A CNC machining center clamping jig

Abstract

The application discloses a CNC machining center clamping jig, which comprises a bottom plate, a top plate, a plurality of uniformly distributed through holes formed in the top plate, a support rod, a support mechanism arranged in the through hole and a clamping mechanism arranged on the bottom plate. The CNC machining center clamping jig can realize self-adaptive multi-point contour following support of the bottom surface of a complex curved surface or a special-shaped workpiece through the independent driving of the plurality of support mechanisms, and can avoid workpiece suspension or overload deformation caused by uneven support height.

Description

Technical Field

[0001] This invention relates to the field of machining center technology, and in particular to a clamping fixture for a CNC machining center. Background Technology

[0002] Before machining a workpiece in a CNC machining center, it needs to be positioned and fixed using a clamping fixture. Common clamping fixtures typically employ rigid support and clamping, where several support columns or blocks of fixed height support the bottom surface of the workpiece, and then flat-jaw vises or pressure plates on both sides directly clamp the workpiece sidewalls horizontally. For thin-walled parts, irregularly shaped parts, or workpieces with complex curved surfaces, rigid support struggles to adapt to variations in the workpiece's bottom surface, resulting in some support points being suspended or overloaded. Under clamping force, the workpiece is prone to elastic deformation, leading to springback after machining and severely impacting machining accuracy. Furthermore, rigid clamping mechanisms cannot adapt to irregular contours of the workpiece sidewalls, often achieving only point or line contact, resulting in a small clamping area, high local pressure, and potential damage to the workpiece surface.

[0003] Therefore, it is necessary to provide a new CNC machining center clamping fixture to solve the above-mentioned technical problems. Summary of the Invention

[0004] To solve the above-mentioned technical problems, the present invention provides a clamping fixture for CNC machining centers.

[0005] The present invention provides a CNC machining center clamping fixture, including a base plate, and further comprising: A top plate, wherein a plurality of evenly distributed through holes are provided on the top plate; A support rod is provided, and the base plate is fixedly connected to the top plate via the support rod. A support mechanism is disposed within the through hole; A clamping mechanism is provided on the base plate; The support mechanism includes a fixed cylinder, a support head, a first drive unit, and a positioning switch. The fixed cylinder is fixedly disposed in the through hole, the support head is slidably connected to the fixed cylinder, the first drive unit is installed in the fixed cylinder and is used to drive the support head to rise and fall, and the positioning switch is disposed on the top of the support head and is electrically connected to the first drive unit.

[0006] Preferably, the clamping mechanism includes: The second drive unit is fixedly mounted on the top of the base plate; The second screw, the second drive unit is connected to the second screw and drives it to rotate, the second screw has two threaded segments with opposite thread directions; The second guide rod is fixedly mounted on the base plate and parallel to the second screw; Two sliding plates are respectively threaded to two threaded sections of the second screw, and both sliding plates are slidably connected to the second guide rod; A clamping assembly is provided on each of the aforementioned slides.

[0007] Preferably, the first drive unit includes a first motor, a first screw, and a first guide rod. The first motor is installed inside the fixed cylinder, the first screw is fixedly connected to the output shaft of the first motor, and the first screw is threadedly connected to the support head. The first guide rod is fixedly installed inside the fixed cylinder, and the support head is slidably connected to the first guide rod.

[0008] Preferably, the clamping assembly includes: A mounting slot is provided on the slide plate; Multiple sliding grooves are provided at the bottom of the mounting groove, and a sliding rod is slidably connected in each sliding groove; Limiting plates are provided at both ends of the slide rod; A spring is disposed between the sliding plate and the limiting plate; The pressure plate is slidably connected within the mounting groove; An electric actuator is mounted on the slide plate, and the bottom of the electric actuator is fixedly connected to the pressure plate, which is used to drive the pressure plate to press against the top of the slide rod.

[0009] Preferably, there are multiple support mechanisms, and the multiple support mechanisms are arranged corresponding to the multiple through holes.

[0010] Preferably, the second drive unit is a second motor, which is mounted on the base plate, and the output shaft of the second motor is fixedly connected to the second screw.

[0011] Preferably, the top of the slide bar abuts against the bottom surface of the pressure plate.

[0012] Preferably, the spring is sleeved on the slide rod, and the two ends of the spring abut against the slide plate and the limiting plate, respectively.

[0013] Compared with related technologies, the CNC machining center clamping fixture provided by this invention has the following beneficial effects: This invention provides a CNC machining center clamping fixture. By incorporating multiple independently driven support mechanisms, each support head can automatically rise and fall to a position contacting the bottom surface of the workpiece under the control of a position switch. This achieves adaptive multi-point conformal support for complex curved surfaces or irregularly shaped workpieces, avoiding workpiece suspension or overload deformation caused by uneven support height. Simultaneously, the clamping mechanism employs a clamping assembly with multiple floating slide rods. Each slide rod can independently compress a spring according to the local contour of the workpiece's sidewall, generating different extension lengths to form a conformal contact. A pressure plate then locks the rod in place, transforming point contact into large-area surface contact clamping. This increases the clamping area, reduces local pressure, and prevents workpiece surface damage. The support and clamping mechanisms achieve adaptive conformal clamping of the workpiece from both the bottom and sidewall directions, reducing clamping stress. This is suitable for machining easily deformable workpieces such as thin-walled and irregularly shaped parts, and helps improve machining accuracy and yield. Attached Figure Description

[0014] Figure 1 This is a three-dimensional structural diagram of the CNC machining center clamping fixture provided by the present invention; Figure 2 A schematic diagram of the support mechanism structure provided by the present invention; Figure 3 A schematic diagram of the clamping mechanism structure provided by the present invention; Figure 4 This is a schematic diagram of the slide bar structure provided by the present invention.

[0015] The following are the labels in the diagram: 1. Base plate; 2. Support rod; 3. Top plate; 4. Through hole; 5. Support mechanism; 6. Clamping mechanism; 7. Fixed cylinder; 8. Support head; 9. First motor; 10. First screw; 11. First guide rod; 12. Position switch; 13. Second motor; 14. Second screw; 15. Second guide rod; 16. Slide plate; 17. Clamping assembly; 18. Mounting groove; 19. Slide groove; 20. Slide rod; 21. Limiting plate; 22. Spring; 23. Pressure plate; 24. Electric actuator. Detailed Implementation

[0016] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0017] In the specific implementation process, such as Figures 1-4 As shown, a CNC machining center clamping fixture includes a base plate 1, a top plate 3, and a support rod 2 connecting the two. The base plate 1 is fixedly connected to the top plate 3 through the support rod 2. The top plate 3 has several evenly distributed through holes 4, and a support mechanism 5 is provided in each through hole 4. The base plate 1 is provided with a clamping mechanism 6 for clamping the workpiece.

[0018] There are multiple support mechanisms 5, each corresponding to a through hole 4. Each support mechanism 5 includes a fixed cylinder 7, a support head 8, a first drive unit, and a position switch 12. The fixed cylinder 7 is fixedly installed inside the through hole 4. The support head 8 is slidably connected inside the fixed cylinder 7. The first drive unit is installed inside the fixed cylinder 7 and is used to drive the support head 8 to move up and down within the fixed cylinder 7. The first drive unit includes a first motor 9, a first screw 10, and a first guide rod 11. The first motor 9 is fixedly installed at the bottom of the fixed cylinder 7, and its output shaft is vertically upward and fixedly connected to the first screw 10. The first screw 10 is threaded into a threaded hole at the bottom of the support head 8. The first guide rod 11 is fixedly installed inside the fixed cylinder 7 and is vertically positioned. The support head 8... One side of the support head 8 slides with the first guide rod 11 to guide the lifting and lowering movement of the support head 8 and prevent it from rotating. The position switch 12 is located on the top of the support head 8 and is electrically connected to the first motor 9. When the workpiece is placed on the top plate 3, the support head 8 rises under the drive of the first motor 9 until the position switch 12 touches the bottom of the workpiece. The position switch 12 then sends a signal to control the first motor 9 to stop working. At this time, the support head 8 just contacts the bottom surface of the workpiece and provides support. Multiple independent support mechanisms 5 are provided. Each support head 8 can automatically adjust its extension height according to the concave and convex shape of the bottom surface of the workpiece, thereby realizing adaptive multi-point support for complex curved workpieces or irregularly shaped workpieces and effectively avoiding deformation of the workpiece caused by uneven support points.

[0019] The clamping mechanism 6 is mounted on the base plate 1 and is used to clamp the workpiece horizontally. The clamping mechanism 6 includes a second drive unit, a second screw 14, a second guide rod 15, two slide plates 16, and a clamping assembly 17. The second drive unit is a second motor 13, which is fixedly mounted on the top side of the base plate 1. The second screw 14 is horizontally positioned, with one end fixedly connected to the output shaft of the second motor 13 and driven to rotate by the second motor 13. The second screw 14 has two threaded sections with opposite thread directions, namely a left-hand thread section and a right-hand thread section. The second guide rod 15 is fixedly mounted on the base plate 1 and is parallel to the second screw 14. Two sliding plates 16 are threadedly connected to the two threaded sections of the second screw 14, and the two sliding plates 16 are simultaneously slidably connected to the second guide rod 15. When the second motor 13 drives the second screw 14 to rotate, the two sliding plates 16 will move closer or further away from each other along the second guide rod 15 due to the opposite thread direction, thereby synchronizing or separating synchronously. Each sliding plate 16 is provided with a clamping assembly 17 for directly contacting and clamping the side wall of the workpiece.

[0020] The clamping assembly 17 includes a mounting groove 18, a sliding groove 19, a sliding rod 20, a limiting plate 21, a spring 22, a pressure plate 23, and an electric push rod 24. The mounting groove 18 is formed on the sliding plate 16. Several sliding grooves 19 are formed at the bottom of the mounting groove 18. A sliding rod 20 is slidably connected in each sliding groove 19. The sliding rod 20 can slide in the sliding groove 19. Limiting plates 21 are fixedly set at both ends of each sliding rod 20. A spring 22 is set between the sliding plate 16 and the limiting plate 21. The spring 22 is sleeved on the sliding rod 20. The pressure plate 23 is slidably connected in the mounting groove 18 and is located above the sliding rod 20. The electric push rod 24 is installed on the top of the sliding plate 16. The bottom of the telescopic rod of the electric push rod 24 is fixedly connected to the pressure plate 23 and is used to drive the pressure plate 23 to move vertically up and down in the mounting groove 18.

[0021] After the workpiece is placed on the support head 8 on the top plate 3, the second motor 13 drives the two sliding plates 16 to move closer to each other until the sliding rod 20 contacts the side wall of the workpiece. The side wall of the workpiece may not be completely flat. Each sliding rod 20 will compress the spring 22 according to the local contour of the side wall of the workpiece to produce different extension lengths, forming a contour-following contact. Then, the electric push rod 24 is activated, pushing the pressure plate 23 to move downward. The bottom surface of the pressure plate 23 abuts against the top of each sliding rod 20. As the pressure plate 23 continues to press down, the pressure plate 23 presses each sliding rod 20 down simultaneously, thereby locking the sliding rod 20 in the current extension position. At this time, multiple sliding rods 20 together form a clamping surface that matches the contour of the side wall of the workpiece, firmly clamping the workpiece. Due to the use of multiple independent floating and lockable sliding rods 20, the clamping assembly 17 can adapt to the irregular shape of the side wall of the workpiece, achieving surface contact instead of point contact, significantly increasing the clamping area and avoiding the problem of damage to the workpiece surface due to excessive local pressure in traditional fixtures.

[0022] After clamping, the CNC machining center can perform cutting on the workpiece. After machining, the electric push rod 24 drives the pressure plate 23 to rise, and the slide rod 20 automatically resets under the elastic force of the spring 22. The second motor 13 reverses to make the two slide plates 16 move away from each other. At the same time, the first motor 9 of each support mechanism 5 reverses to make the support head 8 descend, so that the machined workpiece can be easily removed.

[0023] The CNC machining center clamping fixture provided by this invention achieves adaptive multi-point support for the bottom surface of the workpiece through multiple independently controlled support mechanisms 5, and adaptive contour clamping of the side wall of the workpiece through the clamping assembly 17 with multiple floating slide rods 20 in the clamping mechanism 6. The two work together and are suitable for clamping thin-walled parts, irregular-shaped parts and other easily deformable workpieces, which can effectively reduce clamping stress and improve machining accuracy and yield.

[0024] All standard parts used in this invention can be purchased from the market. Each component in this invention can be customized according to the description and drawings. The specific connection methods of each component adopt conventional methods such as bolts, rivets, and welding that are mature in the prior art. The machinery, parts, and equipment all adopt conventional models in the prior art. The control method is automatic control through a controller. The control circuit of the controller can be implemented by those skilled in the art through simple programming, which is common knowledge in the field. Furthermore, since this invention is mainly used to protect mechanical devices, this application document will not explain the control method and circuit connection in detail, and will not be described in detail here.

[0025] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A clamping fixture for a CNC machining center, comprising a base plate (1), characterized in that, Also includes: The top plate (3) has several evenly distributed through holes (4). Support rod (2), the bottom plate (1) is fixedly connected to the top plate (3) through the support rod (2); A support mechanism (5) is disposed within the through hole (4); A clamping mechanism (6) is provided on the base plate (1); The support mechanism (5) includes a fixed cylinder (7), a support head (8), a first drive unit, and a position switch (12). The fixed cylinder (7) is fixedly disposed in the through hole (4). The support head (8) is slidably connected in the fixed cylinder (7). The first drive unit is installed in the fixed cylinder (7) and is used to drive the support head (8) to rise and fall. The position switch (12) is disposed on the top of the support head (8) and is electrically connected to the first drive unit.

2. The CNC machining center clamping fixture according to claim 1, characterized in that, The clamping mechanism (6) includes: The second drive unit is fixedly installed on the top of the base plate (1); The second screw (14) is connected to the second drive unit and drives it to rotate. The second screw (14) has two threaded segments with opposite thread directions. The second guide rod (15) is fixedly mounted on the base plate (1) and parallel to the second screw (14); Two sliding plates (16) are respectively threaded to two threaded sections of the second screw (14), and both sliding plates (16) are slidably connected to the second guide rod (15); A clamping assembly (17) is provided on each of the slide plates (16).

3. The CNC machining center clamping fixture according to claim 1, characterized in that, The first drive unit includes a first motor (9), a first screw (10), and a first guide rod (11). The first motor (9) is installed inside the fixed cylinder (7). The first screw (10) is fixedly connected to the output shaft of the first motor (9) and threadedly connected to the support head (8). The first guide rod (11) is fixedly installed inside the fixed cylinder (7), and the support head (8) is slidably connected to the first guide rod (11).

4. The CNC machining center clamping fixture according to claim 2, characterized in that, The clamping assembly (17) includes: Mounting slot (18) is provided on the slide plate (16); Multiple sliding grooves (19) are provided at the bottom of the mounting groove (18), and a sliding rod (20) is slidably connected in each sliding groove (19); Limiting plates (21) are disposed at both ends of the slide rod (20); A spring (22) is disposed between the slide plate (16) and the limiting plate (21); The pressure plate (23) is slidably connected to the mounting groove (18); An electric actuator (24) is mounted on the slide plate (16). The bottom of the electric actuator (24) is fixedly connected to the pressure plate (23) and is used to drive the pressure plate (23) to press against the top of the slide bar (20).

5. The CNC machining center clamping fixture according to claim 1, characterized in that, The number of the support mechanisms (5) is multiple, and the multiple support mechanisms (5) are correspondingly arranged with the multiple through holes (4).

6. The CNC machining center clamping fixture according to claim 2, characterized in that, The second drive unit is a second motor (13), which is mounted on the base plate (1) and the output shaft of the second motor (13) is fixedly connected to the second screw (14).

7. The CNC machining center clamping fixture according to claim 4, characterized in that, The top of the slide bar (20) abuts against the bottom surface of the pressure plate (23).

8. The CNC machining center clamping fixture according to claim 4, characterized in that, The spring (22) is sleeved on the slide bar (20), and the two ends of the spring (22) abut against the slide plate (16) and the limiting plate (21) respectively.

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