Full-automatic lead screw auxiliary supporting mechanism of numerical control machine tool
The fully automatic ball screw auxiliary support mechanism driven by the hydraulic control system solves the deflection problem of CNC machine tool ball screws during long-stroke drive, achieving stable operation and improved accuracy, reducing noise and mechanical loss, and simplifying the assembly process.
Patent Information
- Application Number
- CN202520284727.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-21
- Publication Date
- 2026-02-03
- Estimated Expiration
- 2035-02-21
AI Technical Summary
Existing ball screw support mechanisms for CNC machine tools suffer from reduced operating speed and accuracy due to deflection during long-stroke drives, and also suffer from problems such as noise, impact damage, spring failure, and assembly difficulties.
The fully automatic ball screw auxiliary support mechanism, driven by a hydraulic control system, achieves automatic support of the ball screw through hydraulic cylinders and guide keys, avoiding mechanical impact. It uses feedback switches and rocker blocks to provide action commands and achieve automatic adjustment of support force.
It improves the smoothness and reliability of the machine tool's coordinate axis transmission, enhances operating speed and accuracy, reduces noise and mechanical loss, and simplifies the assembly process.
Smart Images
Figure CN223863300U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of CNC machine tool technology, specifically to a fully automatic lead screw auxiliary support mechanism for CNC machine tools. Background Technology
[0002] CNC machine tools are widely used processing equipment in the market, and ball screws are a common structural form for driving the coordinate axes of machine tools. Ball screws have particularly prominent structural advantages in short-stroke drives, but when used in long-stroke drives, due to the excessive length of the screw, it will experience significant deflection under its own weight, and this deflection is difficult to overcome. This problem greatly affects the operating speed and accuracy of the ball screw, and can even render it unusable. Therefore, to solve the problem of screw deflection, it is necessary to add an external mechanism to support the screw. Currently, existing structures for ball screw support include... Figure 7 and Figure 8 This structure uses a spring compression and extension method to apply external force to support the ball screw. The sliding bracket 26 applies upward thrust under the combined action of springs 28 and 29. The two rollers on the sliding bracket 26 support the ball screw. The magnitude of the spring force and the height of the support are achieved by changing the thickness of the adjusting shim 34. Bearings 24 are mounted on the side plates of the sliding bracket 26 via shafts 25. An angled pressure plate 30 is mounted on the nut seat. When the nut and nut seat reach this support position, the pressure plate 30 first contacts the bearing 24, causing the bearing 24 to roll on the inclined surface of the pressure plate 30. Simultaneously, it applies downward pressure to the sliding bracket 26. The sliding bracket 26 moves downward along the oil-free bushing 27, compressing springs 28 and 29, preventing the nut and nut seat from impacting the ball screw support mechanism. When the nut and nut seat pass this support position, the bearing 24 rolls on the rear inclined surface of the pressure plate 30, and springs 28 and 29 apply upward pressure to the sliding bracket 26. The sliding bracket 26 moves upward along the oil-free bushing 27 until the roller supports the ball screw. This mechanism has the following disadvantages:
[0003] (1) The up-and-down movement of the support mechanism is a mechanical impact, which will generate a lot of noise;
[0004] (2) Prolonged impacts will damage or even cause failure of the components of this mechanism;
[0005] (3) The impact method cannot be applied to high-speed operating conditions;
[0006] (4) With prolonged use, the spring will gradually fail and will not be able to provide sufficient support force. Maintenance and repair will be difficult, leading to mechanism failure.
[0007] (5) Adjusting the thickness of the shim during assembly is very difficult, resulting in poor assembly processability.
[0008] This utility model is designed to solve the above problems, specifically a fully automatic lead screw auxiliary support mechanism for CNC machine tools. Utility Model Content
[0009] To address the shortcomings of existing technologies, this utility model provides a fully automatic ball screw auxiliary support mechanism for CNC machine tools, which can replace existing mechanisms, improve the automation level of CNC machine tools, and simplify and improve the form of ball screw auxiliary support mechanisms.
[0010] This device is fixed to the machine tool bed and is a fully automatic lead screw auxiliary support mechanism.
[0011] To achieve the above objectives, this utility model provides the following technical solution: a fully automatic ball screw auxiliary support mechanism for CNC machine tools, comprising a hydraulic control system, a hydraulic cylinder drive mechanism, an auxiliary support mechanism, a ball screw, a switch feedback mechanism, and a bearing support mechanism; the mechanism is fixed to the machine tool bed, and the auxiliary support mechanism is driven by a hydraulic cylinder to achieve up-and-down movement. The hydraulic cylinder is fixed to the machine tool bed via a fixed sleeve, and an oil-free bushing one and an oil-free bushing two are respectively installed on the upper and lower parts of the fixed sleeve. A sliding bracket is slidably connected to the fixed sleeve via a guide key, and a roller assembly that can rotate with the ball screw is installed on the top of the sliding bracket; the switch feedback mechanism includes a rocker block one and a rocker block two symmetrically arranged on both sides of the support mechanism, and a feedback switch assembly, used to trigger the hydraulic cylinder to avoid movement.
[0012] As a further embodiment of this utility model: the hydraulic control system includes an accumulator and pressure feedback switch one and pressure feedback switch two. The accumulator is connected to the oil inlet and oil return lines of the hydraulic cylinder, and pressure feedback switch one and pressure feedback switch two are respectively installed in the oil inlet and oil return lines of the hydraulic cylinder.
[0013] As a further embodiment of this utility model: the sliding bracket is rigidly connected to the hydraulic cylinder piston rod by screws, and a keyway hole is opened on the side wall of the sliding bracket, with the guide key embedded in the keyway hole and fixedly connected to the fixing sleeve.
[0014] As a further embodiment of this utility model: the roller assembly includes two sets of rollers symmetrically distributed on both sides of the center line of the ball screw, each roller having a bearing assembly installed inside, and pivotally connected to the mounting groove at the top of the sliding bracket via a shaft.
[0015] As a further embodiment of this utility model: a side plate is provided at the top slot of the sliding bracket for structural reinforcement, and the side plate is fixed to both ends of the slot by fasteners.
[0016] As a further embodiment of this utility model: a sealing ring is installed at the top of the fixed sleeve, and the sealing ring and the outer wall of the sliding bracket form a dynamic sealing structure.
[0017] As a further aspect of this utility model: the supporting force of the hydraulic cylinder is achieved by adjusting the pressure of the hydraulic system, and the pressure value is determined by adjusting the actual deflection of the ball screw.
[0018] As a further embodiment of this utility model: the first sway block and the second sway block are respectively set at the left and right travel limit positions of the worktable. When the feedback switch assembly contacts the first sway block, it triggers a downward movement command of the support mechanism, and when it contacts the second sway block, it triggers a reset command of the support mechanism.
[0019] As a further embodiment of this utility model: hydraulic pipeline channels are provided at corresponding positions of the bed, sliding bracket and fixed sleeve, and the hydraulic pipelines are connected to the hydraulic cylinder through the channels.
[0020] As a further embodiment of this utility model: a nut seat is fixed on the bottom surface of the worktable on the machine tool bed, the nut is embedded in the nut seat, and the outer dimension of the nut seat is larger than the diameter of the ball screw to form an avoidance triggering structure.
[0021] Compared with the prior art, this utility model has the following advantages: it is fixed on the machine tool bed, and the hydraulic cylinder is driven by the hydraulic system to run and drive the auxiliary support mechanism to move up and down to automatically complete the support of the ball screw, avoiding the self-deflection and deformation of the long stroke ball screw, improving the stability and reliability of the machine tool's coordinate axis transmission, and achieving the purpose of improving the machine tool's running speed and accuracy. Attached Figure Description
[0022] Figure 1 This is a front view of the overall external structure of this utility model;
[0023] Figure 2 This is a left view of the overall external structure of this utility model;
[0024] Figure 3 This is a schematic diagram of the hydraulic principle of this utility model;
[0025] Figure 4 This is a schematic diagram of the support screw state of this utility model;
[0026] Figure 5 This is a schematic diagram of the unsupported lead screw of this utility model;
[0027] Figure 6 This is a schematic diagram of the pipeline connection of this utility model;
[0028] Figure 7 This is a schematic diagram of the bearing support structure of this utility model;
[0029] Figure 8 This is the main view of the existing support structure;
[0030] Figure 9 This is a side view of the existing support structure.
[0031] In the diagram: 1. Worktable; 2. Bed; 3. Support mechanism; 4. Feedback switch assembly; 5. Rocker 1; 6. Rocker 2; 7. Hydraulic cylinder; 8. Accumulator; 9. Pressure switch 1; 10. Pressure switch 2; 11. Support bearing assembly; 12. Sliding bracket; 13. Sealing ring; 14. Oil-free bushing 1; 15. Oil-free bushing 2; 16. Ball screw; 17. Guide key; 18. Hydraulic cylinder pipe connector 1; 19. Hydraulic cylinder pipe connector 2; 20. Shaft 1; 21. Roller; 22. Sliding bracket side plate 1; 23. Sliding bracket side plate 2; 24. Bearing; 25. Shaft 2; 26. Sliding bracket; 27. Oil-free bushing 3; 28. Main spring; 29. Secondary spring; 30. Pressure plate; 31. Fixed sleeve; 32. Nut; 33. Nut seat; 34. Adjusting shim. Detailed Implementation
[0032] To further illustrate the technical means and effects adopted by this utility model in order to achieve the intended utility model purpose, the following detailed description of the specific implementation methods, structure, features and effects of this utility model is provided in conjunction with the accompanying drawings and preferred embodiments.
[0033] Please see Figure 1-9 This utility model provides a technical solution: a fully automatic ball screw auxiliary support mechanism for CNC machine tools includes a hydraulic control system, a hydraulic cylinder drive mechanism, an auxiliary support mechanism, a ball screw, a switch feedback mechanism, and a bearing support mechanism. This device is fixed to the machine tool bed 2 and effectively supports the machine tool ball screw 16, preventing intermediate deflection deformation caused by the ball screw's own weight. The device is driven by a hydraulic system, and the system principle is as follows... Figure 3 The hydraulic cylinder 7 has pressure feedback switches 9 and 10 in its inlet and return lines to ensure stable and accurate oil pressure. The hydraulic system also includes an accumulator 8 to ensure stable system pressure and enable rapid response and action of the hydraulic cylinder 7, guaranteeing the reliability of the entire mechanism. The auxiliary support mechanism is driven up and down by the hydraulic cylinder 7, which is installed in the middle of the mechanism. The pipeline connections are as follows... Figure 6Round holes are added at corresponding positions on the bed 2, sliding bracket 12, and fixed sleeve 31 to allow hydraulic lines to be connected to the hydraulic cylinder 7. The supporting force applied by the hydraulic cylinder 7 is determined by the pressure provided by the hydraulic system and can be adjusted according to actual conditions. During debugging, the final determination is made by measuring the deflection of the ball screw 16. The overall support mechanism 3 is fixed to the machine tool bed through the fixed sleeve 31. The hydraulic cylinder 7 and guide key 17 are fixed to the fixed sleeve 31. Oil-free bushing 14 and oil-free bushing 2 15 are installed on the upper and lower parts of the fixed sleeve 31, respectively. The sliding bracket 12 is connected to the hydraulic cylinder 7 by screws and is driven by the hydraulic cylinder 7 to move along the oil-free bushing 14 and The oil-free bushing 15 moves up and down. A keyway hole is opened on the sliding bracket 12, and a guide key 17 is inserted into the keyway hole to orient and limit the sliding bracket 12. To prevent dust and other impurities from entering the mechanism, a sealing ring 13 is installed at the top of the fixed sleeve 31. The top of the sliding bracket 12 is machined with grooves and holes for installing the support bearing assembly 11. To ensure the rigidity of the sliding bracket 12 after slotting, sliding bracket side plates 23 are installed at both ends of the groove for reinforcement. The mechanism consists of two sets of roller assemblies. The roller assembly includes a bearing assembly 11 and a roller 21. The bearing assembly 11 is installed in the roller 21 and is mounted in the groove of the sliding bracket 12 via a shaft 20. Figure 4 Two rollers are evenly distributed on both sides of the center of the ball screw 16. The rollers are pushed by the hydraulic cylinder 7 to effectively support the ball screw 16. When the ball screw 16 rotates, the rollers 21 rotate together with the ball screw 16 on the shaft 20 through the bearing assembly 11 to avoid wear on the ball screw 16.
[0034] like Figure 1 and Figure 2Nut seat 33 is fixed to the machine tool worktable 1, and nut 32 is fixed to nut seat 33. The movement of the worktable 1 is achieved by rotating the ball screw 16 to drive nut 32 and nut seat 33. Because the size of nut 32 and nut seat 33 is larger than that of ball screw 16, when the worktable 1, nut 32 and nut seat 33 move to the position of support mechanism 3, they will collide with support mechanism 3. At this time, support mechanism 3 needs to move down to avoid the collision. The downward movement of support mechanism 3 requires a command from the control system. Feedback switch assembly 4, rocker block 1 5 and rocker block 2 6 can provide feedback commands to the system. Rocker block 1 5 and rocker block 2 6 are arranged on the left and right sides of support mechanism 3. When the worktable moves from left to right, feedback switch assembly 4 moves to rocker block 1 5 to generate a feedback signal to the control system. The control system sends a command to the hydraulic system to drive hydraulic cylinder 7 to move support mechanism 3. When the support mechanism 3 moves downward to avoid the nut 32 and nut seat 33, and the nut 32 and nut seat 33 pass the position of the support mechanism 3 and the feedback switch assembly 4 moves onto the rocker block 6, a feedback signal is generated to the control system. The control system sends a command to the hydraulic system to drive the hydraulic cylinder 7 to move the support mechanism 3 upward to continue supporting the ball screw 16. When the worktable moves from right to left, the feedback switch assembly 4 moves onto the rocker block 6 to generate a feedback signal to the control system. The control system sends a command to the hydraulic system to drive the hydraulic cylinder 7 to move the support mechanism 3 downward to avoid the nut 32 and nut seat 33. When the nut 32 and nut seat 33 pass the position of the support mechanism 3 and the feedback switch assembly 4 moves onto the rocker block 5, a feedback signal is generated to the control system. The control system sends a command to the hydraulic system to drive the hydraulic cylinder 7 to move the support mechanism 3 upward to continue supporting the ball screw 16.
[0035] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any way. Although the present utility model has been disclosed above with reference to a preferred embodiment, it is not intended to limit the present utility model. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present utility model. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present utility model without departing from the scope of the present utility model shall still fall within the scope of the present utility model.
Claims
1. A fully automatic lead screw auxiliary support mechanism for CNC machine tools, characterized in that: The system includes a hydraulic control system, a hydraulic cylinder drive mechanism, an auxiliary support mechanism, a ball screw (16), a switch feedback mechanism, and a bearing support mechanism. The entire system is fixed to the machine tool bed (2). The auxiliary support mechanism is driven by a hydraulic cylinder (7) to achieve up and down movement. The hydraulic cylinder (7) is fixed to the bed (2) through a fixed sleeve (31). The upper and lower parts of the fixed sleeve (31) are respectively equipped with an oil-free bushing one (14) and an oil-free bushing two (15). The sliding bracket (12) is slidably connected to the fixed sleeve (31) through a guide key (17). The top of the sliding bracket (12) is equipped with a roller assembly that can rotate with the ball screw (16). The switch feedback mechanism includes a rocker block one (5), a rocker block two (6), and a feedback switch assembly (4) symmetrically arranged on both sides of the support mechanism, which are used to trigger the hydraulic cylinder (7) to avoid movement.
2. The fully automatic lead screw auxiliary support mechanism for CNC machine tools according to claim 1, characterized in that: The hydraulic control system includes an accumulator (8), a pressure feedback switch one (9), and a pressure feedback switch two (10). The accumulator (8) is connected to the oil inlet and return lines of the hydraulic cylinder (7). The pressure feedback switch one (9) and the pressure feedback switch two (10) are respectively located in the oil inlet and return lines of the hydraulic cylinder (7).
3. The fully automatic lead screw auxiliary support mechanism for CNC machine tools according to claim 1, characterized in that: The sliding bracket (12) is rigidly connected to the piston rod of the hydraulic cylinder (7) by screws. The side wall of the sliding bracket (12) is provided with a keyway hole, and the guide key (17) is embedded in the keyway hole and fixedly connected to the fixing sleeve (31).
4. The fully automatic lead screw auxiliary support mechanism for CNC machine tools according to claim 1, characterized in that: The roller assembly includes two sets of rollers (21) symmetrically distributed on both sides of the center line of the ball screw (16). Each roller (21) is equipped with a bearing assembly (11) and is pivotally connected to the mounting groove at the top of the sliding bracket (12) via a shaft (20).
5. The fully automatic lead screw auxiliary support mechanism for CNC machine tools according to claim 4, characterized in that: The sliding bracket (12) has a side plate (23) at the top slot for structural reinforcement, and the side plate (23) is fixed to both ends of the slot by fasteners.
6. The fully automatic lead screw auxiliary support mechanism for CNC machine tools according to claim 1, characterized in that: A sealing ring (13) is installed at the top of the fixed sleeve (31), and the sealing ring (13) and the outer wall of the sliding bracket (12) form a dynamic sealing structure.
7. The fully automatic lead screw auxiliary support mechanism for CNC machine tools according to claim 1, characterized in that: The supporting force of the hydraulic cylinder (7) is regulated by the hydraulic system pressure.
8. The fully automatic lead screw auxiliary support mechanism for CNC machine tools according to claim 1, characterized in that: The first sway block (5) and the second sway block (6) are respectively set at the left and right travel limit positions of the worktable (1). When the feedback switch assembly (4) contacts the first sway block (5), it triggers the support mechanism to move down, and when it contacts the second sway block (6), it triggers the support mechanism to reset.
9. The fully automatic lead screw auxiliary support mechanism for CNC machine tools according to claim 1, characterized in that: The bed (2), sliding bracket (12) and fixed sleeve (31) are provided with hydraulic pipeline channels at corresponding positions, and the hydraulic pipelines are connected to the hydraulic cylinder (7) through the channels.
10. The fully automatic lead screw auxiliary support mechanism for CNC machine tools according to claim 1, characterized in that: A nut seat (33) is fixed on the bottom surface of the worktable (1) on the machine tool bed (2). The nut (32) is embedded in the nut seat (33). The outer dimension of the nut seat (33) is larger than the diameter of the ball screw (16) to form an avoidance triggering structure.