An internally extendable lock cylinder

Abstract

This case relates to an extendable lock cylinder, comprising a lock cylinder body, characterized in that: the lock cylinder body includes a crossbeam integrally formed and lock shells detachably connected to both sides of the crossbeam, with a lever between the two lock shells; each lock shell contains a lock cylinder; a lock cylinder extension is detachably connected between the lever and one of the lock shells; the lock cylinder extension includes a lock shell extension and a lock cylinder extension installed within the lock shell extension; a first limiting structure is provided between the lock cylinder extension and the lever; a second limiting structure is provided between the lock cylinder extension and the lock cylinder; and a fastening structure is provided between the lock shell extension and the lock shell. The lock cylinder body adopts a detachable connection design between the crossbeam and the two lock shells, facilitating assembly and disassembly. Through the cooperation of the first limiting structure, the second limiting structure, and the fastening structure, a rigid connection and synchronous transmission between the lock cylinder extension and the original lock cylinder body are achieved. This solves the problem of adapting to thick door panels and improves stability and security.

Description

Technical Field

[0001] This utility model relates to the field of locks, specifically to a lock cylinder that can be internally extended. Background Technology

[0002] In the installation and application of mechanical lock cylinders, the diversity of door panel thickness has always been a key issue restricting the compatibility of lock cylinders. In existing technologies, for thick door panel scenarios, the solution of extending the lock cylinder is usually adopted, that is, adding an extension component at one or both ends of the lock cylinder to extend the overall length.

[0003] For example, Chinese utility model patent CN222207499U, published on December 2, 2024, discloses an adjustable length lock cylinder. The adjustable length lock cylinder includes a lock cylinder body, which comprises a lock shell, a lock cylinder, and a lock cylinder pivot. The lock cylinder has a keyhole for key insertion, and the lock cylinder pivot has a connecting mechanism for manual or electric unlocking. The lock cylinder is characterized by further including a first lock shell extension and a lock cylinder extension, which are detachably disposed on the lock cylinder body. At the end for key insertion, the lock housing has a first fixing part for fixing the first lock housing extension. The first fixing part includes a fixing groove and a fixing hole. The first lock housing extension has a plug that mates with the fixing groove and a fixing post that mates with the fixing hole. At the end of the lock cylinder body for key insertion, the lock cylinder has a recessed hole for fixing the lock cylinder extension. The lock cylinder extension has a protruding post that mates with the recessed hole. The first lock housing extension has an mounting hole for placing the lock cylinder extension.

[0004] As mentioned above, existing extended structures often rely on complex splicing designs, using bolts and snap-fit ​​mechanisms to fix the extended sections at both ends of the lock cylinder. This necessitates simultaneous adjustment of the fit and precision of multiple components during installation, making the process cumbersome and time-consuming. More importantly, the connection strength between this extended structure with exposed ends and the original lock cylinder body is insufficient. Especially during frequent unlocking operations, the connection is prone to loosening and displacement due to uneven stress, directly affecting the stability of the lock cylinder's transmission. This can even lead to malfunctions such as lock cylinder jamming and the inability to insert or remove the key, severely shortening the lifespan of the lock cylinder.

[0005] On the other hand, the extended components exposed on both sides of the lock cylinder, due to their proximity to the door panel, become a weak point in the lock's security. Criminals can damage the connection between the extended section and the original lock cylinder through forceful prying or cutting, or directly destroy the internal transmission structure of the extended section, thereby breaching the lock cylinder's defenses. This design, with its exposed structure and poor protection, significantly reduces the overall security level of the lock, failing to meet the needs of high-end security scenarios.

[0006] Therefore, overcoming the aforementioned shortcomings has become an important issue that urgently needs to be addressed by those skilled in the art. Utility Model Content

[0007] This invention overcomes the shortcomings of the above-mentioned technologies and provides a lock cylinder that can be internally extended.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] An extendable lock cylinder includes a lock cylinder body, characterized in that: the lock cylinder body includes a crossbeam integrally formed and lock shells detachably connected to both sides of the crossbeam, a lever is provided between the two lock shells, a lock cylinder is installed in each of the two lock shells, a lock cylinder extension component is detachably connected between the lever and one of the lock shells, the lock cylinder extension component includes a lock shell extension component and a lock cylinder extension component installed in the lock shell extension component, a first limiting structure is provided between the lock cylinder extension component and the lever, a second limiting structure is provided between the lock cylinder extension component and the lock cylinder, and a fastening structure is provided between the lock shell extension component and the lock shell.

[0010] Furthermore, the first limiting structure includes a first boss disposed on the lever sleeve and a first groove disposed on the lock cylinder extension member facing the lever sleeve side. The first boss is inserted into the first groove, and a first protruding strip extends outward from the side wall of the first boss. A first slot for the first protruding strip to be engaged is provided on the groove wall of the first groove.

[0011] Furthermore, the second limiting structure includes a second boss disposed on the lock cylinder extension member facing the lock cylinder side and a second groove disposed on the lock cylinder facing the lock cylinder extension member side. The second boss is inserted into the second groove, and a second protruding strip extends outward from the side wall of the second boss. A second slot for the second protruding strip to be inserted is provided on the groove wall of the second groove.

[0012] Furthermore, the fastening structure includes a first pin hole formed on the lock housing extension, a second pin hole provided on the lock housing, and a first pin passing through the first pin hole and connected to the second pin hole.

[0013] Furthermore, the first pin includes a pin head, a central shaft connected to the lower end of the pin head, and a pin rod connected to the end of the central shaft. A limiting surface for limiting the pin head is formed in the first pin hole. The pin head is sunk into the first pin hole and connected to the second pin hole.

[0014] Furthermore, the outer wall surface of the lock cylinder extension is provided with a length indicator mark.

[0015] Furthermore, the crossbeam includes a central column and connecting columns symmetrically arranged at both ends of the central column.

[0016] Furthermore, the central column is provided with symmetrical first screw holes, and the lock housing is provided with second screw holes. A bolt that passes through the first screw hole and connects to the second screw hole is installed in the first screw hole.

[0017] Furthermore, the lock housing has a connecting hole for the connecting pin to pass through, and the lock housing also has an installation hole that communicates with the connecting hole. The connecting pin has a connecting groove, and an I-shaped pin is installed in the installation hole. The I-shaped pin has an annular groove recessed in the middle. A hooking part is formed between the connecting pin and the connecting groove for engaging with the annular groove.

[0018] Compared with the prior art, the beneficial effects of this utility model are:

[0019] This invention provides an internally extendable lock cylinder. By placing the extended portion of the lock cylinder between the lock housing and the latch, the extended portion is positioned relatively in the middle of the door panel during installation, avoiding the stability and security risks associated with exposed connections. The lock cylinder body adopts a detachable connection design between the crossbeam and the two sides of the lock housing, facilitating easy assembly and disassembly. By adding a concealed lock cylinder extension between the latch and the lock housing, along with a first limiting structure, a second limiting structure, and a fastening structure, a rigid connection and synchronous transmission between the extended portion and the original lock cylinder body are achieved. This solution not only solves the compatibility problem with thick door panels but also improves structural stability and security performance through internal integration, while remaining convenient for assembly and disassembly. Attached Figure Description

[0020] Figure 1 This is an exploded view of the overall structure of the lock cylinder body after the lock cylinder extension piece is assembled.

[0021] Figure 2 This is a schematic diagram of the mechanism in this case.

[0022] Figure 3 This is a structural schematic diagram of the extended lock cylinder component in this case.

[0023] Figure 4 This is a schematic diagram of the lock cylinder structure in this case.

[0024] Figure 5 This is a structural diagram of the extended lock housing and the first pin in this case.

[0025] Figure 6 This is a structural diagram of the lock shell in this case.

[0026] Figure 7 This is a structural diagram showing the connection state of the beam, bolts, and I-beams in this case.

[0027] Figure 8 This is a 3D view of the lock cylinder body in its unextended state, as well as schematic diagrams of lock cylinder extensions and crossbeams of different lengths. Detailed Implementation

[0028] The following examples provide a more detailed description of the features and other related characteristics of this utility model, to facilitate understanding by those skilled in the art:

[0029] like Figures 1 to 8 As shown, this invention provides an extendable lock cylinder, including a lock cylinder body 100. The lock cylinder body 100 includes a crossbeam 1 integrally formed and lock shells 2 detachably connected to both sides of the crossbeam 1. In specific implementation, the crossbeam 1 is integrally formed and made of metal material, preferably stainless steel. The crossbeam 1 needs to be heat-treated and then electroplated to further enhance its hardness and tensile strength. The integrally formed crossbeam 1 facilitates manufacturing, greatly saves manufacturing costs, and is conducive to mass production. In addition, the integral design greatly reduces the number of parts, enhances the tensile strength of the crossbeam 1 and the lock cylinder as a whole, and makes disassembly and assembly more time-saving and labor-saving. Secondly, the detachable connection between the crossbeam 1 and the lock shell 2 facilitates the disassembly and assembly of the crossbeam 1 and the lock shell 2 when it is necessary to extend the lock cylinder body 100. A latch 3 is provided between the two lock shells 2, and a lock cylinder 4 is installed in each of the two lock shells 2. A lock cylinder extension component 5 is detachably connected between the latch sleeve 3 and one side of the lock housing 2. The lock cylinder extension component 5 includes a lock housing extension component 51 and a lock cylinder extension component 52 installed inside the lock housing extension component 51. That is to say, the lock cylinder provided in this case can be extended in two ways: one side of the latch sleeve 3 or both sides, which provides better matching and adaptability to door panel thickness and better adjustability. A first limiting structure is provided between the lock cylinder extension component 52 and the latch sleeve 3, a second limiting structure is provided between the lock cylinder extension component 52 and the lock cylinder 4, and a fastening structure is provided between the lock housing extension component 51 and the lock housing 2. The combined action of the first and second limiting structures ensures that even after the extended lock cylinder 5 is extended, the cylinder 4 can still be rotated to drive the lever 4, effectively guaranteeing the connection stability between the extended lock cylinder 52, the cylinder 4, and the lever 3. The fastening structure ensures the connection stability between the extended lock shell 51 and the lock shell 2, thereby guaranteeing the stable transmission, low failure rate, and long service life of the lock cylinder in this case.

[0030] In this case, the lock cylinder extension is preferably available in lengths of 5mm, 10mm, 15mm, and 20mm. It should be noted that in practical implementation, the length of the crossbeam 1 is matched to the length of the lock cylinder extension 5 in appropriate quantities, allowing users to disassemble the crossbeam 1 to extend the lock cylinder extension 5 themselves. That is to say, the lock cylinder in this case will be shipped with crossbeams 1 and lock cylinder extensions 5 of corresponding sizes, and the corresponding quantities will be provided. In the unextended state, the crossbeam 1 is preferably 60mm in length, and the available lengths of the extended crossbeam 1 are preferably 70mm, 80mm, 90mm, and 100mm. Users can also selectively design lock cylinder extensions 5 and crossbeams 1 of different lengths according to their actual needs, and are not limited to this, but the dimensions provided in this case are sufficient to meet the needs of extended lock cylinders on the market.

[0031] Specifically, such as Figures 1-3 As shown, the first limiting structure includes a first boss 31 disposed on the lever sleeve 3 and a first groove 521 disposed on the lock cylinder extension member 52 facing the lever sleeve 3. The first boss 31 is inserted into the first groove 521. A first protrusion 311 extends outward from the side wall of the first boss 31. A first slot 5211 is provided on the groove wall of the first groove 521 for the first protrusion 311 to be inserted.

[0032] As described above, this invention achieves dual limiting between the extended lock cylinder component 52 and the lever sleeve 3 through the aforementioned structure, effectively solving the problem of relative movement between the extended component and the original component in the prior art. Even under high-frequency vibration or forceful operation, the extended lock cylinder component 52 and the lever sleeve 3 maintain synchronous rotation, avoiding unlocking failure or jamming due to loosening, resulting in high stability. The guiding effect of the first boss 31 and the first groove 521 allows for quick alignment of the extended lock cylinder component 52 during installation. Combined with the guiding positioning and circumferential limiting effect of the first protrusion 311 and the first slot 5211, the initial connection and fixation of the extended lock cylinder component 52 and the lever sleeve 3 can be completed without tools, making assembly and disassembly convenient, saving time and effort.

[0033] In practical implementation, to ensure a more stable connection between the lock cylinder extension piece 52 and the lever sleeve 3, and to stabilize their circumferential positioning, thus guaranteeing stable transmission, preferably, two first protrusions 311 can be provided. For quick matching and extension operations, and to prevent incorrect positioning, three first protrusions 311 can also be provided. Correspondingly, the number of first slots 5211 should match the number of first protrusions 311. For example, to accommodate high-torque lock cylinders, a greater number of first slots 5211 can be provided to cooperate with the first protrusions 311 for better results.

[0034] like Figures 1-4As shown, the second limiting structure of this case includes a second protrusion 522 disposed on the lock cylinder extension 52 facing the lock cylinder 4 and a second groove 41 disposed on the lock cylinder 4 facing the lock cylinder extension 52. The second protrusion 522 is inserted into the second groove 41. A second protrusion 5221 extends outward from the side wall of the second protrusion 522. A second slot 411 is provided on the groove wall of the second groove 41 for the second protrusion 5221 to be inserted.

[0035] As mentioned above, similarly, the function, principle, and effect of the second limiting structure in this case can be understood by referring to the description of the first limiting structure in the previous text of this case, and will not be repeated here.

[0036] Specifically, such as Figure 1 , Figure 5 , Figure 6 As shown, the fastening structure includes a first pin hole 511 on the lock housing extension 51, a second pin hole 21 on the lock housing 2, and a first pin 6 passing through the first pin hole 511 and connected to the second pin hole 21. The first pin 6 connects the lock housing extension 51 and the lock housing 1 through the first pin hole 51, forming a rigid fixation that ensures no relative displacement between the two in the axial and circumferential directions. Together with the first limiting structure and the second limiting structure, it forms a stable support system after the lock cylinder is extended, which is simple, reliable, and easy to assemble and disassemble.

[0037] Continue to refer to Figure 1 , Figure 5 , Figure 6 As shown, the first pin 6 further includes a pin head 61, a central shaft 62 connected to the lower end of the pin head 61, and a pin rod 63 connected to the end of the central shaft 62. A limiting surface 5111 for limiting the pin head 61 is formed in the first pin hole 511. The pin head 61 is recessed into the first pin hole 511 and connected to the second pin hole 21.

[0038] In other words, the first pin 6 has a three-tiered stepped structure. This three-tiered structure increases the tensile strength between the lock housing extension 51 and the lock housing 2, avoids stress concentration, and improves connection strength and stability. The diameter of the pin head 61 is larger than the diameter of the central shaft 62, and the diameter of the central shaft 62 is larger than the diameter of the pin shank 63. The pin head 61 of the first pin 6 is confined in the first pin hole 511 by the limiting surface 5111, bearing axial tensile force, while effectively preventing the pin shank 63 from being over-inserted into the second pin hole 21, making installation more accurate and faster.

[0039] like Figure 1 , Figure 8 As shown, furthermore, to facilitate users in quickly selecting accessories of suitable length to extend the lock cylinder and save modification time, a length indicator mark 53 is provided on the outer wall of the lock cylinder extension part 5. In specific implementation, a length indicator mark is also provided on the outer wall of the crossbeam 1.

[0040] Reference Figure 1 , Figures 6-8 As shown, specifically, the crossbeam 1 includes a central column 11 and connecting columns 12 symmetrically arranged at both ends of the central column 11. First screw holes 111 are symmetrically formed on the central column 11, and second screw holes 22 are formed on the lock housing 2. Bolts 7, passing through the first screw hole 111 and connecting to the second screw hole 22, are installed in the first screw hole 111. This method of connecting and fixing the lock housings 2 at both ends with two bolts 7 is simple to manufacture, easy to assemble and disassemble, low in cost, and provides high connection strength.

[0041] Continue to refer to Figure 1 , Figures 6-8 As shown, the lock housing 2 further includes a connecting hole 23 for the connecting post 12 to pass through, and a mounting hole 24 communicating with the connecting hole 23. The connecting post 12 has a connecting groove 121, and an I-shaped pin 8 is installed in the mounting hole 24. The I-shaped pin 8 has an annular groove 81 recessed in the middle. A hooking part 122 is formed between the connecting post 12 and the connecting groove 121 for engaging with the annular groove 81.

[0042] Because the bolts 7 connecting the fixed crossbeam 1 and the lock housing 2 are connected to the central post 11, which is usually installed in the very center of the door panel, making it more concealed and generally requiring significant damage to the door panel to be discovered, illegal damage is more difficult. However, when the user needs to extend the lock cylinder, it should not affect the user's ease of disassembly and assembly. This is because directly connecting the two ends of the crossbeam 1 by drilling holes in the connecting posts 12 and then using pins or screws has certain drawbacks. First, disassembly and assembly are inconvenient. Second, because the lock cylinder is internally extended, its sides are more exposed relative to the door panel. Criminals can easily damage the door panel slightly to see the pins or screws used to connect the crossbeam 1. At this point, criminals can easily use tools to remove the pins and screws, destructively disassembling the lock cylinder, separating the lock housing 2 from the crossbeam 1, damaging the internal parts of the lock cylinder, and illegally unlocking it. Because common pins are typically cylindrical with a uniform cross-section, they go straight in and out of the hole, making them easy to drive out using a tool. Additionally, screw-locking methods often lack sufficient tensile strength, making it easier for beam 1 to be pulled out.

[0043] Therefore, in this embodiment, an unconventional pin and an unconventional I-shaped pin 8 with an annular groove 81 are used in conjunction with the hook part 122 of the connecting groove 121 on the connecting post 12 to solve the above-mentioned technical problems. This makes disassembly and assembly convenient and ensures good safety.

[0044] In practical implementation, an I-shaped groove is formed on the I-pin 8 by the cooperation of the annular groove 81 and the two ends of the annular groove 81. Through the contact transmission of force between the I-shaped groove and the hook part 122, the tensile strength between the crossbeam 1 and the lock shell 2 is effectively improved. At the same time, it is convenient to engage with the connecting groove 121. The I-shaped groove is engaged with the wall of the connecting groove 121, preventing the situation where the conventional pin is easily damaged when it goes straight in and out. This structure requires first removing the fastening bolt 7 on the central column 11, then pulling the lock shell 2 outward to pull the annular groove 81 of the I-pin 8 out of the hook part 122 on the connecting column 12, and then disassembling the I-pin 8. Since the bolts 7 that fasten the crossbeam 1 and the lock shell 2 are connected to the central column 11, and the central column 11 is generally installed in the center of the door panel, it is more concealed and usually requires a large amount of damage to the door panel to be discovered. Therefore, illegal damage is more troublesome. When the user needs to extend the lock cylinder, it is more convenient to remove and install it. This forms a dual advantage of being difficult to damage from the outside and easy to disassemble and install from the inside.

[0045] As stated above, this case protects a lock cylinder that can be internally extended. All technical solutions that are the same as or similar to this case should be considered to fall within the scope of protection of this case.

Claims

1. A lock cylinder that can be internally extended, comprising a lock cylinder body (100), characterized in that: The main body of the lock cylinder (100) includes a crossbeam (1) integrally formed and lock shells (2) detachably connected to both sides of the crossbeam (1). A lever (3) is provided between the two lock shells (2). A lock cylinder (4) is installed in both lock shells (2). A lock cylinder extension (5) is detachably connected between the lever (3) and one of the lock shells (2). The lock cylinder extension (5) includes a lock shell extension (51) and a lock cylinder extension (52) installed in the lock shell extension (51). A first limiting structure is provided between the lock cylinder extension (52) and the lever (3). A second limiting structure is provided between the lock cylinder extension (52) and the lock cylinder (4). A fastening structure is provided between the lock shell extension (51) and the lock shell (2).

2. The lock cylinder that can be internally extended according to claim 1, characterized in that: The first limiting structure includes a first boss (31) disposed on the lever sleeve (3) and a first groove (521) disposed on the lock cylinder extension piece (52) facing the lever sleeve (3). The first boss (31) is inserted into the first groove (521). A first protrusion (311) extends outward from the side wall of the first boss (31). A first slot (5211) is provided on the groove wall of the first groove (521) for the first protrusion (311) to be inserted.

3. The lock cylinder that can be internally extended according to claim 1, characterized in that: The second limiting structure includes a second boss (522) disposed on the lock cylinder extension (52) facing the lock cylinder (4) and a second groove (41) disposed on the lock cylinder (4) facing the lock cylinder extension (52). The second boss (522) is inserted into the second groove (41). A second protrusion (5221) extends outward from the side wall of the second boss (522). A second slot (411) is provided on the groove wall of the second groove (41) for the second protrusion (5221) to be inserted.

4. The lock cylinder that can be internally extended according to claim 1, characterized in that: The fastening structure includes a first pin hole (511) opened on the lock case extension (51), a second pin hole (21) provided on the lock case (2), and a first pin (6) passing through the first pin hole (511) and connected to the second pin hole (21).

5. A lock cylinder that can be internally extended according to claim 4, characterized in that: The first pin (6) includes a pin head (61), a central shaft (62) connected to the lower end of the pin head (61), and a pin rod (63) connected to the end of the central shaft (62). A limiting surface (5111) for limiting the pin head (61) is formed in the first pin hole (511). The pin head (61) is sunk into the first pin hole (511) and the pin head (61) is connected to the second pin hole (21).

6. The lock cylinder that can be internally extended according to claim 1, characterized in that: The lock cylinder extension component (5) has a length indicator mark (53) on its outer wall surface.

7. A lock cylinder that can be internally extended according to any one of claims 1-6, characterized in that: The crossbeam (1) includes a central column (11) and connecting columns (12) symmetrically arranged at both ends of the central column (11).

8. A lock cylinder that can be internally extended according to claim 7, characterized in that: The central column (11) is symmetrically provided with a first screw hole (111), and the lock shell (2) is provided with a second screw hole (22). A bolt (7) is installed in the first screw hole (111) and passes through the first screw hole (111) and is connected to the second screw hole (22).

9. A lock cylinder that can be internally extended according to claim 8, characterized in that: The lock housing (2) is provided with a connecting hole (23) for the connecting post (12) to pass through. The lock housing (2) is also provided with a mounting hole (24) that communicates with the connecting hole (23). The connecting post (12) is provided with a connecting groove (121). An I-pin (8) is installed in the mounting hole (24). The I-pin (8) is provided with an annular groove (81) in the middle of its circumferential recess. A hooking part (122) is formed between the connecting post (12) and the connecting groove (121) for hooking with the annular groove (81).

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