Frictionless cylinder for high speed, high acceleration motion

Abstract

The application relates to the field of ultra-precision machining equipment, in particular to a frictionless cylinder for high-speed and high-acceleration movement, which comprises a cylinder main body and a piston assembly, the cylinder main body comprises a cylinder body and a piston rod guide sleeve at both ends of the cylinder body; the piston assembly is movably arranged in the cylinder main body and comprises a piston and piston rods connected to both ends of the piston. By setting the high-pressure cavity as the only gas cavity and adopting a fast independent exhaust passage, the exhaust resistance during high-speed and high-acceleration movement is weakened, so that the dynamic response speed and acceleration capacity of the cylinder are significantly improved, meanwhile, the exhaust of the high-pressure cavity to the low-pressure cavity is avoided, and the gas consumption of the cylinder is reduced; the static pressure bearing pair is directly supplied with gas by the high-pressure cavity, so that the bearing gas film pressure and the cavity pressure are automatically synchronized, the gas film disturbance caused by different pressure sources is eliminated, and the movement stability, rigidity and precision are greatly improved. The overall structure of the application is simplified, the cylinder is easier to produce, assemble and maintain, and the combination of high performance and low cost is realized.

Description

Technical Field

[0001] This invention relates to the field of ultra-precision machining equipment, and in particular to a frictionless cylinder for high-speed, high-acceleration motion. Background Technology

[0002] Frictionless cylinders are key functional components in ultra-precision machine tools. By incorporating throttling orifices and air grooves on the piston rod, guide sleeve, and piston, an air film is formed between the piston rod and guide sleeve, and between the piston and cylinder barrel, creating an air hydrostatic bearing pair. This achieves contactless sealing and frictionless motion. Compared to traditional cylinders, frictionless cylinders offer significant advantages in constant force output control and micro-pressure action control.

[0003] However, existing frictionless cylinders, whether single-acting or double-acting, rely on precision pressure regulating valves for exhaust during the high-pressure chamber compression phase. When the cylinder needs to move at a speed greater than 20 mm / s or an acceleration greater than 1G, the precision pressure regulating valve exhibits a significant throttling and deceleration effect during exhaust. The higher the operating speed and acceleration, the more pronounced this deceleration effect becomes. This severely restricts the ability of ultra-precision machine tools to achieve high-speed, high-acceleration motion on the vertical axis, greatly limiting the overall motion performance of the machine tool.

[0004] Furthermore, in existing frictionless cylinder structures, the gas in the high-pressure chamber easily disturbs the gas film of the air bearing. This not only reduces the stability of the gas film and the radial load capacity of the piston, but also increases the risk of cylinder "stalling" failure, thus affecting motion accuracy. To solve this problem, existing technologies typically employ complex structural designs to introduce the high-pressure chamber gas into the hydrostatic bearing pair, or use complex exhaust structures to isolate the high-pressure chamber of the cylinder from the hydrostatic bearing to avoid mutual interference, or use dual air supply with a one-way valve to achieve intake and exhaust functions. However, these solutions result in complex cylinder and piston structures, high manufacturing difficulty, poor stability, and difficult maintenance. Summary of the Invention

[0005] This invention provides a frictionless cylinder for high-speed, high-acceleration motion, which solves the defects of existing frictionless cylinders in high-speed, high-acceleration motion, such as decreased motion performance, unstable precision, and high risk of stalling, due to exhaust throttling effect and disturbance of the air film of the air bearing by the high-pressure chamber gas.

[0006] The present invention provides a frictionless cylinder for high-speed, high-acceleration motion, comprising a cylinder body and a piston assembly. The cylinder body includes a cylinder body and a first piston rod guide sleeve and a second piston rod guide sleeve respectively fixed at both ends of the cylinder body. The piston assembly is movably disposed within the cylinder body and includes a piston and a first piston rod and a second piston rod respectively connected to both ends of the piston.

[0007] The first piston rod is movably inserted through the first piston rod guide sleeve, forming a first gas static pressure bearing pair between the first piston rod and the first piston rod guide sleeve; the second piston rod is movably inserted through the second piston rod guide sleeve, forming a second gas static pressure bearing pair between the second piston rod and the second piston rod guide sleeve.

[0008] A high-pressure chamber is formed in the area between the first piston rod guide sleeve and the second piston rod guide sleeve, and an annular gap is formed between the piston and the inner wall of the cylinder.

[0009] The second piston rod guide sleeve is provided with an intake passage and at least one exhaust passage that communicate with the high-pressure chamber.

[0010] According to the present invention, a frictionless cylinder for high-speed, high-acceleration motion is provided in which the effective pressure-bearing area of ​​the end face of the piston facing the second piston rod guide sleeve is greater than the effective pressure-bearing area of ​​the end face of the piston facing the first piston rod guide sleeve, so that after gas is introduced into the high-pressure chamber, a pressure difference is formed between the two end faces of the piston, providing levitation force for the piston assembly.

[0011] According to the present invention, a frictionless cylinder for high-speed, high-acceleration motion is provided, wherein the first end of the second piston rod is connected to the piston via a ball joint structure.

[0012] According to the present invention, a frictionless cylinder for high-speed, high-acceleration motion is provided, wherein the ball hinge structure includes a ball head disposed at the first end of the second piston rod and a ball pin seat disposed on the piston end face, the ball head and the ball pin seat forming a spherical pair.

[0013] According to the present invention, a frictionless cylinder for high-speed, high-acceleration motion is provided, wherein a spherical bearing is installed at the second end of the second piston rod for connection with an external actuator.

[0014] According to the present invention, a frictionless cylinder for high-speed, high-acceleration motion is provided, wherein the first piston rod guide sleeve and the cylinder body, and the second piston rod guide sleeve and the cylinder body are sealed by a sealing element; both the first gas hydrostatic bearing pair and the second gas hydrostatic bearing pair are surface throttling type hydrostatic bearings.

[0015] According to the present invention, a frictionless cylinder for high-speed, high-acceleration motion is provided, wherein a plurality of axially extending throttling grooves are provided on the inner wall of the first piston rod guide sleeve and / or the second piston rod guide sleeve, and the plurality of throttling grooves are uniformly distributed circumferentially along the inner wall of the first piston rod guide sleeve and / or the second piston rod guide sleeve. The gas in the high-pressure chamber passes through the throttling grooves and enters the first gas static pressure bearing pair and / or the second gas static pressure bearing pair to form a gas film.

[0016] According to the present invention, a frictionless cylinder for high-speed, high-acceleration motion is provided, wherein the cross-sectional shape of the throttling groove is triangular, rectangular or trapezoidal.

[0017] According to the present invention, a frictionless cylinder for high-speed, high-acceleration motion is provided, wherein the air intake passage includes an air intake pipe connector disposed on the second piston rod guide sleeve and a cylinder air intake passage communicating with the air intake pipe connector, and the air intake pipe connector is used to connect an external precision pressure regulating valve.

[0018] According to the present invention, a frictionless cylinder for high-speed, high-acceleration motion is provided, wherein the exhaust passage includes an exhaust pipe connector disposed on the second piston rod guide sleeve and a cylinder exhaust flow channel communicating with the exhaust pipe connector, and the exhaust pipe connector is used to connect an external relief valve.

[0019] The frictionless cylinder for high-speed, high-acceleration motion provided by this invention supplies air to the high-pressure chamber through an intake passage located on the second piston rod guide sleeve. The high-pressure gas serves as both the driving medium and, simultaneously, directly supplies air to the first and second gas static pressure bearing pairs through a throttling structure on the inner wall of the guide sleeve, forming a stable gas film and achieving frictionless motion and contactless sealing of the piston assembly. When the piston moves, the gas in the high-pressure chamber can be quickly discharged through a precision pressure regulating valve, an independent exhaust passage, and a connected overflow valve. This invention significantly reduces exhaust resistance during high-speed, high-acceleration operation by designating the high-pressure chamber as the sole air chamber and employing a rapid, independent exhaust path. This substantially improves the cylinder's dynamic response speed and acceleration capability, while simultaneously preventing exhaust from the high-pressure chamber to the low-pressure chamber, thus reducing the cylinder's air consumption. The hydrostatic bearing pair is directly supplied with air from the high-pressure chamber, automatically synchronizing the bearing film pressure with the chamber pressure. This completely eliminates film disturbances caused by different pressure sources, greatly improving motion stability, stiffness, and precision, and reducing the risk of stalling. The overall structure of the frictionless cylinder for high-speed, high-acceleration motion is simplified, reducing the precision requirements for key components such as the cylinder body. This makes the cylinder easier to manufacture, assemble, and maintain, achieving a combination of high performance and low cost. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0021] Figure 1This is a three-dimensional structural schematic diagram of a frictionless cylinder for high-speed, high-acceleration motion provided by the present invention.

[0022] Figure 2 This is a cross-sectional structural schematic diagram of a frictionless cylinder for high-speed, high-acceleration motion provided by the present invention.

[0023] Figure 3 This is a schematic diagram of the working principle of the cylinder and hydrostatic bearing pair of the frictionless cylinder for high-speed, high-acceleration motion provided by the present invention.

[0024] Figure 4 This is a schematic diagram of cylinder buoyancy generation for a frictionless cylinder used in high-speed, high-acceleration motion, provided by the present invention.

[0025] Figure 5 This is a schematic diagram of the mating structure of the second piston rod guide sleeve and the second piston rod provided by the present invention.

[0026] Figure 6 This is a schematic diagram of the mating structure of the first piston rod guide sleeve and the first piston rod provided by the present invention.

[0027] Figure 7 yes Figure 6 A schematic diagram of the AA cross-section.

[0028] Figure 8 yes Figure 7 Enlarged view of the structure of part B.

[0029] Reference numerals in the attached drawings: 1. Cylinder block; 2. First piston rod guide sleeve; 3. Second piston rod guide sleeve; 4. Piston; 5. First piston rod; 6. Second piston rod; 7. First gas hydrostatic bearing pair; 8. Second gas hydrostatic bearing pair; 9. High-pressure chamber; 10. Annular clearance; 11. Ball head; 12. Ball pin seat; 13. Spherical plain bearing; 14. Throttling groove; 15. Intake pipe connector; 16. Cylinder intake air passage; 17. Exhaust pipe connector; 18. Cylinder exhaust air passage. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0031] The following is combined with Figures 1 to 8 The present invention describes the specific structure and working process of a frictionless cylinder for high-speed, high-acceleration motion.

[0032] One embodiment of the present invention provides a frictionless cylinder for high-speed, high-acceleration motion, combined with Figure 1 and Figure 2 As shown, the frictionless cylinder for high-speed, high-acceleration motion includes a cylinder body and a piston assembly. The cylinder body includes a cylinder body 1 and a first piston rod guide sleeve 2 and a second piston rod guide sleeve 3, which are respectively fixed to both ends of the cylinder body 1. The piston assembly is movably disposed in the cylinder body and includes a piston 4 and a first piston rod 5 and a second piston rod 6, which are respectively connected to both ends of the piston 4.

[0033] The first piston rod 5 movably passes through the first piston rod guide sleeve 2, forming a first gas static pressure bearing pair 7 between the first piston rod 5 and the first piston rod guide sleeve 2; the second piston rod 6 movably passes through the second piston rod guide sleeve 3, forming a second gas static pressure bearing pair 8 between the second piston rod 6 and the second piston rod guide sleeve 3. A high-pressure chamber 9 is formed in the area between the first piston rod guide sleeve 2 and the second piston rod guide sleeve 3. An annular gap 10 is formed between the piston 4 and the inner wall of the cylinder 1, making the high-pressure chamber 9 the only gas chamber within the frictionless cylinder. The second piston rod guide sleeve 3 is provided with an intake passage communicating with the high-pressure chamber 9 and at least one exhaust passage.

[0034] It is understood that this frictionless cylinder for high-speed, high-acceleration motion is a simplification and optimization of the traditional cylinder structure. The frictionless cylinder eliminates the complex hydrostatic bearing pair between the piston and the cylinder body, replacing it with two sets of gas hydrostatic bearing pairs (first gas hydrostatic bearing pair 7 and second gas hydrostatic bearing pair 8) formed by the first piston rod guide sleeve 2 and the second piston rod guide sleeve 3 located at the two ends of the cylinder body 1, and the first piston rod 5 and the second piston rod 6 that cooperate with them. The first gas hydrostatic bearing pair 7 and the second gas hydrostatic bearing pair 8 are fixed to the upper and lower ends of the cylinder body 1, respectively, eliminating the stiffness changes caused by piston movement in traditional frictionless cylinders. The area between these two bearing pairs constitutes a unified high-pressure chamber 9, and a significant annular gap 10 is designed between the piston 4 and the inner wall of the cylinder body 1, making the high-pressure chamber 9 the only gas chamber in the cylinder. This eliminates the gas disturbance and pressure balance problems caused by the coexistence of high-pressure and low-pressure chambers in traditional designs, while also preventing exhaust from the high-pressure chamber to the low-pressure chamber, thus reducing gas consumption.

[0035] When at work, see Figure 3As shown, an external air source supplies air to the high-pressure chamber 9 through an air inlet passage located on the second piston rod guide sleeve 3. The high-pressure gas serves as both the driving medium and, simultaneously, directly supplies air to the first gas static pressure bearing assembly 7 and the second gas static pressure bearing assembly 8 through a throttling structure on the inner wall of the guide sleeve, forming a stable gas film and achieving frictionless movement and contactless sealing of the piston assembly. When high-speed, high-acceleration movement is required, the gas in the high-pressure chamber 9 can be rapidly discharged simultaneously through a precision pressure regulating valve and an independent exhaust passage connected to it, effectively avoiding the throttling and deceleration effect caused by relying solely on the precision pressure regulating valve for exhaust in traditional structures.

[0036] It is important to understand that this frictionless cylinder for high-speed, high-acceleration motion, by designating the high-pressure chamber 9 as the sole air chamber and employing a rapid, independent exhaust path, significantly reduces exhaust resistance during high-speed, high-acceleration operation, thereby substantially improving the cylinder's dynamic response speed and acceleration capability. The hydrostatic bearing assembly is directly supplied with air from the high-pressure chamber 9, automatically synchronizing the bearing film pressure with the chamber pressure, completely eliminating film disturbances caused by different pressure sources, greatly improving motion stability, stiffness, and accuracy, and reducing the risk of "stuck" (or "locked up"). The overall structure of this frictionless cylinder for high-speed, high-acceleration motion is simplified, reducing the precision requirements for key components such as the cylinder body 1 and piston 4, making the cylinder easier to manufacture, assemble, and maintain, achieving a combination of high performance and low cost.

[0037] In some embodiments of the frictionless cylinder for high-speed, high-acceleration motion of the present invention, see [link to relevant documentation]. Figure 4 As shown, the effective pressure-bearing area of ​​the end face of piston 4 facing the second piston rod guide sleeve 3 is greater than the effective pressure-bearing area of ​​the end face of piston 4 facing the first piston rod guide sleeve 2, so that after gas is introduced into the high-pressure chamber 9, a pressure difference is formed between the two end faces of piston 4, providing levitation force for the piston assembly.

[0038] It is understood that in the structure of the frictionless cylinder for high-speed, high-acceleration motion in this embodiment, the piston assembly can achieve self-levitation. Specifically, see... Figure 4 As shown, the end face of piston 4 facing the second piston rod guide sleeve 3 (i.e., the lower end face) is a complete annular plane, while the end face facing the first piston rod guide sleeve 2 (i.e., the upper end face) is occupied by the piston rod cross section due to the through connection of the first piston rod 5. This makes the effective pressure-bearing area of ​​the lower end face of piston 4 a complete annular area, while the effective pressure-bearing area of ​​the upper end face is an annular area. The effective pressure-bearing area of ​​the lower end face is significantly larger than that of the upper end face. Therefore, under the same cavity air pressure, the total upward pressure acting on the lower end face of piston 4 will always be greater than the total downward pressure acting on the upper end face.

[0039] When high-pressure gas enters the high-pressure chamber 9 through the intake passage, it acts simultaneously on the upper and lower end faces of piston 4. Due to the aforementioned difference in effective pressure-bearing area, according to the principle of fluid pressure action (F=P×S), under the same pressure P, the end with a larger area S experiences a greater force. Therefore, piston 4 experiences a net upward force, i.e., a levitation force. This levitation force counteracts the weight of the piston assembly itself and the external load connected to it, while also reducing overall energy consumption to a certain extent.

[0040] In some embodiments of the frictionless cylinder for high-speed, high-acceleration motion of the present invention, see again Figure 2 As shown, the first end of the second piston rod 6 is connected to the piston 4 via a ball joint structure. In some specific examples, the ball joint structure includes a ball head 11 disposed at the first end of the second piston rod 6 and a ball pin seat 12 disposed on the end face of the piston 4, wherein the ball head 11 and the ball pin seat 12 form a spherical pair.

[0041] It is understood that the frictionless cylinder structure for high-speed, high-acceleration motion in this embodiment solves the alignment and off-center loading problems during motion by introducing a ball joint structure at the connection between the second piston rod 6 and the piston 4. Specifically, the ball joint structure includes a ball head 11 integrated into the first end of the second piston rod 6 and a ball pin seat 12 fixedly mounted on the corresponding end face of the piston 4. The ball head 11 is precisely constrained within the cavity of the ball pin seat 12, and the two together form a spherical pair capable of achieving multi-degree-of-freedom micro-rotation. The connection between the ball head 11 and the ball pin seat 12 is not a rigid fixed connection, but rather allows relative deflection between the second piston rod 6 and the piston 4 within a certain angular range.

[0042] During the operation of a frictionless cylinder, when slight misalignment or uneven stress occurs in the piston assembly due to machining errors, assembly errors, or external loads, the ball joint structure comes into play. At this time, a rigid connection may generate a large additional bending moment, leading to a decrease in the local clearance of the hydrostatic bearing pair between the piston rod and the guide sleeve, uneven distribution of the gas film pressure, and even metal-to-metal contact (i.e., "seal-off"). The structure of this embodiment, through the adaptive rotation of the ball joint 11, can absorb and compensate for these minor eccentricities and deflections, releasing potential bending stress. This ensures that the second gas hydrostatic bearing pair 8 between the second piston rod 6 and the second piston rod guide sleeve 3 is always in a state of uniform clearance and optimal gas film pressure distribution, significantly improving the cylinder's adaptability to errors, reducing the difficulty of machining and assembling precision parts, enhancing the cylinder's operational reliability and stability, and avoiding the risk of jamming.

[0043] Furthermore, a spherical plain bearing 13 is installed at the second end of the second piston rod 6 for connection with an external actuator. It is understood that in this embodiment, a spherical plain bearing is installed at the second end of the second piston rod 6 (i.e., the connection end with the external component). Specifically, as a common spatial connector, the outer ring of the spherical plain bearing is typically fixed to the mounting position at the end of the piston rod by threads or press fitting, while the inner ring has a connecting hole for hinged connection with an external actuator (such as a machine tool table, robotic arm, etc.) via a pin or other component. This allows the connection point to withstand not only radial loads but also a certain degree of axial loads, and permits angular deflection between the two connectors.

[0044] In the actual operation of the cylinder, mounting holes need to be designed on the second piston rod guide sleeve 3 of the frictionless cylinder to fix the cylinder to the machine tool. Even if the cylinder is rigidly fixed, the external actuator driven by it will inevitably produce slight trajectory deviations or deformation of the mounting base during high-speed or long-stroke movements. At this time, if a rigid connection is used, these errors will form additional bending moments and radial forces, which are directly transmitted to the piston rod, seriously threatening the stable operation of the gas hydrostatic bearing pair. The introduction of the spherical plain bearing in this embodiment can adaptively compensate for these angular deviations through the sliding or rolling contact between its inner and outer rings, converting the harmful bending moment into free deflection inside the spherical plain bearing. This ensures that the piston rod and its components are always in an ideal axial force state, greatly reducing the interference of external connection errors on the precision air bearing inside the cylinder, effectively protecting the integrity and stability of the gas film. This not only extends the service life of the cylinder but also reduces the stringent requirements for the installation accuracy of the entire motion system, improving the robustness of engineering applications.

[0045] In some embodiments of the frictionless cylinder for high-speed, high-acceleration motion of the present invention, the first piston rod guide sleeve 2 and the cylinder body 1, and the second piston rod guide sleeve 3 and the cylinder body 1 are sealed by a seal; the first gas static pressure bearing assembly 7 and the second gas static pressure bearing assembly 8 are both surface throttling type static pressure bearings.

[0046] It is understood that in the structure of the frictionless cylinder for high-speed, high-acceleration motion of the present invention, the sealing of the high-pressure chamber 9 and the air supply method of the hydrostatic bearing constitute the core of the system. In this embodiment, combined with Figure 2 and Figure 5 and combination Figure 2 and Figure 6As shown, sealing grooves and O-rings are respectively provided at the mating interfaces of the first piston rod guide sleeve 2, the second piston rod guide sleeve 3 and the cylinder body 1. These static seals reliably isolate the high-pressure chamber 9, ensuring the stable establishment of pressure within the chamber. Meanwhile, both the first gas static bearing assembly 7 and the second gas static bearing assembly 8 adopt a surface throttling design. Their throttling elements are not independent throttling orifices or pinhole throttlers, but rather throttling grooves 14 of a specific geometric shape directly machined onto the inner wall surface of the piston rod guide sleeve.

[0047] During implementation, when high-pressure gas enters the high-pressure chamber 9, part of the gas serves as the driving medium, while the other part directly enters the tiny gap between the piston rod and the guide sleeve through the throttling grooves 14 machined on the inner wall of the guide sleeve. As the gas flows through the throttling grooves, a pressure drop occurs, which then diffuses in the bearing gap and forms a uniform and stable gas film, simultaneously generating the static pressure bearing capacity that supports the piston rod. This integrated design, where the high-pressure chamber 9 directly supplies gas to the static pressure bearing, ensures that the bearing gas source and the driving gas source are of the same origin and pressure. This eliminates gas film pressure fluctuations and disturbances caused by pressure mismatches from multiple independent gas sources, improves the stiffness and motion stability of the static pressure bearing pair, ensures precise axial movement of the piston assembly, simplifies the gas path system, eliminates the need for complex pipelines and pressure regulating devices for separate gas supply to the bearing, and achieves a balance between low gas consumption and high motion precision.

[0048] Specifically, in some specific examples, see Figure 7 and Figure 8 As shown, multiple axially extending throttling grooves 14 are provided on the inner walls of the first piston rod guide sleeve 2 and / or the second piston rod guide sleeve 3. These throttling grooves 14 are evenly distributed circumferentially along the inner walls of the first piston rod guide sleeve 2 and / or the second piston rod guide sleeve 3. Gas in the high-pressure chamber 9 passes through the throttling grooves 14 and enters the first gas static pressure bearing assembly 7 and / or the second gas static pressure bearing assembly 8 to form a gas film. The cross-sectional shape of the throttling grooves 14 is triangular, rectangular, or trapezoidal.

[0049] Understandably, to achieve high performance and high reliability in hydrostatic bearings, the throttling structure in this example employs a precise surface design. Specifically, several slender throttling grooves 14 are machined axially on the inner cylindrical surfaces of the first piston rod guide sleeve 2 and the second piston rod guide sleeve 3. These throttling grooves 14 are evenly distributed in the circumferential direction of the guide sleeve's inner wall; for example, 36 or 72 grooves can be provided. This ensures that high-pressure gas can uniformly flow around the piston rod into the bearing clearance. Crucially, the cross-sectional shape of these throttling grooves 14 is designed with specific geometric shapes such as triangles, rectangles, or trapezoids, making the channels easy to machine and ensuring relatively high consistency. Their cross-sectional shape and dimensions directly determine the gas flow rate and throttling effect.

[0050] During cylinder operation, the gas in the high-pressure chamber 9, driven by pressure, simultaneously enters the circumferentially uniformly distributed throttling grooves 14. As the gas flows through the narrow cross-section of these grooves, its pressure energy is partially converted into kinetic energy due to the throttling effect, resulting in a pressure drop. Subsequently, this gas, throttled by the throttling grooves 14, enters the extremely small radial gap (typically a few micrometers to tens of micrometers) between the piston rod and the guide sleeve, where it rapidly diffuses and merges, forming a continuous, uniform, and symmetrically pressure-distributed annular gas film. This uniform gas film suspends the piston rod at the center of the guide sleeve, achieving contactless support. The circumferentially uniformly distributed throttling grooves 14 ensure that the supporting force on the piston rod is uniform and symmetrical, thus providing extremely high radial stiffness and operational accuracy. The specific groove cross-section provides stable and controllable throttling characteristics, ensuring the dynamic stability of the gas film under different operating conditions, effectively preventing phenomena such as air hammer oscillation, and ultimately ensuring smooth, precise, and frictionless movement of the cylinder.

[0051] In some embodiments of the frictionless cylinder for high-speed, high-acceleration motion of the present invention, see again Figure 1 As shown, the intake passage includes an intake pipe connector 15 disposed on the second piston rod guide sleeve 3 and a cylinder intake passage 16 communicating with the intake pipe connector 15. The intake pipe connector 15 is used to connect to an external precision pressure regulating valve. The exhaust passage includes an exhaust pipe connector 17 disposed on the second piston rod guide sleeve 3 and a cylinder exhaust passage 18 communicating with the exhaust pipe connector 17. The exhaust pipe connector 17 is used to connect to an external relief valve.

[0052] It is understood that in this embodiment of the frictionless cylinder for high-speed, high-acceleration motion, the intake and exhaust passages are compactly integrated on the second piston rod guide sleeve 3. The intake passage consists of an external intake pipe connector 15 and an internally machined cylinder intake air passage 16, with the intake pipe connector 15 specifically designed to connect to an external precision pressure regulating valve. Similarly, the exhaust passage consists of an external exhaust pipe connector 17 and an internal cylinder exhaust air passage 18, with the exhaust pipe connector 17 connecting to an external relief valve. This embodiment's method of centrally arranging key pneumatic interfaces on the same structural component creates a functionally clear and easily maintained integrated pneumatic circuit module.

[0053] During implementation, an external air source, via a precision pressure regulating valve, and through the intake pipe connector 15 and cylinder intake passage 16, provides stable and precisely controllable intake air to the high-pressure chamber 9 of the cylinder. When the cylinder requires high-speed, high-acceleration movement, the compressed gas in the high-pressure chamber 9 no longer relies solely on the precision pressure regulating valve at the intake port for difficult reverse discharge. Instead, it can quickly push open the overflow valve connected to the exhaust passage, achieving near-unobstructed rapid pressure relief through the cylinder exhaust passage 18 and exhaust pipe connector 17. This embodiment decouples the precise air supply and rapid exhaust functions, completely solving the severe throttling and deceleration effect generated by the precision pressure regulating valve in traditional cylinders during exhaust. This allows the cylinder to achieve extremely high instantaneous acceleration and movement speed, while the precision pressure regulating valve always operates under optimal conditions, ensuring precise control of the cylinder's air pressure, thus balancing ultra-precise movement and dynamic high-speed performance.

[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A frictionless cylinder for high-speed, high-acceleration motion, characterized in that, include: The cylinder body includes a cylinder body (1) and a first piston rod guide sleeve (2) and a second piston rod guide sleeve (3) respectively fixed at both ends of the cylinder body (1). A piston assembly is movably disposed within the cylinder body. The piston assembly includes a piston (4) and a first piston rod (5) and a second piston rod (6) respectively connected to both ends of the piston (4). The first piston rod (5) is movably inserted through the first piston rod guide sleeve (2), and a first gas static pressure bearing pair (7) is formed between the first piston rod (5) and the first piston rod guide sleeve (2); the second piston rod (6) is movably inserted through the second piston rod guide sleeve (3), and a second gas static pressure bearing pair (8) is formed between the second piston rod (6) and the second piston rod guide sleeve (3). The area between the first piston rod guide sleeve (2) and the second piston rod guide sleeve (3) forms a high-pressure chamber (9), and an annular gap (10) is formed between the piston (4) and the inner wall of the cylinder (1). The second piston rod guide sleeve (3) is provided with an air intake passage and at least one exhaust passage that communicate with the high-pressure chamber (9); Multiple throttling grooves (14) extending axially are provided on the inner walls of the first piston rod guide sleeve (2) and / or the second piston rod guide sleeve (3). The multiple throttling grooves (14) are evenly distributed circumferentially along the inner walls of the first piston rod guide sleeve (2) and / or the second piston rod guide sleeve (3). The gas in the high-pressure chamber (9) passes through the throttling grooves (14) and enters the first gas static pressure bearing pair (7) and / or the second gas static pressure bearing pair (8) to form a gas film.

2. The frictionless cylinder for high-speed, high-acceleration motion according to claim 1, characterized in that, The effective pressure-bearing area of ​​the end face of the piston (4) facing the second piston rod guide sleeve (3) is greater than the effective pressure-bearing area of ​​the end face of the piston (4) facing the first piston rod guide sleeve (2), so that after gas is introduced into the high-pressure chamber (9), a pressure difference is formed between the two end faces of the piston (4) to provide levitation force for the piston assembly.

3. The frictionless cylinder for high-speed, high-acceleration motion according to claim 1, characterized in that, The first end of the second piston rod (6) is connected to the piston (4) via a ball joint structure.

4. The frictionless cylinder for high-speed, high-acceleration motion according to claim 3, characterized in that, The ball joint structure includes a ball head (11) disposed at the first end of the second piston rod (6) and a ball pin seat (12) disposed on the end face of the piston (4), wherein the ball head (11) and the ball pin seat (12) constitute a spherical pair.

5. The frictionless cylinder for high-speed, high-acceleration motion according to claim 4, characterized in that, The second end of the second piston rod (6) is fitted with a spherical bearing (13) for connection with an external actuator.

6. The frictionless cylinder for high-speed, high-acceleration motion according to claim 1, characterized in that, The first piston rod guide sleeve (2) and the cylinder (1) are sealed by a seal, and the second piston rod guide sleeve (3) and the cylinder (1) are sealed by a seal; the first gas static pressure bearing pair (7) and the second gas static pressure bearing pair (8) are both surface throttling type static pressure bearings.

7. The frictionless cylinder for high-speed, high-acceleration motion according to claim 1, characterized in that, The cross-sectional shape of the throttling groove (14) is triangular, rectangular or trapezoidal.

8. The frictionless cylinder for high-speed, high-acceleration motion according to claim 1, characterized in that, The intake passage includes an intake pipe connector (15) disposed on the second piston rod guide sleeve (3) and a cylinder intake passage (16) communicating with the intake pipe connector (15). The intake pipe connector (15) is used to connect an external precision pressure regulating valve.

9. The frictionless cylinder for high-speed, high-acceleration motion according to claim 1, characterized in that, The exhaust passage includes an exhaust pipe connector (17) disposed on the second piston rod guide sleeve (3) and a cylinder exhaust flow passage (18) communicating with the exhaust pipe connector (17). The exhaust pipe connector (17) is used to connect an external overflow valve.

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