A bridge type gantry machining center with gear and rack structure

Abstract

The utility model discloses a bridge -type gantry machining center of gear and rack structure, including bridge -type gantry frame structure, the bridge -type gantry frame structure includes crossbeam, left stand, right stand, be located crossbeam width direction and be provided with two guide rails of front and back, be installed on the guide rail and have the slide, the slide lower end is installed with the slide saddle, be located crossbeam left and right sides and be provided with drive mechanism respectively, drive mechanism bottom gear and rack meshing transmission connection, and it drives crossbeam and sets up reciprocating motion along the guide rail of left stand, right stand, the workbench is placed between left stand, right stand. The device adopts optimized gear and rack transmission structure, combines double -motor clearance, roller guide and cooling lead screw technology, improves the rigidity, precision and thermal stability of machine tool, satisfies high -precision, high -efficient processing demand.

Description

Technical Field

[0001] This utility model relates to a bridge-type gantry machining center with a gear and rack structure, belonging to the technical field of machining centers. Background Technology

[0002] Gantry machining centers, as high-precision and high-efficiency heavy-duty CNC machine tools, are widely used in aerospace, automotive manufacturing, mold processing and other fields. Traditional gantry machining centers usually adopt a moving column or fixed beam structure, but their dynamic performance, rigidity and thermal stability are often limited under large stroke and high load machining scenarios.

[0003] In existing technologies, the columns of moving-column gantry machining centers need to move frequently, leading to a decrease in overall structural rigidity, especially during long-stroke machining, which is prone to vibration and deformation. While fixed-beam gantry machining centers have a relatively stable structure, they are limited by the static characteristics of the crossbeam, making it difficult to achieve high-speed, high-precision, and large-scale machining. In addition, traditional ball screw drives are prone to affecting positioning accuracy during long-stroke motion due to thermal deformation and mechanical backlash, while single-sided drive gear and rack structures are prone to crossbeam torsion due to transmission asymmetry, further reducing machining quality.

[0004] To address the aforementioned issues, some improved gantry machining centers have adopted a bridge-type structure design to enhance the rigidity and stability of the crossbeam. However, existing bridge-type gantry machining centers still have the following shortcomings in their transmission systems: 1. Insufficient transmission accuracy: Single-sided gear and rack transmission is prone to backlash and torsion, which affects machining accuracy and repeatability.

[0005] 2. Unsatisfactory thermal deformation control: During long-stroke machining, the lead screw and gear rack system are prone to thermal errors due to frictional heat generation, which affects machining stability.

[0006] 3. Limited dynamic response: Traditional driving methods may cause vibration due to inertial impact during high-acceleration motion, affecting the surface processing quality.

[0007] Therefore, there is an urgent need for a new type of bridge-type gantry machining center that adopts an optimized gear and rack transmission structure, combined with dual-motor backlash elimination, roller guides and cooling screw technology, to improve the rigidity, accuracy and thermal stability of the machine tool and meet the needs of high-precision and high-efficiency machining. Utility Model Content

[0008] To address the problems existing in the prior art, this utility model provides a bridge-type gantry machining center with a gear and rack structure, thereby solving the aforementioned technical problems.

[0009] To achieve the above objectives, the technical solution adopted by this utility model is: a bridge-type gantry machining center with a gear and rack structure, comprising a bridge-type gantry frame structure; the bridge-type gantry frame structure includes a crossbeam, a left column, and a right column; two guide rails are arranged in the width direction of the crossbeam; a slide is installed on the guide rail; a slide block is installed at the lower end of the slide block; a drive mechanism is arranged on the left and right sides of the crossbeam respectively; the bottom gear of the drive mechanism is meshed with the rack and pinion, which drives the crossbeam to reciprocate along the guide rails arranged on the left and right columns; a worktable is placed between the left and right columns.

[0010] Furthermore, a nut cooling screw is provided on the crossbeam; a slide is connected to the nut cooling screw; the slide reciprocates along the nut cooling screw and the guide rail.

[0011] Furthermore, a left sliding plate and a right sliding plate are provided at the lower part of the left and right ends of the crossbeam; the bottom of the left sliding plate is connected to the guide rail at the upper end of the left column; the bottom of the right sliding plate is connected to the guide rail at the upper end of the right column.

[0012] Furthermore, the drive mechanism includes a servo motor, a servo reducer, and a gear connected to the bottom of the servo reducer.

[0013] Furthermore, the guide rail is a heavy-duty roller guide rail.

[0014] Furthermore, the drive mechanism is fixedly connected to the left and right slide plates via a mounting bracket, and two sets of them are arranged in parallel to form a dual drive mechanism.

[0015] Furthermore, the crossbeam is connected to the left and right sliding plates via fasteners; the left and right sliding plates move in the X direction on the left and right columns; the slide block moves in the Y direction on the crossbeam; and the ram moves in the Z direction on the slide block.

[0016] The beneficial effects of this utility model are: 1. High Rigidity: Utilizing a moving beam, fixed column gantry frame structure, with fixed columns and a fixed worktable, the main frame is constructed of high-strength cast iron or welded structure, ensuring the overall rigidity of the machine tool. The application of heavy-duty roller guides further enhances rigidity and load-bearing capacity.

[0017] 2. High precision: The X-axis adopts a gear and rack combination with a dual-motor backlash elimination structure on both sides, which effectively eliminates gear and rack transmission backlash, improves transmission accuracy and dynamic response, and ensures stable operation.

[0018] Excellent thermal stability: The crossbeam adopts a bridge-type gantry structure with a large cross-section and a large guide rail span, improving bending resistance and thermal stability. The beam, slide, and ram adopt a box-in-box structure with symmetrical structure, which is conducive to uniform heat distribution and reduces thermal deformation. The lead screw and nut cooling system effectively controls the heat source, improving machining accuracy and stability. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a schematic diagram of the drive mechanism structure of this utility model; Figure 3 This is a schematic diagram of the rack structure of this utility model.

[0020] In the diagram: 1. Bridge-type gantry frame structure; 11. Crossbeam; 111. Nut cooling screw; 12. Left column; 121. Left slide plate; 13. Right column; 131. Right slide plate; 14. Slide seat; 15. Slide block; 2. Worktable; 3. Rack; 4. Guide rail; 5. Drive mechanism; 51. Servo motor; 52. Servo reducer. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. However, it should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit its scope.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention.

[0023] like Figure 1 , Figure 2 and Figure 3 As shown, a bridge-type gantry machining center with a gear and rack structure includes a bridge-type gantry frame structure 1; the bridge-type gantry frame structure 1 includes a crossbeam 11, a left column 12, and a right column 13; two guide rails 4 are arranged in the width direction of the crossbeam 11; a slide block 14 is installed on the guide rail 4; a slide block 15 is installed at the lower end of the slide block 14; a drive mechanism 5 is arranged on the left and right sides of the crossbeam 11 respectively; the bottom gear of the drive mechanism 5 is meshed with the rack 3 for transmission, which drives the crossbeam 11 to reciprocate along the guide rails 4 arranged in the left column 12 and the right column 13; a worktable 2 is placed between the left column 12 and the right column 13.

[0024] In this preferred embodiment, a nut cooling screw 111 is provided on the crossbeam 11; a slide block 14 is connected to the nut cooling screw 111; the slide block 14 reciprocates along the nut cooling screw 111 and the guide rail 4.

[0025] In this preferred embodiment, a left sliding plate 121 and a right sliding plate 131 are provided at the lower part of the left and right ends of the crossbeam 11; the bottom of the left sliding plate 121 is connected to the guide rail 4 at the upper end of the left column 12; the bottom of the right sliding plate 131 is connected to the guide rail 4 at the upper end of the right column 13.

[0026] In this preferred embodiment, the drive mechanism 5 includes a servo motor 51, a servo reducer 52, and a gear connected to the bottom of the servo reducer 52.

[0027] In this preferred embodiment, guide rail 4 is a heavy-duty roller guide rail.

[0028] In this preferred embodiment, the drive mechanism 5 is fixedly connected to the side ends of the left slide plate 121 and the right slide plate 131 via a mounting bracket, and two sets of them are arranged in parallel to form a dual drive mechanism.

[0029] In this preferred embodiment, the crossbeam 11 is connected to the left sliding plate 121 and the right sliding plate 131 by a fixing member; the left sliding plate 121 and the right sliding plate 131 move in the X direction on the left column 12 and the right column 13; the slide block 14 moves in the Y direction on the crossbeam 11; and the slide bolster 15 moves in the Z direction on the slide block 14.

[0030] The working principle of this device is as follows: X-axis motion: The servo motor drives a rack and pinion gear via a high-precision reducer, which in turn moves the slide along the guide rail on the column, achieving motion in the X-axis direction. The dual-motor backlash-free structure ensures the accuracy and stability of the transmission.

[0031] Y-axis motion: A servo motor drives a slide to move left and right along the guide rail on the crossbeam via a large-diameter ground leadscrew nut, achieving movement in the Y-axis direction. A cooling system controls the temperature of the leadscrew nut to reduce thermal deformation.

[0032] Z-axis motion: The servo motor drives the slide block to move up and down along the guide rail on the slide block through a large-diameter ground lead screw nut, thus realizing the motion in the Z-axis direction.

[0033] Overall control: The CNC system controls the movement of each axis to achieve complex machining trajectories. A high-rigidity structure, high-precision transmission, and a robust thermal management system ensure machining accuracy and stability.

[0034] Box-within-box structure: The crossbeam, slide, and ram constitute the box-within-box structure, forming a good force transmission path and improving overall rigidity; at the same time, the symmetrical structure helps to distribute heat evenly, reduce thermal deformation, and further improve the machining accuracy of the machine tool.

[0035] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions or improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A bridge-type gantry machining center with a gear and rack structure, characterized in that, The structure includes a bridge-type gantry frame structure (1); the bridge-type gantry frame structure (1) includes a crossbeam (11), a left column (12), and a right column (13); two guide rails (4) are provided in the width direction of the crossbeam (11); a slide (14) is installed on the guide rail (4); a slide block (15) is installed at the lower end of the slide block (14); a drive mechanism (5) is provided on the left and right sides of the crossbeam (11); the bottom gear of the drive mechanism (5) is meshed with the rack (3) and drives the crossbeam (11) to reciprocate along the guide rails (4) provided on the left column (12) and the right column (13); a workbench (2) is placed between the left column (12) and the right column (13).

2. The bridge-type gantry machining center with a gear and rack structure according to claim 1, characterized in that, A nut cooling screw (111) is provided on the crossbeam (11); a slide (14) is connected to the nut cooling screw (111); the slide (14) reciprocates along the nut cooling screw (111) and the guide rail (4).

3. A bridge-type gantry machining center with a gear and rack structure according to claim 1, characterized in that, The lower part of the left and right ends of the crossbeam (11) is provided with a left sliding plate (121) and a right sliding plate (131); the bottom of the left sliding plate (121) is connected to the guide rail (4) at the upper end of the left column (12); the bottom of the right sliding plate (131) is connected to the guide rail (4) at the upper end of the right column (13).

4. A bridge-type gantry machining center with a gear and rack structure according to claim 1, characterized in that, The drive mechanism (5) includes a servo motor (51), a servo reducer (52), and a gear connected to the bottom of the servo reducer (52).

5. A bridge-type gantry machining center with a gear and rack structure according to claim 1, characterized in that, The guide rail (4) is a heavy-duty roller guide rail.

6. A bridge-type gantry machining center with a gear and rack structure according to claim 1, characterized in that, The drive mechanism (5) is fixedly connected to the left slide plate (121) and the right slide plate (131) via a mounting bracket, and two sets of them are arranged in parallel to form a dual drive mechanism.

7. A bridge-type gantry machining center with a gear and rack structure according to claim 1, characterized in that, The crossbeam (11) is connected to the left slide plate (121) and the right slide plate (131) by a fastener; the left slide plate (121) and the right slide plate (131) move in the X direction on the left column (12) and the right column (13); the slide block (14) moves in the Y direction on the crossbeam (11); the slide ram (15) moves in the Z direction on the slide block (14).

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