Moxibustion equipment for treating polycystic ovarian syndrome
By designing targeted moxibustion devices, the problems of improper waste disposal and insufficient comfort in the treatment of polycystic ovary syndrome have been solved, achieving effective waste collection and comfort adjustment, thus improving the user experience and health safety.
Patent Information
- Application Number
- CN202511987912.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-26
- Publication Date
- 2026-01-27
AI Technical Summary
Existing moxibustion equipment lacks targeted treatment for polycystic ovary syndrome. Improper disposal of waste generated during moxibustion affects health and results in insufficient comfort, leading to a poor user experience.
A moxibustion device for the treatment of polycystic ovary syndrome was designed, comprising a box, a gas filter, a combustion component, an ash collection tray, a metal filter, and a retractable fixing component. Waste is collected through an inclined groove and an S-shaped metal filter. Comfort is adjusted using an airbag, a jet generator is set to improve combustion efficiency, a resistance wire is used to retain heat, and a filter treats smoke.
Effective collection and disposal of moxibustion waste improves comfort, reduces health risks, enhances the user experience, and ensures that the effects of moxibustion are not affected.
Smart Images

Figure CN121401121A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of moxibustion therapy, and more particularly to a moxibustion device for the treatment of polycystic ovary syndrome. Background Technology
[0002] Polycystic ovary syndrome (PCOS) is a chronic disease that requires long-term management. Moxibustion can be used as an adjunct therapy. The gentle and lasting heat stimulation of moxibustion can work synergistically on multiple levels, such as regulating the endocrine axis and improving insulin resistance, providing a safe and convenient home-based supplement to standardized treatment. However, existing moxibustion equipment lacks specificity for the treatment of PCOS, and the waste generated during home use cannot be properly disposed of.
[0003] The moxibustion process generates a large amount of smoke, which contains inhalable particulate matter and gases such as carbon dioxide and carbon monoxide. If these are not properly treated, they can be harmful to human health. During the use of a moxibustion box, the frequent opening and closing of the box can cause contamination inside and is inconvenient for the user. Moxibustion is a long-term process, and since the moxibustion box is in contact with the skin, a lack of comfort adjustments can reduce the user's experience. Summary of the Invention
[0004] To overcome the shortcomings of moxibustion boxes, such as lack of specificity for treating polycystic ovary syndrome (PCOS) and lack of comfort adjustment leading to a poor user experience, as well as the inability to properly dispose of waste generated during moxibustion, which can negatively impact human health, this invention provides a moxibustion device for the treatment of PCOS.
[0005] Technical Solution: A moxibustion device for treating polycystic ovary syndrome includes a box body, a first air inlet, and a second air inlet; a gas filter is provided at each of the left and right ends of the inner side of the box body; a gas diffuser head is fixedly connected to each gas filter; a gas delivery pipe is fixedly connected to the gas diffusers at both ends; four first air inlets arranged in a rectangular array are opened at the upper part of the box body; four sets of second air inlets are opened at the upper part of the box body, and each set of second air inlets is arranged in a circumferential array around a first air inlet; it also includes a combustion component, an ash collection tray, and a metal filter screen; four sets of combustion components arranged in a rectangular array are fixedly connected to the upper part of the inner side of the box body; a retainer is provided on the upper part of each set of combustion components; two ash collection trays are slidably connected to the lower part of the box body, and the two ash collection trays are arranged symmetrically on the left and right; a magnet is provided at the left end of each ash collection tray; a metal filter screen is fixedly connected to the inner side of each ash collection tray; a fixing component is fixedly connected to the lower part of the box body, and the fixing component is located below the ash collection tray.
[0006] Further explanation: The combustion assembly includes a combustion chamber, an oil conduit, a smoke conduit, and inclined slots; four combustion chambers arranged in a rectangular array are fixedly connected to the upper part of the inner side of the box; two oil conduits are fixedly connected to the side of each combustion chamber, and the oil conduits are symmetrically arranged left and right; two smoke conduits are fixedly connected to the side of each combustion chamber, and the smoke conduits are symmetrically arranged front and back; several sets of moving components are fixedly connected to the upper part of the inner side of the box, each set of moving components consists of two sliding rods, and each set of moving components is located directly below a first air inlet; a slider is slidably connected to each set of sliding rods; several inclined slots are opened inside the combustion chamber.
[0007] To further explain, the fixing components include fixing blocks, rotating plates, and C-shaped plates; a fixing block is fixed to each of the left and right ends of the lower part of the box, and each fixing block is located below the ash collection tray; each fixing block is hinged to a rotating plate; one end of the C-shaped plate is fixed to the side of each rotating plate; and an elastic strap is fixed to the other end of the C-shaped plate.
[0008] To further explain, the fixing component also includes airbags; an airbag is fixed to each of the left and right ends of the lower part of the box, and the airbags are located on the side of the fixing block.
[0009] To further clarify, the C-shaped plate is made of a stretchable material.
[0010] To further explain, the inclined groove is an annular groove that is higher in the middle and lower on both sides.
[0011] To further explain, the combustion chamber has several oil collection troughs and smoke collection troughs on its inner side, with every two oil collection troughs located at the lowest point of each inclined trough and every two smoke collection troughs located at the highest point of each inclined trough.
[0012] To further explain, the combustion assembly also includes a gas storage chamber, jets, and vents; several gas storage chambers are fixedly connected to the upper part of the inner side of the box, and each gas storage chamber is located directly below each first air inlet and embedded in each set of slide bars; several jets arranged in a circumferential array are fixedly connected to the side of each gas storage chamber, and the jets are set at a certain tilt angle; several vents are opened on the upper part of each gas storage chamber, and each vent communicates with a second air inlet.
[0013] To further explain, the combustion assembly also includes resistance wires; several resistance wires are embedded inside the combustion chamber.
[0014] To further explain, the metal filter screen has a continuous S-shape.
[0015] The beneficial effects of this invention are as follows: This invention designs an annular groove with a high center and low sides. The annular shape can guide the direction of the waste from the burning of moxa sticks. Since the smoke from moxa sticks rises and the particles and oil from moxa sticks fall downwards due to gravity, the high center and low sides design can collect the waste in a targeted manner, reducing the impact of the waste.
[0016] This invention designs a metal filter with a continuous S-shape. The continuous S-shape is designed to prevent the ash from accumulating at the bottom of the moxa stick when it falls, which would prevent the heat generated by the burning moxa stick from being transferred to the human body through the ash and reduce the moxibustion effect. In addition, the S-shape allows the ash to fall to a lower position, reducing the distribution area of the ash and improving the subsequent cleaning efficiency.
[0017] This invention designs the C-shaped plate as a stretchable material. The stretchable material can be used in conjunction with the airbag to adjust the comfort and enhance the user experience. When the invention is not in use, the rotating plates at both ends can be turned into a horizontal state under the action of the torsion springs set in the fixed block. At the same time, the C-shaped plates at both ends are retracted, and the elastic straps at both ends stick together to seal the bottom of the box and prevent dirt from entering the box. Attached Figure Description
[0018] Figure 1 This is a three-dimensional structural diagram illustrating the moxibustion device for treating polycystic ovary syndrome according to the present invention; Figure 2 This is a partial sectional view from a first perspective describing the moxibustion device for treating polycystic ovary syndrome of the present invention; Figure 3 This is a partial sectional view from a second perspective illustrating the moxibustion device for treating polycystic ovary syndrome of the present invention; Figure 4 This is a schematic diagram illustrating the first state of the fixing component of the present invention; Figure 5 This is a schematic diagram illustrating a second state of the fixing component of the present invention; Figure 6 This is a cross-sectional view illustrating a first structural configuration of the combustion assembly of the present invention; Figure 7 This is a schematic diagram illustrating the structure of the moxa stick holder of the present invention; Figure 8 This is a cross-sectional view illustrating a second structural configuration of the combustion assembly of the present invention; Figure 9 A cross-sectional view illustrating the structure of the combustion chamber of this invention; Figure 10 This is a schematic diagram illustrating the structure of the metal filter screen of the present invention.
[0019] In the above attached diagram: 1-box body, 2-gas filter, 3-gas diffuser head, 4-gas delivery pipe, 5-fixer, 6-moxa stick, 10001-first air inlet, 10002-second air inlet; 101-Combustion chamber, 102-Artemisia oil conduit, 103-Artemisia smoke conduit, 104-Slide bar, 105-Slider, 106-Resistance wire, 107-Gas storage chamber, 108-Jet, 10101-Inclined chute, 10102-Oil collection chute, 10103-Smoke collection chute, 10701-Ventilation port; 301 - Ash collection tray, 302 - Magnet, 303 - Metal filter screen; 401-Fixing block, 402-Rotating plate, 403-C-shaped plate, 404-Elastic strap, 405-Airbag. Detailed Implementation
[0020] The invention will now be described more fully below with reference to the accompanying drawings, in which presently preferred embodiments of the invention are illustrated. However, the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided for thoroughness and completeness and to fully convey the scope of the invention to those skilled in the art.
[0021] Example 1: A moxibustion device for the treatment of polycystic ovary syndrome, such as... Figures 1-7 As shown, it includes a housing 1, a first air inlet 10001, a second air inlet 10002, a combustion assembly, an ash collection tray 301, a metal filter screen 303, and a fixing assembly; a gas filter 2 is provided at each of the left and right ends of the inner side of the housing 1; each gas filter 2 is fixedly connected to a gas diffuser head 3; the gas diffusers 3 at the left and right ends are jointly fixedly connected to a gas delivery pipe 4; four first air inlets 10001 arranged in a rectangular array are opened on the upper part of the housing 1; four sets of second air inlets 10002 are opened on the upper part of the housing 1, and each The second air inlet 10002 is arranged in a circumferential array around the first air inlet 10001; four sets of combustion components arranged in a rectangular array are fixed to the upper part of the inner side of the box body 1; a retainer 5 is provided on the upper part of each set of combustion components; two ash collection trays 301 are slidably connected to the lower part of the box body 1, and the two ash collection trays 301 are symmetrically arranged on the left and right sides; a magnet 302 is provided on the left end of each ash collection tray 301; a metal filter screen 303 is fixed to the inner side of each ash collection tray 301; a fixing component is fixed to the lower part of the box body 1, and the fixing component is located below the ash collection tray 301.
[0022] The combustion assembly includes a combustion chamber 101, an oil conduit 102, a smoke conduit 103, a slide bar 104, a slider 105, and an inclined groove 10101. Four combustion chambers 101 arranged in a rectangular array are fixedly connected to the upper inner side of the box body 1. Two oil conduits 102 are fixedly connected to the side of each combustion chamber 101, and the oil conduits 102 are symmetrically arranged from left to right. Two smoke conduits 103 are fixedly connected to the side of each combustion chamber 101, and the smoke conduits 103 are symmetrically arranged from front to back. Several sets of moving components are fixedly connected to the upper inner side of the box body 1. Each set of moving components consists of two slide bars 104, and each set of moving components is located directly below a first air inlet 10001. A slider 105 is slidably connected to each slide bar 104. Several inclined grooves 10101 are opened on the inner side of the combustion chamber 101.
[0023] The fixing components include a fixing block 401, a rotating plate 402, and a C-shaped plate 403; a fixing block 401 is fixedly attached to each of the left and right ends of the lower part of the box body 1, and each fixing block 401 is located below the ash collection tray 301; each fixing block 401 is hinged to a rotating plate 402; one end of the C-shaped plate 403 is fixedly attached to the side of each rotating plate 402. The C-shaped plate 403 is designed to be C-shaped because the treatment sites for polycystic ovary syndrome are mainly in the lumbosacral region and the lower abdomen. These two areas are near the waist of the human body and can be fixed by the waist; an elastic strap 404 is fixedly attached to the other end of the C-shaped plate 403.
[0024] The C-shaped plate 403 is made of a stretchable material. This stretchable material can be used in conjunction with the airbag 405 to adjust the comfort level and enhance the user's experience. When the invention is not needed, the rotating plates 402 at both ends can be turned into a horizontal state under the action of the torsion springs set in the fixing block 401. At the same time, the C-shaped plates 403 at both ends are retracted, allowing the elastic straps 404 at both ends to stick together and seal the bottom of the box 1, preventing dirt from entering the inside of the box 1.
[0025] The fixing component also includes an airbag 405; an airbag 405 is fixed to each of the left and right ends of the lower part of the box body 1, and the airbag 405 is located on the side of the fixing block 401. The airbag 405 is in contact with human skin and can support the entire moxibustion box, playing a supporting role; the internal volume of the airbag 405 is adjustable, and the user can adjust it according to their own needs to achieve the most comfortable state.
[0026] When using moxibustion as an adjunct therapy for patients with polycystic ovary syndrome, the main treatment areas are the lower abdomen and lumbosacral region. Therefore, the patient can untie the elastic straps 404 at both ends and stretch the C-shaped plates 403 at both ends so that the entire device can be fitted around the patient's waist. Then, inflate the airbag 405 so that the airbag 405 comes into contact with the skin. At the same time, adjust the C-shaped plates 403 so that the entire fixation component can fit the patient and make the patient feel comfortable. After completing the wearing, the patient takes out all the fixation devices 5, inserts the moxa stick 6 into the bottom tip of the fixation device 5, and lights the moxa stick 6. The lit moxa stick 6 and the fixation device 5 are inserted from the first air inlet 10001 at the top of the box 1 and placed in the groove on the upper part of the slider 105.
[0027] Example 2, based on Example 1, such as Figures 8-9 As shown, the inclined groove 10101 is an annular groove that is high in the middle and low on both sides. The annular shape can guide the direction of the burning waste of the moxa stick 6. Since the moxa smoke goes upward and the particles and moxa oil are downward due to gravity, the groove is high in the middle and low on both sides to collect the waste in a targeted manner and reduce the impact of the waste.
[0028] The combustion assembly also includes a gas storage chamber 107, a jet injector 108, and a vent 10701; several gas storage chambers 107 are fixedly connected to the upper inner side of the housing 1, and each gas storage chamber 107 is located directly below each first air inlet 10001 and embedded in each set of slide rods 104; several circumferentially arrayed jet injectors 108 are fixedly connected to the side of each gas storage chamber 107, and the jet injectors 108 are set at a certain tilt angle. The jet injectors 108 can spray gas according to the burning status of the moxa stick 6. When the burning degree is low, it is necessary to increase the gas supply. When the moxibustion temperature is reached, gas can be injected into the moxa stick 6 through the jet nozzle 108 to provide sufficient oxygen for the burning of the moxa stick 6, making the burning of the moxa stick 6 more complete. The injected gas can also form a wall to prevent the moxa smoke from flying out of the first air inlet 10001 and to let the moxa smoke fly to the smoke collection groove 10103. The angle of the groove is set to facilitate the entry of air and avoid disturbing the heat field and heat loss. Each air storage chamber 107 has several air vents 10701 on its upper part, and each air vent 10701 is connected to a second air inlet 10002.
[0029] The combustion assembly also includes a resistance wire 106; several resistance wires 106 are embedded in the combustion chamber 101, and the resistance wires 106 can provide a certain amount of heat to the combustion chamber 101; during the moxibustion process, the heat provided by the resistance wires 106 can keep the combustion chamber 101 at a temperature that is conducive to the combustion of the moxa stick 6, which helps the moxa stick 6 to burn completely and reduces the generation of harmful gases and particulate matter; the moxibustion combustion process will produce moxa oil, which will condense inside the combustion chamber 101 when it cools down. Therefore, after the moxibustion is completed, heat can be provided by the resistance wires 106 to raise the internal temperature of the combustion chamber 101 and pyrolyze the moxa oil. The pyrolyzed moxa oil is discharged along the inclined groove 10101 and the oil collection groove 10102 inside the combustion chamber 101.
[0030] The combustion chamber 101 has several oil collection grooves 10102 and smoke collection grooves 10103 on its inner side. Every two oil collection grooves 10102 are located at the lowest point of each inclined groove 10101, and every two smoke collection grooves 10103 are located at the highest point of each inclined groove 10101. The oil collection grooves 10102 and smoke collection grooves 10103 can collect the waste from the burning of the moxa sticks 6 and remove the waste without opening the moxibustion box, thus avoiding the need to open the moxibustion box frequently and providing a certain degree of convenience.
[0031] After the moxa stick 6 is inserted into the combustion assembly, because it is in the initial combustion stage and its temperature is not high, the patient cannot feel the moxibustion effect. At this time, the patient can control each slider 105 to slide up and down each set of sliders 104, bringing the moxa stick 6 closer to the patient's moxibustion site and reducing heat loss. The patient can also turn on the jet system, drawing air from the outside into the air storage chamber 107 through the second air inlet 10002, and then spraying it into the combustion chamber 101 through the jet 108, providing sufficient oxygen for the combustion of the moxa stick 6. This allows the moxa stick 6 to burn more completely and release more heat. The jet 108 is also set at a certain angle to facilitate air entry and avoid disturbing the thermal field and heat loss. The resistance wire 106 embedded inside the combustion chamber 101 is in a normally open state during use, continuously providing heat to the combustion chamber 101, allowing the combustion chamber 101 to quickly reach an ambient temperature suitable for the burning of the moxa stick 6, and preventing the heat released by the burning moxa stick 6 from being consumed by the combustion chamber 101. The stability of the combustion environment helps the moxa stick 6 to burn completely and reduces the generation of harmful gases and particulate matter.
[0032] Example 3, based on Examples 1 and 2, such as Figure 10 As shown, the metal filter 303 is in the shape of a continuous S-shape. The continuous S-shape is designed to prevent the ash from accumulating at the bottom of the moxa stick 6 when it falls, which would prevent the heat generated by the burning moxa stick 6 from being transferred to the human body through the ash and reduce the moxibustion effect. In addition, the S-shape allows the ash to fall to a lower position, reducing the distribution area of the ash and improving the subsequent cleaning efficiency.
[0033] During the combustion of moxa stick 6, a large amount of waste is generated, mainly including inhalable particulate matter and gases such as carbon dioxide and carbon monoxide. These wastes not only remain inside the equipment causing pollution but also harm human health. Therefore, the smoke generated by the combustion of moxa stick 6 is guided into the smoke collection trough 10103 by the inclined chute 10101. The smoke collected at multiple heights enters the moxa smoke conduit 103 and is then uniformly introduced into the gas delivery pipe 4 and introduced into the gas filters 2 at both ends. The gas diffusers 3 at both ends of the gas delivery pipe 4 can increase the contact area between the gas and the gas filters 2, enhancing the filtration effect. The oily substance generated during the combustion of moxa stick 6 adheres to the inner wall of the combustion chamber 101 when it cools. After the moxibustion is completed, the temperature of the resistance wire 106 is increased to allow the temperature inside the combustion chamber 101 to reach the temperature at which the oily substance can be pyrolyzed, turning it into a liquid oily substance that slides down the inner wall of the combustion chamber 101. Guided by the inclined groove 10101, the moxa stick enters the oil collection groove 10102, and then enters the moxa oil conduit 102 through the oil collection groove 10102. An oil container is placed at the bottom of the box body 1 in advance, and the oily substance slides out from the moxa oil conduit 102 into the oil container. The moxa ash produced by the burning moxa stick 6 falls to the metal filter 303. The continuous S-shaped metal filter 303 is set to prevent the moxa ash from accumulating at the bottom of the moxa stick 6 when it falls, so that the heat generated by the burning moxa stick 6 cannot be transferred to the human body through the moxa ash, thus reducing the moxibustion effect. Moreover, the S-shaped setting allows the moxa ash to fall to a lower position, reducing the distribution area of the moxa ash and improving the subsequent cleaning efficiency. After the moxibustion is completed, the patient only needs to wait for the moxa ash to cool down and then pull out the ash collection trays 301 at both ends to pour out the moxa ash. The ash collection trays 301 at both ends are connected by magnets 302 when collecting the moxa ash, ensuring that the ash collection trays 301 are placed accurately and that the lowest point of the metal filter 303 is not directly below the moxa stick 6.
[0034] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A moxibustion device for treating polycystic ovary syndrome, comprising a box body (1); a gas filter (2) is provided at each of the left and right ends of the inner side of the box body (1); a gas diffuser (3) is fixedly connected to each gas filter (2); a gas delivery pipe (4) is fixedly connected to the gas diffusers (3) at both ends; a number of first air inlets (10001) arranged in a rectangular array are provided on the upper part of the box body (1); a number of second air inlets (10002) are provided on the upper part of the box body (1), and each group of second air inlets (10002) is arranged in a circumferential array around a first air inlet (10001); characterized in that, It also includes a combustion assembly, a fixture (5), an ash collection tray (301), a magnet (302), a metal filter (303), and a fixing assembly; a number of sets of combustion assemblies arranged in a rectangular array are fixedly connected to the upper inner side of the box body (1); a fixture (5) is provided on the upper part of each set of combustion assemblies; two ash collection trays (301) are slidably connected to the lower part of the box body (1), and the two ash collection trays (301) are symmetrically arranged on the left and right sides; a magnet (302) is provided on the left end of each ash collection tray (301); a metal filter (303) is fixedly connected to the inner side of each ash collection tray (301); a fixing assembly is fixedly connected to the lower part of the box body (1), and the fixing assembly is located below the ash collection tray (301).
2. The moxibustion device for treating polycystic ovary syndrome according to claim 1, characterized in that: The combustion assembly includes a combustion chamber (101), an oil pipe (102), a smoke pipe (103), a slide bar (104), a slider (105), and an inclined groove (10101); a number of combustion chambers (101) arranged in a rectangular array are fixedly connected to the upper inner side of the box body (1); two oil pipes (102) are fixedly connected to the side of each combustion chamber (101), and the oil pipes (102) are symmetrically arranged on the left and right; two smoke pipes (103) are fixedly connected to the side of each combustion chamber (101), and the smoke pipes (103) are symmetrically arranged front and back; a number of moving components are fixedly connected to the upper inner side of the box body (1), each moving component consists of two slide bars (104), and each moving component is located directly below a first air inlet (10001); a slider (105) is slidably connected to each slide bar (104); a number of inclined grooves (10101) are opened on the inner side of the combustion chamber (101).
3. The moxibustion device for treating polycystic ovary syndrome according to claim 1, characterized in that: The fixing components include a fixing block (401), a rotating plate (402), a C-shaped plate (403), and an elastic strap (404); a fixing block (401) is fixedly connected to each of the left and right ends of the lower part of the box body (1), and each fixing block (401) is located below the ash collection tray (301); each fixing block (401) is hinged to a rotating plate (402); one end of the C-shaped plate (403) is fixedly connected to the side of each rotating plate (402); the other end of the C-shaped plate (403) is fixedly connected to an elastic strap (404).
4. A moxibustion device for treating polycystic ovary syndrome according to claim 3, characterized in that: The fixing component also includes an airbag (405); an airbag (405) is fixed to each of the left and right ends of the lower part of the box body (1), and the airbag (405) is located on the side of the fixing block (401).
5. A moxibustion device for treating polycystic ovary syndrome according to claim 3, characterized in that: C-type panels (403) are made of expandable material.
6. A moxibustion device for treating polycystic ovary syndrome according to claim 3, characterized in that: The inclined groove (10101) is an annular groove that is high in the middle and low on both sides.
7. A moxibustion device for treating polycystic ovary syndrome according to claim 6, characterized in that: The combustion chamber (101) has several oil collection grooves (10102) and smoke collection grooves (10103) on its inner side, with every two oil collection grooves (10102) located at the lowest point of each inclined groove (10101); and every two smoke collection grooves (10103) located at the highest point of each inclined groove (10101).
8. A moxibustion device for treating polycystic ovary syndrome according to claim 7, characterized in that: The combustion assembly also includes a gas storage chamber (107), a jet (108), and a vent (10701); several gas storage chambers (107) are fixedly connected to the upper inner side of the box (1), and each gas storage chamber (107) is located directly below each first air inlet (10001) and embedded in each set of slide rods (104); several jets (108) arranged in a circumferential array are fixedly connected to the side of each gas storage chamber (107), and the jets (108) are set at a certain tilt angle; several vents (10701) are opened on the upper part of each gas storage chamber (107), and each vent (10701) is connected to a second air inlet (10002).
9. A moxibustion device for treating polycystic ovary syndrome according to claim 8, characterized in that: The combustion assembly also includes resistance wires (106); the combustion chamber (101) contains several resistance wires (106).
10. A moxibustion device for treating polycystic ovary syndrome according to claim 9, characterized in that: The metal filter (303) has a continuous S-shape.
