A frame-in-frame crossbeam assembly having a fine adjustment mechanism

Abstract

The present application relates to the field of five-axis machining center, and particularly discloses a frame-in-frame beam assembly with fine adjustment mechanism, which is used for fine adjustment of a beam bearing a main shaft and side legs bearing the beam, the beam comprises a rectangle frame composed of a long plate and a connecting frame, fine adjustment mechanisms are symmetrically arranged on the long plate, and each fine adjustment mechanism comprises a first tension rod, an upper supporting plate and a lower supporting plate arranged on the long plate. When the beam has precision error due to self weight and load, firstly, straightness of the beam is detected by using a straightness gauge, and the bending error of the beam is recorded; then, a support is built below the center line of the beam, a micrometer is installed on the support, a sliding block is arranged on the beam and moved to the middle part, a needle of the micrometer is pointed on the sliding block, then a first tension nut is rotated, and the first tension rod pulls the upper supporting plate and the lower supporting plate, so as to compensate the bent beam, pull up the bent beam, and restore the precision of the machine tool.

Description

A frame-to-frame beam assembly with a fine-tuning mechanism Technical Field

[0001] This invention relates to five-axis machining center technology, specifically a frame-beam assembly with a fine-tuning mechanism. Background Technology

[0002] As is commonly known, bridge-type gantry five-axis machining centers employ a crossbeam-moving structural design. The crossbeam, as the main moving component, possesses excellent dynamic performance to achieve rapid and stable machine tool operation, supporting the movement of the rotating spindle and exhibiting high precision, making it suitable for high-precision machining applications such as aerospace equipment.

[0003] For example, the invention patent with application publication number CN117324971A, application publication date January 2, 2024, entitled "A Fully Symmetrical Box-in-Box Crossbeam Moving Gantry Frame Structure," includes a bed base, left column, right column, Z-axis drag structure, mounting crossbeam, Y-axis drag structure, oil storage structure, lubrication structure, and mounting structure. The spindle box, mounting crossbeam, and bed base are completely symmetrical in the X direction. The Z-axis drag structure drives the spindle box to move, avoiding the uncertainty of the thermal expansion direction of the connecting spindle and improving the machining accuracy and stability of the machine tool. The Z-axis drag structure drives the mounting crossbeam to move, which can effectively reduce the spindle box overhang and avoid the problem of poor rigidity caused by the long overhang of the spindle box. The oil storage structure stores and adds lubricating oil, and the lubrication structure adds lubricating oil to the Y-axis slider and Y-axis guide rail, reducing the friction between the Y-axis slider and Y-axis guide rail and improving the service life of the Y-axis slider.

[0004] The shortcoming of the existing technology is that, during the machining process, the crossbeam, as the main moving part, must be able to bear the weight of itself and key components such as the slide. However, after production assembly or after the machine tool has been used for a period of time, the crossbeam may bend due to stress and the weight of the parts. In particular, the deformation is more obvious at the center of the crossbeam. When performing large-size machining along the crossbeam, it is easy to cause errors in the Z-axis direction of the spindle. Summary of the Invention

[0005] The purpose of this invention is to provide a frame-to-frame beam assembly with a fine-tuning mechanism to address the aforementioned shortcomings in the prior art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a frame-to-frame beam assembly with a fine-tuning mechanism, which is used to fine-tune the beam supporting the main shaft and the side legs supporting the beam. The beam includes a rectangular frame composed of a long plate and a connecting frame. A fine-tuning mechanism is symmetrically arranged on the long plate. The fine-tuning mechanism includes a first tension rod, an upper support plate, and a lower support plate disposed on the long plate. The two ends of the first tension rod are threadedly connected to a first tension nut that abuts against the two support plates. Any one or both of the first tension nuts can be rotated and moved to restore the center of the long plate to its original bending state.

[0007] As a further description of the above technical solution: the middle section of the long plate is provided with an I-shaped rib, and the upper support plate and the lower support plate are respectively provided on both sides of the I-shaped rib.

[0008] As a further description of the above technical solution: a central support plate is symmetrically arranged on the upper part of the long plate, and the two central support plates and the I-shaped rib plate form a triangle.

[0009] As a further description of the above technical solution: a second tension rod for tensioning is provided between the central support plate and the upper support plate to limit the downward deformation of the center of the long plate.

[0010] As a further description of the above technical solution: an auxiliary connecting frame is provided on the connecting frame, and the auxiliary connecting frame extends into and is fixed within the long plate.

[0011] As a further description of the above technical solution: the auxiliary connecting frame is provided with an extension rod, the upper support plate is provided with an inclined surface, and one side of the extension rod is attached to the inclined surface to restrict the connecting frame from being attached to the long plate.

[0012] As a further description of the above technical solution: the extension rod is provided with a waist groove, the connecting frame is provided with a fixing rod extending into the waist groove, and the fixing rod is threadedly connected with a second tension nut that restricts the other side of the extension rod.

[0013] As a further description of the above technical solution: it also includes a force equalization component, which includes an adjusting screw threadedly connected in the vertical direction within the connecting frame, and a bracket rotatably connected to the adjusting screw that slides along the side leg.

[0014] As a further description of the above technical solution: a plurality of rollers are rotatably connected to the bracket, and sealing blocks are engaged at both ends of the bracket, the sealing blocks restricting the plurality of rollers.

[0015] As a further description of the above technical solution: a spacer frame is provided inside the connecting frame, and I-shaped ribs are provided at both ends of the spacer frame. An inner threaded sleeve that is threadedly connected to the adjusting screw is provided inside the spacer frame.

[0016] In the above technical solution, the crossbeam assembly with a fine-tuning mechanism provided by the present invention has the following beneficial effects: when an accuracy error occurs, the straightness of the crossbeam is first detected by a straightness tester, and the bending error of the crossbeam is recorded. Then, a support is built below the center line of the crossbeam, a dial indicator is installed on the support, a slider is slidably set on the crossbeam, and the slider is moved to the middle. The dial indicator needle is pointed to the slider, and then the first tension nut is rotated to pull the upper support plate and the lower support plate with the first tension rod, thereby compensating for the bent crossbeam, pulling up the bent crossbeam, and restoring the accuracy of the machine tool. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0018] Figure 1 is a schematic diagram of the overall structure provided in an embodiment of the present invention;

[0019] Figure 2 is a side view of the crossbeam plate provided in an embodiment of the present invention;

[0020] Figure 3 is an exploded view of the fine-tuning mechanism structure provided in an embodiment of the present invention;

[0021] Figure 4 is a structural explosion diagram of the force equalization component provided in an embodiment of the present invention;

[0022] Figure 5 is an enlarged view of point A in Figure 4;

[0023] Figure 6 is a schematic cross-sectional view of the force equalization component structure provided in an embodiment of the present invention;

[0024] Figure 7 is an enlarged view of point B in Figure 6;

[0025] Figure 8 is an exploded view of the beam structure provided in an embodiment of the present invention;

[0026] Figure 9 is a schematic cross-sectional view of the beam structure provided in an embodiment of the present invention;

[0027] Figure 10 is an enlarged view of point C in Figure 9;

[0028] Figure 11 is a cross-sectional schematic diagram of the auxiliary connecting frame structure provided in an embodiment of the present invention;

[0029] Figure 12 is a schematic diagram of the cross-section of the beam structure provided in an embodiment of the present invention.

[0030] Explanation of reference numerals in the attached figures:

[0031] 1. Crossbeam; 10. I-beam rib; 2. Connecting frame; 21. Auxiliary connecting frame; 211. Extension rod; 212. Waist groove; 22. Spacer frame; 23. Side cover plate; 231. Opening; 3. Side leg; 31. Guide rail; 4. Fine adjustment mechanism; 40. First tension nut; 41. First tension rod; 401. Retention ring; 42. Upper support plate; 43. Lower support plate; 421. Inclined surface; 5. Force equalizing component; 51. Intermediate frame; 52. Inner threaded sleeve; 53. Adjusting screw; 54. Bracket; 541. Slide groove; 55. Roller; 551. Sealing block; 60. Second tension nut; 61. Second tension rod; 62. Central support plate; 63. Adhesive block. Detailed Implementation

[0032] To enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0033] Please refer to Figures 1-12. This embodiment of the invention provides a technical solution: a frame-to-frame crossbeam assembly with a fine-tuning mechanism, including a crossbeam 1 and side legs 3. A main shaft is mounted on a slide block, which is mounted on a saddle. The saddle is slidably connected to the crossbeam 1. The crossbeam 1 needs to support the saddle, slide block, and main shaft. There are two side legs 3, symmetrically arranged. Guide rails 31 are provided on the side legs 3. The crossbeam 1 is slidably connected to the guide rails 31 on the side legs 3, enabling movement in the X-axis direction. As shown in Figure 3, the crossbeam 1 includes a long plate and a connecting frame. The rectangular frame consists of two sections. Multiple ribs are installed within the long section, providing support and reducing the weight of the crossbeam 1, facilitating motor drive. A fine-tuning mechanism 4 is symmetrically arranged on the long section. The fine-tuning mechanism 4 includes an upper support plate 42 and a lower support plate 43, both mounted on the long section. Referring to Figure 9, the upper support plate 42 is located in the upper section of the long section, and the lower support plate 43 is located in the lower section, diagonally spanning the long section. A first tension rod 41 is positioned between the upper support plate 42 and the lower support plate 43. The first tension rod 41 has threaded portions at both ends, from which extend an upper support plate 42 and a lower support plate 43, respectively. First tension nuts 40 are threaded onto the threaded portions, and the two first tension nuts 40 abut against the upper support plate 42 and the lower support plate 43, respectively. The two first tension rods 41 form an inverted triangle. When the crossbeam 1 experiences accuracy errors due to its own weight and load, a straightness tester is first used to check the straightness of the crossbeam 1, and the bending error of the crossbeam 1 is recorded. Then, a support frame is erected below the centerline of the crossbeam 1. A dial indicator is installed on the frame, and a slider is slidably set on the crossbeam 1. The slider is moved to the middle, and the pointer of the dial indicator is pointed to the slider. Then, the first tension nut 40 is rotated, so that the first tension rod 41 pulls the upper support plate 42 and the lower support plate 43, thereby compensating for the bending of the crossbeam 1, pulling up the bending crossbeam 1, and restoring the accuracy of the machine tool. Depending on the error, one or two of the first tension nuts 40 can be rotated. The first tension rod 41 facing the lower support plate 43 can be replaced by a retaining ring 401 instead of the first tension nut 40.

[0034] In another embodiment of the present invention, as shown in Figures 2 and 12, an I-shaped rib plate 10 is provided in the middle section of the long plate. The load-bearing structure of the crossbeam 1 is a two-point simply supported beam. The self-weight and the cutting force during processing are the main reasons for the bending deformation of the crossbeam 1 in the frame. The conventional internal cross-shaped rib plate structure is replaced with the I-shaped rib plate 10 structure. Finite element analysis shows that with the cross-shaped rib arrangement, the bending deformation is 0.0109mm, which meets the requirements; with the I-shaped rib arrangement, the bending deformation is 0.0115mm, which also meets the requirements. The I-shaped rib arrangement is stronger and simpler in structure. While reducing the weight, it is also easier to install the fine adjustment mechanism 4. The part that needs to be drilled for the first tension rod 41 to pass through is smaller, which is suitable for the fine adjustment mechanism 4. As shown in Figure 9, the upper support plate 42 and the lower support plate 43 are respectively provided on both sides of the I-shaped rib plate 10, spanning the length of the crossbeam 1, to ensure that the bending of the crossbeam 1 can be compensated.

[0035] In another embodiment of the present invention, as shown in FIG2, a central support plate 62 is symmetrically arranged on the upper part of the long plate (with the I-shaped rib 10 as the dividing line, the I-shaped rib 10 as the middle section, the upper part as the upper section, and the lower part as the lower section). The central support plate 62 and the I-shaped rib 10 form a triangle to increase the support capacity of the upper section and alleviate the deformation of the central part of the crossbeam 1 (the deformation is mainly the downward bending deformation).

[0036] Preferably, a second tension rod 61 is provided between the central support plate 62 and the upper support plate 42. A fitting block 63 is rotatably connected to one end of the second tension rod 61 facing the central support plate 62. The fitting block 63 has a fitting surface that adheres to the central support plate 62 under stress. A second tension nut 60 is threadedly connected to one end of the second tension rod 61 facing the upper support plate 42. After the first tension rod 41 has been fine-tuned and corrected, the second tension nut 60 is rotated to apply a tensile force to the central support plate 62. This restricts the downward deformation of the long plate's center, using the tensile force to counteract its own weight and the load, thus alleviating bending.

[0037] In another embodiment of the present invention, as shown in FIG8, side shields 23 are provided on both sides of the long plate, and an auxiliary connecting frame 21 is fixedly provided on the connecting frame 2 by screws. The auxiliary connecting frame 21 extends into the long plate and is fixed. The side shields 23 have openings 231 corresponding to the auxiliary connecting frame 21. The auxiliary connecting frame 21 fits against the ribs in the long plate and is fixed by means of fasteners (the fasteners can be screws). The way in which the auxiliary connecting frame 21 extends into the long plate makes the connection between the long plate and the connecting frame 2 tighter and can transmit vibration.

[0038] Preferably, the auxiliary connecting frame 21 is provided with an extension rod 211, the opening 231 corresponds to the extension rod 211, the upper support plate 42 is provided with an inclined surface 421, one side of the extension rod 211 is angled to the inclined surface 421, and the lower part of the inclined surface 421 is far away from the connecting frame 2. The extension rod 211 is provided with a waist groove 212, and the connecting frame 2 is provided with a fixing rod extending into the waist groove 212. The fixing rod is threaded with a second tension nut 60 that restricts the other side of the extension rod 211. When the second tension nut 60 presses against the extension rod 211 along the fixing rod, it will bring the extension rod 211 closer to the lower part of the inclined surface 421, thereby restricting the connecting frame 2 from adhering to the long plate, tightening the connecting frame 2 and the long plate, and increasing the tightness of the connection.

[0039] Preferably, as shown in Figures 10 and 11, the fixing rod can be the second tension rod 61. After the first tension rod 41 has been finely adjusted and corrected, rotating the second tension nut 60 can increase the supporting force and tighten the connecting frame 2 and the long plate.

[0040] In another embodiment of the present invention, as shown in Figures 5, 7, and 8, a force-equalizing component 5 is further included. This component includes an adjusting screw 53 threaded vertically into the connecting frame 2. A spacer frame 22 is provided within the connecting frame 2, and an inner threaded sleeve 52 is fixedly connected within the spacer frame 22. The adjusting screw 53 is threaded onto the inner threaded sleeve 52. A bracket 54, which slides along the side leg 3, is rotatably connected to the adjusting screw 53. The crossbeam 1 is mounted on the guide rail 31 of the side leg 3. The guide rail 31 is prone to damage under prolonged stress, requiring the crossbeam 1 to be lifted for replacement. However, by rotating the adjusting screw 53, the bracket 54 is brought into contact with the side leg 3, distributing the pressure on the guide rail 31 and extending the replacement time of the guide rail 31. An intermediate frame 51 is provided between the connecting frame 2 and the side leg 3.

[0041] Furthermore, the bracket 54 is provided with a sliding groove 541, and several rollers 55 roll along the sliding groove 541. The two ends of the bracket 54 are locked with sealing blocks 551 for easy replacement. Rotating the adjusting screw 53 lifts the bracket 54. At this time, the sealing blocks 551 can be removed to replace the damaged rollers 55 (because the pressure of the adjusting screw 53 is greater, it is more likely to be damaged). Then, the adjusting screw 53 is rotated again, and the rollers 55 press against the side legs 3 to share the burden of the guide rail 31 for support.

[0042] Preferably, a spacer frame 22 is provided inside the connecting frame 2, and I-shaped ribs 10 are provided at both ends of the spacer frame 22, which provide a certain support capacity.

[0043] During maintenance of the crossbeam 1, firstly, rotate the adjusting screw 53 to lift the bracket 54, disassemble the sealing block 551, replace the damaged roller 55, and then use a straightness tester to check the straightness of the crossbeam 1 and record the bending error of the crossbeam 1. Next, build a support below the center line of the crossbeam 1, install a dial indicator on the support, slide a slider on the crossbeam 1, and move the slider to the middle, pointing the dial indicator needle onto the slider. Then, rotate the first tension nut 40 to pull the first tension rod 41. Pull up the upper support plate 42 and the lower support plate 43 to compensate for the bent crossbeam 1, pull up the bent crossbeam 1, then rotate the second tension nut 60 to apply a pulling force to the center support plate 62, which restricts the downward deformation of the center of the long plate, and at the same time moves the extension rod 211 closer to the lower position of the inclined plane 421, thereby restricting the connecting frame 2 from adhering to the long plate, tightening the connecting frame 2 and the long plate, making the connection tighter, and finally rotate the adjusting screw 53 again to lower the bracket 54, with the roller 55 pressing against the side leg 3 to share the burden of the guide rail 31 for support.

[0044] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A frame-to-frame beam assembly with a fine-tuning mechanism for fine-tuning the beam (1) supporting the main shaft and the side legs (3) supporting the beam (1), characterized in that, The crossbeam (1) includes a rectangular frame composed of a long plate and a connecting frame (2). A fine-tuning mechanism (4) is symmetrically arranged on the long plate. The fine-tuning mechanism (4) includes a first tension rod (41), an upper support plate (42), and a lower support plate (43) arranged on the long plate. The two ends of the first tension rod (41) are threadedly connected to the two support plates. The rotation and movement of any one or both of the first tension nuts (40) causes the center of the long plate to bend back. The crossbeam (1) also includes a force equalizing component (5), which includes a component threadedly connected to the connecting frame (2) in the vertical direction. The adjusting screw (53) is rotatably connected to the adjusting screw (53) and a bracket (54) that slides along the side leg (3); a plurality of rollers (55) are rotatably connected to the bracket (54), and a sealing block (551) is snapped into both ends of the bracket (54), the sealing block (551) restricting the plurality of rollers (55); a spacer frame (22) is provided in the connecting frame (2), and an I-shaped rib plate (10) is provided at both ends of the spacer frame (22), and an inner thread sleeve (52) that is threadedly connected to the adjusting screw (53) is provided in the spacer frame (22).

2. A frame-to-frame beam assembly with a fine-tuning mechanism according to claim 1, characterized in that, The middle section of the long plate is provided with an I-shaped rib (10), and the upper support plate (42) and the lower support plate (43) are respectively provided on both sides of the I-shaped rib (10).

3. A frame-to-frame beam assembly with a fine-tuning mechanism according to claim 2, characterized in that, The upper part of the long plate is symmetrically provided with a central support plate (62), and the two central support plates (62) and the I-shaped rib plate (10) form a triangle.

4. A frame-to-frame beam assembly with a fine-tuning mechanism according to claim 3, characterized in that, A second tension rod (61) for tensioning is provided between the central support plate (62) and the upper support plate (42) to limit the downward deformation of the center of the long plate.

5. A frame-to-frame beam assembly with a fine-tuning mechanism according to claim 1, characterized in that, An auxiliary connecting frame (21) is provided on the connecting frame (2), and the auxiliary connecting frame (21) extends into the long plate and is fixed.

6. A frame-to-frame beam assembly with a fine-tuning mechanism according to claim 5, characterized in that, An extension rod (211) is provided on the auxiliary connecting frame (21), and an inclined surface (421) is provided on the upper support plate (42). One side of the extension rod (211) is attached to the inclined surface to restrict the connecting frame (2) from being attached to the long plate.

7. A frame-to-frame beam assembly with a fine-tuning mechanism according to claim 6, characterized in that, The extension rod (211) has a waist groove (212), and the connecting frame (2) is provided with a fixing rod extending into the waist groove (212). The fixing rod is threaded with a second tension nut (60) that restricts the other side of the extension rod (211).

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