Intermittent bidirectional pressure-bearing axial limiter and manufacturing method thereof

Abstract

The invention provides an intermittent bidirectional-pressure-bearing axial limiter and a manufacturing method thereof. The intermittent bidirectional-pressure-bearing axial limiter comprises a cylindrical outer shell, an inner shaft, two spring force transmission sliding lantern rings and a spring, wherein the two ends of the cylindrical outer shell are open; the inner shaft is arranged in the outer shell in a penetrating mode, the inner shaft is sleeved with the two spring force transmission sliding lantern rings, and the two spring force transmission sliding lantern rings are in clearance fit with the inner shaft and the outer shell respectively; the limiting action stroke is L, the total compression amount of the spring is S, the compression rigidity is K, and the lantern ring has the sliding bearing function. According to the working principle, under the action of bidirectional axial force, when the relative movement value of the inner shaft between the middle balance position and the outer cylinder is larger than or equal to L, the inner shaft drives the corresponding lantern ring to compress the spring, the spring absorbs impact energy to achieve buffering limiting, and after the force disappears, the spring resets to drive the inner shaft to return to the initial position. The same group of springs can be pressed and limited bidirectionally, the internal structure is simple, the buffering and damping performance is excellent, and the two-way axial buffering and limiting device can be widely applied to various related engineering scenes needing two-way axial buffering and limiting constraint.

Description

Technical Field

[0001] This invention relates to the field of limiter technology, and in particular to an intermittent, bidirectionally compressible axial limiter and its manufacturing method. Background Technology

[0002] Axial limiting is a crucial element in ensuring stable operation of mechanical equipment or engineering structures. In many scenarios, core components need to move within a specific axial range. Without effective axial limiting measures, excessive axial movement of components can easily lead to direct structural collisions, accelerated wear of parts, and decreased control precision. In severe cases, it can cause equipment malfunctions and shutdowns, and even create safety hazards.

[0003] However, existing axial limiting technologies have several insurmountable drawbacks: First, most traditional limiters can only achieve unidirectional axial limiting, which cannot adapt to complex working conditions with bidirectional forces, thus limiting their applicability. Second, some limiters lack effective buffer structures or have unreasonable performance parameters for the elastic elements, resulting in weak energy absorption capacity when subjected to axial impact loads, with the impact force directly transmitted to the equipment body, easily causing irreversible damage such as component deformation and breakage. Third, a single elastic element in common limiters can only achieve unidirectional axial compression limiting, and cannot simultaneously achieve bidirectional axial compression limiting. Fourth, some devices with bidirectional limiting functions have complex structural designs, including multiple transmission or locking mechanisms, and require a large space, leading to high manufacturing costs, difficult assembly, and inconvenient maintenance, thus increasing the operating costs of the equipment.

[0004] Therefore, there is an urgent need to develop an axial limiting device that combines bidirectional limiting capability, excellent buffering and shock absorption performance, and is simple in structure, low in cost, and easy to manufacture and maintain, so as to meet the actual needs of mechanical equipment for efficient and reliable axial limiting and fill the gap in existing technology. Summary of the Invention

[0005] This invention provides an intermittent, bidirectional pressure-bearing axial limiter and its manufacturing method, in order to overcome the deficiencies in the prior art.

[0006] The present invention provides an intermittent bidirectional compressible axial limiter, comprising an outer shell, an inner shaft, two sliding collars, and an elastic element; The outer shell is a cylindrical structure with openings at both ends. The inner shaft passes through the interior of the outer shell, and there is an axial working space between the inner shaft and the outer shell, allowing the inner shaft to move axially relative to the outer shell. The initial stroke of this axial working space is L. The outer shell is made of high-strength steel, and the inner shaft is made of alloy steel with good wear resistance. Both spring-transmitting sliding collars are sleeved on the inner shaft and located inside the outer shell. The spring-transmitting sliding collars can slide flexibly along the outer and inner shafts and can bear radial and axial loads. The spring-transmitting sliding collars are made of alloys such as copper. The outer surface of the spring-transmitting sliding collars has undergone surface treatment. The elastic element is a spring, which is installed between two spring force transmission sliding collars, and the two ends of the spring respectively abut against the corresponding spring force transmission sliding collars; the total compression of the spring is S, and the compression stiffness is K.

[0007] According to the present invention, an intermittent bidirectional pressure-bearing axial limiter is provided, wherein the spring-transmitting sliding collar also functions as a double sliding bearing.

[0008] According to the present invention, an intermittent bidirectional pressure-bearing axial limiter is provided, wherein the surface roughness and outer diameter accuracy of the inner shaft meet the matching requirements with the spring force-transmitting sliding collar.

[0009] According to the present invention, an intermittent bidirectional pressure-bearing axial limiter is provided, wherein the inner diameter of the outer shell is precisely machined according to the outer diameter of the inner shaft and the design clearance.

[0010] A method for manufacturing the intermittent, bidirectional compressible axial limiter as described above is provided, comprising the following steps: (1) Component manufacturing: a. Outer shell processing: High-strength steel is selected and processed into a cylindrical outer shell with open ends and hollow interior through machining. The inner diameter of the outer shell is precisely processed according to the outer diameter of the inner shaft and the design clearance. b. Inner shaft machining: Select wear-resistant alloy steel material and machine according to the design dimensions to ensure the accuracy of the outer diameter and surface roughness of the inner shaft; c. Spring force transmission sliding collar machining: Select alloy materials such as copper, form by casting or machining, machine the inner hole of the collar to fit the inner shaft, and perform surface treatment on the outer surface of the collar. d. Spring fabrication: Based on the design requirements of total compression S and compression stiffness K, select appropriate spring steel wire and manufacture the spring through winding and heat treatment processes; (2) Assembly process: a. Place the two machined spring-transmitting sliding collars onto the machined inner shaft, ensuring that the collars can slide freely along the inner shaft; b. Install the prepared spring between the two spring force transmission sliding collars, so that the two ends of the spring are respectively pressed against the corresponding collars; c. Install the inner shaft, which consists of the spring-loaded sliding collar and the spring, into the outer casing, ensuring a uniform gap between the inner shaft and the outer casing to complete the assembly.

[0011] According to the manufacturing method of an intermittent bidirectional pressure-bearing axial limiter provided by the present invention, in step (1)a, the machining includes cutting, drilling and grinding processes.

[0012] According to the manufacturing method of an intermittent bidirectional pressure-bearing axial limiter provided by the present invention, in step (1)b, the turning process further includes polishing of the shaft surface.

[0013] According to the manufacturing method of an intermittent bidirectional pressure-bearing axial limiter provided by the present invention, in step (1)c, the surface treatment is a hardening and polishing process; the inner hole size tolerance of the spring force transmission sliding collar is controlled within the design threshold range.

[0014] According to the manufacturing method of an intermittent bidirectional pressure-bearing axial limiter provided by the present invention, in step (2)a, before the spring force transmission sliding collar is fitted, the surface of the central shaft and the inner hole of the collar are cleaned.

[0015] According to the manufacturing method of an intermittent bidirectional pressure-bearing axial limiter provided by the present invention, in step (2)c, after assembly, the axial movement flexibility of the inner shaft relative to the outer shell needs to be tested.

[0016] This invention provides an intermittent, bidirectional compressible axial limiter and its manufacturing method. Through a symmetrical structural design of "inner shaft-spring-force-sliding collar-spring-spring-force-sliding collar," it can simultaneously withstand both positive and negative axial forces. Regardless of the axial movement tendency of the equipment component, effective limiting can be achieved through the compression of the same spring unit, completely solving the limitation of traditional limiters' unidirectional limiting. It can be widely used in reciprocating motion mechanisms, bidirectional impact equipment, precision transmission systems, and other mechanical equipment requiring bidirectional axial constraint, exhibiting extremely high applicability and versatility. A spring with a total compression of S and a compression stiffness of K is specifically designed as the elastic element. These parameters match the axial load characteristics of most mechanical equipment, enabling efficient absorption and buffering of axial impact energy. When subjected to impact load, the spring converts axial kinetic energy into elastic potential energy through elastic deformation, significantly weakening the impact force on the equipment component. When the load disappears, the spring elastically returns to its original position, preventing rigid collisions of the components. This significantly reduces the risk of wear and fatigue damage to equipment components, effectively extending the service life of the limiter itself and related equipment or components. This limit switch consists of only four core components: the outer shell, the inner shaft, two spring-loaded sliding collars, and the springs themselves. It avoids redundant and complex structures, has fewer parts, and simpler assembly relationships, reducing manufacturing difficulty and production costs. Furthermore, each component adopts a modular design; the outer shell, inner shaft, spring-loaded sliding collars, and springs can all be independently machined, disassembled, and replaced. During later maintenance, there is no need to disassemble the entire device; only damaged parts need to be inspected or replaced individually, greatly simplifying the maintenance process, shortening downtime for maintenance, and reducing equipment operation and maintenance costs. The core components are made of suitable high-performance materials, and with precise dimensional machining, the spring-loaded sliding collars can slide flexibly along the inner shaft while possessing both radial and axial load-bearing capacity, avoiding problems such as movement jamming or insufficient load-bearing capacity, and ensuring stable operation of the limit switch under long-term, high-frequency working conditions. Attached Figure Description

[0017] 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.

[0018] Figure 1 This is a schematic diagram of the intermittent bidirectional compressible axial limiter provided in an embodiment of the present invention; Figure 2 This is a cross-sectional structural schematic diagram of the intermittent bidirectional compressible axial limiter provided in an embodiment of the present invention.

[0019] Figure label: 1. Outer shell; 2. Inner shaft; 3. Spring-transmitting sliding collar; 4. Elastic element. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0021] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0022] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0023] In the description of the embodiments of the present invention, it should be noted that the terms "inner", "outer", "upper", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the present invention.

[0024] This application provides an intermittent bidirectional pressure-bearing axial limiter, which mainly includes an outer shell 1, an inner shaft 2, two spring-transmitting sliding collars 3, and an elastic element 4. The outer shell 1 is a cylindrical structure with openings at both ends. The inner shaft 2 passes through the interior of the outer shell 1, and there is an axial working space between the inner shaft 2 and the outer shell 1, allowing the inner shaft 2 to move axially relative to the outer shell 1. The initial stroke of this axial working space is L. The outer shell 1 is made of high-strength steel. The inner shaft 2 is made of alloy steel with good wear resistance. Both spring-transmitting sliding collars 3 are sleeved on the inner shaft 2 and located inside the outer shell 1. The spring-transmitting sliding collars 3 can slide flexibly along the outer shell 1 and the inner shaft 2 and can bear radial and axial loads. The spring-transmitting sliding collars 3 are made of alloys such as copper. The outer surface of the spring-transmitting sliding collars 3 has undergone surface treatment. The elastic element 4 is a spring, which is installed between the two spring force transmission sliding collars 3, and the two ends of the spring respectively abut against the corresponding spring force transmission sliding collars 3; the total compression of the spring is S, and the compression stiffness is K.

[0025] To further optimize the above technical solution, the spring-transmitting sliding collar 3 also functions as a double sliding bearing.

[0026] To further optimize the above technical solution, the surface roughness and outer diameter accuracy of the inner shaft 2 meet the matching requirements with the spring force transmission sliding collar 3.

[0027] To further optimize the above technical solution, the inner diameter of the outer shell 1 is precisely machined according to the outer diameter of the inner shaft 2 and the design clearance.

[0028] Specifically, the outer shell 1 is a cylindrical structure with openings at both ends, serving as the mounting reference and external protective component for the entire limiter, providing stable mounting space and support for the internal components; the inner shaft 2 passes through the inner shell 1, with a uniform gap reserved between it and the outer shell 1. This gap provides the necessary stroke for the axial movement of the inner shaft 2, while avoiding direct friction between the inner shaft 2 and the outer shell 1; two spring-loaded sliding collars 3 are fitted onto the inner shaft 2, possessing both the characteristic of flexible sliding along the inner shaft 2 and the ability to bear radial and axial loads, playing a dual role of force transmission and guidance; the springs are installed between the two collars, with their ends tightly abutting against the collars, forming a symmetrical elastic buffer structure.

[0029] Bidirectional force limiting and buffering process: When the limiter is subjected to a positive axial force, the force is transmitted to the inner shaft 2, pushing the inner shaft 2 to move along the positive axial direction; when the displacement value exceeds L, the inner shaft 2 drives the spring-transmitting sliding collar 3 on one side to move synchronously, causing the collar on that side to squeeze the spring towards the collar on the other side; the spring undergoes elastic compression under axial pressure, converting axial kinetic energy into elastic potential energy, realizing the absorption and buffering of impact force, while the reverse elastic force generated by the spring gradually increases until it is balanced with the external axial force or the spring is fully compressed to the value S, and the inner shaft 2 stops moving, thereby limiting the maximum positive axial displacement of the inner shaft 2.

[0030] When the limit switch moves in the reverse direction from the full stroke condition, the force transmission path is symmetrical with the forward force: the reverse axial force pushes the inner shaft 2 to move in the reverse direction. When the displacement value exceeds (S+2L), it drives the spring-transmitting sliding collar 3 on the other side to squeeze the spring. The spring also absorbs the impact energy through elastic compression and generates a reverse elastic force to counteract the external load and limit the maximum reverse axial displacement of the inner shaft 2.

[0031] Reset process: When the external axial force disappears, the elastic potential energy stored in the spring is released, and the spring returns to its initial free length. Through the spring force transmission sliding collars 3 at both ends, the inner shaft 2 is pushed to move in the opposite direction until the inner shaft 2 returns to its initial axial position, completing the reset and preparing for the next limit action.

[0032] Throughout the entire operation, the compression and stiffness parameters of the spring ensure a precise match between the buffering effect and the limiting stroke. The sliding bearing function of the spring force transmission sliding collar 3 ensures the smooth transmission of force and the smooth movement of the inner shaft 2. The gap design between the outer shell 1 and the inner shaft 2 avoids motion interference, ultimately realizing the functions of bidirectional limiting, buffering and shock absorption, and automatic reset.

[0033] A method for manufacturing the intermittent, bidirectional compressible axial limiter as described above is provided, comprising the following steps: (1) Component manufacturing: a. Outer shell 1 processing: High-strength steel is selected and processed into a cylindrical outer shell 1 with open ends and hollow interior by mechanical processing. The inner diameter of the outer shell 1 is precisely processed according to the outer diameter of the inner shaft 2 and the design clearance. b. Machining of inner shaft 2: Select alloy steel with good wear resistance and machine it according to the design dimensions to ensure the accuracy of the outer diameter and surface roughness of inner shaft 2; c. Processing of spring-transmitting sliding collar 3: Select alloy materials such as copper, form by casting or machining, process the inner hole of the collar to fit the inner shaft 2, and perform surface treatment on the outer surface of the collar. d. Spring fabrication: Based on the design requirements of total compression S and compression stiffness K, select appropriate spring steel wire and manufacture the spring through winding and heat treatment processes; (2) Assembly process: a. Place the two finished spring-transmitting sliding collars 3 onto the finished inner shaft 2, ensuring that the collars can slide freely along the inner shaft 2; b. Install the prepared spring between the two spring force transmission sliding collars 3, so that the two ends of the spring abut against the corresponding collars respectively; c. As a whole, insert the inner shaft 2, which is assembled with the spring-transmitting sliding collar 3 and the spring, into the outer shell 1, ensuring that the gap between the inner shaft 2 and the outer shell 1 is uniform, and complete the assembly.

[0034] To further optimize the above technical solution, in step (1)a, the machining includes cutting, drilling and grinding processes.

[0035] To further optimize the above technical solution, in step (1)b, the turning process also includes polishing the shaft surface.

[0036] To further optimize the above technical solution, in step (1)c, the surface treatment is a hardening and polishing process; the inner hole size tolerance of the spring force transmission sliding collar 3 is controlled within the design threshold range.

[0037] To further optimize the above technical solution, in step (2)a, before installing the spring force transmission sliding collar 3, the surface of the central shaft and the inner hole of the collar are cleaned.

[0038] To further optimize the above technical solution, in step (2)c, after assembly, it is necessary to test the axial movement flexibility of the inner shaft 2 relative to the outer shell 1.

[0039] As can be seen, the intermittent bidirectional compressible axial limiter and its manufacturing method provided by this invention, through the symmetrical structural design of "inner shaft 2 - spring force transmission sliding collar 3 - spring - spring force transmission sliding collar 3", can simultaneously withstand positive and negative axial forces. Regardless of the axial movement tendency of the equipment component, effective limiting can be achieved through spring compression, completely solving the limitation of unidirectional limiting of traditional limiters. It can be widely used in various mechanical equipment or engineering devices that require bidirectional axial constraint, such as reciprocating motion mechanisms, bidirectional impact equipment, and precision transmission systems, and has extremely strong applicability and versatility. A spring with a buffer limiting effective stroke of L, a total compression of S, and a compression stiffness of K is specifically designed as an elastic element. These parameters match the axial load characteristics of various types of mechanical equipment, and can efficiently absorb and buffer axial impact energy. When subjected to impact load, the spring converts axial kinetic energy into elastic potential energy through elastic deformation, significantly weakening the impact force on the equipment component; when the load disappears, the spring elastically resets, avoiding rigid collision of components. This significantly reduces the risk of wear and fatigue damage to equipment components, effectively extending the service life of the limit switch itself and related equipment. This limit switch consists of only four core components: the outer shell 1, the inner shaft 2, two spring-loaded sliding collars 3, and the springs. It has no redundant or complex structures, fewer parts, and simpler assembly relationships, reducing manufacturing difficulty and production costs. Furthermore, each component adopts a modular design; the outer shell 1, inner shaft 2, spring-loaded sliding collars 3, and springs can all be independently machined, disassembled, and replaced. During later maintenance, it is not necessary to disassemble the entire equipment; only damaged parts need to be inspected or replaced individually, greatly simplifying the maintenance process, shortening downtime for maintenance, and reducing equipment operation and maintenance costs. The core components are made of suitable high-performance materials, combined with precise dimensional machining, ensuring that the spring-loaded sliding collars 3 can slide flexibly along the inner shaft 2, while also possessing radial and axial load-bearing capacity. This avoids problems such as movement jamming or insufficient load-bearing capacity, ensuring stable operation of the limit switch under long-term, high-frequency working conditions.

[0040] 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. An intermittent bi-directionally compressible axial limiter, characterized in that, The utility model relates to a kind of spring-loaded bearing, including outer shell, inner shaft, two spring force transmission sliding collar and elastic element; The outer shell is the tubular structure of two ends opening, the inner shaft is arranged in the outer shell, and the axial working space exists between the inner shaft and the outer shell, so that the inner shaft can move along the axial direction relative to the outer shell, and the limiting initial stroke of the axial working space is L;The outer shell is made of high-strength steel;The inner shaft is made of alloy steel with good wear resistance; Two spring force transmission sliding collars are sleeved on the inner shaft and located in the outer shell, and the spring force transmission sliding collar can slide along the outer shaft and the inner shaft and can bear radial and axial load;The spring force transmission sliding collar is made of copper alloy;The outer surface of the spring force transmission sliding collar is treated by surface treatment; The elastic element is a spring, and the spring is installed between the two spring force transmission sliding collars, and the two ends of the spring are respectively in contact with the corresponding spring force transmission sliding collar;The total compression amount of the spring is S, and the compression stiffness is K.

2. An intermittent bi-directionally compressible axial stop according to claim 1, wherein, The spring force transmission sliding collar has the function of double sliding bearing.

3. An intermittent bi-directionally compressible axial stop according to claim 1, wherein, The surface roughness and outer diameter size precision of the inner shaft meet the matching requirements of the spring force transmission sliding collar.

4. The intermittent bi-directionally compressible axial limiter of claim 1, wherein, The inner diameter size of the outer shell is accurately processed according to the outer diameter size of the inner shaft and the design gap.

5. A method of manufacturing an intermittent bi-directionally compressible axial stopper according to any one of claims 1-4, characterized in that, It includes the following steps: (1) component manufacturing: a. outer shell processing: high-strength steel is selected, and the outer shell is processed into a hollow tubular structure with two open ends by mechanical processing. The inner diameter size of the outer shell is accurately processed according to the outer diameter size of the inner shaft and the design gap; b. inner shaft processing: alloy steel material with good wear resistance is selected, and turning processing is performed according to the design size to ensure the outer diameter size precision and surface roughness of the inner shaft; c. spring force transmission sliding collar processing: copper alloy material is selected, and the collar inner hole is processed to match the size of the inner shaft by casting or mechanical processing. The outer surface of the collar is treated by surface treatment; d. spring preparation: according to the design requirements of total compression amount S and compression stiffness K, select appropriate spring steel wire, and make spring through winding and heat treatment process; (2) assembly process: a. two processed spring force transmission sliding collars are respectively sleeved on the processed inner shaft to ensure that the collars can freely slide along the inner shaft; b. the prepared spring is installed between the two spring force transmission sliding collars, and the two ends of the spring are respectively in contact with the corresponding collars; c. the inner shaft assembled with the spring force transmission sliding collar and the spring is assembled into the outer shell to ensure that the gap between the inner shaft and the outer shell is uniform, and the assembly is completed.

6. The method of claim 5, wherein the method further comprises: In step (1)a, the mechanical processing includes cutting, drilling and polishing processes.

7. The method of claim 5, wherein the method further comprises: In step (1)b, the turning processing further includes polishing treatment of the shaft surface.

8. The method of claim 5, wherein the method further comprises: In step (1)c, the surface treatment is hardening and polishing process treatment; The inner hole size tolerance of the spring force transmission sliding collar is controlled within the design threshold range.

9. The method of claim 5, wherein the method further comprises: In step (2)a, the surface of the center shaft and the inner hole of the collar are cleaned before the spring force transmission sliding collar is sleeved.

10. The method of claim 5, wherein the method further comprises: In step (2)c, the assembled inner shaft needs to be tested for axial mobility relative to the outer housing.

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