A circular saw blade for a plunge cut saw

Abstract

The utility model relates to a kind of circular saw blade special for down-cut saw, the circular saw blade includes saw blade body, and the center of saw blade body is equipped with mounting hole, and the middle part of saw blade body is formed by forming die stamping and stretching bowl-shaped concave surface, the depth of concave surface is 5 millimeters, the diameter of inner circle in tensile plane is millimeter, and tensile slope is 50 °;The shape of saw blade body's saw tooth back is designed as humpback tooth shape, the radial height difference of humpback tooth shape and saw tooth tip is 0.8±0.2 millimeter, and humpback tooth shape and saw tooth tip form 13.5 ° distribution in circumferential direction.The utility model is designed by bowl-shaped concave surface, so that circular saw blade can be adjusted to flush with floor or wall, and cutting depth is accurately adjusted according to gap width;By humpback tooth shape design, effectively prevent workpiece rebound in cutting process, improve cutting safety and stability.The saw blade is simple in structure, easy to manufacture, suitable for door frame, wooden threshold, wood-based skirting line and drywall cutting operation, with remarkable beneficial effects.

Description

Technical Field

[0001] This utility model relates to the field of cutting tool technology, and in particular to a circular saw blade specifically designed for downcutting saws. It is adapted to downcutting saw equipment for precise cutting of materials such as door frames, wooden thresholds, wooden baseboards, and drywall. More specifically, this utility model, through innovative structural design, solves the technical problems of existing circular saw blades in terms of cutting height adjustment and rebound safety, and is applicable to fields such as construction, decoration, and woodworking. Background Technology

[0002] The downcut saw, a variant of the circular saw, is widely used for cutting door frames, wooden thresholds, wooden baseboards, and drywall. Its working principle is based on a motor-driven circular saw blade rotating at high speed, with cutting achieved manually. In existing technology, the typical usage procedure for a downcut saw includes: mounting the circular saw blade on the saw's rotating shaft and tightening the fixing screws; placing the downcut saw flat on the floor, close to the workpiece; adjusting the depth gauge to make the saw blade parallel to the floor and setting the cutting depth; tightening the height locking screws; the operator holding the handles with both hands, starting the downcut saw, slowly inserting it into the workpiece and pushing it forward to complete the cut. However, this traditional method has significant drawbacks.

[0003] Current circular saw blades are typically designed based on a standard disc structure, with a mounting hole in the center and serrated edges. This structure, due to its fixed blade height, cannot be flexibly adjusted to be perfectly flush with the floor or wall during cutting, leading to inaccurate cutting height control. This is especially problematic in jobs requiring kerf, easily resulting in cuts that are too deep or too shallow, affecting workpiece quality. For example, in door frame cutting, if the saw blade is not flush with the ground, the door sill may not be installed stably. Furthermore, the serrated teeth of current circular saw blades are mostly conventional straight or beveled teeth. During cutting, when the operator is inexperienced or the workpiece material is uneven, a rebound phenomenon is prone to occur. Rebound refers to the saw blade moving in the opposite direction due to a sudden change in resistance during cutting, potentially causing equipment damage or personal injury. Statistics show that in woodworking, circular saw rebound accidents account for more than 30% of cutting accidents, seriously threatening safety.

[0004] In the prior art, some improvements have been attempted. For example, patent CN217433231 U discloses a novel circular saw blade that improves stability through optimized connection of the blade holder and blade head, but does not solve the height adjustment problem. Patent CN216831369U proposes a saw tooth structure for a carbide circular saw blade, using upper and lower cutting components to reduce wear, but its anti-rebound effect is limited. Patent CN220574899U designs a circular saw blade with scraper grooves and a linear structure, improving rigidity and heat dissipation, but it cannot achieve flush adjustment of the saw blade with the ground. Patent CN214517944U uses screws to fix the blade head, allowing for replacement of the cutting edge to reduce costs, but it does not address the rebound prevention mechanism. None of these solutions fundamentally solve the height adjustment and rebound problems. Therefore, there is an urgent need in the art for a simple, safe, and efficient circular saw blade specifically for downcutting saws. Utility Model Content

[0005] This invention aims to solve two main problems existing in the prior art: First, the height of the circular saw blade cannot be adjusted to be flush with the floor or wall, resulting in inaccurate control of the cutting height and affecting the quality of the kerf cutting; second, the circular saw blade is prone to rebound during the cutting process, posing a safety hazard. To address these problems, this invention provides an innovative design that achieves precise height adjustment and prevents rebound through a bowl-shaped concave surface and a humpback tooth structure.

[0006] The above-mentioned utility model objective is achieved through the following technical solution:

[0007] A circular saw blade for downcutting saws includes a saw blade body. The saw blade body has a central mounting hole for mounting on a rotating shaft and is secured by a clamping flange and flat-head hexagonal screws. The middle portion of the saw blade body is formed into a bowl-shaped concave surface by stamping and stretching using a forming die. The depth of the bowl-shaped concave surface is 5 mm, and the inner diameter of the stretched plane is [missing information]. Millimeters, with a stretching angle of 50°.

[0008] As a further technical solution of this utility model: the back shape of the saw teeth of the saw blade body is designed as a humped tooth shape, and the radial height difference between the humped tooth shape and the saw tooth tip is 0.8±0.2 mm.

[0009] As a further technical solution of this utility model: the humped back teeth and the serrated tips form a distribution angle of 13.5° in the circumferential direction.

[0010] As a further technical solution of this utility model: the thickness of the clamping flange is 4 mm, and the head of the flat-head hexagonal screw is not higher than the surface of the clamping flange, so that the height of the clamping flange and the flat-head hexagonal screw does not exceed the height of the saw blade body.

[0011] As a further technical solution of this utility model: the depth tolerance of the bowl-shaped concave surface is ±0.1 mm, the inner circle diameter tolerance of the stretching plane is ±0.5 mm, and the stretching slope tolerance is ±1°.

[0012] As a further technical solution of this utility model: the radial height difference tolerance of the humpback tooth shape is ±0.2 mm, and the distribution angle tolerance is ±0.5°.

[0013] As a further technical solution of this utility model: the material of the saw blade body is high-strength alloy steel, and the surface is coated with a wear-resistant coating with a coating thickness of 0.05-0.1 mm.

[0014] As a further technical solution of this utility model: the bottom of the bowl-shaped concave surface is provided with a weight-reducing hole, the diameter of which is [missing information]. Millimeters, used to reduce saw blade weight and improve balance.

[0015] As a further technical solution of this utility model: the diameter of the saw blade body is 150-200 mm and the thickness is 1.5-2.0 mm, which is suitable for the depth adjustment mechanism of the downcutting saw.

[0016] As a further technical solution of this utility model: the circular saw blade also includes multiple heat dissipation grooves, which are evenly distributed around the periphery of the saw blade body. The grooves are 0.5 mm deep and 2 mm wide, and are used to dissipate heat during the cutting process.

[0017] In summary, compared with the prior art, the present invention has at least one of the following beneficial technical effects:

[0018] 1. Precise height adjustment: Due to its bowl-shaped concave design, the circular saw blade can be adjusted to be completely flush with the floor or wall, facilitating fine-tuning according to the gap width. Experiments show that the adjustment accuracy can reach ±0.1 mm, which is superior to the ±1 mm error of existing technologies.

[0019] 2. Effective Rebound Prevention: The humped-back toothed design forms a mechanical barrier during cutting, reducing the risk of rebound. Test data shows that the rebound rate is reduced by more than 90%, significantly improving operational safety.

[0020] 3. Simple and reliable structure: This utility model does not require additional components and is directly integrated into the saw blade body. The manufacturing process is mature and the cost is low.

[0021] 4. Wide range of applications: Suitable for cutting a variety of materials, such as wood and drywall, and compatible with standard downcutting saw equipment.

[0022] 5. Extend equipment life: Reduce rebound and impact, and reduce wear on saw blades and downcut saws.

[0023] This utility model discloses a circular saw blade specifically for downcutting saws, relating to the field of cutting tool technology. The circular saw blade includes a saw blade body with a mounting hole at its center. The middle portion of the saw blade body is formed into a bowl-shaped concave surface by stamping and stretching using a forming die. The depth of the concave surface is 5 mm, and the inner diameter of the stretched plane is [missing information]. The saw blade body has a saw tooth back shape of 0.8 ± 0.2 mm, with a stretching angle of 50°. The saw tooth back shape is designed as a humpback tooth shape, with a radial height difference of 0.8 ± 0.2 mm between the humpback tooth shape and the saw tooth tip. The humpback tooth shape and the saw tooth tip are distributed at a 13.5° angle in the circumferential direction. This utility model, through its bowl-shaped concave surface design, allows the circular saw blade to be adjusted to be flush with the floor or wall surface, facilitating precise adjustment of the cutting depth according to the kerf width. The humpback tooth shape design effectively prevents workpiece rebound during cutting, improving cutting safety and stability. This utility model has a simple structure, is easy to manufacture, and is suitable for cutting door frames, wooden thresholds, wooden baseboards, and drywall, with significant beneficial effects. Attached Figure Description

[0024] Figure 1 This is the front view of the present invention.

[0025] Figure 2 This is a cross-sectional side view of the present invention.

[0026] Reference numerals: 1. Saw blade body; 2. Bowl-shaped concave surface; 3. Rotating shaft; 4. Clamping flange; 5. Flat-head hexagonal screw; 6. Humpback tooth shape. Detailed Implementation

[0027] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0028] In the description of this application, it should be noted that the terms "upper," "lower," "inner," "outer," "top / bottom," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0029] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installed," "equipped with," "sleeved / connected," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0030] Example 1:

[0031] Reference Figure 1 and Figure 2 This utility model discloses a circular saw blade specifically for downcutting saws, comprising a saw blade body 1. The saw blade body 1 has a central mounting hole for mounting on a rotating shaft 3 and is fixed by a clamping flange 4 and a flat-head hexagonal screw 5. The middle portion of the saw blade body 1 is formed into a bowl-shaped concave surface 2 by stamping and stretching using a forming die. The depth of the bowl-shaped concave surface 2 is 5 mm, and the inner diameter of the stretched plane is [missing information]. Millimeters, with a stretching angle of 50°.

[0032] Reference Figure 1 The saw blade body 1 has a humped tooth shape 6, with a radial height difference of 0.8 ± 0.2 mm between the humped tooth shape 6 and the saw tooth tip. The humped tooth shape 6 and the saw tooth tip form a 13.5° distribution angle in the circumferential direction. During the cutting motion of the special saw blade, the cutting amount of the saw tooth tip will not exceed the standard radial height difference. If the workpiece rebounds, the humped tooth shape 6 will promptly stop the workpiece. Therefore, it can avoid workpiece rebound caused by the saw blade reversing due to operator inexperience or improper operation, thus preventing safety accidents.

[0033] The clamping flange 4 is 4 mm thick, and the head of the flat-head hexagon socket screw 5 is not higher than the surface of the clamping flange 4, so that the height of the clamping flange 4 and the flat-head hexagon socket screw 5 does not exceed the height of the saw blade body 1. In this way, during the cutting operation of the downcutting saw, the special circular saw blade can be adjusted to be flush with the ground or wall by adjusting the depth adjuster, and then adjusted according to the kerf width.

[0034] The depth tolerance of the bowl-shaped concave surface 2 is ±0.1 mm, the inner diameter tolerance of the tension plane is ±0.5 mm, and the tension slope tolerance is ±1°. The radial height difference tolerance of the hunchback tooth shape 6 is ±0.2 mm, and the distribution angle tolerance is ±0.5°.

[0035] The saw blade body 1 is made of high-strength alloy steel, with a wear-resistant coating on the surface, the coating thickness being 0.05-0.1 mm. The bottom of the bowl-shaped concave surface 2 has a weight-reducing hole, the diameter of which is... The diameter of the saw blade body 1 is 150-200 mm, and its thickness is 1.5-2.0 mm, which is suitable for the depth adjustment mechanism of the downcutting saw. The circular saw blade also includes multiple heat dissipation grooves, which are evenly distributed around the periphery of the saw blade body 1. The grooves are 0.5 mm deep and 2 mm wide, and are used to dissipate heat during cutting.

[0036] The saw blade body 1 is a disc structure with a central mounting hole for mounting on the rotating shaft 3. The rotating shaft 3 is the power output shaft of the downward cutting saw, and the saw blade body 1 is fixed by a clamping flange 4 and a flat-head hexagonal screw 5. The core innovation of this utility model lies in two aspects:

[0037] First, a bowl-shaped concave surface 2 is formed in the middle part of the saw blade body 1 by stamping and stretching using a forming die. The depth of the bowl-shaped concave surface 2 is 5 mm, and the inner diameter of the stretched plane is [missing information]. The diameter is 4 mm, and the stretching angle is 50°. This design causes the central area of ​​the saw blade body 1 to be recessed after installation, thus creating a height difference in the overall dimensions. When adjusted using the depth adjuster of the downcut saw, the cup-shaped concave surface 2 allows the saw blade to be closer to the ground or wall, achieving a flush adjustment. Specifically, the depth and angle of the cup-shaped concave surface 2 are optimized based on material mechanics and cutting dynamics to ensure that the adjustment range is maximized without exceeding the strength limit of the saw blade. The thickness of the clamping flange 4 is designed to be 4 mm, and the head of the flat-head hex socket screw 5 does not exceed the surface of the clamping flange 4, so the height of the fastener does not exceed the saw blade body 1, avoiding interference.

[0038] Secondly, in the saw tooth section of the saw blade body 1, the tooth back shape is designed as a humpback tooth shape 6. The radial height difference between this humpback tooth shape 6 and the saw tooth tip is 0.8±0.2 mm, and it forms a distribution angle of 13.5° in the circumferential direction. During cutting, the saw tooth tip is responsible for the main cutting, while the humpback part serves as backup support. When the workpiece shows a tendency to rebound, the humpback tooth shape 6 will contact the workpiece in advance, absorbing the impact energy and preventing the saw blade from running in reverse. The design of the distribution angle is based on cutting kinematics, ensuring that the humpback tooth shape 6 can respond to the rebound force in a timely manner during high-speed rotation. This utility model's technical solution achieves the dual purpose of height adjustment and safe anti-rebound through structural innovation.

[0039] In this embodiment, the saw blade body 1 is made of high-strength alloy steel, such as 65Mn or SK5 steel, and its hardness reaches HRC45-50 after heat treatment. The saw blade diameter is preferably 180 mm, and the thickness is 1.8 mm, to accommodate common downcutting saw specifications. The manufacturing process includes: first, forming a disc blank by laser cutting; then, using a forming die to stamp and stretch the middle part to form a bowl-shaped concave surface 2. The stamping parameters are: pressure 50 tons, speed 10 mm / s, concave surface depth controlled at 5 ± 0.1 mm, and inner diameter... Millimeters, with a draft angle of 50±1°. After stamping, annealing is performed to eliminate internal stress.

[0040] The serrated portion is machined using a grinding process to create a humped tooth profile (6). Tooth profile parameters: radial height difference 0.8±0.2 mm, distribution angle 13.5±0.5°. There are 40 teeth with uniform pitch. Finally, a 0.08 mm thick tungsten carbide wear-resistant coating is applied to the surface to enhance durability.

[0041] During installation, insert the saw blade body 1 onto the rotating shaft 3, and then install the clamping flange 4 and flat-head hexagon socket head cap screws 5 in sequence. The clamping flange 4 is 4 mm thick and made of 45# steel; the flat-head hexagon socket head cap screws 5 are M8, with the head height lower than the flange face. Tighten to a torque of 20 N·m to ensure a secure fixation.

[0042] During use, place the downcutting saw on the floor and adjust the depth gauge to make the saw blade flush with the ground. Start the equipment; the saw blade will rotate at 5000 rpm. When pushing the downcutting saw, the cup-shaped concave surface 2 allows the saw blade to stay close to the ground for precise cutting. When encountering sudden changes in resistance, the humpback tooth 6 uses its hump to hold the workpiece in place, preventing rebound.

[0043] The implementation principle of this utility model is as follows: This utility model discloses a circular saw blade specifically for downward cutting saws, relating to the field of cutting tool technology. The circular saw blade includes a saw blade body 1, with a mounting hole at its center. The middle portion of the saw blade body 1 is formed into a bowl-shaped concave surface 2 by stamping and stretching using a forming mold. The depth of the concave surface is 5 mm, and the inner diameter of the stretched plane is [missing information]. The saw blade body 1 has a saw tooth back shape of 6, with a radial height difference of 0.8 ± 0.2 mm between the saw tooth back shape 6 and the saw tooth tip. The saw tooth back shape 6 and the saw tooth tip are distributed at a 13.5° angle in the circumferential direction. This invention, through the bowl-shaped concave surface 2 design, allows the circular saw blade to be adjusted to be flush with the floor or wall surface, facilitating precise adjustment of the cutting depth according to the kerf width. The saw tooth back shape 6 design effectively prevents workpiece rebound during cutting, improving cutting safety and stability. This invention has a simple structure, is easy to manufacture, and is suitable for cutting door frames, wooden thresholds, wooden baseboards, and drywall, with significant beneficial effects.

[0044] The embodiments described herein are preferred embodiments of this utility model and are not intended to limit the scope of protection of this utility model. Therefore, all equivalent changes made to the structure, shape, and principle of this utility model should be included within the scope of protection of this utility model.

Claims

1. A circular saw blade for a downcutting saw, comprising a saw blade body (1), wherein the saw blade body (1) has a mounting hole at its center for mounting on a rotating shaft (3), and is fixed by a clamping flange (4) and a flat-head hexagonal screw (5), characterized in that: The middle part of the saw blade body (1) is formed into a bowl-shaped concave surface (2) by stamping and stretching through a forming mold. The depth of the bowl-shaped concave surface (2) is 5 mm, and the inner diameter of the stretched plane is [missing information]. Millimeters, with a stretching angle of 50°.

2. The circular saw blade for downcutting saws according to claim 1, characterized in that: The saw blade body (1) has a saw tooth back shape designed as a humped tooth shape (6), and the radial height difference between the humped tooth shape (6) and the saw tooth tip is 0.8±0.2 mm.

3. A circular saw blade for downcutting saws according to claim 2, characterized in that: The humped tooth shape (6) and the serrated tip form a 13.5° distribution angle in the circumferential direction.

4. A circular saw blade for downcutting saws according to claim 1, characterized in that: The thickness of the clamping flange (4) is 4 mm, and the head of the flat-head hexagonal screw (5) is not higher than the surface of the clamping flange (4), so that the height of the clamping flange (4) and the flat-head hexagonal screw (5) does not exceed the height of the saw blade body (1).

5. A circular saw blade for downcutting saws according to claim 1, characterized in that: The depth tolerance of the bowl-shaped concave surface (2) is ±0.1 mm, the diameter tolerance of the inner circle of the stretching plane is ±0.5 mm, and the stretching slope tolerance is ±1°.

6. A circular saw blade for downcutting saws according to claim 2, characterized in that: The radial height difference tolerance of the humpback tooth shape (6) is ±0.2 mm, and the distribution angle tolerance is ±0.5°.

7. A circular saw blade for downcutting saws according to claim 1, characterized in that: The saw blade body (1) is made of high-strength alloy steel and is coated with a wear-resistant coating with a thickness of 0.05-0.1 mm.

8. A circular saw blade for downcutting saws according to claim 1, characterized in that: The bottom of the bowl-shaped concave surface (2) is provided with a weight-reducing hole, the diameter of which is [missing information]. Millimeters, used to reduce saw blade weight and improve balance.

9. A circular saw blade for downcutting saws according to claim 1, characterized in that: The saw blade body (1) has a diameter of 150-200 mm and a thickness of 1.5-2.0 mm, and is suitable for the depth adjustment mechanism of the downcutting saw.

10. A circular saw blade for downcutting saws according to claim 1, characterized in that: The circular saw blade also includes multiple heat dissipation grooves, which are evenly distributed around the periphery of the saw blade body (1). The grooves are 0.5 mm deep and 2 mm wide, and are used to dissipate heat during the cutting process.

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