A device for assembling plastic closures

Abstract

The utility model relates to a device for assembling plastic seal, including first handle, second handle, briquet, linkage and steel punch. First handle one end is equipped with forceps head, second handle front end is hinged with first handle front end. Briquet is slidably arranged on the forceps head and is equipped with mounting hole. Linkage connects second handle and briquet, and converts handle closing action into briquet linear motion towards forceps head. Steel punch is detachably installed in mounting hole and is equipped with elastic locking part for locking. Through linkage and elastic locking structure, the device realizes efficient synchronization of seal pressing and identification stamping, ensures stable stamping pressure and clear pattern. Steel punch supports hand-free quick replacement and firm locking, improves operation flexibility and management efficiency. The overall structure is simple and solid, reduces failure rate and maintenance difficulty, has low manufacturing cost and is easy to popularize.

Description

Technical Field

[0001] This utility model relates to the field of sealing technology, and more specifically, to a device for assembling plastic seals. Background Technology

[0002] Plastic seals, as inexpensive, effective, and easily identifiable tamper-evident sealing devices, are widely used in logistics transportation, container customs sealing, electricity metering instruments, air freight, and various scenarios requiring the integrity of goods or equipment. Their basic structure typically includes a plastic body with a pre-defined fracture structure and a metal or high-strength plastic locking wire running through it. During installation, the ends of the locking wire are passed through the locking lugs or holes of the object being sealed, then inserted into the plastic body. Finally, pressure is applied to lock the internal mechanism in place, leaving an irreversible embossed mark on the outside to indicate the sealing status and responsible party. The clarity, consistency, and anti-counterfeiting properties of this final embossed mark are core indicators of seal effectiveness, usually relying on a steel stamp with a specific code, symbol, or company logo imprinted on the surface of the plastic seal. Therefore, the efficiency of the plastic seal assembly tool directly affects the efficiency, reliability, and cost of the sealing operation.

[0003] For a long time, the assembly process in this field has evolved from relying entirely on simple hand tools to the emergence of specialized equipment. However, existing technologies still have a series of shortcomings that urgently need to be addressed in terms of ease of operation, functional integration, steel stamp management, and consistency of imprinting quality. In the earliest operating mode, operators typically needed to carry two separate tools: a special clamp for finally locking the plastic body to the locking thread, and a separate steel stamp and a hammer or mallet for striking the stamp. The operation process was cumbersome and required a high level of skill from the operator. First, the clamp was used to lock the mechanical parts of the seal. Then, the steel stamp was held and aligned with the imprinting area on the seal surface. Finally, the hammer in the other hand was used to strike the end of the steel stamp, thus creating an indentation mark on the plastic surface. This step-by-step operation was not only inefficient, but more seriously, the imprinting quality was extremely unstable. The force of the strike and the perpendicularity of the angle depended entirely on the operator's technique and experience, which could easily lead to an imprint that was too shallow and unclear, difficult to identify, or an imprint that was too deep and even damaged the seal body. In complex working conditions such as low light, confined spaces, or high-altitude operations, accurately positioning and striking the steel stamp with one hand is particularly difficult, further reducing the reliability and safety of the operation. At the same time, carrying multiple tools increases the workload of on-site workers and the cost of tool management. As a critical identification object, the steel stamp is easily lost, damaged, or confused during repeated striking and carrying, which is extremely inconvenient for applications that require frequent changes to the markings.

[0004] To address the problems associated with separate tools, some specialized tools have emerged on the market that initially integrate pressing and stamping functions. These tools generally employ a pliers-like structure, using a handle to drive a movable pressure head, attempting to simultaneously perform mechanical locking of the seal and stamping in a single action. However, these early integrated tools have several design flaws. The complex linkage structure makes the tools prone to wear and damage after frequent use, and repairs often require disassembling multiple parts or even specialized tools, resulting in high maintenance costs. More importantly, the installation methods for the stamps in these tools are typically rudimentary and unreliable, commonly using direct thread tightening or simple set screws for side mounting. Threaded installations are prone to loosening or even stripping under repeated impact loads, causing the stamp to rotate slightly or sink during stamping, resulting in blurred, ghosted, or misaligned patterns, severely affecting the anti-counterfeiting effect. Set screw mounting, on the other hand, easily leaves clamping marks on the stamp surface, potentially damaging the stamp itself with prolonged use. Furthermore, replacing the stamp requires additional tools for tightening and loosening, a time-consuming process that cannot meet the needs of rapid on-site replacement. The ease and reliability of steel stamp replacement have become key bottlenecks restricting the practicality of these tools. Furthermore, the steel stamp components of such tools are often completely built-in, making it impossible for operators to visually verify the correctness of the currently installed steel stamp markings during operation, increasing the risk of using the wrong markings.

[0005] An ideal plastic stamping assembly device should simultaneously meet the following key requirements: First, it must provide a stable and reliable force transmission mechanism, ensuring that regardless of changes in the operator's grip strength, the final imprinting force applied to the stamp remains within a range that produces clear plastic deformation in the plastic without causing damage, thus achieving a high degree of consistency in imprinting quality. Second, the stamp installation and replacement mechanism must balance convenience and robustness, ensuring no relative movement between the stamp and the tool body during long-term high-load use, and that the replacement process requires no additional tools, can be safely completed by hand in seconds, and has clear features to prevent misinstallation or visual confirmation. Third, the overall structure of the tool should be simplified while fulfilling its functional requirements, reducing the number of vulnerable parts, lowering the wear risk of complex mechanisms, thereby improving the overall durability of the tool, making daily maintenance and troubleshooting simple and easy, and ultimately controlling the long-term operating costs of the tool.

[0006] As described in announcement number CN202507694U, a plastic sealing clamp includes two handles hinged at the front. A clamp head is hinged to the front end of one handle. The upper end of the clamp head has a sliding sleeve, and the lower end has a lower jaw. A sliding jaw is slidably fitted inside the sliding sleeve. A traction part extending rearwards from the lower part of the sliding jaw is provided, and the traction part is hinged to the front end of the other handle. A steel stamp mounting hole is provided at the lower end of the sliding jaw, and a locking screw is provided on the side of the steel stamp mounting hole. The rear end of the steel stamp can be inserted into the mounting hole and then locked using the locking screw. Although this achieves uniform force application, improving the quality of sealing and stamping, its complex structure results in high cost, difficult maintenance, and the inability to easily replace the steel stamp. Utility Model Content

[0007] The main purpose of this invention is to provide a device for assembling plastic seals that allows for easy replacement of steel stamps while maintaining low cost.

[0008] To solve the above-mentioned technical problems, this utility model proposes a device for assembling plastic seals, comprising: a first handle with a pliers head at one end; a second handle with its front end hinged to the front end of the first handle; a pressure block slidably disposed on the pliers head, the pressure block having a mounting hole for installing a steel stamp; a linkage mechanism connected between the second handle and the pressure block, for converting the closing action of the second handle relative to the first handle into a linear movement of the pressure block toward the pliers head; and a steel stamp detachably installed in the mounting hole of the pressure block, the steel stamp having an elastic locking component for locking the steel stamp in the mounting hole.

[0009] In the above technical solution, the linkage mechanism further includes: connecting rods disposed on both sides of the pressure block; and pressure rods disposed on both sides of the front end of the second handle, the pressure rods having elongated holes, and the connecting rods passing through the elongated holes.

[0010] In any of the above technical solutions, a sliding sleeve is provided on the pliers head, the pressure block is slidably disposed in the sliding sleeve, and the side wall of the sliding sleeve is provided with a clearance hole for the connecting rod to pass through.

[0011] In any of the above technical solutions, the elastic locking component further includes: a fixing hole disposed on the side of the steel stamp; a fixing block slidably disposed in the fixing hole; and a spring disposed between the fixing block and the steel stamp, for providing an elastic force to the fixing block to make it partially protrude out of the fixing hole; wherein, a button hole is correspondingly provided on the pressure block, and an operable button is provided in the button hole for pressing the fixing block to retract it, so as to release the locking of the steel stamp.

[0012] In any of the above technical solutions, furthermore, a protrusion and a groove structure that cooperate with each other are provided between the fixing block and the fixing hole to limit the sliding stroke of the fixing block.

[0013] In any of the above technical solutions, furthermore, a protrusion and a groove structure that cooperate with each other are provided between the button and the button hole to limit the sliding stroke of the button.

[0014] In any of the above technical solutions, the pressure rod is further characterized by an arc shape, with its convex surface facing away from the hinge axis between the first handle and the second handle.

[0015] In any of the above technical solutions, the lower end of the pliers head is provided with a positioning hole for positioning the plastic seal.

[0016] In any of the above technical solutions, further, the tail of the steel piercing extends from the upper end of the pressure block in the installed state.

[0017] In any of the above technical solutions, a limiting block is provided in the fixing hole to limit the maximum extension position of the fixing block, so that the outer end face of the fixing block is flush with the outer peripheral surface of the steel stamp when it is fully extended.

[0018] Beneficial effects: The steel stamp allows for quick and easy manual replacement and secure locking, improving operational flexibility and efficiency. Its simple overall structure reduces failure rate and maintenance difficulty, while its low manufacturing cost facilitates widespread application. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a schematic diagram of the structure of this utility model in its open state; Figure 3 This is a longitudinal cross-sectional structural diagram of the present invention; Figure 4 This is a cross-sectional structural diagram of the present invention. Figure 5 yes Figure 3 A schematic diagram of the structure of region A in the middle.

[0021] The annotations in the attached figures are explained as follows: 1. First handle; 11. Pliers head; 111. Sliding sleeve; 2. Second handle; 21. Pressure rod; 3. Pressure block; 31. Button; 4. Linkage mechanism; 41. Connecting rod; 5. Steel stamp; 51. Elastic locking component; 511. Fixing block; 512. Spring; 513. Limit stop. Detailed Implementation

[0022] Hereinafter, exemplary embodiments according to this application will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely a part of the embodiments of this application, and not all of the embodiments of this application. It should be understood that this application is not limited to the exemplary embodiments described herein. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model.

[0023] It should be noted that, as shown in this application and claims, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" do not specifically refer to the singular and may also include the plural. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of explicitly identified steps and elements, and these steps and elements do not constitute an exclusive list; the method or apparatus may also include other steps or elements.

[0024] If the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0025] In this utility model, unless otherwise explicitly specified and limited, the terms "connection," "fixing," etc., should be interpreted broadly. For example, "fixing" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0026] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0027] This invention proposes a device for assembling plastic seals.

[0028] The apparatus for assembling plastic seals according to this application will be described in detail below through the following embodiments.

[0029] Example 1: like Figure 1 , 2 As shown in Figure 3, this embodiment proposes a device for assembling plastic seals, comprising: a first handle 1, one end of which is provided with a pliers head 11; a second handle 2, the front end of which is hinged to the front end of the first handle 1; a pressure block 3, slidably disposed on the pliers head 11, the pressure block 3 having an mounting hole for installing a steel stamp 5; a linkage mechanism 4, connected between the second handle 2 and the pressure block 3, for converting the closing action of the second handle 2 relative to the first handle 1 into a linear movement of the pressure block 3 toward the pliers head 11; and a steel stamp 5, detachably installed in the mounting hole of the pressure block 3, the steel stamp 5 having an elastic locking member 51 for locking the steel stamp 5 in the mounting hole.

[0030] The device has a first handle 1 with a clamp head 11 at one end, and a second handle 2 with its front end hinged to the front end of the first handle 1, allowing the two handles to rotate relative to each other. A pressure block 3 is slidably mounted on the clamp head 11, and the pressure block 3 has a mounting hole for mounting a steel stamp 5. A linkage mechanism 4 is connected between the second handle 2 and the pressure block 3. When the second handle 2 closes relative to the first handle 1, the linkage mechanism 4 converts this rotational motion into a linear motion of the pressure block 3 toward the clamp head 11. The steel stamp 5 is detachably mounted in the mounting hole of the pressure block 3, and the elastic locking component 51 on the steel stamp 5 can lock the steel stamp 5 in the mounting hole, ensuring that the steel stamp 5 and the pressure block 3 remain relatively fixed.

[0031] In existing technologies, some assembly operations require the use of two separate tools for sealing and stamping, making the process cumbersome. Carrying multiple tools increases the workload and management costs for operators, and the steel stamp 5 is prone to loss, damage, or confusion during transport and use. Furthermore, the installation method of the steel stamp 5 on some integrated tools is unreliable; the stamp 5 may rotate or sink during stamping, resulting in blurred or misaligned stamped patterns. Replacing the steel stamp 5 requires additional tools, which is time-consuming. Additionally, the complex structure of existing integrated tools is prone to wear and damage after frequent use, making repairs difficult. Moreover, operators cannot visually verify the accuracy of the markings on the steel stamp 5 installed in the integrated tool.

[0032] This device integrates the first handle 1, the second handle 2, the pressure block 3, the linkage mechanism 4, and the steel stamp 5 into one unit, eliminating the need to carry multiple tools and reducing the workload and tool management costs for operators. The steel stamp 5 features a detachable design and a flexible locking component 51, allowing for installation and replacement without additional tools. This prevents the steel stamp 5 from rotating or sinking during use, ensuring clear and accurate imprinting patterns. The overall structure consists of mutually cooperating basic components, reducing complex connection structures, minimizing the possibility of wear or damage, and simplifying maintenance. The detachable design of the steel stamp 5 also allows operators to confirm the markings before installation, avoiding the use of incorrectly marked steel stamps.

[0033] Example 2: This embodiment is a further improvement based on Embodiment 1.

[0034] like Figure 1 , 2 As shown, in this embodiment, The linkage mechanism 4 connects the second handle 2 and the pressure block 3. It includes connecting rods 41 on both sides of the pressure block 3 and pressure rods 21 on both sides of the front end of the second handle 2. The pressure rods 21 are arc-shaped, with their convex surfaces facing away from the hinge axis of the first handle 1 and the second handle 2. The pressure rods 21 have elongated holes, and the end of the connecting rods 41 away from the pressure block 3 passes through the elongated holes. A sliding sleeve 111 is provided above the pliers head 11. The pressure block 3 is slidably assembled in the sliding sleeve 111. The side wall of the sliding sleeve 111 has clearance holes corresponding to the position of the connecting rods 41. After the connecting rods 41 pass through the clearance holes, they engage with the elongated holes of the pressure rods 21. When the operator holds the first handle 1 and the second handle 2 and closes them relative to each other, the second handle 2 rotates around the hinge axis, driving the pressure rods 21 on both sides of the front end to move synchronously. The pressure rods 21 generate driving force on the connecting rod 41 through the elongated hole. Since the connecting rod 41 is fixedly connected to the pressure block 3 and the pressure block 3 is limited by the sliding sleeve 111, the driving force will be converted into the linear movement of the pressure block 3 along the sliding sleeve 111 toward the pliers 11, thereby driving the steel stamp 5 installed in the mounting hole of the pressure block 3 to move synchronously toward the pliers 11, completing the stamping action.

[0035] In existing technologies, separate tools require separate sealing and imprinting operations, making the process cumbersome. The imprinting force and angle rely entirely on the operator's experience, easily leading to imprints that are too shallow or too deep, damaging the seal itself. Some integrated tools have complex linkage structures that are prone to wear or damage after frequent use. Repairs require disassembling multiple parts and even using specialized tools, resulting in high maintenance costs. Furthermore, the complex linkage structure cannot guarantee the stability of force transmission, making it difficult to maintain consistent imprinting quality.

[0036] The linkage mechanism 4, through the cooperation of the connecting rod 41, the pressure rod 21 with the elongated hole, the sliding sleeve 111, and the clearance hole, forms a simple force transmission structure. This structurally transforms the closing rotation of the second handle 2 into the linear motion of the pressure block 3, achieving simultaneous sealing and marking, eliminating the need for separate operations. The arc-shaped pressure rod 21 optimizes the force transmission path, ensuring that the force applied by the operator is evenly distributed on the pressure block 3, avoiding instability in force and angle, and guaranteeing consistent marking quality. The overall structure is composed of basic components, reducing complex connection nodes and the possibility of wear and damage. Maintenance only requires inspection or replacement of key components such as the connecting rod 41 and the pressure rod 21, making operation simpler.

[0037] Example 3: This embodiment is a further improvement based on any of the above embodiments.

[0038] like Figure 3 , 4 As shown in Figures 5 and 6, in this embodiment, A limiting block 513 is located inside the fixing hole on the side of the steel stamp 5, at the corresponding position between the fixing block 511 and the spring 512. One end of the spring 512 inside the fixing hole abuts against the bottom of the fixing hole, and the other end is connected to the fixing block 511, providing an outward elastic force to the fixing block 511. When it is necessary to remove the steel stamp 5, the operator presses the button 31 in the button hole of the pressure block 3. The button 31 pushes the fixing block 511 to slide into the fixing hole and compresses the spring 512. The limiting block 513 plays a limiting role during the sliding of the fixing block 511. When the spring 512 retracts to the corresponding stroke, the limiting block 513 abuts against the fixing block 511, preventing the fixing block 511 from moving further inward. This ensures that the outer end face of the fixing block 511 is flush with the outer peripheral surface of the steel stamp 5, so that there is no protruding structure on the outer peripheral surface of the steel stamp 5, and it can be smoothly removed from the mounting hole of the pressure block 3.

[0039] In the prior art, the fixing block 511 of some steel stamp 5 locking structures lacks effective travel restriction during retraction, which may result in insufficient or excessive retraction of the fixing block 511. When the fixing block 511 retracts insufficiently, its outer end face will protrude from the outer circumference of the steel stamp 5, causing friction and jamming with the inner wall of the mounting hole when the steel stamp 5 is removed, hindering the smooth removal of the steel stamp 5 and increasing the difficulty of operation. When the fixing block 511 retracts excessively, it may cause the spring 512 to be over-compressed and deformed, or cause the fixing block 511 to collide hard with the inner wall of the fixing hole, resulting in component wear and affecting the service life of the structure.

[0040] The limit stop 513, precisely positioned within the fixing hole, effectively controls the retraction stroke of the fixing block 511. When button 31 is pressed, the limit stop 513 ensures that when the spring 512 retracts to the corresponding state, the outer end face of the fixing block 511 is flush with the outer circumference of the steel stamp 5, preventing the fixing block 511 from protruding or excessively retracting. The outer circumference of the steel stamp 5 remains flat and unobstructed, reducing friction and jamming with the inner wall of the mounting hole during removal, making the disassembly of the steel stamp 5 smoother. Simultaneously, the limit stop 513 restricts the maximum retraction distance of the fixing block 511, preventing damage to the spring 512 due to excessive compression and also preventing hard collisions between the fixing block 511 and the inner wall of the fixing hole, protecting components such as the fixing block 511 and spring 512, and extending the service life of the structure.

[0041] The various embodiments of this disclosure have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A device for assembling plastic seals, characterized in that, include: The first handle (1) has a clamp head (11) at one end; The second handle (2) has its front end hinged to the front end of the first handle (1); The pressure block (3) is slidably disposed on the pliers head (11), and the pressure block (3) is provided with mounting holes for installing steel tamperes; Linkage mechanism (4), connected between the second handle (2) and the pressure block (3), is used to convert the closing action of the second handle (2) relative to the first handle (1) into the linear movement of the pressure block (3) toward the pliers (11); In addition, a steel stamp (5) is detachably installed in the mounting hole of the pressure block (3), and the steel stamp (5) is provided with an elastic locking member (51) for locking the steel stamp (5) in the mounting hole.

2. The apparatus for assembling plastic seals according to claim 1, characterized in that, The linkage mechanism (4) includes: Connecting rods (41) are provided on both sides of the pressure block (3); In addition, pressure rods (21) are provided on both sides of the front end of the second handle (2), and the pressure rods (21) are provided with elongated holes, through which the connecting rod (41) passes.

3. The apparatus for assembling plastic seals according to claim 2, characterized in that, The clamp head (11) is provided with a sliding sleeve (111), the pressure block (3) is slidably disposed in the sliding sleeve (111), and the side wall of the sliding sleeve (111) is provided with a clearance hole for the connecting rod (41) to pass through.

4. The apparatus for assembling plastic seals according to claim 1, characterized in that, The elastic locking component (51) includes: Fixing holes provided on the side of the steel stamp (5); A fixing block (511) is slidably disposed within the fixing hole; In addition, a spring (512) disposed between the fixing block (511) and the steel stamp (5) is used to provide an elastic force to the fixing block (511) to make it partially protrude out of the fixing hole; The pressure block (3) is provided with a button hole, and an operable button (31) is provided in the button hole for pressing the fixing block (511) to retract it and release the locking of the steel stamp (5).

5. The apparatus for assembling plastic seals according to claim 4, characterized in that, The fixing block (511) and the fixing hole are provided with a mutually cooperating protrusion and groove structure to limit the sliding stroke of the fixing block (511).

6. The apparatus for assembling plastic seals according to claim 4, characterized in that, The button (31) and the button hole are provided with a mutually cooperating protrusion and groove structure to limit the sliding stroke of the button (31).

7. The apparatus for assembling plastic seals according to claim 2, characterized in that, The pressure rod (21) is arc-shaped, with its convex surface facing away from the hinge axis of the first handle (1) and the second handle (2).

8. The apparatus for assembling plastic seals according to claim 1, characterized in that, The lower end of the pliers (11) is provided with a positioning hole for positioning the plastic seal.

9. The apparatus for assembling plastic seals according to claim 1, characterized in that, The tail of the steel stamp (5) extends from the upper end of the pressure block (3) in the installed state.

10. The apparatus for assembling plastic seals according to claim 4, characterized in that, The fixing hole is provided with a limiting block (513) to limit the maximum extension position of the fixing block (511) so that the outer end face of the fixing block (511) is flush with the outer peripheral surface of the steel stamp (5) when it is fully extended.

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