Inflatable shaft

Abstract

The utility model relates to an inflatable shaft which comprises a roller, an expansion piece, a key strip and an air tap, the roller is sleeved on the periphery of the expansion piece, the peripheral wall of the expansion piece communicated with the air tap has expansion or reset deformation quantity along the radial direction, the peripheral wall of the roller is provided with a plurality of through grooves penetrating through the side wall of the roller, and the through grooves extend along the axial direction of the roller. The key strip comprises a strip-shaped key body and a fixing base, the length of the key body is matched with that of the through groove, one face of the fixing base abuts against the peripheral wall of the expansion piece, and the other face of the fixing base is provided with a positioning protrusion protruding towards the side wall of the roller and detachably connected with the key body. And the key bars are driven by the expansion or reset deformation quantity of the expansion pieces to move in a reciprocating mode in the radial direction of the roller in the through grooves. Due to the fact that the positioning protrusions are embedded into the through grooves, operation can be conducted from the outside of the roller when the key body is installed or detached, and the installation or detachment efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of winding parts, in particular to an air shaft. Background Art

[0002] The inflatable shaft is a special winding and unwinding shaft, that is, the shaft whose surface can protrude after high-pressure inflation, and the shaft whose surface part retracts quickly after deflation is called an inflatable shaft. The inflatable shaft has a wide range of uses. Any machine with winding, unwinding, and slitting can be used with inflatable shafts, even including the light metal industry. For example, the inflatable shaft is mainly suitable for printing equipment such as: plate drying machine, flexographic printing machine, gravure machine, trademark printing machine, etc.; other machines include: coating machine, leather machine, shaping machine, embossing machine, slitting machine, die-cutting machine, rewinding machine, paper tube machine, bag making machine, laminating machine, film blowing machine, foaming machine, laminating machine, embossing machine, papermaking machine, non-woven machine, cloth inspection machine, hot stamping machine, battery equipment, etc.

[0003] Generally speaking, an inflatable shaft includes an inflatable shaft body, which includes a hollow shaft, an inflatable component located inside the shaft, and a strip expansion key that contacts the inflatable component and extends out of the shaft. By inflating the inflatable shaft, the expansion key can be extended and retracted, thereby quickly fixing and removing the winding core. However, the strip expansion key is fixedly connected with the mounting body placed inside the shaft and then integrally formed, which is not conducive to installing the strip expansion key in a thicker roller, resulting in insufficient support strength of the entire inflatable shaft, inconvenience in use, and reduced work efficiency. Utility Model Content

[0004] In order to solve the above technical problems, the utility model discloses an inflatable shaft, which includes a roller, an expansion member, a key strip and an air nozzle. The roller is sleeved on the outer periphery of the expansion member, and the air nozzle is close to the end of the roller and penetrates the peripheral wall of the roller to communicate with the expansion member to form a gas flow channel. The peripheral wall of the expansion member has an expansion or reset deformation along its radial direction through the input or output of gas. The peripheral wall of the roller is provided with a plurality of through grooves penetrating its side wall. The through grooves are extended along the axial direction of the roller. The plurality of through grooves are staggered and spaced around the peripheral wall of the roller. The key strip includes a strip-shaped key body and a fixing seat. The length of the key body is adapted to the length of the through groove. One side of the fixing seat abuts against the outer peripheral wall of the expansion member, and the other side has a positioning protrusion protruding toward the side wall of the roller and is detachably connected to the key body to form a protruding end of the key strip embedded in the through groove. The expansion or reset deformation of the expansion member drives the key strip to reciprocate in the through groove along the radial direction of the roller.

[0005] Specifically, a positioning groove and a positioning block that can slide together are respectively provided at the detachable connection between the positioning protrusion and the key body. The positioning groove is arranged along the length direction of the key body, and the length of the positioning groove is consistent with the length of the key body. The shape of the positioning block matches the shape of the positioning groove to form a snap-on sliding groove mechanism.

[0006] Specifically, the distance between the groove walls at the ends of the positioning groove is not equal to the distance between the groove walls in the middle of the positioning groove.

[0007] Specifically, a fixing hole is provided on the top surface of the protruding end of the key bar, and the fixing hole extends along the top of the protruding end toward its bottom, and a plug-in fixing column is provided in the fixing hole, and the key body is fixedly connected to the positioning protrusion through the fixing column.

[0008] Specifically, the abutting contact surface between the fixing seat and the expansion member is an arc-shaped contact surface with corresponding shapes, and both ends along the length direction of the positioning protrusion have extension parts of the arc-shaped surface.

[0009] Specifically, the length of the key body is smaller than the length of the through slot, and there is a gap between two ends of the key body and two ends of the through slot to form an installation space for the key body to move.

[0010] Specifically, the sum of the height of the positioning protrusion and the height of the key body is greater than the depth of the through groove.

[0011] Specifically, a plurality of through holes are provided at corresponding positions of the extension portion and the peripheral wall of the roller, the through holes penetrate the peripheral wall of the roller, a reset member is provided in the through holes, the reset member includes a plug and a spring, the plug is installed at the opening position of the through hole and seals the opening, and the two ends of the spring are respectively abutted against the bottom of the plug and the convex surface of the extension portion.

[0012] Specifically, the initial length of the spring is greater than the depth of the through hole.

[0013] Specifically, the contact surface between the extension portion and the spring is a smooth surface.

[0014] Advantages

[0015] The key strip in the utility model comprises a key body and a fixing seat, one side of the fixing seat abuts against the outer peripheral wall of the expansion piece, and the other side has a positioning protrusion protruding toward the side wall of the roller and is detachably connected to the key body, forming a protruding end of the key strip embedded in the through groove, and the key strip is driven to reciprocate in the radial direction of the roller in the through groove through the expansion or reset deformation of the expansion piece. Since the positioning protrusion of the fixing seat is embedded in the through groove, the key body can be installed or removed from the outside of the roller, thereby improving the installation or removal efficiency and conveniently and quickly replacing the key body. In addition, collision with the roller can be avoided during the removal process, thereby reducing maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic structural diagram of the key bar and the through groove of the pneumatic shaft of the utility model in the combined state;

[0017] Figure 2 It is a partial cross-sectional view of the key bar and the through groove of the utility model;

[0018] Figure 3 It is a structural schematic diagram of the key bar of the utility model;

[0019] Figure 4 It is a cross-sectional view of the key bar and roller of the utility model being embedded.

[0020] legend:

[0021] 1. Roller; 11. Through groove; 12. Through hole; 13. Air nozzle; 2. Key strip; 21. Key body; 211. Positioning block; 212. Fixing hole; 213. Bolt hole; 22. Fixing seat; 221. Extension part; 2211. Smooth surface; 222. Positioning protrusion; 2221. Positioning through groove; 3. Expansion piece; 4. Reset piece; 41. Plug; 42. Spring. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are preferred embodiments of the utility model and should not be regarded as excluding other embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0023] In the claims, specification and the above-mentioned drawings of the utility model, unless otherwise explicitly defined, directional words, such as the terms "center", "top", "bottom", "inside", "outside", "up", "down", "front", "back", etc., indicating directions or positional relationships are based on the directions and positional relationships shown in the drawings, and are only for the convenience of describing the utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction or be constructed and operated in a specific direction, and therefore cannot be understood as limiting the specific protection scope of the utility model.

[0024] In the claims, specification and drawings of the present utility model, if the terms "include", "have" and their variations are used, they are intended to mean "including but not limited to".

[0025] The present invention will be further described below in conjunction with the embodiments, but is not limited to the contents of the specification.

[0026] The utility model relates to an inflatable shaft, which comprises a roller 1, an expansion member 3, a key strip 2 and an air nozzle 13. The roller 1 is sleeved on the outer periphery of the expansion member 3. The air nozzle 13 is close to the end of the roller 1 and penetrates the peripheral wall of the roller 1 and is connected with the expansion member 3 to form a gas flow channel. The peripheral wall of the expansion member 3 has an expansion or reset deformation amount along its radial direction through the input or output of gas. The peripheral wall of the roller 1 is provided with a plurality of through grooves 11 penetrating its side wall. The through grooves 11 are extended along the axial direction of the roller 1. The plurality of through grooves 11 The key strip 2 is staggered and spaced around the peripheral wall of the roller 1, and includes a strip-shaped key body 21 and a fixing seat 22. The length of the key body 21 is adapted to the length of the through-slot 11. One side of the fixing seat 22 abuts against the outer peripheral wall of the expansion member 3, and the other side has a positioning protrusion 222 protruding toward the side wall of the roller 1 and is detachably connected to the key body 21, forming a protruding end of the key strip 2 embedded in the through-slot 11, and the key strip 2 is driven to reciprocate in the radial direction of the roller 1 in the through-slot 11 through the expansion or reset deformation of the expansion member 3.

[0027] During the installation process, the positioning protrusion 222 of the fixing seat 22 can be embedded into the position of the through groove 11. At this time, the positioning protrusion 222 has a guiding function, and the positioning protrusion 222 can be quickly positioned at the position of the through groove 11. Then, the expansion member 3 in the initial state is placed in the roller 1. The outside of the expansion member 3 is a rubber hose, and the inside is filled with an axle rod. At this time, an installation gap is formed between the outer peripheral wall of the expansion member 3 and the inner peripheral wall of the roller 1, which is convenient for adjusting the position of the expansion member 3, thereby ensuring that the expansion member 3 is coaxially arranged with the roller 1. In addition, during the installation of the expansion member 3, the air port of the expansion member 3 needs to be aligned with the roller 1. The air nozzle 13 of the quasi-roller 1 is positioned, and then the healthy body is installed on the top of the positioning protrusion 222 from the outer periphery of the roller 1 to form a key strip 2. At this time, the fixing seat 22 located at the bottom of the key strip 2 abuts against the outer wall of the expansion member 3. Further, when the expansion member 3 is in the initial state, the top of the key strip 2 is flush with the outer peripheral wall of the roller 1. After the expansion member 3 is ventilated and expanded, the top of the key strip 2 protrudes from the peripheral wall of the roller 1. Correspondingly, the inflatable shaft can lock external components, such as a round paper tube. When it is necessary to release the paper unloading, the air nozzle 13 is opened and the expansion member 3 is restored to its initial state, and the external component can slide out smoothly.

[0028] In addition, due to the detachable connection between the key body 21 and the fixing seat 22, the key body 21 can be installed from the outer periphery of the roller 1, without limiting the installation space, thereby improving the installation efficiency. The positioning protrusion 222 is embedded in the through groove 11, so that the key strip 2 of the present application can be applied not only to rollers 1 with thinner walls, but also to rollers 1 with thicker walls, while ensuring the support strength of the inflatable shaft, thereby improving the application range of the key strip 2.

[0029] Since the positioning protrusion 222 cooperates with the key body 21 and is embedded in the through groove 11, and after the key body 21 is embedded, the top of the key body 21 protrudes from the outer peripheral wall of the roller 1. At this time, the top of the key body 21 can form a supporting effect on the components outside the roller 1. Parallel reinforcing ribs are arranged on the top of the key body 21. The length of the reinforcing ribs is consistent with that of the key body 21, and the reinforcing ribs are protruded toward the external components. In this embodiment, the sum of the height of the positioning protrusion 222 and the height of the key body 21 is greater than the height of the through groove 11. Depth, at this time, the reinforcing ribs on the top of the key body 21 have friction in the circumferential direction when they abut against the components outside the roller 1, until the position of the expansion member 3 is adjusted to the optimal position, which can ensure that when the peripheral wall of the expansion member 3 expands in the installation gap, the radial movement distances of the multiple key strips 2 are equal, that is, the tops of the multiple key strips 2 can abut against the surface of the external component at the same time, thereby avoiding eccentricity of the key strip 2 during the rotation of the roller 1, and long-term rotation will also cause damage to part of the key strip 2, thereby increasing the service life of the key strip.

[0030] During use, the bottom of the positioning protrusion 222 is integrally formed with the bottom of the fixing seat 22, and the shape of the protruding end of the positioning protrusion 222 is similar to the shape of the key body 21, which is a long column, that is, the two end surfaces in the length direction of the positioning protrusion 222 are relatively set arc shapes, and the top surface of the positioning protrusion 222 is a flat surface and is set parallel along its length direction. On this basis, the key body 21 can be detachably fixed on the top of the positioning protrusion 222, and the bottom of the key body 21 is just overlapped on the top of the positioning protrusion 222 and fixed. At this time, the positioning protrusion 222 of the fixing seat 22 forms a support for the key body 21. Preferably, the length and width of the key body 21 are respectively the same as the length and width of the positioning protrusion 222.

[0031] Furthermore, a positioning groove 2221 and a positioning block 211 that can slide together are respectively provided at the detachable connection between the positioning protrusion 222 and the key body 21. The positioning groove 2221 is arranged along the length direction of the key body 21, and the length of the positioning groove 2221 is consistent with the length of the key body 21. The shape of the positioning block 211 matches the shape of the positioning groove 2221 to form a snap-on sliding groove mechanism.

[0032] That is to say, the positioning groove 2221 is arranged on the top surface of the positioning protrusion 222, and the positioning groove 2221 is recessed toward the bottom direction of the fixing seat 22, and the groove wall of the positioning groove 2221 has a certain thickness. Correspondingly, the positioning block 211 is protruded toward the positioning groove 2221, and the positioning block 211 can be inserted into the positioning groove 2221, and the height of the positioning block 211 is equal to the depth of the positioning groove 2221. In this way, when the inflatable shaft rotates around its axis, the top of the key body 21 is prevented from being subjected to the friction force in the circumferential direction, and the positioning block 211 is squeezed and contacted with the groove wall of the positioning groove 2221 to damage the groove wall, thereby ensuring the stability of the key body 21 and the fixing seat 22.

[0033] Furthermore, since the key body 21 and the positioning protrusion 222 are matched with a snap-fitting slide groove, the positioning groove 2221 at this time has a quick positioning effect, so that the positioning block 211 can be quickly snapped into the positioning groove 2221, so that the bottom surface of the key body 21 is completely in contact with the top surface of the positioning protrusion 222.

[0034] The distance between the groove walls at the ends of the positioning groove 2221 is not equal to the distance between the two groove walls in the middle of the positioning groove 2221. In this embodiment, the distance between the groove walls in the middle of the positioning groove 2221 is smaller than the distance between the groove walls at the two ends of the positioning groove 2221, and the distance between the two groove walls gradually increases from the middle to the two ends. At this time, the shape of the positioning groove 2221 is similar to a gourd shape with equal sizes at both ends. Correspondingly, the key body 21 has no direction when it is installed. Only when the key body 21 is subjected to the sliding force in the axial direction, the groove wall in the middle of the positioning groove 2221 of the positioning protrusion 222 will prevent the key body 21 from sliding back and forth along its length direction, avoiding the key body 21 from being damaged by the end of the key body 21 pressing against the end of the through groove 11 due to sliding, thereby forming a certain protective effect on the key body 21 and improving the service life of the key body 21.

[0035] A fixing hole 212 is provided on the top surface of the protruding end of the key bar 2. The fixing hole 212 extends from the top of the protruding end toward the bottom thereof. A plug-in fixing column is provided in the fixing hole 212. The key body 21 is fixedly connected to the positioning protrusion 222 via the fixing column.

[0036] It should be noted that the fixing holes 212 are arranged at both ends of the positioning protrusion 222, that is, there are two fixing holes 212, and the distances between the two fixing holes 212 and the ends of the key body 21 are equal. This ensures that after the fixing column cooperates with the fixing hole 212, the tightening force on the key body 21 is evenly set to avoid different heights at the two ends of the key body 21. At this time, only the end of the key body 21 with a higher height is in a locked state with the external components, thereby reducing the locking effect.

[0037] In addition, in order to firmly install the key body 21 on the top of the positioning protrusion 222, the diameter of the fixing hole 212 can be further limited. In this embodiment, the fixing hole 212 is a variable diameter structure along the height direction, that is, the upper part of the fixing hole 212 is a large-diameter cylinder, and the lower part of the fixing hole 212 is a small-diameter cylinder. The depth of the upper part of the fixing hole 212 is less than the height of the key body 21, and the lower part of the fixing hole 212 is from the bottom of the positioning groove 2221 of the positioning protrusion 222. Preferably, the diameter of the lower part of the fixing hole 212 is slightly smaller than the distance between the groove walls at both ends. Correspondingly, the shape of the fixing column is adapted to the shape of the fixing hole 212, so that it can be ensured that after the fixing column is matched with the fixing hole 212, the top of the fixing column is at most flush with the top of the key strip 2, and the bottom of the fixing column extends along the fixing hole 212 into the interior of the positioning protrusion 222, thereby ensuring that the key body 21 can be firmly fixed on the top of the positioning protrusion 222.

[0038] The centers of the two fixing holes 212 are both distributed on the center line of the key bar 2. At this time, the center line of the key bar 2 divides the key bar 2 into two equal parts. That is to say, the hole diameter of the fixing hole 212 is smaller than the width of the key bar 2. An anti-slip groove is arranged on the peripheral side of the fixing hole 212. The anti-slip groove extends along the length direction of the key bar 2, and the length of the anti-slip groove is equal to the length of the key body 21.

[0039] For the convenience of fixation, an internal thread is provided on the inner side wall of the small diameter hole at the lower part of the fixing hole 212, and correspondingly, an external thread is provided on the peripheral wall of the fixing column. Through the screw connection between the internal thread and the external thread, the key body 21 can be quickly and detachably fixed to the top of the fixing seat 22, and during the fixing process, the fixing column will not affect the groove wall of the positioning groove 2221, further ensuring that the key body 21 is stably fixed to the top of the fixing seat 22.

[0040] The contact surface between the fixing seat 22 and the expansion member 3 is an arc-shaped contact surface with corresponding shapes, and both ends of the positioning protrusion 222 along the length direction have arc-shaped extension portions 221 .

[0041] In this embodiment, the extension portion 221 is formed by extending outward along the length direction of the positioning protrusion 222, and the top of the extension portion 221 can abut against the inner wall of the roller 1, so that the contact area between the top surface of the extension portion 221 and the inner circumferential wall of the roller 1 can be increased, thereby increasing the friction between the extension portion 221 and the side wall of the roller 1, so that the extension portion 221 cooperates with the positioning protrusion 222 to prevent the positioning protrusion 222 from rotating in the through groove 11 along the circumferential direction of the roller 1, and the shape of the bottom of the limiting portion is also compatible with the shape of the circumferential wall of the hose of the expansion member 3, which also increases the contact area between the limiting portion and the hose, and can also improve the friction between the limiting portion and the hose in the circumferential direction, ensuring that the fixed seat 22 of the inflatable shaft stably abuts against the circumferential wall of the hose during the expansion process, and ensuring the stability of the key strip 2 during the expansion or resetting process of the inflatable shaft.

[0042] Furthermore, arc-shaped flanges are respectively provided on both sides along the length direction of the fixing seat 22, and the arc-shaped flanges are connected to one side of the extension portion 221 to form a whole. After installation, the top and bottom of the arc-shaped flanges can also abut against the inner circumferential wall of the roller 1 and the outer circumferential wall of the hose, so that the fixing seat 22 of the key strip 2 can be better prevented from sliding along the circumferential direction and axial direction of the hose during the expansion process. Moreover, since the arc-shaped flanges are provided on the left and right sides of the positioning protrusion 222, and the arc-shaped flanges and the positioning protrusion 222 are integrally formed, at this time, the arc-shaped flanges and the positioning protrusion 222 jointly support the key body 21, which can further prevent the key body 21 from falling off from the through groove 11.

[0043] Alternatively, a bolt hole 213 is further provided at the midpoint of the line connecting the two fixing holes 212, and the depth of the bolt hole 213 is equal to the height of the key body 21. During the maintenance process, an external bolt is inserted into the bolt hole 213 of each key bar 2. At this time, the external bolt can form a certain limiting effect on the key body 21, and then the expansion piece 3 is pulled out of the roller 1. The key bar 2 can still maintain its initial state before maintenance, which can further prevent the key bar 2 from slipping out of the through groove 11 and avoid damage to the key bar 2 during the maintenance process.

[0044] The length of the key body 21 is smaller than the length of the through slot 11, and there is a gap between the two ends of the key body 21 and the two ends of the through slot 11 to form an installation space for the key body 21 to move. In this way, the key body 21 can be quickly installed in the through slot 11, and the collision and damage of the key body 21 with the side wall of the through slot 11 during the installation process can be avoided, thereby improving the installation and disassembly efficiency, and also avoiding affecting the normal use of the air shaft, thereby increasing the service life of the key strip 2.

[0045] A plurality of through holes 12 are provided at corresponding positions between the extension portion 221 and the peripheral wall of the roller 12. The through holes 12 penetrate the peripheral wall of the roller 12. A reset member 4 is provided in the through hole 12. The reset member 4 includes a plug 41 and a spring 42. The plug 41 is installed at the opening position of the through hole 12 and seals the opening. Both ends of the spring 42 are respectively in contact with the bottom of the plug 41 and the convex surface of the extension portion 221.

[0046] A through hole 12 is provided at both ends of the length direction of each key body 21, the connecting line of the two through holes 12 coincides with the center line of the through slot 11, and the distance between each through hole 12 and the corresponding end of the through slot 11 is equal, and a reset member 4 is installed in each through hole 12, so as to ensure that the reset member 4 has equal force on the extension portion 221 of the fixing seat 22, thereby ensuring that the deformation amount that can be restored at both ends of the key strip 2 is equal.

[0047] In order to enable the reset member 4 to automatically restore to its initial state when the air nozzle 13 is opened, the reset member 4 includes a plug 41 arranged at the outer port of the through hole 12. At this time, the outer port is a port close to the outer peripheral wall of the roller 1, and a thread is arranged on the peripheral wall of the plug 41. Correspondingly, an internal thread matching the plug 41 is arranged on the upper part of the through hole 12, which can be selected by screwing the plug 41 in and out. The lower end of the plug 41 abuts against the spring 42, and the bottom end of the spring 42 abuts against the position of the extension part 221. When the expansion member 3 expands in the radial direction, the extension part 221 compresses the spring 42. At this time, the plug 41 forms a supporting effect on the spring 42, so that the spring 42 has elastic potential energy in the inward direction, that is, opposite to the expansion direction of the expansion member 3.

[0048] In order to reduce the torque of the spring 42 itself, a limiting ridge is provided at the contact position between the plug 41 and the spring 42. The limiting ridge protrudes downward in the direction of the extension portion 221, and the diameter of the limiting ridge is smaller than the inner diameter of the spring 42. In this way, the spring 42 can be sleeved on the outer peripheral wall of the limiting ridge, which can prevent the end of the spring 42 from shifting during the compression process. This will cause a certain loss of elastic potential energy of the spring 42, thereby slowing down the recovery efficiency of the expansion member 3.

[0049] The initial length of the spring 42 is greater than the depth of the through hole 12. That is to say, after the reset member 4 is installed in the through hole 12, after the air nozzle 13 of the expansion member 3 is opened, the expansion deformation of the hose gradually decreases until it returns to the initial state, and the spring 42 is in a compressed state. At this time, the elastic potential energy of the spring 42 can be converted into a compressive force on the outer wall of the hose, so that the expansion member 3 can be quickly restored to the initial state. In addition, the spring 42 is close to both ends of the fixing seat 22, and the distance between the two springs 42 is greater than the length of the key body 21, so that the expansion member 3 can be quickly restored to the initial state with a smaller elastic potential energy, thereby improving the recovery efficiency.

[0050] The contact surface between the extension part 221 and the spring 42 is a smooth surface 2211. The smooth surface 2211 can be formed by cutting at a later stage, and the surface area of ​​the smooth surface 2211 can be slightly larger than the diameter of the through hole 12, or the entire arc-shaped top surface of the extension part 221 can be set as the smooth surface 2211, and when the spring 42 contacts the smooth surface 2211, the friction force generated between the end of the spring 42 and the smooth surface 2211 is reduced, ensuring that the pressure of the spring 42 during the extrusion or reset process is always set perpendicular to the smooth surface 2211 of the extension part 221.

[0051] Obviously, the above-mentioned embodiments of the present invention are merely examples for clearly explaining the present invention, and are not intended to limit the embodiments of the present invention. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the embodiments here. All obvious changes or modifications derived from the technical solution of the present invention are still within the scope of protection of the present invention.

Claims

1. An inflatable shaft, characterized in that: It comprises a roller (1), an expansion member (4), a key bar (2) and a gas nozzle (13); the roller (1) is sleeved on the outer periphery of the expansion member (4); the gas nozzle (13) is close to the end of the roller (1) and penetrates the peripheral wall of the roller (1) to communicate with the expansion member (4) to form a gas flow channel; through the input or output of gas, the peripheral wall of the expansion member (4) has an expansion or reset deformation along its radial direction; the peripheral wall of the roller (1) is provided with a plurality of through grooves (11) penetrating its side wall; the through grooves (11) are extended along the axial direction of the roller (1); and the plurality of through grooves (11) surround the roller (1). ) are arranged in an interlaced and spaced relationship on the peripheral wall, the key strip (2) comprises a strip-shaped key body (21) and a fixing seat (22), the length of the key body (21) is adapted to the length of the through groove (11), one side of the fixing seat (22) abuts against the outer peripheral wall of the expansion member (4), and the other side has a positioning protrusion (222) protruding toward the side wall of the roller (1) and is detachably connected to the key body (21), forming a protruding end of the key strip embedded in the through groove (11), and the key strip (2) is driven to move back and forth in the radial direction of the roller (1) in the through groove (11) by the expansion or reset deformation of the expansion member (4).

2. The inflatable shaft according to claim 1, characterized in that: A slidably matched positioning groove (2221) and a positioning block (211) are respectively provided at the detachable connection between the positioning protrusion (222) and the key body (21); the positioning groove (2221) is provided along the length direction of the key body, and the length of the positioning groove (2221) is consistent with the length of the key body (21); the shape of the positioning block (211) matches the shape of the positioning groove (2221), so as to form a snap-fitting slide groove mechanism.

3. The inflatable shaft according to claim 2, characterized in that: The distance between the groove walls at the ends of the positioning groove (2221) is not equal to the distance between the groove walls in the middle of the positioning groove.

4. The inflatable shaft according to claim 3, characterized in that: A fixing hole (212) is provided on the top surface of the protruding end of the key bar (2), the fixing hole (212) is extended from the top of the protruding end toward the bottom thereof, and a plug-in fixing column is provided in the fixing hole (212), and the key body (21) is fixedly connected to the positioning protrusion (222) via the fixing column.

5. The inflatable shaft according to claim 2, characterized in that: The abutting contact surfaces of the fixing seat (22) and the expansion member (4) are arc-shaped contact surfaces of corresponding shapes, and arc-shaped extension portions (221) are provided at both ends along the length direction of the positioning protrusion (222).

6. The inflatable shaft according to claim 3, characterized in that: The length of the key body (21) is smaller than the length of the through slot (11), and there is a gap between the two ends of the key body (21) and the two ends of the through slot (11) to form an installation space for the key body (21) to move.

7. The inflatable shaft according to claim 4, characterized in that: The sum of the height of the positioning protrusion (222) and the height of the key body (21) is greater than the depth of the through groove (11).

8. The inflatable shaft according to claim 5, characterized in that: A plurality of through holes (12) are provided at corresponding positions of the extension portion (221) and the peripheral wall of the roller (1); the through holes (12) penetrate the peripheral wall of the roller (1); a reset member (5) is provided in the through holes (12); the reset member (5) comprises a plug (51) and a spring (52); the plug (51) is installed at the opening position of the through hole (12) and blocks the opening; two ends of the spring (52) are respectively in contact with the bottom of the plug (51) and the convex surface of the extension portion (221).

9. The inflatable shaft according to claim 8, characterized in that: The initial length of the spring (52) is greater than the depth of the through hole (12).

10. The inflatable shaft according to claim 8, characterized in that: The contact surface between the extension portion (221) and the spring (52) is a smooth surface (2211).

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