A rotary damping mechanism

Abstract

The present invention discloses a rotary damping mechanism, comprising: a sleeve with a shaft cavity filled with damping oil, a rotating shaft with an inner shaft section in sealed rotational fit with the shaft cavity, and a gland for sealing the opening of the sleeve. The mechanism further includes: a piston rotatably mounted in the shaft cavity and cooperating with the rotating shaft, a clearance formed by the cooperation between the piston and the shaft cavity wall to form an outer oil passage of the piston, and a clearance formed by the cooperation between a threaded hole and an outer threaded shaft section to form an inner oil passage of the piston; a plug ring capable of axially moving is arranged at the end of the piston close to the outer shaft section of the rotating shaft, and the plug ring, the piston and the shaft cavity wall cooperate to form a one-way valve for switching the outer oil passage, and an opening valve for switching the inner oil passage is formed by the cooperation between an inner circular hole and a gradient circular shaft section; when the rotating shaft actuates the piston to move to a position where both the one-way valve and the opening valve are closed, the damping oil slowly percolates through the outer oil passage and / or the inner oil passage, and the oil pressure difference between both ends of the piston in the shaft cavity slowly decays, and the decayed oil pressure brakes the slow movement of the piston to make the rotating shaft rotate slowly.

Description

Technical Field

[0001] The present invention relates to a toilet cover assembly, in particular to a rotary damping mechanism. Background Art

[0002] The basic principle of the slow-fall damping of a toilet cover is hydraulic slow-down. By arranging buffer blades inside the bushing, the buffer blades carry a one-way valve mechanism to rotate inside the bushing to generate hydraulic torque output.

[0003] In the prior art, vane-type dampers are mostly used. The vane-type dampers adopt a radial oil-stirring method. Due to the large gaps between the vanes in the radial oil-stirring method, a large amount of damping oil needs to be filled. When in use, the strong oil pressure will make the rotating shaft become relatively fragile. It may have a slight advantage when applied to light covers and medium covers, but when applied to heavy covers, the small-diameter rotating shaft is difficult to bear, and dimensional changes are likely to occur during long-term use or due to thermal expansion and contraction with the change of seasons, thus affecting the damping effect.

[0004] For example, the existing Chinese patent number is: CN207253296U, and the patent name is: A slow-fall damper for a toilet cover, which includes a bushing that can be filled with damping oil, a rotating shaft that is hermetically and rotationally matched with the bushing to disturb the flow of damping oil, and two one-way valve plates. The inner cavity wall of the bushing has longitudinally arranged oil separation ribs. The rotating shaft includes a shaft core and two rotors oppositely arranged relative to the shaft core, and a symmetrically radially tapered arc surface is formed between the two rotors. A one-way valve plate is sleeved on each of the two rotors of the rotating shaft and is slidably matched with the inner cavity wall of the bushing. Symmetrically arranged oil passing grooves are respectively provided between the two oil separation ribs at the bottom of the inner cavity of the bushing and on the end surface where the rotating shaft is matched with the bushing. The lower end of the shaft core is rotationally matched with the center of the bottom of the inner cavity of the bushing. The integrity of the two rotors on the shaft core of the rotating shaft is relatively good, so that the structural features of the rotating shaft can be simplified, the processing difficulty of the rotating shaft can be reduced, and the one-way valve plate swings relative to the rotor of the rotating shaft, and the bearing strength of the rotating shaft is strong. However, it has relatively high requirements for the dimensions of the entire inner cavity wall of the bushing and the one-way valve, and the tolerances that can be tolerated in dimensions are small. Precision deviation during processing or cavity deformation after long-term use will cause the tolerance to become larger. Once the tolerance is too large, it is easy to have a slower oil return speed, the entire cover gets stuck in the middle, or the oil return speed is too fast, and the entire cover quickly flips down and makes noise. Summary of the Invention

[0005] The present invention provides a rotary damping mechanism, which can effectively solve the above problems.

[0006] The present invention is implemented as follows:

[0007] A rotary damping mechanism includes: a bushing with a shaft cavity filled with damping oil, a rotating shaft with an inner shaft section hermetically and rotationally matched with the shaft cavity, a gland for sealing the opening of the bushing, and further includes:

[0008] A piston that is fixedly installed in the shaft cavity and cooperates with the rotating shaft. The piston includes a central hole opened axially, and the central hole is composed of a threaded hole and an inner circular hole. The inner shaft section includes an external threaded shaft section and a gradient circular shaft section. The external threaded shaft section is screwed into the threaded hole so that the rotating shaft can actuate the piston to reciprocate axially in the shaft cavity to flex and press the damping oil.

[0009] The interval between the piston and the shaft cavity wall forms the external oil passage of the piston, and the clearance between the threaded hole and the external threaded shaft section forms the internal oil passage of the piston.

[0010] A plug ring that can move axially is installed on the end of the piston close to the outer shaft section of the rotating shaft. A strain gap is opened radially on the plug ring, and the strain gap provides strain space for the radial expansion or contraction of the plug ring. The plug ring, the piston, and the shaft cavity wall cooperate to form a one-way valve for switching the external oil passage, and the inner circular hole and the gradient circular shaft section cooperate to form an opening valve for switching the internal oil passage.

[0011] When the rotating shaft actuates the piston to move until both the one-way valve and the opening valve are closed, the damping oil slowly seeps through the external oil passage and / or the internal oil passage, and the oil pressure difference between the two ends of the piston in the shaft cavity slowly decays. The decaying oil pressure brakes the slow movement of the piston, causing the rotating shaft to rotate slowly.

[0012] As a further improvement, the piston includes a cylindrical plug body that axially moves inward in the shaft cavity, and a convex edge that extends from the cylindrical plug body toward the end close to the outer shaft section of the rotating shaft. The plug ring reciprocates between the outer ring surface of the cylindrical plug body close to the outer shaft section of the rotating shaft and the convex edge.

[0013] As a further improvement, the cylindrical plug body includes a plurality of guiding grooves opened radially. A plurality of guiding ribs corresponding to and cooperating with the guiding grooves are fixedly connected to the inner wall of the shaft cavity. One end of the guiding groove close to the inner circular hole is open, and the end far from the inner circular hole is closed.

[0014] As a further improvement, the cylindrical plug body further includes a plurality of external oil passages opened radially. The external oil passages and the guiding grooves are arranged at intervals and staggered. Both ends of the external oil passage are open. When the plug ring presses against the external oil outlet of the external oil passage, the external oil passage is closed and the damping oil flows into the external threaded shaft section. When the plug ring moves away from the external oil outlet of the external oil passage, the external oil passage is opened and the damping oil moves along the external oil passage toward the side close to the gland.

[0015] As a further improvement, the plug ring includes a circular ring sleeved between the cylindrical plug body and the convex edge. The circular ring includes a plurality of limiting convex parts arranged on its inner ring surface at equal intervals and evenly distributed, and oil passing concave parts opened in the gaps between the limiting convex parts. The positions of the limiting convex parts correspond to those of the outer oil passing ports, and the limiting convex parts abut against the outer oil passing ports or the convex edge as the plug ring moves.

[0016] As a further improvement, a uniform expanding ring conical surface is connected to one side of the circular ring close to the gland. After the strain gap is affected by the damping oil pressure, the expanding ring conical surface will be expanded in diameter and abut against the inner wall of the shaft cavity.

[0017] As a further improvement, a uniform shrinking ring conical surface is connected to one side of the circular ring far from the gland. The damping oil entering from the outer oil passing port will compress the shrinking ring conical surface inward, so that the strain gap is compressed in diameter and separated from the inner wall of the shaft cavity, enabling the damping oil to pass quickly.

[0018] As a further improvement, the gradient circular shaft section includes a closed diameter, a gradually changing diameter, and an opening diameter connected in sequence along the extending direction of the outer screw shaft section. When the piston moves in the direction close to the gland side, the opening diameter, the gradually changing diameter, and the closed diameter are sequentially matched with the inner circular hole.

[0019] As a further improvement, the gradient circular shaft section is a mating shaft connected to the outer screw shaft section. The head and tail of the mating shaft have the same diameter. The mating shaft includes a large diameter part connected to the outer screw shaft section, a gradually changing groove arranged on the side of the large diameter part far from the gland and with the groove width gradually increasing, and a small diameter groove communicating with the gradually changing groove and with the groove width less than or equal to the diameter length of the end section of the gradually changing groove.

[0020] The beneficial effects of the present invention are as follows:

[0021] The present invention changes the commonly used vane type rotating shaft in the industry and introduces a brand-new threaded rotating shaft. Through the cooperation of the spiral rotating shaft and the piston with a threaded hole, the torque that the rotating shaft can bear is increased. Moreover, the internal space of the threaded fit is small, and the amount of damping oil filled is also reduced. Even when applied to a heavy cover plate, it can withstand great torsion and is not easily deformed to cause tolerances after long-term use.

[0022] Then, through the two-phase cooperation of the one-way valve composed of the plug ring and the piston and the opening degree valve composed of the piston and the gradient circular shaft section, when opening the cover plate, the plug ring can be retracted to achieve unobstructed opening of the cover, and when closing the cover plate, the plug ring can be expanded outward to abut against the shaft cavity of the shaft sleeve, and the damping oil flows back through the internal space of the piston. With the gradual change of the opening degree valve, the effects of rapid descent in the early stage, deceleration in the middle stage, and stable descent in the later stage are achieved, which can slow down the descent of the cover plate while increasing the closing speed of the cover plate.

[0023] And because of the one-way valve composed of the plug ring and the piston, the plug ring will expand outwards and abut against the shaft cavity after closing the external oil channel. The outward expansion action of the plug ring can compensate for the inner diameter tolerance of the shaft cavity. Even if the shaft cavity is deformed during the processing stage or after long-term use and has dimensional tolerance errors, it can be compensated by the outward expansion of the plug ring. The accuracy requirements for the shaft cavity are not high, and the requirements for both factory requirements and use environment are reduced, which is easy to promote.

[0024] When the one-way valve and the opening valve close the inner and outer oil passages, the hydraulic damping decays to cause the piston to move slowly toward the pressure cover, that is, the piston moves toward the cover plate support point, so that the cover plate is not prone to shaking when it slowly falls. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 It is a three-dimensional structural schematic diagram of a rotary damping mechanism provided by the present invention.

[0027] Figure 2 It is an exploded view (first perspective) of a rotary damping mechanism provided by the present invention.

[0028] Figure 3 It is an exploded view (second viewing angle) of a rotary damping mechanism provided by the present invention.

[0029] Figure 4 It is a structural schematic diagram of a plug ring provided by the present invention.

[0030] Figure 5 It is a structural schematic diagram of a piston provided by the present invention.

[0031] Figure 6 It is a structural schematic diagram of a rotating shaft provided by the present invention.

[0032] Figure 7 It is a front view structural schematic diagram of a rotary damping mechanism provided by the present invention.

[0033] Figure 8 The present invention Figure 7 Cross-sectional view at AA in the middle.

[0034] Figure 9 The present invention Figure 7 Cross-sectional view at the middle BB.

[0035] Figure 10 is a cross-sectional view of the present invention Figure 9 at C-C (when the cover plate is in the falling state and in the stage of the opening diameter cooperating with the inner round hole).

[0036] Figure 11 is a cross-sectional view of the present invention Figure 9 at C-C (when the cover plate is in the falling state and in the stage of the tapered diameter cooperating with the inner round hole).

[0037] Figure 12 is a cross-sectional view of the present invention Figure 9 at C-C (when the cover plate is in the falling state and in the stage of the closing diameter cooperating with the inner round hole).

[0038] Figure 13 is a cross-sectional view of the present invention Figure 9 at C-C (when the cover plate is in the open state).

[0039] Figure 14 is a cross-sectional view of a rotating shaft provided by another embodiment of the present invention

[0040] Reference numerals:

[0041] Bushing - 1; Shaft cavity - 10; Guide rib - 101;

[0042] Rotating shaft - 2; Inner shaft section - 20; Outer threaded shaft section - 21; Tapered circular shaft section - 22;

[0043] Closing diameter - 221; Tapered diameter - 222; Opening diameter - 223;

[0044] Large diameter part - 227; Tapered groove - 228; Small diameter groove - 229;

[0045] Piston - 3; Central hole - 30; Threaded hole - 301; Inner round hole - 302;

[0046] Cylindrical plug body - 31; Guide groove - 311; Flange - 32;

[0047] Outer oil passage - 3a; Outer oil port - 3a1; Inner oil passage - 3b;

[0048] Plug ring - 4; Strain gap - 40; Circular ring - 41; Limit convex part - 411;

[0049] Oil recess - 412; Expansion ring cone surface - 42; Contraction ring cone surface - 43;

[0050] Gland - 5; End cover - 51; Gasket - 52; Sealing ring - 53;

[0051] One-way valve - Q; Opening valve - Z. Detailed implementation manners

[0052] To make the embodiments of the present invention, all fall within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the scope of protection of the present invention.

[0053] In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "a plurality" means two or more unless otherwise specifically defined.

[0054] Refer to Figures 1-14 As shown, a rotary damping mechanism includes: a shaft sleeve 1 filled with damping oil in a shaft cavity 10, a rotating shaft 2 with an inner shaft section 20 in sealed rotational fit with the shaft cavity 10, a gland 5 sealing the opening of the shaft sleeve 1, and further includes: a piston 3 rotatably mounted in the shaft cavity 10 and cooperating with the rotating shaft 2, the piston 3 including a central hole 30 axially formed, the central hole 30 being composed of a threaded hole 301 and an inner circular hole 302, the inner shaft section 20 including an external threaded shaft section 21 and a gradient circular shaft section 22, the external threaded shaft section 21 being screwed into the threaded hole 301 so that the rotating shaft 2 can actuate the piston 3 to reciprocate axially in the shaft cavity 10 to flex the damping oil;

[0055] Such as Figures 7-12As shown, the clearance between the piston 3 and the wall of the shaft cavity 10 forms an external oil passage 3a of the piston 3, and the clearance between the threaded hole 301 and the external threaded shaft section 21 forms an internal oil passage 3b of the piston 3; on the end of the piston 3 close to the outer shaft section of the rotating shaft 2, a plug ring 4 that can move axially is installed. The plug ring 4, the piston 3 and the wall of the shaft cavity 10 cooperate to form a one-way valve Q for switching the external oil passage 3a, and the inner circular hole 302 and the gradient circular shaft section 22 cooperate to form an opening valve Z for switching the internal oil passage 3b; when the rotating shaft 2 actuates the piston 3 to move to a position where both the one-way valve Q and the opening valve Z are closed, the damping oil slowly seeps through the external oil passage 3a and / or the internal oil passage 3b, and the oil pressure difference between the two ends of the piston 3 in the shaft cavity 10 slowly decays. The decaying oil pressure brakes the slow movement of the piston 3, causing the rotating shaft 2 to rotate slowly.

[0056] Referring to Figure 1 , Figure 7 and Figure 8 , in the application of slow-falling damping, damping oil needs to be filled in the shaft sleeve 1. To avoid leakage of the damping oil, a gland 5 needs to be welded to the shaft sleeve 1, so that there will be no oil leakage during the cooperation of the rotating shaft 2 with the shaft sleeve 1 and its internal structure. During the sealing of the gland, since there is still air in the shaft sleeve when the gland is pressed in, if it is directly welded, noise will occur in the shaft sleeve when the rotating shaft rotates. Therefore, the gland 5 in this embodiment includes an end cover 51, a gasket 52 and a sealing ring 53. Outside the rotating shaft 2, the gasket 52 is placed on the rotating shaft 2, the sealing ring 53 is sleeved on the rotating shaft 2, and the end cover 51 is pressed into the shaft sleeve 1 to form a seal between the sealing ring 53 and the rotating shaft 2. The air in the shaft cavity 10 is discharged from the gap between the inner wall of the shaft sleeve 1 and the circumferential wall of the end cover 51, and then the end cover 51 and the shaft sleeve 1 are welded and sealed by wave soldering, so that the inner shaft section 20 on the rotating shaft 2 can be sealed in the shaft cavity 10 filled with damping oil, and at the same time, all the air inside the shaft cavity 10 is completely discharged, and there is no noise when it is in use.

[0057] Referring to Figures 2-3 and Figure 8 , the rotating shaft 2 does not move axially throughout the process, but only rotates radially. The rotating shaft 2 includes a conventional shaft handle section on the outside and an inner shaft section 20. Among them, the shaft handle section cooperates with the cover plate or the seat ring to achieve slow descent, while the inner shaft section 20 does not adopt the existing vane type structure, but adopts a spiral design. The inner shaft section 20 is divided into an external threaded shaft section 21 and a gradient circular shaft section 22 that cooperate with two parts of the piston 3. By cooperating the external threaded shaft section 21 with the piston 3, the cooperation effect between the rotating shaft 2 and the piston 3 is enhanced. Compared with the way of radially agitating the damping oil by vanes, in this embodiment, the piston 3 axially agitates the damping oil in the shaft sleeve 1, making the torque of the rotating shaft 2 stronger, and both light cover plates and heavy cover plates can be stably carried.

[0058] The movement mode of the piston 3 cooperating with the rotating shaft 2 is different from that of the rotating shaft 2. The piston 3 only moves axially and does not rotate within the bearing sleeve 1. A central hole 30 is axially formed in the piston 3. The central hole 30 includes a threaded hole 301 that cooperates with the external threaded shaft section 21. The threaded hole 301 cooperates with the external threaded shaft section 21 so that when the external threaded shaft section 21 rotates, the entire piston 3 moves axially. The central hole 30 further includes an inner circular hole 302, and the inner circular hole 302 is directly communicated with the shaft cavity 10 within the bearing sleeve 1, and can serve as a channel for the damping oil to flow back to its original position during the oil return process.

[0059] Referring to Figures 2-3 and Figure 8 , a plug ring 4 is also sleeved on the piston 3, and the position of the plug ring 4 will change with the movement of the damping oil and the piston 3;

[0060] There are two oil circuits in the entire damping mechanism. One is the oil inlet circuit, and the other is the oil return circuit. The oil inlet uses the outer oil passage 3a formed by the gap between the piston 3 and the wall of the shaft cavity 10, and the oil return uses the inner oil passage 3b formed by the gap between the threaded hole 301 and the external threaded shaft section 21;

[0061] When the user needs to lift the cover plate, at this time, the damping oil moves towards the direction close to the gland 5 through the outer oil passage 3a. The gradually introduced damping oil pushes the piston 3 towards the side away from the gland 5. At the same time, the damping oil presses on the outer ring surface of the plug ring 4, pressing the plug ring 4 inward. The one-way valve Q formed by the cooperation of the plug ring 4, the piston 3, and the wall of the shaft cavity 10 is opened for rapid oil passage. There is no oil pressure difference at both ends of the piston 3. Since there is no damping oil pressure acting on the piston 3, the rotating shaft 2 can quickly drive the piston 3 to move axially quickly, that is, the rotating shaft 2 can rotate quickly, and the user can easily lift the cover plate. When the cover plate is lifted too fast, at this time, the damping oil is too late to pass through the plug ring 4, and the rapid damping oil will squeeze the outer ring surface of the plug ring 4, causing the plug ring 4 to contract and form a gap with the wall of the shaft cavity 10 to allow the damping oil to pass through quickly;

[0062] When the user flips down the cover plate, at this time, the damping oil wants to flow back through the outer oil passage 3a. However, during this process, the damping oil will first push the plug ring 4 towards the piston 3, and the plug ring 4 will block the outer oil passage 3a of the piston 3, that is, the one-way valve Q closes, and the outer oil passage 3a is blocked. At the same time, since the damping oil cannot flow back through the outer oil passage 3a, the continuously introduced damping oil will increase in pressure, which will expand the plug ring 4 outward, and the rotating shaft 2 and the piston 3 can no longer move relative to each other. As a result, the damping oil can only flow back through the inner oil passage 3b. Once the damping oil starts to flow back, the pressure of the plug ring 4 gradually decreases, the rotating shaft 2 and the piston 3 return to the moving state, and the cover plate falls under the action of gravity. As the cooperation between the gradient circular shaft section 22 of the rotating shaft 2 and the inner circular hole 302 makes the opening of the opening valve Z gradually smaller, the piston 3 causes a throttling effect on the opening valve Z during the moving process, changing the oil pressure at both ends of the piston 3, which can make the initial downward flipping speed of the cover plate fast, then slow down, and finally fall slowly at a constant speed, thus completing the slow and silent fall of the cover plate at a constant speed.

[0063] Refer to Figure 2 , Figure 3 Figure 5 and Figure 8 , the piston 3 is divided into two major parts in the overall structure. One part is the cylindrical plug body 31, and different matching structures are provided on both the inner ring surface and the outer ring surface of the cylindrical plug body 31. The other part is the convex edge 32, and the convex edge 32 is used to limit the plug ring 4. The specific positional relationship is as follows: The piston 3 includes a cylindrical plug body 31 that axially moves inward in the shaft cavity 10, and a convex edge 32 that extends from the cylindrical plug body 31 towards the end of the outer shaft section of the rotating shaft 2. The plug ring 4 reciprocates between the outer ring surface of the cylindrical plug body 31 close to the outer shaft section of the rotating shaft 2 and the convex edge 32. A neck is formed between the convex edge 32 and the outer ring surface of the cylindrical plug body 31, and the plug ring 4 moves within the neck. When the plug ring 4 moves to the cylindrical plug body 31, it will block the outer oil passage 3a, and when the plug ring 4 moves to the convex edge 32, the damping oil will flow through the outer oil passage 3a towards the gland 5 side.

[0064] As mentioned above, only axial movement occurs between the piston 3 and the shaft cavity 10 of the shaft sleeve 1. The reason why it cannot rotate radially is that the cylindrical plug body 31 includes a number of guiding grooves 311 provided radially. A number of guiding ribs 101 corresponding to the guiding grooves 311 are fixedly connected to the inner wall of the shaft cavity 10. One end of the guiding groove 311 close to the inner circular hole 302 is open, and the end far from the inner circular hole 302 is closed. Among them, the maximum moving stroke of the cylindrical plug body 31 is the length of the guiding rib 101, that is, after the cylindrical plug body 31 moves the longest distance, the guiding groove 311 will not disengage from the guiding rib 101, which is convenient for its reset. And in order to prevent the damping oil from flowing out of the guiding groove 311, one end of the guiding groove 311 can only be in a closed state, and only the side cooperating with the guiding rib 101 is open.

[0065] Referring to Figure 5 as shown, the cylindrical plug body 31 further includes a plurality of outer oil passages 3a opened in the radial direction, the outer oil passages 3a are arranged at intervals and staggered with the guide grooves 311, and both ends of the outer oil passages 3a are open. As Figures 10-12 shown, when the plug ring 4 presses against the outer oil port 3a1 of the outer oil passage 3a, the outer oil passage 3a is closed and the damping oil flows into the outer screw shaft section 21; as Figure 13 shown, when the plug ring 4 moves away from the outer oil port 3a1 of the outer oil passage 3a, the outer oil passage 3a is opened and the damping oil moves along the outer oil passage 3a in the direction close to the gland 5. In order to facilitate the rapid circulation of the damping oil, there is more than one outer oil passage 3a. The outer oil passage 3a and the inner wall of the shaft cavity 10 form a sealed flow passage. One end of the outer oil passage 3a with an opening away from the gland 5 communicates with the damping oil accommodating cavity formed by the inner round hole 302 and the shaft cavity 10, and the other end close to the gland 5 communicates with the one-way valve Q, so that the damping oil can flow from the damping oil accommodating cavity to the one-way valve Q, so that there will be no oil pressure difference due to the enclosure at both ends of the piston 3 in the shaft cavity 10 of the shaft sleeve 1, that is, the damping oil has no hydraulic damping effect on the piston 3, so that the rotating shaft 2 can drive the piston 3 to rotate quickly.

[0066] Referring to Figure 4 、 Figures 10-12 as shown, when the plug ring 4 presses on the outer oil port 3a1, the damping oil cannot flow back into the outer oil passage 3a. Therefore, the area where the damping oil is located at this time is the high-pressure area. Although a large amount of damping oil cannot flow in due to the sealing of the outer oil port 3a1, the damping oil can still flow in through the gap between the plug ring 4 and the shaft cavity 10, and the pressure in the high-pressure area is still rising continuously. Since a strain gap 40 is opened in the radial direction of the plug ring 4, the damping oil in the high-pressure area will be pressed into the strain gap 40, making the strain gap 40 larger, forming a pressure on the plug ring 4, causing the plug ring 4 to be pressed so that the strain gap 40 expands to make the plug ring 4 press against the inner wall of the shaft cavity 10, so as to completely isolate the low-pressure area from the high-pressure area. The damping oil can only flow back and relieve pressure through the inner oil passage 3b. At the same time, the strain gap 40 can also facilitate the entire plug ring 4 to be embedded in the neck of the piston 3, which is convenient for installation.

[0067] Referring to Figure 4 and Figure 13As shown, the plug ring 4 must ensure that it can close the outer oil passage 3a when it fits with the cylindrical plug body 31. At the same time, it does not affect the flow of damping oil to the high-pressure area when it fits with the convex edge 32. The plug ring 4 includes a circular ring 41 sleeved between the cylindrical plug body 31 and the convex edge 32. The circular ring 41 includes a number of limiting convex parts 411 arranged equidistantly and uniformly on its inner ring surface, and oil passage concave parts 412 opened in the gaps between the limiting convex parts 411. The positions of the limiting convex parts 411 correspond to the positions of the outer oil passage openings 3a1. The limiting convex parts 411 abut against the outer oil passage openings 3a1 or the convex edge 32 as the plug ring 4 moves. When the limiting convex parts 411 are in contact with the cylindrical plug body 31, they can close the outer oil passage 3a. When they fit with the convex edge 32, due to their certain thickness, there is still a certain gap after abutting against the convex edge 32. Therefore, the damping oil can flow through the oil passage concave parts 412 in the direction of the gland 5, and will not accumulate at the neck of the plug ring 4.

[0068] Refer to Figure 4 、 Figures 10-12 As shown, after the pressure in the high-pressure area rises, it will expand the circular ring 41 outward. If it is a simple circular ring structure, a relatively large pressure is required for outward expansion, which is likely to damage the structure of the entire bushing 1. Therefore, a uniform expansion ring cone surface 42 is connected to the side of the circular ring 41 close to the gland 5. After the strain gap 40 is affected by the damping oil pressure, it will expand the diameter of the expansion ring cone surface 42 and abut against the inner wall of the shaft cavity 10. Through the expansion ring cone surface 42 with an outward expansion amplitude, when the oil pressure rises, it will squeeze the expansion ring cone surface 42 and push it outward, thereby reducing the outward expansion pressure, so that the pressure rise is within the tolerable range of the bushing 1 to form a high-pressure area.

[0069] Refer to Figure 4 and Figure 13 , after all the damping oil has flowed back through the inner oil passage 3b, at this time the cover plate is in a horizontal state. When the user needs to use the toilet, normally the cover plate will be quickly lifted. In order to make the resistance felt by the user when lifting the cover plate less, a uniform contraction ring cone surface 43 is connected to the side of the circular ring 41 away from the gland 5. The damping oil entering from the outer oil passage opening 3a1 will compress the contraction ring cone surface 43 inward, so that the strain gap 40 is compressed in diameter and separated from the inner wall of the shaft cavity 10 to allow the damping oil to pass quickly. That is, the damping oil flowing in from the outer oil passage opening 3a1 can make the diameter of the strain gap 40 smaller more quickly when it touches the contraction ring cone surface 43 with a certain arc, and make the time for the circular ring 41 to contract in diameter shorter, so that the user will not feel any jamming or resistance during the process of quickly lifting the cover plate.

[0070] Refer to Figures 10-12, during the process of the damping oil flowing back through the inner oil passage 3b, the rotating shaft 2 is also constantly rotating, and the outer screw shaft section 21 and the gradient circular shaft section 22 are also constantly rotating. The gradient circular shaft section 22 and the inner circular hole 302 form an opening valve Z. The gradient circular shaft section 22 includes a closed diameter 221, a gradually changing diameter 222, and an opening diameter 223 that are sequentially connected in the extending direction of the outer screw shaft section 21. When the piston 3 moves in the direction close to the gland 5, the opening diameter 223, the gradually changing diameter 222, and the closed diameter 221 are sequentially matched with the inner circular hole 302. The rotation of the outer screw shaft section 21 drives the piston 3 to move in the direction of the gland 5, and the inner circular hole 302 in the piston 3 continuously changes its position. Among them, during the process of the inner circular hole 302 changing its position, it will be sequentially matched with the opening diameter 223, the gradually changing diameter 222, and the closed diameter 221, so that the rotation speed of the rotating shaft 2 changes from fast to slow and from slow to uniform speed, enabling the cover plate to quickly fall, and then to slowly descend at a uniform speed after falling to a certain angle.

[0071] In the above embodiment, the various parts of the gradient circular shaft section 22 have unequal diameters. However, equal diameters do not affect the use of the gradient circular shaft section 22. In another embodiment of this case, refer to Figure 14 , the gradient circular shaft section 22 is a mating shaft connected to the outer screw shaft section 21. The head and tail of the mating shaft have equal diameters. The mating shaft includes a large diameter portion 227 connected to the outer screw shaft section 21, a gradually changing groove 228 provided on the side of the large diameter portion 227 away from the gland 5 and with a gradually increasing groove width, and a small diameter groove 229 communicating with the gradually changing groove 228 and having a groove width less than or equal to the end diameter length of the gradually changing groove 228. It can be clearly seen from the figure that the gradient circular shaft section 22 has equal diameters from beginning to end at this time. However, two grooves are provided on the gradient circular shaft section 22, namely the gradually changing groove 228 and the small diameter groove 227, and the achieved effect is the same as that of the gradually changing diameter 222 and the opening diameter 223 in the above embodiment, while the technical effect of the large diameter portion 229 is the same as that of the closed diameter 221. Through the small diameter groove 227, oil quickly passes through in the early stage, causing the cover plate to quickly descend. At the gradually changing diameter 222, the oil passing area decreases, and the cover plate begins to decelerate. Until reaching the position of the large diameter portion 227, the groove completely disappears, the oil passing area is stable, and the oil passing speed is slow and stable. The cover plate begins to descend at a uniform speed, achieving the same technical effect as the above embodiment.

[0072] The above is only the preferred embodiment of the present invention and is not used to limit the present invention. For those skilled in the art, various modifications and changes can be made to the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A rotary damping mechanism, comprising: A shaft sleeve (1) filled with damping oil in a shaft cavity (10), a rotating shaft (2) with an inner shaft section (20) in sealed rotational fit with the shaft cavity (10), and a gland (5) for sealing the opening of the shaft sleeve (1), characterized in that it further comprises: A piston (3) rotatably mounted in the shaft cavity (10) and cooperating with the rotating shaft (2). The piston (3) includes a central hole (30) axially formed, and the central hole (30) is composed of a threaded hole (301) and an inner circular hole (302). The inner shaft section (20) includes an external threaded shaft section (21) and a gradient circular shaft section (22). The external threaded shaft section (21) is screwed into the threaded hole (301) so that the rotating shaft (2) can actuate the piston (3) to reciprocate axially in the shaft cavity (10) to flex and press the damping oil. The gap between the piston (3) and the wall of the shaft cavity (10) forms an external oil passage (3a) of the piston (3), and the clearance between the threaded hole (301) and the external threaded shaft section (21) forms an internal oil passage (3b) of the piston (3). A plug ring (4) that can move axially is installed on the end of the piston (3) close to the outer shaft section of the rotating shaft (2). A strain gap (40) is formed in the radial direction of the plug ring (4), and the strain gap (40) provides a strain space for the radial expansion or contraction of the plug ring (4). The plug ring (4), the piston (3), and the wall of the shaft cavity (10) cooperate to form a one-way valve (Q) for opening and closing the external oil passage (3a), and the inner circular hole (302) and the gradient circular shaft section (22) cooperate to form an opening degree valve (Z) for opening and closing the internal oil passage (3b). When the rotating shaft (2) actuates the piston (3) to move until both the one-way valve (Q) and the opening degree valve (Z) are closed, the damping oil slowly seeps through the external oil passage (3a) and / or the internal oil passage (3b). The oil pressure difference at both ends of the piston (3) in the shaft cavity (10) slowly decays, and the decayed oil pressure brakes the slow movement of the piston (3) to make the rotating shaft (2) rotate slowly.

2. The rotary damping mechanism according to claim 1, characterized in that, The piston (3) includes a cylindrical plug body (31) axially movable in the shaft cavity (10), and a convex edge (32) extending from the cylindrical plug body (31) toward the end close to the outer shaft section of the rotating shaft (2). The plug ring (4) reciprocates between the outer ring surface of the cylindrical plug body (31) close to the outer shaft section of the rotating shaft (2) and the convex edge (32).

3. The rotary damping mechanism according to claim 2, characterized in that, The cylindrical plug body (31) includes a plurality of guiding grooves (311) formed in the radial direction. A plurality of guiding ribs (101) corresponding to the guiding grooves (311) are fixedly connected to the inner wall of the shaft cavity (10). One end of the guiding groove (311) close to the inner circular hole (302) is open, and the end far from the inner circular hole (302) is closed.

4. The rotary damping mechanism according to claim 3, characterized in that, The cylindrical plug body (31) further includes a plurality of outer oil passages (3a) opened in the radial direction. The outer oil passages (3a) are arranged at intervals and staggered with the guide grooves (311). Both ends of the outer oil passages (3a) are open. When the plug ring (4) presses against the outer oil outlet (3a1) of the outer oil passage (3a), the outer oil passage (3a) is closed and the damping oil flows into the external screw shaft section (21). When the plug ring (4) moves away from the outer oil outlet (3a1) of the outer oil passage (3a), the outer oil passage (3a) is opened and the damping oil moves along the outer oil passage (3a) towards the side close to the gland (5).

5. The rotary damping mechanism according to claim 4, characterized in that, The plug ring (4) includes a circular ring (41) sleeved between the cylindrical plug body (31) and the convex edge (32). The circular ring (41) includes a plurality of limiting convex parts (411) arranged at equal distances and evenly distributed on its inner ring surface, and oil passing concave parts (412) opened in the gaps between the limiting convex parts (411). The positions of the limiting convex parts (411) correspond to those of the outer oil outlets (3a1). The limiting convex parts (411) abut against the outer oil outlets (3a1) or the convex edge (32) as the plug ring (4) moves.

6. The rotary damping mechanism according to claim 5, characterized in that, One side of the circular ring (41) close to the gland (5) is connected with a uniform expansion ring cone surface (42). After being subjected to the damping oil pressure, the strain gap (40) expands the diameter of the uniform expansion ring cone surface (42) and then abuts against the inner wall of the shaft cavity (10).

7. The rotary damping mechanism according to claim 5, characterized in that, One side of the circular ring (41) away from the gland (5) is connected with a uniform contraction ring cone surface (43). The damping oil entering from the outer oil outlet (3a1) will compress the uniform contraction ring cone surface (43) inwards, so that the strain gap (40) is compressed in diameter and separated from the inner wall of the shaft cavity (10) to allow the damping oil to pass through quickly.

8. The rotary damping mechanism according to claim 1, characterized in that, The gradient circular shaft section (22) includes a closed diameter (221), a gradually changing diameter (222), and an opening diameter (223) connected in sequence along the extending direction of the external screw shaft section (21). When the piston (3) moves in the direction close to the gland (5), the opening diameter (223), the gradually changing diameter (222), and the closed diameter (221) are sequentially matched with the inner circular hole (302).

9. The rotary damping mechanism according to claim 1, characterized in that, The gradient circular shaft section (22) is a mating shaft connected to the external screw shaft section (21). The head and tail of the mating shaft have the same diameter. The mating shaft includes a large diameter part (227) connected to the external screw shaft section (21), a gradually changing groove (228) arranged on the side of the large diameter part (227) away from the gland (5) and with the groove width gradually increasing, and a small diameter groove (229) communicated with the gradually changing groove (228) and with the groove width less than or equal to the diameter length of the end section of the gradually changing groove (228).

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