A high-sealing floating joint for cylinders

Abstract

This utility model relates to the field of floating joint technology and discloses a high-sealing floating joint for cylinders, including a housing. A connecting pipe is fixedly connected to the right side of the housing, and a cylinder is disposed on the right side of the connecting pipe. A piston is fixedly connected to the output end of the cylinder. A sealing cover is fixedly connected to the left outer wall of the housing, and retaining rings are fixedly connected to the left and right outer walls inside the housing. In this utility model, the connection between the connecting pipe and the cylinder is reinforced through the transmission cooperation of the rotating shaft, gears, racks and pinions and the extrusion block, effectively preventing the connection from loosening. At the same time, the free rotation of the ball within the retaining ring can drive the stud to complete multi-angle adjustment, adapting to the position changes of the external structure under different working conditions, avoiding stress concentration or connection failure caused by fixed angles. In addition, the sealing sleeve of the stud and the sealing cover of the housing form a double sealing structure, significantly improving the overall sealing performance of the joint and meeting the stringent requirements of the cylinder for the sealing environment.

Description

Technical Field

[0001] This utility model relates to the field of floating joint technology, specifically a high-sealing floating joint for cylinders. Background Technology

[0002] A cylinder is a cylindrical metal component that guides a piston in a linear reciprocating motion within its casing. In an engine cylinder, air expands, converting thermal energy into mechanical energy; in a compressor cylinder, gas is compressed by a piston, increasing its pressure. The casing of turbines, rotary piston engines, and similar devices is also commonly referred to as a "cylinder." Applications of cylinders include: printing (tension control), semiconductors (spot welding machines, chip grinding), automation control, robotics, and more.

[0003] Cylinders are common power sources in various machine tools, used to drive other components in linear reciprocating motion. When the direction of the cylinder's driving force and the point of application are not on a straight line, the shaft is prone to deformation. Ordinary joints cannot solve this problem, while floating joints can absorb or correct the misalignment, achieving a flexible connection, protecting related components and equipment, ensuring smooth operation, and extending equipment lifespan. However, traditional floating joints have a simple sealing structure, and even slight loosening can easily cause air leakage, affecting use. Therefore, floating joints with high sealing performance are needed to ensure the normal operation of the cylinder.

[0004] The existing method causes the gap between the connecting pipe and the cylinder interface to gradually widen, and the fasteners (such as bolts) to continuously loosen due to the "vibration loosening effect", eventually causing the connecting pipe to shift or even fall off, directly interrupting the cylinder power transmission, causing the equipment to stop, making it impossible to perform auxiliary fixing, and prolonging the installation time.

[0005] To address the aforementioned issues, a high-sealing floating joint for cylinders is proposed. Utility Model Content

[0006] The purpose of this invention is to provide a high-sealing floating joint for cylinders, which solves the problem in the prior art that it is impossible to perform auxiliary fixing and that prolongs the installation time.

[0007] To achieve the above objectives, this utility model provides the following technical solution: a high-sealing floating joint for a cylinder, comprising a housing, a connecting pipe fixedly connected to the right side of the housing, a cylinder disposed on the right side of the connecting pipe, a piston fixedly connected to the output end of the cylinder, a sealing cover fixedly connected to the left outer wall of the housing, retaining rings fixedly connected to the left and right outer walls inside the housing, a ball rotatably connected inside the retaining ring, a stud fixedly connected to the left outer wall of the ball, a sealing sleeve fixedly connected to the right outer wall of the stud, and an auxiliary component disposed on the right outer wall of the connecting pipe.

[0008] By adopting the above technical solution, the sealing performance of the cylinder floating joint can be significantly improved. The retaining rings on the left and right sides of the outer shell can stably support the rotation of the ball and meet the multi-angle adjustment requirements of the joint; the stud on the left side of the ball facilitates connection with external components, and the sealing sleeve on its right side can effectively prevent external dust and moisture from entering the inner shell. Together with the sealing cover on the left side, a double sealing structure is formed.

[0009] As a further description of the above technical solution: the auxiliary component includes a first connecting frame, which is fixedly connected to the outer wall of the connecting pipe. The outer wall of the first connecting frame is fixedly connected to evenly distributed connecting blocks. The outer wall of the connecting blocks is fixedly connected to a second connecting frame. A rotating shaft is rotatably connected inside the top connecting block.

[0010] By adopting the above technical solution, the stability of the connection between the connecting pipe and the cylinder can be enhanced.

[0011] As a further description of the above technical solution: a universal joint is fixedly connected between the rotating shafts, and a gear is fixedly connected to the outer ring of the rotating shaft.

[0012] By adopting the above technical solutions, the adjustment flexibility and connection stability of auxiliary components can be further improved.

[0013] As a further description of the above technical solution: a guide block is fixedly connected to the outer wall of the second connecting frame.

[0014] By adopting the above technical solution, its deviation trajectory is limited, ensuring a smooth and orderly adjustment process.

[0015] As a further description of the above technical solution: a rack is slidably connected to the outer wall of the guide block, and the rack is meshed with a gear; a pressing block is fixedly connected to one end of the rack.

[0016] By adopting the above technical solution, precise locking and adjustment of the connection structure can be achieved.

[0017] As a further description of the above technical solution: a rotating disk is fixedly connected to the outer wall of the top rotating shaft.

[0018] By adopting the above technical solution, rotation is achieved through a rotating disk.

[0019] As a further description of the above technical solution: the outer wall of the connecting block at the top is fixedly connected to a limiting sleeve, and the limiting sleeve is rotatably connected to the rotating shaft.

[0020] By adopting the above technical solution, the rotating shaft is limited and controlled by the limiting sleeve.

[0021] As a further description of the above technical solution: the limiting sleeve is connected to the internal thread of the rotating disk by bolts.

[0022] By adopting the above technical solution, the rotating disk and rotating shaft are limited and controlled by the limiting sleeve and bolt.

[0023] Compared with the prior art, the beneficial effects of this utility model are as follows: This utility model provides a high-sealing floating joint for cylinders. First, through the transmission and cooperation of the rotating shaft, gears, racks and extrusion blocks, a reinforced connection between the connecting pipe and the cylinder is achieved, effectively preventing loosening of the connection. At the same time, the free rotation of the ball within the retaining ring can drive the stud to complete multi-angle adjustment, adapting to the positional changes of the external structure under different working conditions, avoiding stress concentration or connection failure caused by fixed angles. In addition, the sealing sleeve of the stud and the sealing cover of the outer shell form a double sealing structure, significantly improving the overall sealing performance of the joint and meeting the stringent requirements of the cylinder for the sealing environment. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a schematic diagram of the overall cross-sectional structure of this utility model; Figure 3 This is a schematic diagram of the sealing cover of this utility model; Figure 4 This is a schematic diagram of the structure of the first connecting frame of this utility model.

[0025] In the diagram: 1. Outer shell; 2. Connecting pipe; 3. Sealing sleeve; 4. Cylinder; 5. Piston; 6. Stud; 7. Retaining ring; 8. Sealing cover; 9. Ball; 10. First connecting frame; 11. Second connecting frame; 12. Connecting block; 13. Universal joint; 14. Guide block; 15. Rack; 16. Gear; 17. Rotating shaft; 18. Rotating disk; 19. Limiting sleeve; 20. Bolt; 21. Extrusion block. Detailed Implementation

[0026] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0027] To further understand the contents of this utility model, a detailed description of this utility model will be provided with reference to the accompanying drawings.

[0028] Reference Figures 1-4This utility model discloses a high-sealing floating joint for cylinders, comprising a housing 1. A connecting pipe 2 is fixed to the right end face of the housing 1 by welding. During welding, the coaxiality error between the connecting pipe 2 and the housing 1 must be ensured to be no more than 0.05mm, and the weld joint must be inspected for defects such as pores and cracks to ensure no leakage channels for gas or liquid. A sealing cover 8 is fixed to the left outer wall of the housing 1 by bolts. The contact surface between the sealing cover 8 and the housing 1 must be coated with high-pressure resistant sealant, with the sealant thickness controlled at 0.1-0.2mm, and it must be evenly covered on the contact surface. After the sealant has cured (curing time no less than 24 hours, curing environment temperature 25±5℃, relative humidity 40%-60%), the connection and sealing performance between the sealing cover 8 and the housing 1 must be checked to ensure there is no risk of loosening or seal failure. The inner walls of the left and right sides of the outer casing 1 have pre-set mounting grooves. The retaining ring 7 is embedded into the mounting groove, and the retaining ring 7 and the mounting groove are interference-fitted (interference amount is 0.02-0.03mm). During assembly, a special pressing equipment is required to slowly press it in with a pressure of 5-8kN to avoid deformation of the retaining ring 7. After pressing, the roundness error of the inner hole of the retaining ring 7 must be checked to ensure that it does not exceed 0.01mm, so as to provide stable support for the rotation of the ball 9. The ball 9 is then installed into the inner hole of the retaining ring 7. The fit clearance between the ball 9 and the inner hole of the retaining ring 7 must be controlled within 0.005-0.01mm. Before assembly, a high-temperature resistant and wear-resistant grease should be applied to the surface of the ball 9. The amount of grease should cover 1 / 3 to 1 / 2 of the surface of the ball 9 to ensure that the ball 9 can rotate flexibly in the retaining ring 7 without any jamming. A stud 6 is fixed to the outer left side of the ball 9 by a threaded connection. Thread sealant should be applied to the threaded connection. After tightening, the coaxiality of the stud 6 and the ball 9 should be checked, and the error should not exceed 0.03mm. At the same time, a sealing sleeve 3 is fitted onto the outer right side of the stud 6. The sealing sleeve 3 is made of fluororubber, and its inner diameter is an interference fit with the outer wall of the stud 6 (interference amount is 0.01-0.02mm). During assembly, it is necessary to ensure that the sealing sleeve 3 is completely fitted to the outer wall of the stud 6, with one end in close contact with the left end face of the ball 9 and the other end in contact with the inner left end face of the outer shell 1, to achieve a preliminary seal.

[0029] Auxiliary component assembly Select the first connecting bracket 10 and fix it to the outer wall of the connecting pipe 2 by means of a clamp structure. The tightening torque of the clamp bolt is 8-12 N·m. After fixing, the coaxiality of the first connecting bracket 10 and the connecting pipe 2 needs to be checked. The error should not exceed 0.1 mm. The first connecting bracket 10 should be tightly fitted to the outer wall of the connecting pipe 2 without gaps.

[0030] Connecting blocks 12 are welded to the outer wall of the first connecting frame 10. The connecting blocks 12 are evenly distributed along the circumference of the first connecting frame 10, with a quantity of no less than 3. The included angle error between adjacent connecting blocks 12 does not exceed ±2°. The welding adopts argon arc welding process, and the weld leg height is 3-5mm. After welding, the weld joint needs to be ground to remove welding slag and burrs.

[0031] A second connecting frame 11 is welded to the end of the connecting block 12 away from the first connecting frame 10. The perpendicularity error between the second connecting frame 11 and the connecting block 12 shall not exceed 0.05mm. The welding process and post-weld treatment requirements are the same as those for welding the connecting block 12 and the first connecting frame 10, to ensure that the second connecting frame 11 is stable and has an accurate posture.

[0032] A bearing mounting hole is pre-set inside the top connecting block 12, and a deep groove ball bearing is installed. The outer ring of the bearing is interference-fitted with the mounting hole (interference amount 0.005-0.01mm), and the inner ring is transition-fitted with the shaft 17. The shaft 17 is passed through the inner ring of the bearing to realize the rotational connection between the shaft 17 and the connecting block 12. After assembly, the radial runout of the shaft 17 needs to be checked and should not exceed 0.02mm to ensure that the shaft 17 rotates smoothly.

[0033] Adjacent shafts 17 are connected by universal joints 13. Both ends of the universal joint 13 are connected to the shafts 17 by keys. The fit clearance between the key and the keyway is 0.01-0.02mm. After assembly, the rotational flexibility of the universal joint 13 needs to be checked to ensure that it can rotate without jamming within a range of ±30° and can effectively transmit torque.

[0034] Gear 16 is fixed to the outer ring of shaft 17 via a flat key. The fit between the flat key and the keyway is the same as that between universal joint 13 and shaft 17. The end face of gear 16 must fit tightly with the shoulder of shaft 17 without any gap. After assembly, the radial runout and end face runout of gear 16 must be checked and should not exceed 0.02mm and 0.015mm respectively to ensure the transmission accuracy of gear 16. Guide block 14 is fixed to the outer wall of second connecting bracket 11 via bolts. Guide groove is pre-set on guide block 14. The straightness error of guide groove should not exceed 0.01mm. The groove width and the thickness of rack 15 should fit with a clearance of 0.01-0.02mm to ensure that rack 15 can slide smoothly along guide groove. Insert rack 15 into the guide groove of guide block 14, adjust the position of rack 15 so that rack 15 and gear 16 are fully engaged, with the meshing gap controlled at 0.05-0.1mm and the meshing contact area not less than 70%, ensuring that gear 16 can stably drive rack 15 to slide when rotating. At the end of rack 15 furthest from gear 16, weld and fix extrusion block 21. The extrusion surface of extrusion block 21 needs to be machined for flatness, with a flatness error not exceeding 0.01mm, and wear-resistant shims with a thickness of 1-2mm need to be attached to the extrusion surface to enhance the extrusion fixing effect and wear resistance. At the end of top rotating shaft 17 furthest from universal joint 13, fix rotating disk 18 by threaded connection. The thread tightening torque is 10-15 N·m. After tightening, check the coaxiality of rotating disk 18 and rotating shaft 17, with an error not exceeding 0.05mm, ensuring that rotating disk 18 can synchronously drive rotating shaft 17 when rotating. A limiting sleeve 19 is welded to the outer wall of the top connecting block 12. The inner hole of the limiting sleeve 19 and the rotating shaft 17 are clearance fit (clearance 0.02-0.03mm). The distance between the end face of the limiting sleeve 19 and the rotating disk 18 is controlled at 1-2mm. The welding requirements are the same as before to ensure that the limiting sleeve 19 is stable and does not affect the rotation of the rotating disk 18. Coaxial threaded holes are pre-set on the limiting sleeve 19 and the rotating disk 18. The threaded hole accuracy is 6H, which is used to install bolts 20 to achieve the limiting.

[0035] Cylinder connection and assembly The assembled floating joint is connected to the cylinder 4 via connecting pipe 2. The interface between connecting pipe 2 and cylinder 4 is connected by a flange. A metal spiral wound gasket must be placed on the flange sealing surface. The gasket material is 304 stainless steel + graphite to ensure sealing performance. The flange bolts must be tightened in a diagonal sequence in stages. The tightening torque is 25-30 N·m. A torque wrench must be used to control the torque accuracy to avoid uneven bolt force leading to seal failure.

[0036] Rotate the rotating disk 18, which drives the top rotating shaft 17 to rotate. The top rotating shaft 17 drives the other rotating shafts 17 to rotate synchronously through the universal joint 13. When the rotating shaft 17 rotates, the gear 16 fixed on its outer ring rotates accordingly. The gear 16 meshes with the rack 15, driving the rack 15 to slide along the guide groove of the guide block 14 toward the piston 5 at the output end of the cylinder 4, until the pressing block 21 at one end of the rack 15 is in close contact with the outer wall of the piston 5. At this time, stop rotating the rotating disk 18.

[0037] Bolts 20 are installed in the pre-threaded holes of the limiting sleeve 19 and the rotating disk 18. Bolts 20 are internal hexagonal head bolts made of high-strength alloy steel. The tightening torque of bolts 20 is 8-10 N·m. The rotating disk 18 and the limiting sleeve 19 are fixedly connected by bolts 20, thereby restricting the rotation of the rotating shaft 17 and keeping the extrusion block 21 in a state of extrusion on the piston 5, thus achieving the fastening of the connecting pipe 2 and the cylinder 4.

[0038] Post-assembly inspection Sealing test: The overall sealing of the floating joint is tested using airtightness testing equipment. The test pressure is 1.2 times the rated working pressure of cylinder 4, and the pressure holding time is not less than 30 minutes. During this period, the soap bubble method or pressure sensor is used to check whether there is leakage at each sealing part (the interface between connecting pipe 2 and cylinder 4, the contact between sealing sleeve 3 and outer shell 1 and stud 6, and the interface between sealing cover 8 and outer shell 1). The pressure drop is required to be no more than 1% of the test pressure, and no obvious soap bubbles are generated.

[0039] Rotation flexibility test: Manually push the stud 6 and observe the rotation of the ball 9 within the retaining ring 7. The stud 6 should be able to rotate flexibly within a range of ±15° without any jamming or abnormal noise. At the same time, check the fit between the sealing sleeve 3 and the outer shell 1 and the stud 6 when the stud 6 rotates to ensure that the sealing sleeve 3 does not shift or deform and can still maintain an effective seal.

[0040] Connection stability test: Perform no-load reciprocating motion test on cylinder 4, with no less than 1000 motions, and each motion stroke is 80% of the maximum stroke of cylinder 4; after the motion is completed, check the connection status between connecting pipe 2 and cylinder 4 (flange bolt torque, and the fit between pressing block 21 and piston 5). The flange bolt torque attenuation should not exceed 5%, and the pressing block 21 should not be loose or displaced to ensure connection stability.

[0041] Working principle: It can drive the rotating shaft 17 to rotate synchronously; because the outer ring of the rotating shaft 17 is fixed with a gear 16, and the guide block 14 fixed on the outer wall of the second connecting frame 11 slides and engages with the rack 15, and the rack 15 meshes with the gear 16, the rotation of the rotating shaft 17 will drive the gear 16 to rotate, and then drive the rack 15 to slide along the guide direction of the guide block 14; the pressing block 21 fixed at one end of the rack 15 slides with the rack 15 toward the piston 5 until it is in close contact with the outer wall of the piston 5, and the connection between the connecting pipe 2 and the cylinder 4 is reinforced by the pressing force to prevent auxiliary installation. Then, the rotating disk 18 and the rotating shaft 17 are limited and controlled by the limiting sleeve 19 and the bolt 20. When the cylinder 4 runs, the piston 5 fixed at its output end reciprocates. The motion force is transmitted to the inside of the outer shell 1 through the connecting pipe 2, providing the power basis for the subsequent action of the connector. The retaining rings 7 fixed to the outer walls on both sides inside the outer shell 1 provide precise positioning and stable support for the ball 9, allowing the ball 9 to rotate freely within the retaining rings 7. The stud 6 fixed to the outer wall on the left side of the ball 9 is used to connect to the external structure to be mated. The rotation of the ball 9 can drive the stud 6 to achieve multi-angle adjustment, thereby adapting to the positional changes of the external structure under different working conditions and avoiding stress concentration or connection failure caused by a fixed connection angle. The sealing sleeve 3 fixed to the outer wall on the right side of the stud 6 can fill the gap between the stud 6 and the outer shell 1, effectively preventing gas or liquid from leaking from this part. At the same time, the sealing cover 8 fixed to the outer wall on the left side of the outer shell 1 forms a secondary sealing protection for the connection area of ​​the ball 9, the stud 6 and the outer shell 1. The double sealing structure significantly improves the overall sealing performance of the joint and meets the stringent requirements of the sealing environment when the cylinder is working.

[0042] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0043] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-sealing floating joint for a cylinder, comprising a housing (1), characterized in that: A connecting pipe (2) is fixedly connected to the right side of the outer shell (1). A cylinder (4) is provided on the right side of the connecting pipe (2). A piston (5) is fixedly connected to the output end of the cylinder (4). A sealing cover (8) is fixedly connected to the left outer wall of the outer shell (1). A retaining ring (7) is fixedly connected to both the left and right outer walls inside the outer shell (1). A ball (9) is rotatably connected inside the retaining ring (7). A stud (6) is fixedly connected to the left outer wall of the ball (9). A sealing sleeve (3) is fixedly connected to the right outer wall of the stud (6). An auxiliary component is provided on the right outer wall of the connecting pipe (2).

2. A high-sealing floating joint for a cylinder according to claim 1, characterized in that: The auxiliary component includes a first connecting frame (10), which is fixedly connected to the outer wall of the connecting pipe (2). The outer wall of the first connecting frame (10) is fixedly connected to a uniformly distributed connecting block (12). The outer wall of the connecting block (12) is fixedly connected to a second connecting frame (11). The top of the connecting block (12) is rotatably connected to a rotating shaft (17).

3. A high-sealing floating joint for a cylinder according to claim 2, characterized in that: A universal joint (13) is fixedly connected between the rotating shafts (17), and a gear (16) is fixedly connected to the outer ring of the rotating shafts (17).

4. A high-sealing floating joint for a cylinder according to claim 2, characterized in that: The second connecting frame (11) has a guide block (14) fixedly connected to its outer wall.

5. A high-sealing floating joint for a cylinder according to claim 4, characterized in that: The guide block (14) has a rack (15) slidably connected to its outer wall, and the rack (15) meshes with the gear (16). One end of the rack (15) is fixedly connected to a pressing block (21).

6. A high-sealing floating joint for a cylinder according to claim 2, characterized in that: A rotating disk (18) is fixedly connected to the outer wall of the rotating shaft (17) at the top.

7. A high-sealing floating joint for a cylinder according to claim 2, characterized in that: The outer wall of the connecting block (12) at the top is fixedly connected to a limiting sleeve (19), and the limiting sleeve (19) is rotatably connected to the rotating shaft (17).

8. A high-sealing floating joint for a cylinder according to claim 7, characterized in that: The limiting sleeve (19) is internally threaded with a bolt (20) to the rotating disk (18).

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