Tool for positioning and clamping a workpiece

Abstract

A tool for positioning and clamping a workpiece is provided. The tool includes a power input mechanism from which power is input, a lever mechanism connected to the power input mechanism and pivotable about a pivot axis to transmit power from the power input mechanism, an axial motion mechanism that is axially moved by the lever mechanism, a radial clamping mechanism that cooperates with the axial motion mechanism to convert axial motion of the axial motion mechanism into radial motion for positioning and clamping the workpiece, and a base frame that supports the power input mechanism, the lever mechanism, the axial motion mechanism, and the radial clamping mechanism. The axial motion mechanism includes an inclined surface, the radial clamping mechanism includes a spherical surface that abuts and point contacts the inclined surface, and the spherical surface is constrained from axial motion. When the inclined surface is axially moved with the axial motion mechanism, the inclined surface pushes against and moves the spherical surface along the inclined surface relative to the inclined surface to cause the radial clamping mechanism to move radially.

Description

Technical Field

[0001] This invention relates to a tool for positioning and clamping workpieces, particularly shaft-type workpieces. Background Technology

[0002] In the machining industry, tooling fixtures are widely used. Almost all mechanical parts require positioning and clamping during machining or assembly. Especially in the high-precision machining industry, the positioning and clamping of workpieces, particularly shaft-type workpieces, is crucial for completing the machining process and ensuring the quality of the workpiece. The machining of high-precision workpieces often results in workpiece deformation due to low positioning accuracy or unstable clamping force of the fixture, leading to dimensional discrepancies and failure to meet requirements.

[0003] Currently, the widely used workpiece clamps employ a method of directly positioning and clamping the workpiece through the relative movement of two conical surfaces. The disadvantage of this type of clamp is that:

[0004] 1) Because the outer conical surface and the conical hole are in surface contact, and surface contact can cause over-positioning, the positioning accuracy is poor. Additionally, the positioning accuracy of the fixture will decrease if there are protrusions on these two conical surfaces.

[0005] 2) While the radial clamping block clamps the workpiece radially, it generates axial force, which causes the workpiece to be subjected to axial tensile force and deform. Summary of the Invention

[0006] [Technical Issues]

[0007] This invention was made to address the aforementioned problems and other potential technical issues, particularly providing a high-precision tooling fixture mechanism when workpieces require positioning and clamping.

[0008] [Technical Solution]

[0009] According to one aspect of the present invention, a tool is provided for positioning and clamping a workpiece, particularly a shaft-type workpiece. The tool comprises:

[0010] - A power input mechanism from which power for positioning and clamping the workpiece is input;

[0011] - A lever mechanism, which is connected to the power input mechanism and is pivotable about a pivot to transmit power from the power input mechanism;

[0012] - An axial motion mechanism that moves axially under the drive of the lever mechanism;

[0013] - A radial clamping mechanism, which cooperates with the axial motion mechanism, converts the axial motion of the axial motion mechanism into radial motion, so as to position and clamp the workpiece; and

[0014] - A base frame that supports the power input mechanism, the lever mechanism, the axial motion mechanism, and the radial clamping mechanism.

[0015] The axial motion mechanism includes an inclined surface, and the radial clamping mechanism includes a spherical surface. The spherical surface abuts against and makes point contact with the inclined surface, and the spherical surface is restricted from axial movement. When the inclined surface moves axially with the axial motion mechanism, the inclined surface pushes against the spherical surface and causes the spherical surface to move relative to the inclined surface along the inclined surface, thereby causing the radial clamping mechanism to move radially.

[0016] Specifically, the radial clamping mechanism includes a radial clamping block capable of radial movement and a ball, the ball having a spherical surface, one end of the radial clamping block for contacting the workpiece, the other end of the radial clamping block abutting one side of the ball, and the other side of the ball abutting the inclined surface.

[0017] Specifically, the radial clamping block and the ball are capable of moving horizontally, the axial motion mechanism is capable of moving vertically, and the inclined surface is inclined relative to both the horizontal and vertical directions. When the inclined surface moves vertically with the axial motion mechanism, the inclined surface pushes against the ball, and the ball pushes against the radial clamping block, thereby causing the radial clamping block and the ball to move horizontally, thus positioning and clamping the workpiece.

[0018] Optionally, the inclined surface faces upwards at an angle. When the inclined surface moves vertically upwards with the axial motion mechanism, it pushes against the ball, which moves horizontally and pushes against the radial clamping block, which positions and clamps the workpiece. When the inclined surface moves vertically downwards with the axial motion mechanism, the ball and the radial clamping block are released, thereby releasing the workpiece.

[0019] The inclined surface can be an inclined flat surface or an inner conical surface, wherein, preferably, it is an inner conical surface.

[0020] Optionally, a through hole extending horizontally is provided in the base frame, one end of the through hole opening towards the workpiece, and the other end of the through hole opening towards the inclined surface, and the radial clamping block and the ball are disposed in the through hole.

[0021] [Technical Effects]

[0022] The tool for positioning and clamping a workpiece according to the present invention, through its "conical hole-spherical surface" structure, can accurately convert axial force into radial force. Because the spherical surface and the conical surface are in point contact, the clamping force is transmitted through point contact, thus eliminating errors caused by over-positioning and multi-point contact, such as those caused by surface contact, and ensuring high precision of radial displacement and stability of radial clamping force.

[0023] In addition, due to the adoption of the "conical hole-spherical surface" structure, axial force during the clamping process can be eliminated, thereby reducing workpiece deformation.

[0024] Furthermore, since the contact point is within a closed space, the risk of errors caused by impurities entering the contact surface is eliminated, thereby making the workpiece's machining dimensions more stable. Attached Figure Description

[0025] To facilitate understanding of the invention, it is described in more detail below based on exemplary embodiments and in conjunction with the accompanying drawings. The same or similar reference numerals are used in the drawings to denote the same or similar components. It should be understood that the drawings are merely illustrative, and the dimensions and scale of the components in the drawings are not necessarily precise.

[0026] Figure 1 This is a cross-sectional view of a tool for positioning and clamping a workpiece according to an embodiment of the present invention.

[0027] Figure 2 yes Figure 1 A magnified view of region B in the image. Detailed Implementation

[0028] The following will refer to Figure 1 and Figure 2 The specific embodiments of the present invention will be described in detail below. Figure 1 This is a cross-sectional view of a tool for positioning and clamping a workpiece according to an embodiment of the present invention. Figure 2 yes Figure 1 A magnified view of region B in the image.

[0029] [Overall Structure]

[0030] like Figure 1 and Figure 2 As shown, tool 1 according to an embodiment of the present invention is used to position and clamp workpiece 2. Workpiece 2 is, for example, a shaft-like workpiece, or more generally, a cylindrical workpiece. In this embodiment, workpiece 2 is the moving scroll disk of a scroll compressor. Specifically, tool 1 includes:

[0031] - Power input mechanism 11, from which power is input for positioning and clamping workpiece 2;

[0032] - Lever mechanism 12, which is connected to power input mechanism 11 and can pivot about pivot P2 to transmit power from power input mechanism 11;

[0033] - Axial motion mechanism 13, which performs axial motion under the drive of lever mechanism 12 (in Figure 1 and Figure 2 From this perspective, the axis refers to the vertical direction;

[0034] -Radial clamping mechanism 14, which cooperates with axial motion mechanism 13 to convert the axial motion of axial motion mechanism 13 into radial motion, so as to position and clamp workpiece 2;

[0035] - Base frame 15, which supports power input mechanism 11, lever mechanism 12, axial motion mechanism 13, and radial clamping mechanism 14; and

[0036] - Pressure plate mechanism 16, which is used to make the workpiece 2 fit against the positioning surface on the base frame 15.

[0037] Specifically, the power input mechanism 11 includes a screw 111 and a connecting rod 112. The screw 111 has an external thread, and the connecting rod 112 has an internal thread. The external thread of the screw 111 and the internal thread of the connecting rod 112 engage with each other. The screw 111 maintains a constant vertical height due to the support of the base frame 15. When the screw 111 is turned, the connecting rod 112 moves accordingly in the vertical direction. The screw 111 can be a lead screw or other structure known in the art, such as a power input nut.

[0038] Link 112 is connected to lever mechanism 12, which extends generally horizontally, via pivot P1 located at its lower end. Figure 1 In the cross-sectional view shown, pivot P1 is located at the right end of lever mechanism 12, and pivot P2 is located at the left end of lever mechanism 12. As mentioned earlier, lever mechanism 12 can move about pivot P2 along... Figure 1 Pivot in the direction indicated by arrow A. Pivot P2 is fixed to base frame 15.

[0039] The lower end of the axial motion mechanism 13 contacts the lever mechanism 12 at approximately the center position, with the contact point being C1. Thus, when the lever mechanism 12 pivots counterclockwise, the axial motion mechanism 13 moves upward due to the pushing force from the lever mechanism 12 at the contact point C1.

[0040] The axial motion mechanism 13 includes a tray 131. Multiple columns 132 are mounted on the tray 131. Each column 132 has a corresponding slider 133 abutting its top. Thus, when the column 132 moves upward, the slider 133 moves upward due to the pressure from the column 132. When the column 132 moves downward, the slider 132 naturally moves downward. Optionally, a buffer spring 17 is provided between the top of the slider 133 and the base frame 15 to make the movement of the slider 133 smoother.

[0041] The slider 133 has an inclined surface TF, which can be a flat surface inclined relative to both the horizontal and vertical directions. For example... Figure 2 As shown, the inclined surface TF faces diagonally upwards. Alternatively, the inclined surface TF can be an inner conical surface (although in... Figure 1 and Figure 2 In the sectional view shown, the inclined surface TF is displayed as an inclined straight line.

[0042] The radial clamping mechanism 14 includes a ball 20 having a spherical surface S that abuts against and makes point contact with an inclined surface TF. The ball 20 is restricted from vertical movement by a horizontal through-hole 18, which will be described below. When the inclined surface TF moves vertically with the axial movement mechanism 13, the inclined surface TF pushes against the ball S, causing the ball S to move relative to the inclined surface TF along the inclined surface TF, thereby causing the radial clamping mechanism 14 to move radially (i.e., horizontally).

[0043] More specifically, the radial clamping mechanism 14 includes a radial clamping block 21 and a ball 20 capable of radial movement. For example... Figure 2 As shown, sphere 20 has a spherical surface S. The radial inner end of the radial clamping block 21 (in...) Figure 2 The left end of the radial clamping block 21 is used to contact the workpiece 2, and the radial outer end of the radial clamping block 21 is located at the left end. Figure 2 The middle (right end) is against the side of the spherical surface S (in Figure 2 The left side of the sphere (C1) is the contact point. The other side of the sphere S (in...) Figure 2 The middle (right side) abuts against the inclined surface TF, with the contact point being C3. When the axial motion mechanism 13 moves in the vertical direction, the radial clamping block 21 and the ball 20 can move accordingly in the horizontal direction.

[0044] like Figure 2 As shown, a horizontal through hole 18 extending in the horizontal direction is provided in the base frame 15, and one end of the horizontal through hole 18 (in) Figure 2 The opening (left end) faces workpiece 2, and the other end of the horizontal through hole 18 (in...) Figure 2The opening (right end) faces the inclined surface TF. The radial clamping block 21 and the ball 20 are disposed in the horizontal through hole 18, which allows the radial clamping block 21 and the ball 20 to move only in the horizontal direction, while preventing the radial clamping block 21 and the ball 20 from moving in the vertical direction.

[0045] It is understandable that during the vertical upward movement of the inclined surface TF, the force on the ball 20 is perpendicular to the inclined surface TF and angled upwards. The radial clamping block 21, restricted by the horizontal through hole 18, can only move horizontally and not vertically, thus eliminating the axial tension on the workpiece 2 and reducing or even preventing tensile deformation of the workpiece 2. Furthermore, since there are point contacts between the inclined surface TF and the ball 20, and between the ball 20 and the radial clamping block 21, over-positioning and multi-point contact are eliminated, improving positioning accuracy.

[0046] Optionally, a sleeve 19 for fitting the ball 20 into the horizontal through hole 18 is also provided in the horizontal through hole 18. The longitudinal section of the radial clamping block 21 is generally T-shaped. A spring or elastic washer 22 is provided between the radial clamping block 21 and the vertical wall of the horizontal through hole 18. Thus, after the pressure of the inclined surface TF on the ball 20 is released, the radial clamping block 21 moves horizontally under the action of the elastic washer 22, thereby releasing the workpiece 2. When the inclined surface TF moves vertically upward with the axial motion mechanism 13, the inclined surface TF pushes the ball 20, and the ball 20 pushes the radial clamping block 21, thereby causing the radial clamping block 21 and the ball 20 to move horizontally (in Figure 2 (The movement is to the left). In this way, the radial clamping block 21 pushes the workpiece 2, thereby positioning and clamping the workpiece 2.

[0047] It should be understood that, despite Figure 1 and Figure 2 The diagram shows only one set of radial clamping blocks 21 and spheres 20, but in practice, multiple sets of radial clamping blocks 21 and spheres 20 can be set according to specific application requirements.

[0048] Preferably, the contact point C1 between the lever mechanism 12 and the axial motion mechanism 13, the contact point C2 between the ball 20 and the radial clamping block 21, and the contact point C3 between the inclined surface TF and the ball 20 are located in a sealed space. This prevents external impurities from entering and affecting the positioning accuracy.

[0049]

Operation Method

[0050] First, with tool 1 in the open / closed state, place workpiece 2 on the base 15 of workpiece 1, so that workpiece 2 abuts against the positioning surface on the base 15, and insert the part of tool 2 to be positioned and clamped into the axial movement mechanism 13. Then, use the pressure plate mechanism 16 to initially clamp workpiece 2. That is, make workpiece 2 as... Figure 1 It is placed on tool 1 as shown, but it is not yet fully positioned and clamped.

[0051] Then, as Figure 1 and Figure 2 As shown, power is input from the power input mechanism 11 (i.e., turning the screw 111), causing the power connecting rod 112 to move upward. The lever mechanism 12, driven by the connecting rod 112, pivots counterclockwise around pivot P2, thereby lifting the axial motion mechanism 13 upward. When the inclined surface TF moves vertically upward with the axial motion mechanism 13, the inclined surface TF pushes against the ball 20, and the ball 20 moves horizontally and pushes against the radial clamping block 21, which positions and clamps the workpiece 2. Thus, the positioning and clamping of the workpiece 2 are completed.

[0052] When the screw 111 is turned in the opposite direction, the power connecting rod 112 moves downward, the axial motion mechanism 13 also moves vertically downward, and the inclined surface TF moves vertically downward along with the axial motion mechanism 13. In this way, the ball 20 and the radial clamping block 21 are released, thereby releasing the workpiece 2.

[0053] Although the technical objectives, solutions, and effects of the present invention have been described in detail above with reference to specific embodiments, it should be understood that the above embodiments are merely exemplary and not restrictive. Therefore, any modifications, equivalent substitutions, or improvements made by those skilled in the art within the essential spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A tool (1) for positioning and clamping a workpiece (2), the tool comprising: - A power input mechanism (11) from which power for positioning and clamping the workpiece is input; - A lever mechanism (12) connected to the power input mechanism and capable of pivoting about a fixed pivot (P2) to transmit power from the power input mechanism; - Axial motion mechanism (13), which moves axially in the vertical direction under the drive of the lever mechanism; - A radial clamping mechanism (14), which cooperates with the axial motion mechanism; and - Base frame (15), which supports the power input mechanism, the lever mechanism, the axial motion mechanism and the radial clamping mechanism. The axial motion mechanism is provided with an inclined surface (TF) that is inclined relative to the horizontal and vertical directions, and the inclined surface moves with the axial motion mechanism in the vertical direction; The radial clamping mechanism includes a sphere (20) and a radial clamping block (21) disposed within the base frame. The sphere has an outer spherical surface (S). The radial outer end of the radial clamping block is used to contact the workpiece, and the radial inner end of the radial clamping block abuts against the first side of the spherical surface. The base frame forms a through hole (18) extending in the horizontal direction. The sphere and the radial clamping block are both housed in the through hole and guided by the through hole wall, allowing only radial movement in the horizontal direction and restricting the axial displacement of the sphere in the vertical direction. The spherical surface abuts against the inclined surface and is in point contact with the inclined surface, and the spherical surface is also in point contact with the radial clamping block; when the inclined surface moves vertically with the axial motion mechanism, the inclined surface pushes the spherical surface to make it move relative to the inclined surface, and the spherical surface drives the radial clamping block to move horizontally toward the workpiece to achieve radial clamping. The through hole and the surrounding structure together cooperate with the inclined surface to form a closed space, and at least the two point contacts are located within the closed space to prevent external impurities from entering the contact area and to stabilize the positioning and clamping accuracy.

2. The tool according to claim 1, wherein, The inclined surface faces diagonally upwards. When the inclined surface moves vertically downward with the axial motion mechanism, the ball and the radial clamping block are released, thereby releasing the workpiece.

3. The tool according to claim 1 or 2, wherein, The inclined surface is an inclined flat surface or an inner conical surface.

4. The tool according to claim 1, wherein, One end of the through hole faces the workpiece, and the other end of the through hole faces the inclined surface.

5. The tool according to claim 1, wherein, The workpiece is a shaft-type workpiece.

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