A large internal ratchet machining method

Abstract

The application discloses a large internal ratchet wheel machining method, which comprises the following steps: S1, rotating a machine tool B shaft; S2, tooling a ball cutter (4) installed on the machine tool B shaft accessory with any two points on a large tooth surface of a tooling slot and any one point on a small tooth surface respectively to obtain coordinate values of each tooling point in a cutter tip coordinate system; S3, according to the intersection of a tooth root virtual circle under the cutter tip coordinate system and the connecting line of the two tooling points on the large tooth surface, the intersection point constitutes the coordinate values of a tooth root vertex in the cutter tip coordinate system, and the coordinate values of the tooth root vertex in the cutter tip coordinate system and the offset of the cutter tip coordinate system relative to a part coordinate system are obtained according to a trigonometric function relationship; and S4, the offset is used for compensating the cutter tip position deviation generated by the rotation of the machine tool B shaft. The technical effect of the application is that qualified large internal ratchet wheels are machined by compensating the cutter tip position deviation and the part tooth slot phase deviation, qualified large internal ratchet wheels are machined on a machine tool by using a common ball cutter, and production cost is saved.

Description

Technical Field

[0001] This invention relates to the technical field of machining methods, and in particular to a method for machining large internal ratchet. Background Technology

[0002] Large internal ratchet wheels are mainly used in the metallurgical industry and are core components of the synchronous operation mechanism in metallurgical crane reducers. Due to their unidirectional meshing and limiting characteristics, they are widely used in the lifting field. In recent years, due to increasingly higher requirements for their load-bearing capacity, the design of the parts often requires a larger contact area at the ratchet and pawl mating point (e.g., wider tooth width, smaller tooth root radius, etc.).

[0003] Because large internal ratchet teeth are wide, with one side being a web, and the relief groove between the ratchet teeth and the web is narrow, ratchet hobbing and wire EDM cannot be used for machining. They are mostly machined on boring and milling machines or slotting machines. Existing machining methods have the following drawbacks: For parts with wide teeth and small fillet radius, specially customized extended tools are used. However, the insufficient rigidity of these extended tools leads to lower machining accuracy and poor surface finish. Using forming tools is not only costly but also prone to tip wear, resulting in reduced tooth height, larger tooth root fillet radius, and a smaller contact area between the ratchet and pawl. Summary of the Invention

[0004] The purpose of this invention is to provide a method for machining large internal ratchet wheels. By compensating for the deviation of the tool tip position, a qualified large internal ratchet wheel can be machined. Instead of machining a large internal ratchet wheel with a forming tool, a qualified large internal ratchet wheel can be machined on a machine tool using a common ball end mill, thus saving production costs.

[0005] To achieve the aforementioned objectives, the present invention adopts the following technical solution.

[0006] A method for machining a large internal ratchet includes the following steps:

[0007] S1: B-axis of a rotary machine tool;

[0008] S2: Set the ball end mill mounted on the B-axis attachment of the machine tool to any two points on the large tooth surface and any point on the small tooth surface, and obtain the coordinate values ​​of each setting point in the tool tip coordinate system;

[0009] S3: The intersection of the line connecting the virtual circle of the tooth root in the tool tip coordinate system and the two tool setting points on the large tooth surface constitutes the coordinate value of the tooth root vertex in the tool tip coordinate system. The coordinate value of the tooth root vertex in the tool tip coordinate system and the offset of the tool tip coordinate system relative to the part coordinate system are obtained according to the trigonometric function relationship.

[0010] S4: This offset is used to compensate for the tool tip position deviation caused by the rotation of the machine tool's B-axis.

[0011] The present invention, employing the aforementioned technical solution, obtains the coordinate values ​​of each tool-setting point in the tool tip coordinate system by setting the ball end mill mounted on the B-axis accessory of the machine tool to any two points on the large tooth surface and any point on the small tooth surface. The virtual circle of the tooth root in the tool tip coordinate system intersects the line connecting the two tool-setting points on the large tooth surface, forming a triangle with the points on the large tooth surface, the points on the small tooth surface, and the line connecting the tooth root. This triangle facilitates the acquisition of trigonometric function relationships, which in turn yield the coordinate values ​​of the tooth root vertex in the tool tip coordinate system. The offset of the tool tip coordinate system relative to the part coordinate system is then calculated using a compensation relationship. This offset is used to compensate for the tool tip position deviation caused by the rotation of the B-axis of the machine tool. By compensating for the tool tip position deviation, a qualified large internal ratchet is machined. The large internal ratchet is machined on the machine tool using a common ball end mill instead of using a form cutter or end mill, saving production costs and preventing the machined tooth root arc from exceeding the design value, thus reducing the contact area between the ratchet and pawl and affecting the load-bearing capacity of the internal ratchet.

[0012] Preferably, the phase compensation value of the component is obtained through a relational expression, which is as follows:

[0013]

[0014] in, This is the phase compensation value for the component. The angle between the theoretical large tooth surface and the theoretical tooth space phase line. The theoretical tooth cogging phase value, in the tool tip coordinate system. The coordinates of the first pair of tool points on the large tooth surface (11) are P1(x1,y1) and the coordinates of the second pair of tool points on the large tooth surface (11) are P2(x2,y2).

[0015] In this way, the phase compensation value of the part, that is, the phase deviation value between the actual tooth groove and the theoretical tooth groove, is obtained through the above relationship. By compensating for the phase deviation value between the actual tooth groove and the theoretical tooth groove during machining, the machining quality of the part is guaranteed.

[0016] Preferably, the tool tip coordinate system is obtained according to the trigonometric function relationship. The coordinates of the zero point (x0, y0) and the coordinates of the tooth root S (xs, ys) are given by the following trigonometric function relationship:

[0017]

[0018]

[0019]

[0020]

[0021]

[0022] In the tool tip coordinate system The coordinates of the root of the lower cutting edge are S(xs, ys). This is the phase compensation value for the component. P1(x1,y1) represents the theoretical tooth cogging phase value, and P1(x1,y1) represents the phase value in the tool tip coordinate system. The coordinates of the first tooling point on the large tooth face are given by P2(x2,y2), the coordinates of the second tooling point on the large tooth face are given by P3(x3,y3), the coordinates of the tooling point on the small tooth face are given by S(xs,ys), the coordinates of the tooth root are given by S(xs,ys), and R is the radius of the ball end mill. It is the angle between the theoretical large tooth surface and the theoretical small tooth surface.

[0023] Thus, the tool tip coordinate system is obtained through the above trigonometric function relationships. The coordinates (x0, y0) of the zero point are used to obtain the tool tip position deviation (x0, y0) caused by the rotation of the B-axis of the machine tool, which is the offset of the tool tip coordinate system relative to the workpiece coordinate system. By compensating for the tool tip position deviation, a qualified large internal ratchet is machined. A qualified large internal ratchet is machined on the machine tool using a regular ball end mill instead of machining a large internal ratchet using a forming cutter.

[0024] Preferably, the axis vector of the ball cutter after the B-axis of the machine tool rotates is... Let α be the angle between the machine tool and the horizontal plane. When α ≤ arctan((D2-D1) / 2 / L1) and the machine tool B-axis attachment just interferes with the plate, α can be obtained through the following relationship:

[0025] (LT+L1) ×sinα- D2 / 2*cosα =h,

[0026] Where LT is the ball end mill extension length, L1 is the tool holder extension length, D1 is the tool holder diameter, D2 is the diameter of the machine tool B-axis accessory, and h is the width of the relief groove.

[0027] Thus, the axis vector of the ball cutter after the machine tool's B-axis rotates... Let α be the angle between the machine tool and the horizontal plane. When α satisfies the inequality α≤arctan((D2-D1) / 2 / L1) and the machine tool B-axis attachment and the web plate just interfere, α can be calculated using the relationship α≤arctan((D2-D1) / 2 / L1). The calculated value of α is the value at which the machine tool B-axis attachment and the web plate will interfere during machining. Therefore, to prevent interference between the machine tool B-axis attachment and the web plate during machining, the value of α needs to be greater than the value calculated by the above relationship.

[0028] Preferably, the axis vector of the ball cutter after the B-axis of the machine tool rotates is... Let α be the angle between the tool holder and the horizontal plane. When α > arctan((D2-D1) / 2 / L1) and the tool holder just interferes with the tool plate, α can be obtained through the following relationship:

[0029] LT×sinα - D1 / 2*cosα =h

[0030] Where LT is the ball end mill extension length, L1 is the tool holder extension length, D1 is the tool holder diameter, D2 is the diameter of the machine tool B-axis accessory, and h is the width of the relief groove.

[0031] Thus, the axis vector of the ball cutter after the machine tool's B-axis rotates... Let α be the angle between the tool holder and the horizontal plane. When α satisfies the inequality α>arctan((D2-D1) / 2 / L1) and the tool holder and the blade just interfere, the value of α can be calculated using the relationship LT×sinα- D1 / 2*cosα=h. The calculated value of α is the value at which the tool holder and the blade will interfere during machining. Therefore, to prevent the tool holder and the blade from interfering during machining, the value of α needs to be greater than the value calculated by the above relationship.

[0032] Preferably, the rotation angle β of the machine tool B axis in step s1 is obtained through the following set of relationships:

[0033]

[0034]

[0035]

[0036] Where T1 is a rotation matrix that rotates 45° counterclockwise along the x-axis, and T2 is a rotation matrix that rotates by an angle β along the z-axis. Let α be the inverse matrix of T1, and α be the axis vector of the ball cutter (4) after the B-axis of the machine tool rotates. The angle with the horizontal plane, This is the initial axis vector of the ball cutter.

[0037] In this way, the rotation angle β of the machine tool B-axis can be obtained through the above relationship, which makes it easy to input the rotation angle β of the machine tool B-axis through programming during actual machining, so as to ensure the accuracy of the machined internal ratchet dimensions and the machining quality of the internal ratchet.

[0038] Preferably, the machine tool B-axis accessory, tool holder, and ball end mill must not interfere with the machining head during processing.

[0039] This ensures that the machine tool's B-axis accessories, tool holder, and ball end mill do not interfere with the machining head during processing, facilitating smooth machining while meeting the machining accuracy requirements of the internal ratchet.

[0040] Preferably, when programming the machine tool, the phase compensation value of the compensation component and the offset caused by the rotation of the machine tool's B-axis are considered simultaneously.

[0041] In this way, by simultaneously considering the phase compensation value of the compensation component and the offset caused by the rotation of the machine tool's B-axis during machine tool programming, the quality of the machined internal ratchet is guaranteed.

[0042] The beneficial effects of this invention are as follows: By setting the ball end mill mounted on the B-axis attachment of the machine tool with any two points on the large tooth surface and any point on the small tooth surface, the coordinate values ​​of each setting point in the tool tip coordinate system are obtained. The virtual circle of the tooth root in the tool tip coordinate system intersects the line connecting the two setting points on the large tooth surface. A triangle is formed by the points on the large tooth surface, the points on the small tooth surface, and the line connecting the tooth root. This triangle facilitates the acquisition of trigonometric function relationships. The coordinate values ​​of the tooth root vertex in the tool tip coordinate system are obtained through the trigonometric function relationships. Then, the offset of the tool tip coordinate system relative to the part coordinate system is calculated through the compensation relationship. This offset is used to compensate for the tool tip position deviation caused by the rotation of the B-axis of the machine tool. Furthermore, the phase compensation value of the part, i.e., the phase deviation value between the actual tooth groove and the theoretical tooth groove, is obtained by setting the relationship. By compensating for the phase deviation value of the part during machining, the machining quality of the part is guaranteed. Using a standard ball end mill to machine a qualified large internal ratchet on a machine tool instead of machining a large internal ratchet with a form cutter or end mill can save production costs and prevent the machined tooth root radius from being larger than the design value, reducing the contact area at the ratchet and pawl mating point and affecting the load-bearing capacity of the internal ratchet. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the processing of the present invention;

[0044] Figure 2 This is a schematic diagram of the tooth surface and tooth tip in the tool tip coordinate system and the part coordinate system of the present invention;

[0045] Figure 3 For the present invention Figure 2 An enlarged view of part M in the image;

[0046] Figure 4 For the present invention Figure 1 The cross-sectional view of AA in the diagram. Detailed Implementation

[0047] The present invention will be further described below with reference to the accompanying drawings, but this does not limit the invention to the scope of the embodiments described.

[0048] The reference numerals in the accompanying drawings include: internal ratchet 1, large tooth surface 11, small tooth surface 12, web plate 13, tool relief groove 14, machine tool B-axis accessory 2, tool holder 3, ball end mill 4, theoretical tooth groove 5, tool setting tooth groove 51, and virtual circle at the tooth root 53.

[0049] Example 1, such as Figures 1 to 4 As shown; a method for machining a large internal ratchet includes the following steps:

[0050] S1: B-axis of a rotary machine tool;

[0051] S2: Set the ball cutter 4, which is mounted on the B-axis accessory 2 of the machine tool, to any two points on the large tooth surface 11 and any point on the small tooth surface 12 respectively, and obtain the coordinate values ​​of each tool setting point in the tool tip coordinate system;

[0052] S3: The line connecting the virtual circle 53 of the tooth root in the tool tip coordinate system and the two tool setting points on the large tooth surface 11 intersects, and the intersection point forms the coordinate value of the tooth root vertex of the tool setting tooth groove 51 in the tool tip coordinate system. The coordinate value of the tooth root vertex in the tool tip coordinate system and the offset of the tool tip coordinate system relative to the part coordinate system are obtained according to the trigonometric function relationship.

[0053] S4: This offset is used to compensate for the tool tip position deviation caused by the rotation of the machine tool's B-axis.

[0054] See Figures 1 to 4 The phase compensation value of the part is obtained through the following formula:

[0055]

[0056] in, For the phase compensation value of the part, the parameters in the theoretical tooth groove 5 are: The angle between the large tooth surface and the theoretical tooth space phase line. Given the theoretical tooth groove phase value, the parameters under tooth groove 51 are: in the tool tip coordinate system The coordinates of the first tool pairing point on the large tooth surface 11 are P1(x1,y1), and the coordinates of the second tool pairing point on the large tooth surface 11 are P2(x2,y2). Thus, the phase compensation value of the part is obtained through the above relationship. By considering the phase compensation value of the part during machining, the machining quality of the part is guaranteed.

[0057] See Figure 2 The tool tip coordinate system is obtained based on trigonometric function relationships. The coordinates of the zero point (x0, y0) and the coordinates of the tooth root S (xs, ys) are given by the following trigonometric function relationship:

[0058]

[0059]

[0060]

[0061]

[0062]

[0063] In the tool tip coordinate system The coordinates of the root of the lower cutting tooth are S(xs,ys). This is the phase compensation value for the component. P1(x1,y1) represents the theoretical tooth cogging phase value, and P1(x1,y1) represents the phase value in the tool tip coordinate system. The coordinates of the first tooling point on the large tooth face are given by P2(x2,y2), the coordinates of the second tooling point on the large tooth face are given by P3(x3,y3), the coordinates of the tooling point on the small tooth face are given by S(xs,ys), the coordinates of the tooth root are given by S(xs,ys), and R is the radius of the ball end mill. The angle between the theoretical large tooth surface and the theoretical small tooth surface is given by the above trigonometric function relationship. The tool tip coordinate system is then obtained. Below The point coordinates (x0, y0) are used to obtain the positional deviation (x0, y0) caused by the attachment and the rotation of the machine tool's B axis, which is the offset of the tool tip coordinate system relative to the part coordinate system XOY. By compensating for the tool tip positional deviation, a qualified large internal ratchet is machined. A qualified large internal ratchet is machined on the machine tool using a regular ball end mill instead of machining the large internal ratchet using a forming cutter.

[0064] See Figures 2 to 4 The axis vector of the ball cutter (4) after the B-axis of the machine tool rotates The angle between the machine tool and the horizontal plane is α. When α ≤ arctan((D2-D1) / 2 / L1) and the machine tool B-axis attachment (2) just interferes with the web plate (13), α is obtained through the following relationship:

[0065] (LT+L1) ×sinα- D2 / 2*cosα =h,

[0066] Where LT is the ball cutter extension length, L1 is the tool holder extension length, D1 is the tool holder diameter, D2 is the diameter of the machine tool B-axis accessory 12, and h is the width of the relief groove. The axial vector of the ball cutter 4 after the machine tool B-axis rotates... Let α be the angle between the machine tool and the horizontal plane. When α satisfies the inequality α≤arctan((D2-D1) / 2 / L1), and the machine tool B-axis attachment and the web plate 13 just interfere, α is calculated using the relationship α≤arctan((D2-D1) / 2 / L1). The calculated α value is the point value at which the machine tool B-axis attachment 2 and the web plate will interfere during machining. Therefore, to prevent interference between the machine tool B-axis attachment 2 and the web plate during machining, it is necessary to make... The value is greater than the value calculated by the above formula to prevent interference between the machine tool B-axis accessory 2 and the plate during processing.

[0067] See Figure 4The axis vector of the ball cutter 4 after the B-axis of the machine tool rotates. Let α be the angle between the tool holder and the horizontal plane. When α > arctan((D2-D1) / 2 / L1) and the tool holder just interferes with the tool plate, the following relationship can be obtained. :

[0068] LT×sinα - D1 / 2xcosα =h

[0069] Where LT is the ball cutter extension length, L1 is the tool holder extension length, D1 is the tool holder diameter, D2 is the diameter of the machine tool B-axis accessory 2, and h is the width of the relief groove. The axial vector of the ball cutter 4 after the machine tool B-axis rotates... Let α be the angle between the tool holder 3 and the horizontal plane. When α satisfies the inequality α > arctan((D2-D1) / 2 / L1), and the tool holder 3 and the web plate 13 just interfere, the value of α can be calculated using the relationship LT×sinα - D1 / 2*cosα =h. The calculated value of α is the point at which the tool holder 3 and the web plate 13 will interfere during machining. Therefore, to prevent interference between the tool holder 3 and the web plate 13 during machining, it is necessary to make... The value is greater than that calculated by the above formula. This value is used to prevent the tool holder 3 from interfering with the blade 13 during machining.

[0070] See Figure 4 The rotation angle of the machine tool's B-axis can be obtained through the following set of equations. ,

[0071]

[0072]

[0073]

[0074] Where T1 is a rotation matrix that rotates 45° counterclockwise along the x-axis, and T2 is a rotation matrix that rotates by an angle β along the z-axis. for The inverse matrix, where α is the axis vector of the ball cutter after the B-axis of the machine tool rotates. The angle with the horizontal plane, Let this be the initial axis vector of the ball end mill 4. Thus, the rotation angle of the machine tool's B-axis can be obtained through the above relationship. This allows for easy input of the machine tool's B-axis rotation angle via programming during actual machining. This ensures that the dimensions of the machined internal ratchet are accurate and guarantees the machining quality of the internal ratchet.

[0075] The machine tool B-axis attachment 2, tool holder 3, and ball end mill 4 must not interfere with the machine tool's web plate 13 during machining. This ensures smooth machining while meeting the required machining accuracy for the inner ratchet 1. During machine tool programming, both the phase compensation value of the compensating parts and the offset caused by the machine tool's B-axis rotation are considered. Thus, by simultaneously considering both the phase compensation value of the compensating parts and the offset caused by the machine tool's B-axis rotation during machine tool programming, the quality of the machined inner ratchet 1 is guaranteed.

[0076] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A method for machining a large internal ratchet, characterized in that, Includes the following steps: S1: B-axis of a rotary machine tool; S2: Set the ball cutter (4) installed on the B-axis accessory (2) of the machine tool to any two points on the large tooth surface (11) and any point on the small tooth surface (12) of the tool setting tooth groove (51) respectively, and obtain the coordinate value of each tool setting point in the tool tip coordinate system; S3: The line connecting the virtual circle (53) of the tooth root in the tool tip coordinate system and the two tool-setting points on the large tooth surface (11) intersects, and the intersection point constitutes the coordinate value of the tooth root vertex in the tool tip coordinate system. The coordinate value of the tooth root vertex in the tool tip coordinate system and the offset of the tool tip coordinate system relative to the part coordinate system are obtained according to the trigonometric function relationship. The tool tip coordinate system is obtained according to the trigonometric function relationship. The coordinates of the zero point (x0, y0) and the coordinates of the tooth root S (xs, ys) are given by the following trigonometric function relationship: In the tool tip coordinate system The coordinates of the root of the lower cutting edge are S(xs, ys). This is the phase compensation value for the component. P1(x1,y1) represents the theoretical tooth cogging phase value, and P1(x1,y1) represents the phase value in the tool tip coordinate system. The coordinates of the first tooling point on the large tooth face are given by P2(x2,y2), the coordinates of the second tooling point on the large tooth face are given by P3(x3,y3), the coordinates of the tooling point on the small tooth face are given by S(xs,ys), the coordinates of the tooth root are given by S(xs,ys), and R is the radius of the ball end mill. The angle between the theoretical large tooth surface and the theoretical small tooth surface; The phase compensation value of the component is obtained through a relational expression, which is as follows: in, This is the phase compensation value for the component. The angle between the theoretical large tooth surface and the theoretical tooth space phase line. The theoretical tooth cogging phase value, in the tool tip coordinate system The coordinates of the first pair of tool points on the large tooth surface (11) are P1(x1,y1) and the coordinates of the second pair of tool points on the large tooth surface (11) are P2(x2,y2). S4: The offset is used to compensate for the tool tip position deviation caused by the rotation of the machine tool B axis.

2. The method for machining large internal ratchet according to claim 1, characterized in that, The axis vector of the ball cutter (4) after the B-axis of the machine tool rotates The angle between the machine tool and the horizontal plane is α. When α ≤ arctan((D2-D1) / 2 / L1) and the machine tool B-axis attachment (2) just interferes with the web plate (13), α is obtained through the following relationship: (LT+L1) ×sinα- D2 / 2*cosα =h, Where LT is the extension length of the ball cutter (4), L1 is the extension length of the tool holder (3), D1 is the diameter of the tool holder (3), D2 is the diameter of the machine tool B-axis accessory (2), and h is the width of the relief groove (14).

3. The method for machining large internal ratchet according to claim 1, characterized in that, The axis vector of the ball cutter (4) after the B-axis of the machine tool rotates The angle between the tool holder (3) and the horizontal plane is α. When α > arctan((D2-D1) / 2 / L1) and the tool holder (3) just interferes with the blade (13), α is obtained through the following relationship: LT×sinα - D1 / 2*cosα =h Where LT is the extension length of the ball cutter (4), L1 is the extension length of the tool holder (3), D1 is the diameter of the tool holder (3), D2 is the diameter of the machine tool B-axis accessory (2), and h is the width of the relief groove (14).

4. The method for machining a large internal ratchet according to claim 2 or 3, characterized in that, The rotation angle β of the machine tool's B axis in step s1 is obtained through the following set of relationships. Where T1 is a rotation matrix that rotates 45° counterclockwise along the x-axis, and T2 is a rotation matrix that rotates by an angle β along the z-axis. Let T1 be the inverse matrix. Let be the initial axis vector of the ball cutter (4).

5. The method for machining large internal ratchet according to claim 1, characterized in that, The machine tool B-axis attachment (2), tool holder (3) and ball cutter (4) must not interfere with the web plate (13) during processing.

6. The method for machining a large internal ratchet according to claim 1, characterized in that, When programming the machine tool, both the phase compensation value of the compensation component and the offset caused by the rotation of the machine tool's B-axis are taken into account.

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