utility knife

Abstract

The utility model discloses a kind of art knives, it is related to cutter technical field, including knife shell and the blade being arranged in it, knife shell tail end is connected through elastic member and drive assembly, drive assembly is slidably arranged in the sliding slot of knife shell;Drive assembly includes drive shell, locking block is slidably arranged in drive shell, sliding slot is equipped with several clamping grooves on one side groove wall, locking block is inserted into clamping groove in locking state;Limiting column is arranged in drive shell shell, limiting column is inserted into the limiting hole of blade, and limiting step is arranged on the lower surface of drive shell. Realized safe locking under long time use state and storage state, improve safety factor while simplifying structure. Shorten the blade installation time, realize portable replacement blade.

Description

Technical Field

[0001] This utility model relates to the field of cutting tool technology, and in particular to a utility knife. Background Technology

[0002] Most utility knives only have a simple automatic retractable function, with the blade extension and retraction relying on manual button operation. This poses a significant safety hazard during use; if the user accidentally presses the button, the blade head may suddenly extend, easily causing cuts and unnecessary injury. Furthermore, replacing the blade with existing utility knives is inconvenient. The entire knife case must be disassembled, and the blade must be precisely aligned with the slot and other components, making the replacement process time-consuming, greatly inconvenient for the user, and reducing work efficiency.

[0003] Chinese Patent Publication No. CN104999483A, Publication Date: October 28, 2015, discloses a Chinese patent entitled "A Novel Utility Knife," comprising a shell and a blade housed within the shell. The shell has a blade extension opening, the blade has scoring lines, and an adjustment button is located at the tail of the blade. The blade head can extend or retract from the extension opening and has a tip. The patent also includes a blade cap that fits over the extension opening of the shell. The blade cap has a slot containing two pressure-breaking strips, each with a cutting edge. This utility knife lacks a safety locking mechanism, making it easy to accidentally extend the blade due to accidental button activation, posing a safety hazard. Summary of the Invention

[0004] This utility model provides a utility knife that, by setting a locking block and several slots, achieves safe locking in both long-term use and storage states, simplifying the structure while improving the safety factor.

[0005] A further objective of this invention is to shorten the blade installation time and achieve portable blade replacement by setting a limiting post and a limiting step.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a utility knife, comprising a blade shell and a blade disposed therein, wherein the tail end of the blade shell is connected to a drive assembly via an elastic element, and the drive assembly is slidably disposed within a sliding groove of the blade shell; the drive assembly comprises a drive housing, within which a locking block is slidably disposed, and the sliding groove has several slots on one side wall, wherein the locking block extends into the slots in the locked state; a limiting post is provided within the drive housing, extending into a limiting hole in the blade, and a limiting step is provided on the lower surface of the drive housing.

[0007] Preferably, the upper surface of the drive housing has a mounting groove, and the locking block is disposed within the mounting groove, sliding left and right along the groove. The mounting groove extends through the width of the drive housing. Slider blocks are located on both sides of the tail end of the drive housing, positioned at the bottom of the side of the drive housing. Slide rails are located near the sides of the bottom of the sliding groove, and the sliders are mounted on these rails, sliding along them. The length of the slide rails is less than the length of the sliding groove, and the slide rails do not contact the tail end wall of the sliding groove. Two abutments are located at the bottom of the sliding groove, near the sides. The height of the abutments is less than the depth of the sliding groove, and the distance between the two abutments is greater than the width of the tail end of the drive housing. When installing the blade, the tail end of the drive housing rotates around the abutments, i.e., the slider abuts the abutments and rotates. This slider-rail structure makes the sliding of the drive housing within the sliding groove more stable.

[0008] Preferably, the drive housing is a rectangular housing with an open bottom surface. The bottom of the mounting groove has a second limiting hole, and the bottom end of the locking block has a second limiting post that extends into the second limiting hole. The front end of the upper surface of the drive housing gradually slopes upwards to facilitate the user applying force. An extension block is provided at the front end of the upper surface of the drive housing to facilitate the user applying upward force to change the blade. The second limiting post is cylindrical, and the second limiting hole is a near-groove shape formed by two circles joined together. The second limiting post moves along the width direction of the second limiting hole, i.e., the left-right direction. The cooperation between the second limiting post and the second limiting hole further restricts the displacement of the locking block, improving the stability of the locking block.

[0009] Preferably, the locking block has barbs at the bottom of both its front and rear sides, and mounting holes are provided on both the front and rear sides of the mounting groove bottom, with the barbs extending into the mounting holes. The barbs engage with the groove wall to prevent the locking block from shifting accidentally. The second limiting post does not contact the blade. The width of the barbs is smaller than the width of the locking block. This greatly enhances the stability of the locking block, ensuring that it will not shift accidentally due to external force during use, thus guaranteeing a more reliable locking state for the blade.

[0010] Preferably, the limiting post is positioned in front of the mounting slot inside the drive housing, and the limiting post is engaged within the blade limiting hole. The limiting post drives the blade to move back and forth, making the blade movement more stable and precise. The limiting post effectively guides the back and forth movement of the blade.

[0011] Preferably, the width of the locking block is the same as the width of the drive housing, and the length of the locking block is greater than the groove length of the slot. Alternatively, the length of the locking block may be slightly less than the groove length. The number of slots can be set according to specific needs. When long-term use is required, the locking block is engaged when the blade is extended by pushing it left or right into the front slot, eliminating the need to repeatedly push the blade out. When not in use, the locking block is engaged by pushing it left or right into the rear slot to prevent accidental extension of the blade housing. The dimensional matching design of the locking block and the slot ensures that the locking block is more securely engaged within the slot, enhancing locking reliability.

[0012] Preferably, a first mounting hook is provided at the bottom of the sliding groove, and a second mounting hook is provided inside the drive housing. The two ends of the elastic element are respectively fixed in the first and second mounting hooks. This gives the utility knife a safe spring-loaded structure. During use, because the blade is pulled by the elastic element, a continuous forward force is required to overcome the pulling force of the elastic element and pull it out of the knife case. When released, after the locking block returns to the mounting groove, the elastic element can use its own elasticity to pull the blade back into the knife case. After the locking block is pushed into the last slot, the blade will no longer move, preventing accidental contact that could expose the blade and cause injury to the user.

[0013] Preferably, the limiting step is located behind the mounting groove. In the installed state, the tail end of the blade abuts against the limiting step, and the limiting step is inclined. This prevents the blade from being inserted too far during installation. When replacing the blade, insert the blade into the drive housing and push it until it contacts the limiting step. This clarifies the installation position of the blade. When the tail end of the blade contacts the limiting step, it indicates that it is in place. At this time, the limiting block of the blade is aligned with the limiting post, and pressing down completes the installation of the blade.

[0014] Preferably, the upper surfaces of the drive housing and locking block are provided with several protrusions. The sliding groove sidewall has a limiting groove at its front end, and the blade is positioned within the limiting groove, moving along its length. This design increases the friction between the drive housing and the locking block, allowing the user to grip the utility knife more stably during operation. The limiting groove further restricts the blade's movement direction, ensuring it can only move along the length of the limiting groove, preventing deviation or wobbling during movement. The upper surface of the blade housing has third limiting holes on both sides of the sliding groove, and the lower surface of the drive housing has limiting seats on both sides, the limiting seats being stepped.

[0015] Preferably, the blade casing has hollow elastic strips on both sides of the tail end and several raised strips on both sides of the head end. The elastic strips can cushion the force applied by the user and reduce hand fatigue, while the raised strips can increase the friction of the blade casing and prevent it from slipping during use.

[0016] Beneficial effects: By setting a locking block and several slots, the utility knife of this utility model can securely lock the blade when not in use, effectively avoiding safety accidents caused by accidental extension of the blade due to accidental button press, and greatly improving safety during use.

[0017] During use, users can flexibly choose the operating mode according to their actual needs. If only a short-term use is required, the user can release their hand to allow the blade to automatically spring back and retract; if a long-term work is required, the extended blade can be locked, eliminating the need to repeatedly extend the blade, which greatly improves the convenience of operation and work efficiency.

[0018] This invention simplifies the blade installation process and shortens the installation time by setting a limiting post, enabling portable blade replacement. Users can quickly replace blades without precisely aligning them with the slot, greatly improving blade replacement efficiency and user convenience. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of this utility model.

[0020] Figure 2 This is a longitudinal sectional view of the present invention.

[0021] Figure 3 This is a cross-sectional view of the present invention.

[0022] Figure 4 This is a schematic diagram of the structure of the blade shell of this utility model.

[0023] Figure 5 This is a schematic diagram of the structure of this utility model without the blade shell.

[0024] Figure 6 This is a schematic diagram of the locking block of this utility model.

[0025] Figure 7 This is a schematic diagram of the structure of the drive housing and blade of this utility model.

[0026] Reference numerals: 1: Blade housing; 1.1: Protruding strip; 1.2: Elastic strip; 1.3: Sliding groove; 1.3.1: Slide rail; 1.3.2: Abutment; 1.3.3: First mounting hook; 1.3.4: Limiting groove; 1.4: Slot; 1.5: Third limiting hole; 2: Blade; 2.1: Limiting hole; 3: Drive assembly; 3.1: Drive housing; 3.1.1: Limiting post; 3.1.2: Mounting groove; 3.1.3: Second limiting hole; 3.1.4: Mounting hole; 3.1.5: Second mounting hook; 3.1.6: Slider; 3.1.7: Limiting step; 3.1.8: Limiting seat; 3.2: Locking block; 3.2.1: Barb; 3.2.2: Second limiting post; 4: Elastic element. Detailed Implementation

[0027] exist Figure 1 and Figure 2In the illustrated embodiment, the utility knife of this invention uses a blade shell 1 as the basic carrier, internally integrating a blade 2, a drive assembly 3, and an elastic element 4. Through the coordinated operation of these components, the blade 2 can be extended, locked, and easily replaced. The blade shell 1 has a sliding groove 1.3 extending along its length. The drive assembly 3 is slidably installed within the sliding groove 1.3. One end of the drive assembly 3 is connected to the tail end of the blade shell 1 via the elastic element 4, and the other end engages with the limiting hole 2.1 of the blade 2 via a limiting post 3.1.1, enabling the blade 2 to move synchronously back and forth. The core of the drive assembly 3 is the drive housing 3.1. A locking block 3.2 slidably disposed within the drive housing 3.1 engages with several slots 1.4 on the side wall of the sliding groove 1.3, locking the blade 2 when it extends or retracts, preventing accidental movement of the blade 2. Simultaneously, the limiting post 3.1.1 significantly shortens the blade 2 installation time, enabling portable blade replacement and solving the problems of complex structure and cumbersome blade replacement in traditional utility knives.

[0028] exist Figure 3 and Figure 5 In the preferred embodiment shown, the slider 3.1.6 and slide rail 1.3.1 structure of the drive housing 3.1 and the sliding groove 1.3 ensure the stable sliding of the drive assembly 3. The upper surface of the drive housing 3.1 is provided with a through-width mounting groove 3.1.2, and the locking block 3.2 can slide left and right along the mounting groove 3.1.2 to ensure that the moving path of the locking block 3.2 is regular and to avoid locking failure caused by deviation. The bottom of both sides of the tail end of the drive housing 3.1 is provided with sliders 3.1.6, and corresponding to the bottom surface of the sliding groove 1.3 near both sides, there is a slide rail 1.3.1. The sliders 3.1.6 are set on the slide rail 1.3.1 and can slide along the slide rail 1.3.1. This guiding structure makes the sliding of the drive housing 3.1 smoother. The length of the slide rail 1.3.1 is less than the length of the sliding groove 1.3 and does not contact the tail end wall of the sliding groove 1.3, leaving room for rotation of the drive housing 3.1 during replacement; two abutments 1.3.2 are provided at the bottom of the sliding groove 1.3. The slide block 3.1 is positioned near the sides of the bottom of the groove, with its height less than the depth of the sliding groove 1.3 and its spacing greater than the width of the tail end of the drive housing 3.1. When the blade 2 needs to be replaced, the elastic element 4 pulls the tail end of the drive housing 3.1 back to the abutment 1.3.2, causing the slider 3.1.6 to abut against the abutment 1.3.2 and rotate around the abutment 1.3.2. The front end of the drive housing 3.1 is then lifted, exposing the blade 2 installation area without disassembling the entire blade housing 1. This greatly simplifies the blade replacement process, avoids the cumbersome operation of traditional utility knives that require disassembling the outer shell to replace the blade, and improves the efficiency of blade replacement.

[0029] exist Figure 2 and Figure 5In the preferred embodiment shown, the rectangular structure and extension block design of the drive housing 3.1 further optimizes operational convenience and structural stability. The drive housing 3.1 is a rectangular shell with an open bottom and a regular internal space, facilitating the integration of components such as the mounting groove 3.1.2 and the limiting post 3.1.1. The bottom of the mounting groove 3.1.2 is provided with a second limiting hole 3.1.3. The second limiting post 3.2.2 at the bottom of the locking block 3.2 extends into the second limiting hole 3.1.3. The second limiting post 3.2.2 is cylindrical, and the second limiting hole 3.1.3 is a near-groove shape formed by two circles joined together. This matching method allows the locking block 3.2 to move in the left and right direction (i.e., the second limiting post 3.2.2 slides along the width direction of the second limiting hole 3.1.3) while restricting the front and rear displacement of the locking block 3.2, preventing the locking block 3.2 from falling out of the mounting groove 3.1.2, and further improving the stability of the locking block 3.2. The front end of the upper surface of the drive housing 3.1 gradually tilts upward, conforming to ergonomic design. When the user pushes the drive housing 3.1, the force applied by the fingers is more natural, reducing fatigue during long-term operation. The extension block set at the front end provides a convenient force point for tool changing. The front end of the drive housing 3.1 can be easily lifted by pulling the extension block upward, without the need for tools. It is especially suitable for one-handed operation, further reducing the difficulty of tool changing.

[0030] exist Figure 2 and Figure 6 In the preferred embodiment shown, the barb 3.2.1 of the locking block 3.2 cooperates with the mounting hole 3.1.4 to form a reliable anti-accidental contact mechanism. The bottom ends of the front and rear sides of the locking block 3.2 are provided with barbs 3.2.1, corresponding to the front and rear sides of the mounting groove 3.1.2. The barbs 3.2.1 extend into the mounting holes 3.1.4 and engage with the groove wall of the mounting groove 3.1.2. When no external force is applied to push the locking block 3.2, the barbs 3.2.1 can be firmly engaged in the mounting holes 3.1.4, preventing the locking block 3.2 from shifting due to accidental collisions, vibrations, or accidental contact, and avoiding accidental extension or retraction of the blade 2 in a non-operating state, greatly improving safety. The width of the barbs 3.2.1 is smaller than the width of the locking block 3.2, ensuring engagement strength without affecting the left and right sliding of the locking block 3.2. The user only needs to apply a certain pushing force to push the locking block 3.2, balancing safety and ease of operation. Meanwhile, the second limiting post 3.2.2 does not contact the blade 2, thus avoiding friction between the limiting post and the blade 2 during the extension and retraction of the blade 2, reducing wear on the blade 2, extending the service life of the blade 2, and preventing operational jamming caused by friction, ensuring smooth extension and retraction of the blade 2.

[0031] exist Figure 2In the preferred embodiment shown, the cooperation between the limiting post 3.1.1 and the limiting hole 2.1 of the blade 2 enables stable driving and precise positioning of the blade 2. The limiting post 3.1.1 is located in front of the mounting groove 3.1.2 inside the drive housing 3.1, and its position precisely corresponds to the limiting hole 2.1 of the blade 2. When installing the blade 2, simply align the limiting hole 2.1 of the blade 2 with the limiting post 3.1.1 and insert it to complete the connection between the blade 2 and the drive assembly 3. There is no need to repeatedly adjust the position, achieving "one-plug installation" and significantly shortening the tool change time. In use, the drive housing 3.1 slides back and forth, causing the limiting post 3.1.1 to move synchronously. The limiting post 3.1.1 then drives the blade 2 to extend and retract along the sliding groove 1.3. This rigid connection ensures that there is no relative sliding between the blade 2 and the drive housing 3.1, and the extension and retraction length of the blade 2 is consistent with the movement distance of the drive housing 3.1, improving operating accuracy. Traditional utility knives often experience blade 2 misalignment or jamming during extension and retraction due to loose connection between the blade 2 and the drive assembly 3. However, the blade 2 of this invention always extends and retracts smoothly along a preset trajectory, ensuring the accuracy of the cutting operation.

[0032] In actual operation and tool changing, the synergistic effect of each component is particularly significant: During use, pushing the drive housing 3.1 overcomes the pulling force of the elastic element 4, causing the blade 2 to extend. When the blade 2 extends to the required length, pushing the locking block 3.2 to one side allows it to enter the corresponding slot 1.4 on the side wall of the sliding groove 1.3, achieving locking without continuous force. When not in use, pushing the locking block 3.2 disengages it from the slot 1.4, and the elastic element 4 uses its own elasticity to pull the drive housing 3.1 and blade 2 back into the tool housing 1. Then, pushing the locking block 3.2 into the tail end slot 1.4 locks it in place, preventing accidental activation. When changing the blade 2, lifting the drive housing 3.1 causes it to rotate around the abutment 1.3.2, raising the front end. After removing the old blade 2, aligning the limiting hole 2.1 of the new blade 2 with the limiting post 3.1.1 and inserting it, then lowering the drive housing 3.1 completes the installation. The entire process requires no tools and is very convenient.

[0033] exist Figure 1 and Figure 5In the preferred embodiment shown, the size-matched design of the locking block 3.2 and the slot 1.4 is the core of achieving reliable locking of the blade 2. The width of the locking block 3.2 is exactly the same as the width of the drive housing 3.1. This design ensures that when the locking block 3.2 slides in the mounting groove 3.1.2 of the drive housing 3.1, the force is even and there is no one-sided offset. This avoids jamming or tilting of the locking block 3.2 due to width mismatch, thus extending the service life of the locking structure. The length of the locking block 3.2 is slightly less than the groove length of the slot 1.4. When the locking block 3.2 extends into the slot 1.4, even if it is subjected to a slight external impact, the locking block 3.2 is not easy to fall out of the slot 1.4, ensuring that the blade 2 is fixed in position in the locked state and will not extend or retract unexpectedly. The number of slots 1.4 can be flexibly set according to actual usage needs. For example, multiple slots 1.4 can be evenly distributed on the side wall of the sliding groove 1.3, which can not only meet the locking requirements of different extension lengths of the blade 2, but also adapt to short-term and long-term use scenarios: When long-term continuous cutting operations are required, after the blade 2 is pushed out to the appropriate length, the locking block 3.2 is pushed to one side to lock it into the corresponding slot 1.4, which can lock the extension state of the blade 2 without the user having to continuously apply pushing force, reducing hand burden and avoiding the tedious operation caused by repeatedly pushing out the blade 2; when the utility knife is not in use, after the blade 2 is completely retracted into the blade shell 1, the locking block 3.2 is pushed into the slot 1.4 at the tail end, which can completely fix the position of the blade 2 and prevent the blade 2 from accidentally extending due to accidental contact with the drive component 3, eliminating safety hazards when carrying or storing. This "multi-position locking" design takes into account the needs of different usage scenarios, greatly improving the applicability of the utility knife.

[0034] exist Figure 5In the preferred embodiment shown, the elastic element 4 mounting structure between the sliding groove 1.3 and the drive housing 3.1 provides the utility knife with a safe spring-back function, further enhancing safety during use. A first mounting hook 1.3.3 is provided at the bottom of the sliding groove 1.3, and a second mounting hook 3.1.5 is provided at a corresponding position inside the drive housing 3.1. The two ends of the elastic element 4 are respectively fixed within the two mounting hooks, forming an elastic connection of "drive assembly 3 - elastic element 4 - blade housing 1". During use, since the elastic element 4 is always in a stretched state, it will exert a backward pulling force on the drive housing 3.1. The user needs to apply a forward pushing force to overcome this pulling force in order to push the blade 2 out of the blade housing 1. If the pushing force is released and the locking block 3.2 is not engaged in the slot 1.4, the elastic element 4 will immediately use its own elasticity to pull the drive housing 3.1 backward, causing the blade 2 to automatically retract into the blade housing 1, achieving a "retract immediately upon release" safety effect and avoiding accidental cuts caused by forgetting to retract the blade 2. Once blade 2 is fully retracted, push the locking block 3.2 into the tail end slot 1.4. Blade 2 will remain fixed in place, completely eliminating the risk of accidental exposure. Compared to traditional utility knives without a spring-loaded mechanism, this design eliminates the need to manually push blade 2 back, making operation more convenient and minimizing safety hazards caused by human error. It is especially suitable for household scenarios where children may come into contact with the blade or for high-frequency industrial scenarios.

[0035] exist Figure 2 In the preferred embodiment shown, the limiting step 3.1.7 is located behind the mounting groove 3.1.2. In the installed state, the tail end of the blade 2 abuts against the limiting step 3.1.7, which is tilted. This prevents the blade 2 from being inserted too far during installation, avoiding collisions between the blade 2 and internal components of the drive housing 3.1 due to excessive insertion, protecting the structural integrity of both the blade 2 and the drive housing 3.1, and reducing the risk of component damage. When replacing the blade 2, there is no need to repeatedly confirm its position with tools or the naked eye. Simply insert the blade 2 into the drive housing 3.1 and push it until it contacts the limiting step 3.1.7 to confirm that the blade 2 is installed correctly, greatly simplifying the judgment process and reducing operational difficulty. When the tail end of the blade 2 contacts the limiting step 3.1.7, the limiting hole of the blade 2 aligns with the limiting post. Pressing down at this point completes the installation without additional adjustment of the blade 2's angle or position, shortening blade replacement time and improving efficiency. This is especially suitable for single-handed operation or high-frequency blade replacement scenarios, further enhancing the convenience and practicality of the utility knife. The tilt angle of the limiting step 3.1.7 is approximately the same as the tilt angle of the tail end of the blade 2 to prevent the limiting step 3.1.7 from damaging the blade 2.

[0036] The upper surface of the blade housing 1 has third limiting holes 1.5 on both sides of the sliding groove, and the lower surface of the drive housing 3.1 has limiting seats 3.1.8 on both sides. The limiting seats 3.1.8 are stepped. The third limiting hole 1.5 is semi-circular, and the limiting seat 3.1.8 is a semi-cylindrical shape divided along the axis. The higher part of the limiting seat 3.1.8 is located at the bottom. The diameter of the lower half of the limiting seat 3.1.8 is larger than the diameter of the upper half of the limiting seat 3.1.8, and the diameter of the upper half of the limiting seat 3.1.8 is smaller than the diameter of the third limiting hole 1.5. Since the force of the elastic element (preferably a spring) is naturally pulled backward, when the blade 2 needs to be replaced and the drive housing 3.1 is lifted, the stepped limiting seat 3.1.8 naturally gets stuck in the third limiting hole 1.5, eliminating the need to hold it by hand for a long time. This improves the ease of operation. The precise engagement of the limiting seat 3.1.8 and the third limiting hole 1.5 secures the drive housing 3.1 in its raised position, preventing accidental drop of the drive housing 3.1 during blade changing, which could result in hand injury or misalignment of the blade 2, thus further ensuring the safety of the blade changing operation. This engagement structure requires no additional locking components; stable positioning is achieved solely through the tension of the existing elastic elements. This simplifies the overall structural design, reduces the probability of component wear, extends the lifespan of the utility knife, and balances convenience, safety, and durability.

[0037] exist Figure 4 In the preferred embodiment shown, the raised design on the upper surfaces of the drive housing 3.1 and the locking block 3.2, as well as the limiting groove 1.3.4 at the front end of the sliding groove 1.3, optimizes the user experience in terms of both operational stability and cutting accuracy. The raised surfaces of the drive housing 3.1 and the locking block 3.2 increase the friction between the hand and the components: when the user pushes the drive housing 3.1 or the sliding locking block 3.2, the raised surfaces prevent fingers from slipping, especially when hands are wet, sweaty, or wearing gloves, ensuring stable force application and avoiding operational deviations or hand fatigue caused by slippage. The limiting groove 1.3.4 at the front end of the sliding groove 1.3 sidewall extends along the length of the blade housing 1 in a long strip shape. One side of the blade 2 extends into the limiting groove 1.3.4 and can only move along the length of the limiting groove 1.3.4. This design completely restricts the vertical displacement of the blade 2, preventing the blade 2 from skewing or wobbling during extension, retraction, or cutting, ensuring a straight cutting trajectory and improving cutting accuracy. Meanwhile, the limiting groove 1.3.4 can also protect the edge of the blade 2, avoid blade wear caused by direct friction between the blade 2 and the side wall of the sliding groove 1.3 during movement, extend the sharpness retention time of the blade 2, and reduce the frequency of consumable replacement.

[0038] exist Figure 1In the preferred embodiment shown, the hollow elastic strip 1.2 at the tail of the blade shell 1 and the raised strip 1.1 at the head enhance the user experience in terms of both grip comfort and anti-slip performance. The hollow elastic strip 1.2 on both sides of the tail of the blade shell 1 is made of flexible material and has good deformation capability: when the user holds the tail of the blade shell 1, the elastic strip 1.2 can deform slightly according to the contour of the hand, conforming to the curve of the palm, reducing the pressure of the hard shell on the palm, and maintaining a comfortable grip even after long-term use, effectively relieving hand fatigue. Several raised strips 1.1 on both sides of the head of the blade shell 1 are evenly distributed. Their raised structure can increase the friction between the hand and the blade shell 1. Especially when the cutting force is large or the hands are sweaty, the raised strips 1.1 can prevent the blade shell 1 from slipping out of the hand, ensuring the stability and safety of the cutting operation. In addition, the hollow elastic strip 1.2 can reduce the overall weight of the knife shell 1 and improve portability, while the design of the raised strip 1.1 also enriches the appearance of the knife shell 1, making the utility knife more recognizable, and taking into account both practicality and aesthetics.

[0039] In practical applications, the synergistic effect of each component is particularly evident: users need to frequently switch between cutting and pause states. In such cases, the springback function of the elastic element 4 can be utilized—for short cuts, the blade 2 can be extended and automatically retracted upon releasing the hand, eliminating the need for repeated operation of the locking block 3.2; for longer paper cutting, the blade 2 can be extended to a suitable length, and the locking block 3.2 can be pushed into the front slot 1.4. Once locked, no continuous force is required, reducing hand strain. When the blade 2 becomes dull and needs replacement, simply pull up the extension block at the front of the drive housing 3.1, causing the tail end of the drive housing 3.1 to rotate around the abutment 1.3.2. After the front end lifts, remove the old blade 2, align the limiting hole 2.1 of the new blade 2 with the limiting post 3.1.1, insert it, and then lower the drive housing 3.1 to complete the installation. The entire process requires no tools and can be operated with one hand. In industrial packaging scenarios, workers need to wear gloves to operate. The protrusions on the drive housing 3.1 and the protrusions 1.1 on the head of the blade housing 1 ensure a stable grip, while the limiting grooves 1.3.4 ensure that the trajectory is straight when cutting the carton, greatly improving work efficiency.

Claims

1. A utility knife, characterized in that, It includes a blade housing and a blade disposed therein. The tail end of the blade housing is connected to a drive assembly via an elastic element. The drive assembly is slidably disposed within a sliding groove of the blade housing. The drive assembly includes a drive housing, a locking block is slidably provided inside the drive housing, and a sliding groove has several slots on one side of the groove wall. In the locked state, the locking block extends into the slots. The drive housing is equipped with a limiting post that extends into the limiting hole of the blade, and the lower surface of the drive housing is equipped with a limiting step.

2. The utility knife according to claim 1, characterized in that, The upper surface of the drive housing is provided with a mounting groove, and the locking block is set in the mounting groove and slides left and right along the mounting groove.

3. The utility knife according to claim 2, characterized in that, The drive housing is a rectangular housing with an open bottom. The bottom of the mounting groove is provided with a second limiting hole, and the bottom end of the locking block is provided with a second limiting post, which extends into the second limiting hole.

4. The utility knife according to claim 1 or 3, characterized in that, The locking block has barbs at the bottom of its front and rear sides, and mounting holes are provided on the front and rear sides of the mounting groove, with the barbs extending into the mounting holes.

5. The utility knife according to claim 3, characterized in that, The limiting post is located in front of the mounting slot inside the drive housing, and the limiting post is locked in the blade limiting hole.

6. The utility knife according to claim 1 or 2, characterized in that, The width of the locking block is the same as the width of the drive housing, and the length of the locking block is less than the length of the slot.

7. The utility knife according to claim 1, characterized in that, The bottom of the sliding groove is provided with a first mounting hook, and the drive housing is provided with a second mounting hook. The two ends of the elastic element are respectively fixed in the first mounting hook and the second mounting hook.

8. The utility knife according to claim 2, characterized in that, The limiting step is located behind the mounting groove. In the installed state, the tail end of the blade abuts against the limiting step, and the limiting step is inclined.

9. The utility knife according to claim 2, characterized in that, The upper surface of the blade housing has a third limiting hole on both sides of the sliding groove, and the lower surface of the drive housing has a limiting seat on both sides, the limiting seat being stepped.

10. The utility knife according to claim 1, characterized in that, Hollow elastic strips are provided on both sides of the tail of the blade, and several protruding strips are provided on both sides of the head of the blade.

Images