Pipe fitting connecting structure and electric circular saw

Abstract

The invention discloses a pipe fitting connecting structure and an electric circular saw, the pipe fitting connecting structure comprises a pipe orifice and a pipe fitting inserted in the pipe orifice, and the pipe fitting and the pipe orifice are fixedly and rotatably connected in the axial direction and the circumferential direction of the pipe fitting respectively; a positioning assembly is arranged between the pipe fitting and the pipe orifice; the positioning assembly is suitable for limiting the pipe fitting to a plurality of preset positions in the circumferential direction of the pipe fitting. The limiting part which is in limiting connection with the pipe fitting in the axial direction is arranged on the pipe opening, so that connection of the pipe fitting and the pipe opening is achieved, the first positioning part is arranged on the pipe fitting in the circumferential direction, and through elastic deformation of the limiting part, the limiting part abuts against the first positioning part in the radial direction of the pipe fitting when making contact with the first positioning part, and fixing is achieved; therefore, the pipe fitting is fixed at a specific rotating angle, the application scene is wide, when the pipe fitting is applied to a dust discharge pipe structure, the dust discharge requirements at different angles are met, and the use activity space of an electric tool is enlarged.

Description

Technical Field

[0001] The present invention relates to the technical field of electric tools, and in particular to a pipe connection structure and an electric circular saw. Background Art

[0002] Power tools are mechanized tools that use an electric motor or electromagnet as a power source and drive a working head through a transmission mechanism. They are lightweight, easy to carry, highly efficient and low in energy consumption. They are widely used in industrial and household fields. Industrial uses include drilling, tapping, sawing, rust removal and polishing, while household uses include decoration, repair, installation and gardening. For many power tools, such as circular saws for sawing, a dust suction function is added to suck out the powder produced by cutting while sawing. In traditional designs, the dust exhaust pipe is fixedly connected to the housing, and then connected to the dust bag through a hose. In actual use, the dust exhaust pipe limits the use space of the power tool, affecting its use. Summary of the invention

[0003] The purpose of the present invention is to propose a pipe connection structure and an electric circular saw to address the deficiencies of the prior art, so as to realize multi-angle fixed connection of the pipe. When applied to an electric circular saw with a dust exhaust pipe structure, it can meet the dust exhaust requirements at different angles and expand the use space of the power tool.

[0004] The technical solution to achieve the purpose of the present invention is:

[0005] A pipe fitting connection structure comprises a pipe opening and a pipe fitting inserted into the pipe opening, wherein the pipe fitting and the pipe opening are respectively fixedly and rotationally connected along the axial direction and circumferential direction of the pipe fitting; a positioning assembly is arranged between the pipe fitting and the pipe opening; the positioning assembly is suitable for limiting the pipe fitting to a plurality of preset positions along the circumferential direction of the pipe fitting.

[0006] Furthermore, a plurality of first positioning portions are provided on the outer circumferential surface of the pipe fitting, a limiting portion which elastically deforms along the radial direction of the pipe fitting is fixedly provided on the pipe mouth, the first positioning portion and the limiting portion form a positioning assembly, the pipe fitting and the limiting portion are respectively fixedly and rotationally connected along the axial direction and circumferential direction of the pipe fitting, and the limiting portion abuts against the first positioning portion along the radial direction of the pipe fitting.

[0007] Furthermore, the limiting portion is a hollow cylindrical body with an opening along its axial direction, and the hollow cylindrical body is arranged along the tangential direction of the pipe.

[0008] Furthermore, the limiting part is a metal part, which prolongs the service life.

[0009] Furthermore, the hollow columnar body is an elastic cylindrical pin.

[0010] Furthermore, the elastic cylindrical pin is made of 65Mn, and the pipe fitting and the first positioning portion are integrally formed and made of PA6 GF30. The two are used in combination to have better wear resistance and longer service life.

[0011] Furthermore, the limiting parts are symmetrically arranged on both sides of the pipe opening.

[0012] Furthermore, the first positioning portion is a convex portion protruding outward along the radial direction of the pipe, and the convex portion is evenly arranged along the outer circumferential surface of the pipe.

[0013] Furthermore, the side of the protrusion away from the axis of the pipe is a plane.

[0014] Furthermore, the convex parts are symmetrically arranged on the left and right sides of the plane and form an inclined surface with the outer peripheral surface of the pipe.

[0015] Furthermore, the pipe is provided with a plurality of second positioning portions which are located on the same outer peripheral surface as the first positioning portions.

[0016] Furthermore, the second positioning portion is a convex ridge structure arranged along the axial direction of the pipe and having a triangular cross-section. The diameter of the outer circumferential surface formed on the side of the second positioning portion away from the axis of the pipe is D1, the diameter of the outer circumferential surface formed on the side of the first positioning portion away from the axis of the pipe is D2, the outer circumferential surface formed on the side of the limiting portion close to the axis of the pipe has a maximum diameter D3 and an original diameter D4 due to elastic deformation, and the diameter of the outer circumferential surface of the pipe at the first positioning portion is D5, wherein D3>D1>D2>D4>D5.

[0017] Further, D3 ≥ D1 + 0.1 mm, D2 ≥ D4 + 0.1 mm, and D3 ≥ D4 + 0.3 mm.

[0018] Furthermore, eight first positioning parts are evenly arranged along the circumferential direction, and four second positioning parts are arranged and are symmetrically distributed at 30° along the center line L of the pipe. They can serve as a replacement for the failed first positioning part. At the same time, because the highest point of the second positioning part is higher than the convex point of the first positioning part, there will be a sense of obstruction. At this time, more force is required to turn it around, which plays a gear reminder role, prompting the start of entering the rotation angle gear adjustment range.

[0019] Furthermore, an annular groove is provided on the outer circumferential surface of the pipe, the first positioning portion is provided in the annular groove, and the limiting portion is inserted in the annular groove and contacts the bottom surface and both sides of the annular groove.

[0020] Furthermore, the inner ring of the pipe fitting and the first positioning portion are provided with reinforcing ribs located in the same plane to improve the structural strength therein and prevent deformation from affecting the connection stability of the overall structure.

[0021] An electric circular saw comprises a casing, a dust exhaust pipe and the pipe fitting connection structure as described above, wherein the pipe opening is arranged on the casing, and the dust exhaust pipe is fixedly connected to the other end of the pipe fitting.

[0022] By adopting the above technical solution, the present invention has the following beneficial effects:

[0023] (1) The present invention achieves connection between the pipe fitting and the pipe mouth by providing a limiting portion on the pipe mouth that is connected to the pipe fitting along the axial limiting direction, and provides a first positioning portion on the pipe fitting along the circumferential direction. Through the elastic deformation of the limiting portion, the limiting portion and the first positioning portion abut against each other along the radial direction of the pipe fitting when they come into contact, thereby achieving fixation, thereby achieving fixation of the pipe fitting at a specific rotation angle. The present invention has a wide range of application scenarios. When applied to a dust exhaust pipe structure, it can meet the dust exhaust requirements at different angles and expand the use space of the power tool.

[0024] (2) The limiting part of the present invention adopts a hollow columnar body with an opening along the axial direction, so that when subjected to force, the opening is closed and elastically deformed, and the structure is simple.

[0025] (3) The limiting part of the present invention adopts an elastic cylindrical pin, the outer peripheral surface of which is a smooth arc. The contact surface formed along the axial direction of the pipe fitting when in contact with the first positioning part is minimized, thereby reducing the friction surface when the pipe fitting and the pipe mouth rotate relative to each other and reducing wear. At the same time, the elastic force of the elastic cylindrical pin to cause deformation is more stable, easier to reset, and has a long service life.

[0026] (4) The limiting parts of the present invention are symmetrically arranged to ensure that the pipe fitting and the pipe opening are aligned along the axial direction, and the structure is more stable.

[0027] (5) The first positioning portion of the present invention adopts a convex structure, which is convenient for production and processing, saves manufacturing costs, and is evenly distributed along the circumference, which is convenient for adjusting the position of the pipe fitting to meet usage requirements.

[0028] (6) In the present invention, the side of the protrusion close to the limiting portion is a plane, which enlarges the contact surface with the limiting portion and improves the contact stability.

[0029] (7) The two sides of the convex part of the present invention are inclined surfaces, so that when the pipe fitting and the pipe mouth rotate relative to each other, a more natural transition can be achieved, avoiding obvious jerkiness and improving the usability.

[0030] (8) The present invention adds a second positioning portion, so that the second positioning portion can be used as a replacement when the first positioning portion is severely worn after long-term use, thereby improving the service life of the connection structure to a certain extent.

[0031] (9) The second positioning portion of the present invention is preferably a convex rib structure, and the maximum outer diameter is slightly larger than the convex portion, so as to avoid slight permanent deformation of the limiting portion after long-term use, resulting in a slight increase in the minimum inner diameter. By designing the outer diameter of the convex rib structure to be slightly larger than the convex portion, it is ensured that after the convex portion wears out and fails, the convex rib can still maintain contact with the limiting portion to achieve the function of fixing the pipe fitting and the pipe mouth. At the same time, the design of the convex rib structure allows it to maintain minimum contact with the limiting portion when the convex portion is not realized, so as to avoid being mistaken for a convex portion.

[0032] (10) The present invention can realize axial limitation at any angle of rotation through the cooperation between the annular groove and the limiting portion, and has a simple structure and is easy to manufacture. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments and in conjunction with the accompanying drawings, wherein:

[0034] Figure 1 It is a structural schematic diagram of the present invention;

[0035] Figure 2 A top view of the present invention;

[0036] Figure 3 For the present invention Figure 2 Sectional view at AA in the figure;

[0037] Figure 4 It is a schematic diagram of the local structure of the connection part of the present invention;

[0038] Figure 5 It is a structural schematic diagram of the pipe fitting of the present invention;

[0039] Figure 6 It is a schematic diagram of the position structure of the second positioning part.

[0040] The reference numerals in the accompanying drawings are:

[0041] Pipe mouth 1, pipe fitting 2, annular groove 2-1, first positioning portion 3, limiting portion 4, reinforcing rib 5, second positioning portion 6. DETAILED DESCRIPTION

[0042] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0043] (Example 1)

[0044] The electric circular saw of this embodiment includes a housing, a dust exhaust pipe and a pipe connection structure, wherein the pipe connection structure includes a pipe opening 1 and a pipe 2, the pipe opening is arranged on the housing, and the dust exhaust pipe is fixedly connected to the other end of the pipe. Figures 1 to 6As shown, the pipe mouth 1 is fixedly arranged, the pipe fitting 2 is inserted into the pipe mouth 1 and a plurality of first positioning parts 3 are provided on the outer peripheral surface, a limiting part 4 which is elastically deformed along the radial direction of the pipe fitting 2 is fixedly provided on the pipe mouth 1, the pipe fitting 2 and the limiting part 4 are respectively fixedly and rotationally connected along the axial direction and circumferential direction of the pipe fitting 2, the limiting part 4 abuts against the first positioning part 3 along the radial direction of the pipe fitting 2 to achieve fixation, thereby achieving fixation of the pipe fitting 2 at a specific rotation angle, and has a wide range of application scenarios. When applied to the dust exhaust pipe structure, it can meet the dust exhaust requirements at different angles and expand the use space of the power tool.

[0045] Specifically, taking the electric circular saw in the electric tool as an example, the pipe mouth 1 is usually arranged on the protective cover, the outer peripheral surface of the pipe fitting 2 is provided with an annular groove 2-1, and the limiting part 4 is inserted into the annular groove and contacts both sides and the bottom surface of the annular groove, forming the axial rotation and axial fixation of the pipe fitting 2 and the pipe mouth 1 while preventing the pipe fitting from shaking, so that the pipe fitting 1 always keeps in contact with the pipe mouth 1 during the whole process of rotation, with a simple structure, convenient processing, and preventing dust from leaking from the pipe mouth. The limiting part 4 is symmetrically arranged on both sides of the pipe mouth 1, and is inserted into the annular groove 2-1 along the tangent direction of the pipe fitting 2, ensuring that the pipe fitting 2 and the pipe mouth 1 are aligned along the axial direction, and the structure is more stable.

[0046] The limiting part 4 is a hollow cylindrical body of metal structure with a long service life, and is provided with an opening running through the upper and lower parts along its own axial direction, so that when subjected to external force, the size change perpendicular to the axial direction is achieved through the elastic deformation of the metal part and the contraction of the opening. Preferably, the limiting part 4 is an elastic cylindrical pin made of 65Mn, the first positioning part 3 is arranged in the annular groove 2-1, and is integrally formed with the pipe 2, and is made of PA6 GF30. The outer peripheral surface of the elastic cylindrical pin is a smooth arc, and the contact surface formed along the axial direction of the pipe when in contact with the first positioning part 3 is the smallest, which reduces the friction surface when the pipe and the pipe mouth rotate relative to each other, reduces wear, and at the same time, the elastic force of the elastic cylindrical pin to deform is more stable, easier to reset, and has a long service life.

[0047] The first positioning portion 3 is a convex portion protruding outward along the radial direction of the pipe 1. Eight convex portions are evenly arranged along the outer peripheral surface of the pipe 2, which is convenient for production and processing, saves manufacturing costs, and can evenly adjust the position of the pipe 2 to meet the use requirements. The side of the convex portion away from the axis of the pipe 2 is a plane, which expands the contact surface with the limit portion 4 and improves the contact stability. The convex portions are symmetrically arranged on the left and right sides of the plane and form an inclined surface with the outer peripheral surface of the pipe 2, so that when the pipe 2 and the pipe mouth 1 rotate relative to each other, a more natural transition can be achieved, avoiding obvious frustration and improving the use experience.

[0048] Considering that the connection will be subjected to stress for a long time, a reinforcing rib 5 is provided on the same plane as the inner ring of the pipe 2 and the first positioning portion 3 to improve the structural strength of the connection and avoid deformation that affects the connection stability of the overall structure.

[0049] Since the convex part often abuts against the limiting part 4, and the convex part is integrated with the pipe 2, it is generally a plastic part in the field of electric tools, while the limiting part 4 is a metal part. After long-term use, the convex part is easily worn and ineffective. Therefore, a plurality of second positioning parts 6 are also provided on the pipe 2, which are located on the same outer peripheral surface as the first positioning part 3. The second positioning part 6 is a convex ridge structure arranged along the axial direction of the pipe 2, and its cross section is a right triangle. There are 4 second positioning parts in total, which are symmetrically distributed at 30° along the center line L of the pipe. The tip forms a notch with a spacing close to the width of the first positioning part between the tip and the adjacent first positioning part. The diameter of the outer peripheral surface formed on the side away from the axis of the pipe 6 is D1, the diameter of the outer peripheral surface formed on the side away from the axis of the pipe 2 by the first positioning part 3 is D2, the maximum diameter formed by the elastic deformation of the outer peripheral surface formed on the side close to the axis of the pipe 4 is D3, and the original diameter is D4, and the diameter of the outer peripheral surface of the pipe at the first positioning part 3 is D5, and D3>D1>D2>D4>D5. In the actual design, the outer diameter of the rib structure is slightly larger than the convex part, preferably D3=D1+0.1mm, D2=D4+0.1mm, and D3=D4+0.3mm, to avoid slight permanent deformation of the limit part 4 after long-term use, which causes the minimum inner diameter to slightly increase. At the same time, it ensures that after the convex part wears out and fails, the rib can still maintain contact with the limit part to achieve the function of fixing the pipe fitting and the pipe mouth. At the same time, the design of the rib structure is to maintain minimum contact with the limit part when the convex part is not realized, to avoid being mistaken for a convex part.

[0050] In this embodiment, the depth is 2.0mm, the top width of the first positioning part 3 is 3.0mm, the bottom width is 3.4mm, the height is 0.2mm, the two right-angled sides of the second positioning part 6 are 0.3mm and 0.5mm respectively, when the pipe 2 is in the initial state, the 0.5mm long side is set horizontally, D4 = 36.1mm. When the first positioning part is not invalid, in the process of rotating angle fixing, the elastic pin first contacts with the end point of the first positioning part 3, at this time, the deformation of the elastic pin is obvious, reminding the user that it is about to enter the fixed state, pay attention to the applied rotational force, and then the plane of the first positioning part abuts against the elastic pin to achieve fixation; when the second positioning part fails, in the process of rotating angle fixing, the tip of the second positioning part and the end of the adjacent first positioning part abut against the elastic pin at the same time, and fixation is achieved.

[0051] The present invention realizes the connection between the pipe fitting and the pipe mouth by arranging a limiting portion on the pipe mouth, which is connected to the pipe fitting along the axial limiting direction, and arranging a first positioning portion circumferentially on the pipe fitting. Through the elastic deformation of the limiting portion, the limiting portion and the first positioning portion abut against each other along the radial direction of the pipe fitting when they come into contact, so as to realize fixation, thereby realizing fixation of the pipe fitting at a specific rotation angle. The present invention has a wide range of application scenarios. When applied to the dust exhaust pipe structure, it can realize dust exhaust requirements at different angles and expand the use space of the power tool.

[0052] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A pipe connection structure, characterized in that: It comprises a pipe opening and a pipe fitting inserted in the pipe opening, wherein the pipe fitting and the pipe opening are respectively fixedly and rotationally connected along the axial direction and circumferential direction of the pipe fitting; a positioning assembly is arranged between the pipe fitting and the pipe opening; the positioning assembly is suitable for limiting the pipe fitting to a plurality of preset positions along the circumferential direction of the pipe fitting.

2. A pipe connection structure according to claim 1, characterized in that: The outer circumferential surface of the pipe fitting is provided with a plurality of first positioning parts, and a limiting part which elastically deforms along the radial direction of the pipe fitting is fixedly provided on the pipe mouth, the first positioning part and the limiting part form a positioning assembly, the pipe fitting and the limiting part are respectively fixedly and rotationally connected along the axial direction and circumferential direction of the pipe fitting, and the limiting part abuts against the first positioning part along the radial direction of the pipe fitting.

3. A pipe connection structure according to claim 2, characterized in that: The limiting portion is a hollow columnar body with an opening along its axial direction, and the hollow columnar body is arranged along the tangential direction of the pipe.

4. A pipe connection structure according to claim 3, characterized in that: The hollow columnar body is an elastic cylindrical pin.

5. A pipe connection structure according to claim 3, characterized in that: The limiting parts are symmetrically arranged on both sides of the pipe opening.

6. A pipe connection structure according to claim 2, characterized in that: The first positioning portion is a convex portion protruding outward along the radial direction of the pipe, and the convex portions are evenly arranged along the outer circumferential surface of the pipe.

7. A pipe connection structure according to claim 6, characterized in that: The side of the protrusion away from the axis of the pipe is a plane.

8. A pipe connection structure according to claim 7, characterized in that: The convex parts are symmetrically arranged on the left and right sides of the plane and form an inclined surface with the outer peripheral surface of the pipe.

9. A pipe connection structure according to claim 1, characterized in that: The pipe fitting is provided with a plurality of second positioning portions located on the same outer circumferential surface as the first positioning portion, the diameter of the outer circumferential surface formed on the side of the second positioning portion away from the axis of the pipe fitting is D1, the diameter of the outer circumferential surface formed on the side of the first positioning portion away from the axis of the pipe fitting is D2, the outer circumferential surface formed on the side of the limiting portion close to the axis of the pipe fitting has a maximum diameter D3 and an original diameter D4 due to elastic deformation, and the diameter of the outer circumferential surface of the pipe fitting at the first positioning portion is D5, wherein D3>D1>D2>D4>D5.

10. An electric circular saw, characterized in that: It comprises a casing, a dust exhaust pipe and a pipe fitting connection structure as claimed in any one of claims 1 to 9, wherein the pipe opening is arranged on the casing, and the dust exhaust pipe is fixedly connected to the other end of the pipe fitting.

Images