JPH10131559A - Breaking prevention cylinder lock - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a cylinder lock incapable of making wicked and unjust unlocking by covering a key-hole of the cylinder lock with a cover having a key insertion-hole and consisting of a material with high hardness and toughness in turnable manner, and protecting the cylinder lock from cutting by a drill or impulsive breaking by a hammer. SOLUTION: A hard cover 35 quenching special steel such as nickel chrome molybdenum steel is so fitted to the first half part of the internal circumference 22 of a large diameter in a case 20 for a cylinder lock C that it is incapable of moving in the axial direction in a turnable manner. Even if a key-hole is cut by drill, etc., to break, boring can not be done and, at the same time, even if impact is applied thereto by hammer, etc., it is protected from breakage. A conventional locking and unlocking is so made by inserting a key into the key hole provided to the hard cover 35 to turn, and the hard cover 35 is not required to remove. By the constitution, the lock having high resistance force against not only cutting breaking but also against impulsive breaking can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a destruction-prevention type cylinder lock for preventing a malicious unlocking operation in which a front surface of a cylinder lock is cut and broken or a hammer hits to break the table.

[0002]

2. Description of the Related Art Cylinder locks can be easily locked and unlocked by using a regular key, and cannot be unlocked with a key having a different code, thereby preventing theft. Therefore, cylinder locks are widely used in all fields. I have. However, in general cylinder locks, a thief without a key uses a drill tool to cut from the front of the cylinder lock, and cuts the tumbler pin inside the plug with the keyhole to crush the locking function, or to use the cylinder lock shear line. At the same time, it is impossible to prevent malicious crimes such as crushing the locking function by cutting a driver pin or pulling out a plug with a tapping screw and illegally unlocking by cutting.

In order to prevent such cutting breakage, there is a cylinder lock of a type in which the front surface of a cylinder lock is covered with a high-hardness material having a surface hardness that cannot be cut with the cutting edge of a drill tool, thereby preventing cutting breakage by a drill ( 58-9
944 and Japanese Utility Model Publication No. 60-28750).

A cylinder lock A described in Japanese Utility Model Publication No. Sho 56-48845, as shown in a vertical sectional view of FIG. 7, is provided with a fitting step 2 on a front surface of a soft case 1 and is made of a high hardness material. The protective body 3 is attached to the fitting step 2 and fixed with the pins 4. A protective body 6 made of a high-hardness material is inserted into the protective body 3 in front of the soft plug 5, and the rear end of the protective body 6 is inserted. And the engaging projections 8 provided at the front end of the plug 5 are engaged with the engaging portions 7 provided at the front end of the plug 5. The protective members 3 and 6 are formed of a drill material (tool steel, high-speed steel). Hard quenching materials, ceramics, cemented carbides, etc. are used.

A lock protection device B described in Japanese Utility Model Publication No. Sho 60-28750 has a housing 1 as shown in a vertical sectional view of FIG.
The ring-shaped frame 12 is inserted into the hole 11 of the cylinder lock 11, and the cylinder lock 14 is inserted into the annular engagement projection 13 provided on the inner peripheral surface of the ring-shaped frame 12. A flange 16 provided on the outer surface of the cylinder lock 14, and a nut 16 is screwed into a male screw provided on the outer peripheral surface of the cylinder lock 14. The rotary member 17 and the cylinder lock 14 that are in contact with the front surface of the cylinder lock 14 are covered with a protective member 19 having a hole 18 having a diameter larger than the keyhole at the center. Since the protection member 19 and the rotating member 17 have a hardness that cannot be broken by cutting with a drill, the cylinder lock 14 is protected.

[0006]

High-hardness materials generally have low toughness, and ceramics and cemented carbides have extremely high hardness, but are easily cracked by impact. There is a drawback that the impact is destroyed when the impact is applied by a hammer directly or with a hammer. The quenched material is harder to break than ceramics and cemented carbide, but may be broken by impact. Therefore, the cylinder lock A shown in FIG. 7 and the lock protection device B shown in FIG. 8 can prevent cutting breakage by a drill tool, but cannot prevent impact breakage by a hammer or the like.

[0007] In the cylinder lock A shown in FIG. 7, when the protective body 3 is cracked into two or three blocks due to impact destruction, the protective body 3 drops off from the fitting step portion 2, and the protective body 6 is dropped by the protective body 3 falling off. Since the hard material is dropped, the high-hardness material is lost, and there is a possibility that the material is broken by a drill. In the lock protection device B shown in FIG. 8 as well, if the protection member 19 cracks into a few blocks due to impact destruction, the protection member 19 falls off the outer peripheral surface of the frame 12 and the rotating member 17 also falls, so There is no durable material, and there is a risk of cutting and breaking by the drill. An object of the present invention is to provide a destruction-prevention type cylinder lock capable of preventing cutting breakage by a drill without dropping of the high-hardness material even if the high-hardness material cracks. .

[0008]

In order to achieve the above-mentioned object, in the destruction-prevention type cylinder lock of the present invention, a plug having a keyhole opening at the front is inserted into the inner peripheral surface of a cylindrical case. Then, in a cylinder lock in which the plug is rotatable when a key is inserted into the keyhole, a hard cover having a high hardness surface that does not accept a tool edge is rotated to a front end portion of an inner peripheral surface of the case. Possible, axially immovably inserted, a through hole intersecting the key hole is provided at the contact surface between the hard cover and the plug, and a key way base having a higher hardness than the plug is inserted into the through hole, and the key is inserted. A key insertion hole overlapping the key hole of the plug is provided in the way base and the hard cover, and a front surface of the plug is covered and protected by the hard cover accommodated in a front end portion of the case. Also It is.

The material of the hard cover is a special steel whose hardenability is guaranteed, and the front surface of the hard cover is preferably hardened by quenching so as not to accept drilling. A steel ball insertion hole intersecting at a right angle to the through hole is provided on a contact surface between the hard cover and the plug, and a steel ball having a high hardness surface is rotatably accommodated in the steel ball insertion hole. Can be. The keyhole is eccentric to one side with respect to the axis of the plug, and a steel ball insertion hole is provided on the other side. The steel ball insertion hole can rotatably accommodate a steel ball having a high hardness surface. . The keyway hole of the keyway base may be formed with a projection slidably engaged with a key groove provided in the key.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view of a break prevention cylinder lock, FIG. 2 is a sectional view taken along line XX of FIG. 1, and FIG. 1 is a front view of FIG. 1, FIG. 4 is a sectional view taken along line YY of FIG. 1, and FIG. 5 is a rear view of FIG. In the structure of the destruction prevention type cylinder lock C of the present invention, a large-diameter stepped portion 21 is formed at the front end of a cylindrical case 20, and a large-diameter inner peripheral surface is formed between the inner peripheral surface 20 a of the case 20 and the stepped portion 21. 2
2 are formed.

The structure of the case 20 will be described.
A plurality of driver pin holes 23, 24, 25 penetrating upward, downward, and laterally from 0 a are provided in the axial direction of the case 20, respectively. A dovetail-shaped groove 26 intersecting with the rows 24 and 25, respectively, and a cover 27 fitted in the groove 26 and closing each of the driver pin holes 23, 24 and 25, respectively.
(See FIGS. 1 and 2). Each driver pin hole 2
A driver pin 28 and a spring 29 that urges the driver pin 28 in a direction protruding from the inner peripheral surface 20a of the case 20 are inserted into 3, 24, and 25 (see FIGS. 1 and 2).

The plug 30 to be inserted into the case 20 is provided with a bulging portion 31 to be inserted into the rear half of the large-diameter inner peripheral surface 22 and a keyhole 32 opening at the tip end surface. Plug 3
When 0 is at an angle at which the key can be removed, a tumbler pin hole 33 communicating from the key hole 32 to each of the driver pin holes 23, 24, 25 is provided, and a tumbler pin 34 is inserted into each tumbler pin hole 33.

When the key is not inserted into the key hole 32, the plug 30 cannot be rotated because the driver pin 28 pressed by the spring 29 is engaged in the tumbler pin hole 33, and is pressed by the driver pin 28. One end of the tumbler pin 34 protrudes into the key hole 33. When a key is inserted into the key hole 32, the tumbler pin 34 pressed by the key pushes the driver pin 28, and the tumbler pin 34 and the driver pin 2
8 is the shear line of the cylinder lock C (plug 30
, The plug 30 can be rotated.

The hard cover 35 rotatably inserted into the front half of the large-diameter inner peripheral surface 22 is made of a special steel material, for example, a nickel-chromium molybdenum steel material, whose hardenability is guaranteed.
The tip surface has a high hardness due to quenching that does not accept cutting. The rear end surface of the hard cover 35 contacts the front end surface of the bulging portion 31 of the plug 30, and the large-diameter step portion 21
Is provided in the keyhole 3 of the plug 30.
2 is provided with a key insertion hole 37 (FIGS. 1, 2, and 3).
See FIG. 6).

An annular groove 41 is provided around the outer peripheral surface of the hard cover 35, and a retaining ring 42 inserted into the annular groove 41 engages with an annular groove 43 provided on the large-diameter inner peripheral surface 22 of the case 20 (see FIG. 2). (See FIG. 1). Therefore, the hard cover 35 is
0, which is rotatable inside the large-diameter inner peripheral surface 22 and cannot move in the axial direction.

The hard cover 35 has a hardened front surface to prevent cutting breakage caused by a drill. However, a material having high hardness generally has a property of being susceptible to impact breakage. There is a risk of cracking when subjected to violent vandalism. However, since the hard cover 35 is accommodated in the large-diameter inner peripheral surface 22, it is temporarily divided into two,
Even if a crack that causes division occurs, it does not fall out of the case 20. Therefore, the hard cover 35 protects the cylinder lock C against not only cutting breakage but also impact breakage.

A through hole 38 is provided at a contact surface between the hard cover 35 and the front end surface of the bulging portion 31 so as to intersect the key hole 32 at substantially right angles. A keyway base 39 having the same shape as the through hole 38 is provided. The keyway base 3 is inserted into the through hole 38.
9, a key insertion hole 40 overlapping the key hole 32 and the key insertion hole 37;
(See FIGS. 4 and 6). Keyway base 3
9 is a function that makes the cutting of the plug 30 more difficult,
The keyway base 39 has a role of a key for integrally rotating the plug 30, and in this embodiment, nickel chrome molybdenum steel is used.

A pair of projections 40a are provided in the key insertion hole 40 of the keyway base 39, and when a regular key is inserted, the projections 4a are formed in key grooves (not shown) provided on both sides of the key.
0a is slidably engaged. Since the projection 40a has a function of preventing insertion of a key whose key groove position and shape do not match, a key code of a cylinder lock is further added.

The bulge 3 of the hard cover 35 and the plug 30
1 are provided on both sides of the through hole 38 (the through hole 3 in FIG. 6).
The steel ball insertion hole 44 is provided in the keyway base 39 at a position overlapping the steel ball insertion hole 44, and a steel ball insertion hole is provided in the keyway base 39. A part of a steel ball 46 rotatably inserted into 44 engages with the concave portion 45. The steel ball 46 protects an area of the plug 30 where the keyway base 39 is not provided.
In this embodiment, a steel ball 42 made of cemented carbide is used, but a material whose surface is hardened by quenching may be used.

Since the keyhole 32 of the plug 30 is deviated to one side with respect to the center of the plug 30, the keyway base 3
Nine key insertion holes 40 are also located at positions deviated to one side. Accordingly, a steel ball insertion hole 47 with a bottom is provided in the other side of the keyway base 39, and a steel ball 48 of a cemented carbide is rotatably inserted into the steel ball insertion hole 47 to prevent cutting of the keyway base 39. The effect can be further enhanced (see FIG. 6).

Next, a description will be given of the effect of the above-structured destruction prevention type cylinder lock against cutting and impact destruction. The surface of the hard cover 35 has a high hardness that does not accept cutting, and the diameter of the hard cover 35 is larger than the diameter of the shear line of the cylinder lock C.
2 and the shear line are prevented from being broken by a drill and losing the locking function.

Even if the hard cover 35 is drilled, the hard cover 35 and the steel balls 46, 48
Block the drilling of the drill, so that the cylinder lock C is further protected from cutting. When hitting the surface of the hard cover 35 with a chisel and hitting it with a hammer, the hard cover 3
5 is hardened only because the surface is hardened and the inside has toughness. However, even if the impact of the hammer is extremely large and the hard cover 35 is cracked,
5 cannot be easily removed because it is accommodated in the large-diameter inner peripheral surface 22 while being cracked and is restrained.

Since the hard cover 35 and the keyway base 39 having the steel ball insertion hole 47 and the projection 40a are formed separately, the manufacture is easy, and the keyway base in which the position and the shape of the projection 40a are changed. By exchanging 39, it is possible to change to a cylinder lock with a different key code.

[0024]

Since the present invention is configured as described above, it has the following effects. (1) The conventional cutting fracture prevention type cylinder lock has a weak point against impact destruction using a hammer or the like, but the destruction prevention type cylinder lock of the present invention not only prevents cutting destruction, It has great resistance to impact fracture. (2) Even if the hard cover is cracked with an extremely large impact breaking force, the hard cover is housed in the case and is restrained, so it cannot be easily removed, and it is extremely difficult to break the impact.

[Brief description of the drawings]

FIG. 1 is a vertical cross-sectional view of a break prevention cylinder lock.

FIG. 2 is a sectional view taken along line XX of FIG.

FIG. 3 is a front view of FIG. 1;

FIG. 4 is a sectional view taken along line YY of FIG. 1;

FIG. 5 is a rear view of FIG. 1;

FIG. 6 is a perspective view of a plug, a hard bar, and components attached thereto.

FIG. 7 is a longitudinal sectional view showing a conventional example of a cutting fracture prevention type cylinder lock.

FIG. 8 is a longitudinal sectional view showing a conventional example of a lock protection device of a cutting breakage prevention type.

[Explanation of symbols]

 C Destruction prevention type cylinder lock 20 Case 21 Step 22 Large diameter inner peripheral surface 31 Swelling portion 32 Key hole 35 Hard cover 37, 40 Key insertion hole 38 Through hole 39 Keyway base 40a Projection 44, 47 Steel ball insertion hole 46 , 48 steel ball

Claims (5)

[Claims] 1. A cylinder lock in which a plug having a keyhole opening in a front surface is inserted into an inner peripheral surface of a cylindrical case, and the plug is rotatable when a key is inserted into the keyhole. In the above, a hard cover having a surface of high hardness is inserted into the front end portion of the inner peripheral surface of the case so as to be rotatable and immovable in the axial direction, and a through hole intersecting the keyhole is formed in a contact surface between the hard cover and the plug. A keyway base having a higher hardness than the plug is inserted into the through hole, and a key insertion hole overlapping the keyhole of the plug is provided in the keyway base and the hard cover. A destruction-preventive cylinder lock, which is covered and protected by the hard cover accommodated in a front end portion of a case. 2. The material of the hard cover is a special steel, and the front surface of the hard cover has a hardness that does not allow cutting of a drill by quenching.
Destruction prevention type cylinder lock as described. 3. The contact surface between the hard cover and the plug,
3. A steel ball insertion hole intersecting at a right angle to the through hole, and a steel ball having a high hardness surface is rotatably accommodated in the steel ball insertion hole. Destruction prevention type cylinder lock. 4. The keyhole is eccentric to one side with respect to the axis of the plug, and a steel ball insertion hole is provided in the other, and a steel ball having a high hardness surface is rotatable in the steel ball insertion hole. The destruction-prevention type cylinder lock according to claim 1, wherein the cylinder lock is housed. 5. The keyway-based key insertion hole,
The destruction-prevention type cylinder lock according to claim 1, 2, 3, or 4, wherein a projection slidably engaged with a key groove provided in the key is formed.