 can be read by binarizing this magnetoresistive signal MS at a predetermined threshold Tflo and performing counting or the like. Further, a groove similar to the conventional one may be added to the key lO.

On the other hand, in the embodiments shown in FIGS. 3 and 4, a magnetic tumbler is provided on one side of the outer cylinder 30.
A pair of magnetic tumblers may be provided on each side. In this case, even if the key is embedded with a magnet and inserted, the magnetic tumbler on one side will protrude outward, so the lock will not come off, increasing security. In addition, since the magnetic permeability changes greatly depending on the amount of rolling when making the key,
It is possible to convert information into multiple values. Therefore, when reading with a magnetic sensor, multivalued information is read, and when reading with a magnet, the information becomes complicated if it is set to respond only to ferromagnetism of a certain strength or higher by manipulating the bias spring strength, etc. Counterfeiting becomes more difficult.

Effects of the Invention As described above, according to the lock device of the present invention, it is impossible to visually distinguish between ferromagnetism and non-ferromagnetism of the key itself, and even if ferromagnetism and non-magnetism could be distinguished by a magnet. By embedding a magnet, rotation of the key can be completely prevented, making counterfeiting of the key extremely difficult, and a lock device with extremely high safety can be provided.

[Brief explanation of the drawing]

Fig. 1 is an external view showing an example of the key used in this invention, Fig. 2 is a drawing showing its manufacturing process, Fig. 3 is a front view of the inner cylinder used in this invention, and Fig. 4 is an illustration of the inner cylinder. A cross-sectional front view of the lock device fitted into the outer cylinder, Fig. 5 is a cross-sectional plan view showing the situation when a normal key is inserted, and Fig. 6 is a cross-section showing the situation when a non-magnetic key is inserted. A plan view, Fig. 7 is a cross-sectional plan view showing the situation when a ferromagnetic key is inserted, and Fig. 8 (
8) and (B) are a front view of an inner cylinder and a front view of a lock device in which the inner cylinder is fitted into the outer cylinder, showing another embodiment of the present invention, and Fig. 9 is a diagram showing another manufacturing process of the key. , FIG. 1θ is a diagram showing other keys that can be used with this invention, and FIGS. 11(A) and (B
) is a diagram for explaining the key information reading, and FIG. 12 is a diagram showing a state in which magnetic transformation occurs locally due to mechanical deformation. 1...Austenitic stainless steel, 10. IOA
IOB...Key, 15...Cart key, 20...
- Inner cylinder, 24.34... Magnet, 21... Keyhole, 30... Outer cylinder, 50... Magnetoresistive sensor. Shibasuzu $6 Zubanzu

Claims (1)

[Claims] 1. A fixed outer cylinder having a first magnetic tumbler biased outward, and a second magnetic tumbler mounted inside the fixed outer cylinder and biased outward;
an inner cylinder whose rotation is prevented by a magnetic tumbler;
a key that partially undergoes a magnetic transformation from non-magnetic to ferromagnetic through mechanical deformation, and when the key is inserted into the inner cylinder, the second A locking device characterized in that the inner cylinder can be made freely rotatable by drawing the magnetic tumbler inward.