CN219720823U - Obstetric membrane rupture device for obstetrics and gynecology department - Google Patents

Abstract

The utility model provides a obstetric membrane rupture device for obstetrics and gynecology. The tire membrane collecting device at least comprises a membrane breaking blade, a tire membrane collecting assembly, an air pump, a bearing, an outer cylinder, a catheter and an inner cylinder, wherein the inner cylinder is connected with the outer cylinder through at least one bearing arranged in the outer cylinder, and the tire membrane collecting assembly is arranged at a first end face of the inner cylinder; under the condition that the air pump works, negative pressure is generated inside the outer cylinder, the tire is contacted with the tire membrane capturing component based on the negative pressure generated inside the outer cylinder, the tire membrane capturing component is rotated to capture the tire membrane, and the tire membrane is contacted with the membrane breaking blade to break in the rotating process.

Description

Obstetric membrane rupture device for obstetrics and gynecology department

Technical Field

The utility model relates to the field of medical equipment, in particular to a obstetric and midwifery membrane rupture device for obstetrics and gynecology.

Background

The artificial rupture of membranes, i.e. the artificial intervention of the amniotic membrane at the lacerated uterine opening, is convenient for observing the color of amniotic fluid, enhancing uterine contraction and accelerating the progress of labor, and is a common labor induction mode in the natural delivery process. The artificial rupture of membranes is one of the common medical intervention means for promoting the labor of obstetrics and gynecology, and a membrane breaker is needed in the clinical practice of obstetrics and gynecology.

In clinical rupture of membranes operation of gynaecology and obstetrics, obstetrician adopts rupture of membranes apparatus usually, present rupture of membranes instrument is mainly with the pjncture needle, mostly directly puncture the amniotic membrane that contains the fetus through the syringe needle, make amniotic fluid flow, this kind of apparatus relies on medical staff's experience to operate completely when rupture of membranes, the accuracy of rupture of membranes is lower, technical skill to doctor requires relatively high, and the degree of depth is difficult to master when puncturing the fetal membrane, puncture degree is too dark and can harm the fetus, moreover, the pjncture needle causes the damage to the vagina easily when passing through the vagina, and the bore size of rupture of unable control in the operation process often can lead to the breach too big, amniotic fluid flows out fast in a large number, lead to amniotic fluid unable to be collected, can not in time collect the amniotic fluid that flows out, often lead to the uterine infection, thereby bring life danger for fetus and lying-in time, and the clearance to amniotic fluid is also troublesome.

The patent with the publication number of CN213098220U discloses a membrane breaker for clinical obstetrics, which comprises a tube body, wherein a groove is formed in the tube body, a sliding sleeve is inlaid at the right end of the tube body, a sliding rod is connected in the sliding sleeve in a sliding manner, a threaded column is fixedly connected to the left end of the sliding rod, a threaded cylinder is connected to the left end surface of the threaded column in a threaded manner, a needle is fixedly connected to the left end of the threaded cylinder, the surface of the threaded cylinder is overlapped with the inner wall of the groove, and a cavity is formed in the tube body; according to the utility model, the air bag can be inflated and deflated through the arrangement of the air bag under the cooperation of the rubber saccule and the exhaust valve, so that the damage of the tube body to the inner wall of the vagina of a patient is avoided, and the needle head and the rotary table are arranged under the cooperation of the threaded cylinder and the threaded column, and the rotary table drives the needle head to move leftwards through the sliding rod by rotating the rotary table, so that the fetal membranes in the vagina of the patient are crushed.

The patent with the publication number of CN212755843U discloses a rupture of membranes clamp, it contains rupture of membranes body, branch, the pjncture needle, the fixed block, the fixed cylinder, push away the handle, guide bar and fulcrum shaft, the fixed block is fixed with to the right side bottom front and back symmetry of fixed cylinder, open the fluting in the fixed cylinder, the guide slot has been seted up in the fixed cylinder that is located the fluting downside, be provided with the back shaft through bearing spin between two fixed blocks around, the cover is fixed with the push away the handle on the back shaft, after the upper end of push away the handle passed the guide slot, set up in the fluting, the sliding tray has been seted up to the upper end of push away the handle, both sides all are provided with the guide bar around pushing away the handle, one side of guide bar is fixed with the guide block, be provided with the fulcrum shaft through bearing spin between two guide bars around, the fulcrum shaft wears to establish in the sliding tray, the left end of fixed cylinder is fixed with rupture of membranes body, move through driving the branch shaft, make the pjncture needle move, thereby change the length of stretching into of pjncture needle, make puncture to the fetal membrane carry out the in-process, can not cause the damage.

The patent with the publication number of CN212186652U discloses a disposable manual membrane rupture needle, which solves the problems that the prior injection needle is inconvenient to hold, and the needle point is easy to scratch a fetus or stab medical staff. The membrane rupture device comprises a hollow storage barrel, wherein a membrane rupture needle is slidably arranged in the storage barrel, and the lower end of the membrane rupture needle is positioned in the storage barrel and can slide out of the lower part of the storage barrel; the lower end of the membrane breaking needle is coated with a rubber layer; the lower end of the storage barrel is provided with a control part which is a structure for controlling the movement of the membrane rupture needle.

In order to prevent amniotic fluid and other substances from directly flowing into the air pump, the amniotic fluid and other substances can be prevented by arranging an additional accommodating space between the air pipe and the air pump. For example, chinese patent with publication number CN212879506U discloses a gynaecology and obstetrics amniotic fluid rupture drainage device, including the drainage tube with hold the case, the top fixedly connected with of drainage tube is in the bottom of drainage head, the top fixedly connected with rubber guard circle of drainage head, the middle part inner chamber spiro union of drainage head has the rupture of membranes sword, the middle part of drainage tube is equipped with the fixed block, the upside and the downside at both ends all are equipped with fixed rope about the fixed block, the connector is gone up to drainage tube bottom fixedly connected with, the bottom fixedly connected with sealing washer of going up the connector, the left side fixedly connected with water pipe at case top is held, the top fixedly connected with lower connector of water pipe, the top right side fixedly connected with air pump of holding the case. When the rupture of membranes sword of this technical scheme touches the sheep water film, set for the pressure that holds the case through control panel, the air pump begins the work this moment, will hold incasement air and pass through two-way pneumatic valve discharge, until pressure detector detects and reaches drainage pressure, rethread control panel adjusts the restriction air output, rupture of membranes sword is influenced by pressure this moment, the amniotic fluid is constantly input to hold the case until the amniotic fluid is discharged completely through drainage head, drainage tube, water pipe constantly, rethread control panel control air pump is to holding the case in injection a small amount of air, take out the device can, can not exert an influence to the normal work of air pump in whole operation process.

Most of the prior art adopts the mode of puncture to rupture membranes, and the degree of depth is difficult to master when puncturing the fetal membranes, and the puncture degree is too dark and can harm the fetus, and the pjncture needle causes the damage to the vagina when passing through the vagina in addition to the bore size of rupture can't be controlled in the operation process, consequently, need improve prior art, design a gynaecology and obstetrics's midwifery rupture membrane device and solve above-mentioned problem.

Furthermore, there are differences in one aspect due to understanding to those skilled in the art; on the other hand, as the inventors studied numerous documents and patents while the present utility model was made, the text is not limited to details and contents of all that are listed, but it is by no means the present utility model does not have these prior art features, the present utility model has all the prior art features, and the applicant remains in the background art to which the rights of the related prior art are added.

Disclosure of Invention

Aiming at the defects of the prior art, the utility model provides a obstetric midwifery membrane rupture device for obstetrics and gynecology, which at least comprises a membrane rupture blade, a membrane capture assembly, an air pump, a bearing, an outer cylinder, a conduit and an inner cylinder, wherein the inner cylinder is connected with the outer cylinder through at least one bearing arranged in the outer cylinder, the membrane capture assembly is arranged at the first end face of the inner cylinder, under the condition that the air pump works, negative pressure is generated in the inner cylinder, the membrane is contacted with the membrane capture assembly based on the negative pressure generated in the outer cylinder, the membrane capture assembly is rotated to capture the membrane, and the membrane is contacted and ruptured with the membrane rupture blade in the rotation process.

According to a preferred embodiment, the fetal membrane capturing assembly comprises a protrusion, an air passage and a base, wherein the base is arranged on the first end face of the inner cylinder, and a part of the base, which is not contacted with the first end face of the inner cylinder, is arranged in a smooth curved surface manner; the bulges are arranged on the curved surface of the base in a mode of interval; the air passage is arranged in a mode of conducting the inner cavity of the outer cylinder and the inner cavity of the inner cylinder.

According to a preferred embodiment, the number of the rupture blades is plural, and the plurality of rupture blades are circumferentially arranged on the inner wall of the outer cylinder in a manner of being spaced and close to the fetal membrane capturing assembly.

According to a preferred embodiment, the outer wall of the outer cylinder is provided with a film suction opening, wherein the side wall of the film suction opening has an arc, and the film suction opening is close to the upper end of the outer cylinder and wraps the port of the outer cylinder.

According to a preferred embodiment, the protrusion is provided with an arc-shaped cutting edge, the protrusion is circumferentially arranged on the curved surface of the base, and the air passage is arranged in a manner of being connected with the arc-shaped cutting edge provided with the protrusion.

According to a preferred embodiment, the inner cylinder is rotatably connected to the outer cylinder on the basis of the bearing, wherein the bearing is arranged in such a way that the outer bearing wall is connected to the outer cylinder and the inner bearing wall is connected to the inner cylinder, and wherein the inner cylinder is arranged in such a way that more membranes can be turned into the device on the basis of the bearing in case of a membrane being in contact with the membrane capturing assembly.

According to a preferred embodiment, the inner cylinder is arranged in a manner of being partly wrapped with the inner cylinder, and the surface of the inner cylinder located outside the outer cylinder is provided with a score for increasing friction force when the inner cylinder is rotated.

According to a preferred embodiment, the outer cylinder forms a space for receiving a membrane in such a way that a step is provided at an end of the inner wall near the membrane-breaking blade.

According to a preferred embodiment, the inner cylinder communicates the conduit with the air passage in such a way that an air chamber is provided, wherein a first end of the conduit is connected to the air chamber and a second end of the conduit is connected to the air pump, the conduit being provided in the inner cylinder in a wrapped manner.

According to a preferred embodiment, the air pump is connected to the second end of the inner cylinder, the air pump being arranged in such a way that it can follow the rotation of the inner cylinder and remain in normal operation when the inner cylinder is rotated.

The obstetric and midwifery membrane rupture device provided by the utility model has at least one or more of the following advantages:

(1) According to the utility model, by sucking the fetal membrane into the device and then using the membrane rupture blade to rupture the membrane, the difficult problems that the depth is difficult to grasp and the fetus is possibly damaged due to the too deep penetration depth when the fetal membrane is punctured can be avoided;

(2) Under the condition of using a membrane rupture device to rupture membranes, the utility model avoids damage to organs caused by hard contact between the device and the organs such as vagina, uterus and the like of a pregnant woman by arranging a membrane suction port;

(3) Under the condition that negative pressure is needed, compared with a mode of manually exhausting by adopting a piston, the negative pressure is formed by adopting the mode of exhausting by adopting the air pump, so that the operation needed to be carried out when medical staff breaks the mould is simplified, and the labor intensity of the medical staff is reduced.

Drawings

FIG. 1 is a schematic view of a membrane rupturing device in accordance with a preferred embodiment of the present utility model;

FIG. 2 is a schematic view of a preferred membrane capture assembly of the present utility model;

FIG. 3 is a schematic view of a preferred plenum of the present utility model.

List of reference numerals

100: rupture of membranes device 110: rupture blade 120: fetal membrane capturing assembly

121: protrusion 122: airway 123: base seat

130: film suction port 140: air pump 150: bearing

151: first bearing 152: second bearing 160: outer cylinder

170 conduit 180 inner cylinder

Detailed Description

The following detailed description refers to the accompanying drawings.

In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model.

As shown in fig. 1, the present utility model provides a obstetric and midwifery membrane rupturing device 100 for obstetrics and gynecology. The rupture device 100 includes at least a rupture blade 110, a membrane capture assembly 120, a membrane suction port 130, an air pump 140, a bearing 150, an outer barrel 160, a catheter 170, and an inner barrel 180. The film suction port 130 is located at a first end of the outer tub 160, and the film suction port 130 is provided on an outer wall of the outer tub 160. The inner cylinder 180 is connected to the outer cylinder 160 by at least one bearing 150 disposed inside the outer cylinder 160. Preferably, two bearings 150 are provided within the outer barrel 160. The inner wall of the first end of the outer barrel 160 has a diameter greater than the outer diameter of the bearing 50. The inner wall of the first end of the outer barrel 160 forms an interior cavity for receiving the fetal membrane. The inner wall of the first end of the outer barrel 160 is provided with a rupture blade 110. The rupture blade 110 is provided on the inner wall adjacent to the first port of the outer cylinder 160 in a spaced manner. The first end face of the inner barrel 180 is provided with a membrane capture assembly 120. The inner barrel 180 is provided with an inner cavity forming an air chamber near the portion of the first end that contacts the membrane capture assembly 120. The fetal membrane capturing assembly 120 is configured with an airway 122. The air passage 122 communicates the inner chamber of the outer barrel 160 with the air chamber of the inner barrel 180. The conduit 170 is disposed inside the inner barrel 180. The first end of the conduit 170 is connected to the plenum of the inner barrel 180. A second end of the conduit 170 is connected to the air pump 140. The air pump 140 is disposed on the second end surface of the inner cylinder 180. Under the condition that the air pump 140 is operated, the air in the inner cavity of the outer cylinder 160 is pumped away by the air pump 140 through the air flow channel, so that a negative pressure environment is generated. The airflow path is formed by the air channel 122, the air chamber and the duct 170. The membrane is contacted with the membrane capturing component 120 based on the negative pressure generated by the inner cavity of the outer barrel 180, the membrane capturing component 120 is rotated to capture the membrane, and the membrane is contacted and ruptured with the rupture blade 110 in the rotating process.

Preferably, the number of rupture blades 110 is plural, and the plurality of rupture blades 110 are circumferentially arranged on the inner wall of the outer cylinder 160 in a spaced manner and close to the fetal membrane capturing assembly 120. Preferably, the plurality of rupture blades 110 are evenly distributed on the inner wall of the outer barrel 160 adjacent the fetal membrane capturing assembly 120. Preferably, the edge of the rupture blade 110 is not directed towards the fetus, so that it is possible to avoid scratching the fetus during rupture.

Preferably, the outer cylinder 160 forms a space for accommodating the membrane in such a manner that a step is provided at an end of the inner wall near the membrane rupturing blade 110.

Preferably, the outer wall of the outer cylinder 180 is provided with a film suction port 130. The side wall of the film suction opening 130 has an arc. The suction port 130 is near the upper end of the outer tub 180 and wraps the port of the outer tub 180. Preferably, the suction port 130 is made of an elastic material. Preferably, the suction port 130 may be made of silica gel. In the case of rupture using the present utility model, the membrane suction port 130 can be closely attached to the fetal membrane to form an airtight space.

Preferably, the inner barrel 180 is disposed in a partially wrapped relationship with the inner barrel 160. The surface of the inner cylinder 180 outside the outer cylinder 160 is provided with notches for increasing friction force when the inner cylinder 180 is rotated.

Preferably, the inner barrel 180 is rotatably coupled to the outer barrel 180 based on bearings 150. The bearing 150 is provided such that the outer wall of the bearing 150 is connected to the outer tube 160 and the inner wall of the bearing 150 is connected to the inner tube 180. With the membranes in contact with the membrane capture assembly 120, the inner barrel 180 is arranged in such a way that it can rotate based on the bearings 150 to allow more membrane access means. Preferably, the bearing 150 is provided with two, a first bearing 151 and a second bearing 152, respectively. The first bearing 151 is disposed proximate the tire membrane capturing assembly 120 and the second bearing 152 is disposed at the interface of the outer barrel 160 and the inner barrel 180.

Preferably, the air pump 140 is connected to a second end of the inner barrel 180. Preferably, the air pump 140 is connected to the second end of the inner cylinder 180 by bolts. The air pump 140 is provided in such a manner as to be able to follow the rotation of the inner cylinder 180 and maintain normal operation in the case of rotating the inner cylinder 180. Preferably, rotating the inner barrel 180 can drive the air pump 140 and the membrane capture assembly 120.

Referring to fig. 2-3, fetal membrane capture assembly 120 includes protuberance 121, airway 122, and base 123. The base 123 is disposed on the first end surface of the inner cylinder 180, and a portion of the base 123 not contacting the first end surface of the inner cylinder 180 is disposed in a rounded shape. The protrusions 121 are disposed on the curved surface of the base in a spaced manner. The air passage 122 is provided in a manner to communicate the inner cavity of the outer barrel 160 with the inner cavity of the inner barrel 180.

Preferably, the protrusion 121 is configured with an arc-shaped cutting edge. The protrusions 121 are circumferentially arranged on the curved surface of the base 123. Airway 122 is configured to connect with the arcuate edge of protuberance 121.

Preferably, the inner tube 180 communicates the conduit 170 with the air passage 122 in a manner that provides an air chamber, wherein a first end of the conduit 170 is connected to the air chamber and a second end of the conduit is connected to the air pump 140, and the conduit 170 is disposed within the inner tube 180 in a wrapped manner.

Preferably, the air pump 140 absorbs the air in the air chamber through the conduit 170, and the air channel 122 conducts the inner cavity of the outer cylinder 160 and the inner cavity of the inner cylinder 180, and the film sucking opening 130 is tightly attached to the tire film to form an airtight space, so that a negative pressure environment is formed in the inner cavity of the outer cylinder 160 and the inner cavity of the inner cylinder 180 in the air sucking process of the air pump 140. The membranes enter the inner cavity of the outer cylinder 160 from the membrane suction port 130 under the action of negative pressure and are contacted with the membrane capturing assembly 120. Preferably, the membranes are preferentially in contact with the protrusions 121 of the membrane capture assembly 120. The membrane is in close contact with the protuberance 121 by the air passage 122. The membranes entering the lumen of the outer barrel 160 are in contact with the protrusions 121 provided on the membrane capturing assembly 120 based on the action of the negative pressure at the air passage 122. With the air pump 140 kept on, the inner cylinder 180 is rotated to thereby rotate the membrane capture assembly 120. Protrusions 121 provided on the membrane catcher assembly 120 hook the contacted membranes. Due to the rotation of the membrane capturing assembly 120, the protrusions 121 provided on the membrane capturing assembly 120 hook more membranes into the inner cavity of the outer barrel 160. After being hooked by the protrusions 121, the membranes enter the inner cavity of the outer cylinder 160 and are contacted and ruptured by the membrane rupturing blades 110 which are arranged on the inner wall of the outer cylinder 160 and are close to the membrane capturing assembly 120.

For the convenience of understanding, the working principle of the obstetric and gynecologic midwifery membrane rupture device is described.

According to the obstetric and midwifery membrane rupture device, under the condition that artificial membrane rupture is needed, medical staff enables a membrane suction port of the device to contact with a fetal membrane, and an air pump is started. The air pump absorbs the air in the air chamber through the guide pipe, and the air channel conducts the inner cavity of the outer cylinder and the inner cavity of the inner cylinder, so that a negative pressure environment is formed in the inner cavity of the outer cylinder and the inner cavity of the inner cylinder in the air pumping process of the air pump. The fetal membranes enter the inner cavity of the outer cylinder of the device under the action of negative pressure and are contacted with the fetal membrane capturing component. Medical staff rotates the fetal membrane capturing assembly arranged on the inner cylinder in a mode of rotating the inner cylinder. The base of the fetal membrane capturing component is provided with a bulge with an arc-shaped cutting edge, and the bulge with the arc-shaped cutting edge can be hooked on the fetal membrane under the condition that the fetal membrane capturing component is contacted with the fetal membrane and the fetal membrane capturing component rotates. With the rotation of the membrane capturing assembly, more and more membranes are hooked by the protrusions into the device until the membranes are broken by contact with the rupture blade. The utility model successfully avoids the problem of bad grasp of the puncture depth caused by using the puncture method. The fetal membrane is treated after being captured by the fetal membrane capturing component, so that the safety of a fetus is ensured. The utility model generates negative pressure through the air pump, and reduces the labor intensity of medical staff compared with the negative pressure generated by using the piston for pumping.

It should be noted that the above-described embodiments are exemplary, and that a person skilled in the art, in light of the present disclosure, may devise various solutions that fall within the scope of the present disclosure and fall within the scope of the present disclosure. It should be understood by those skilled in the art that the present description and drawings are illustrative and not limiting to the claims. The scope of the utility model is defined by the claims and their equivalents.

Claims (6)

1. A obstetric and midwifery membrane rupturing device for obstetrics and gynecology is characterized by at least comprising a membrane rupturing blade (110), a membrane capturing assembly (120), an air pump (140), a bearing (150), an outer cylinder (160), a conduit (170) and an inner cylinder (180), wherein,

the inner cylinder (180) is connected with the outer cylinder (160) through at least one bearing (150) arranged in the outer cylinder (160), the first end surface of the inner cylinder (180) is provided with the fetal membrane capturing component (120),

the fetal membrane capturing assembly (120) comprises a protrusion (121), an air passage (122) and a base (123), wherein,

the base (123) is arranged on the first end surface of the inner cylinder (180), and a part of the base (123) which is not contacted with the first end surface of the inner cylinder (180) is arranged in a smooth curved surface manner;

the protrusions (121) are arranged on the curved surface of the base (123) in a spaced manner;

the air passage (122) is arranged in a mode of conducting the inner cavity of the outer cylinder (160) and the inner cavity of the inner cylinder (180);

the bulge (121) is provided with an arc-shaped cutting edge, the bulge (121) is circumferentially arranged on the curved surface of the base (123), and the air passage (122) is arranged in a mode of being connected with the arc-shaped cutting edge arranged on the bulge (121);

the inner cylinder (180) is used for conducting the conduit (170) and the air passage (122) in a mode of arranging an air chamber, wherein a first end of the conduit (170) is connected to the air chamber, a second end of the conduit (170) is connected to the air pump (140), and the conduit (170) is arranged in the inner cylinder (180) in a wrapped mode;

the air pump (140) is arranged in a mode of pumping air in the inner cavity of the outer cylinder (160) through an air flow channel, wherein the air flow channel is composed of the air channel (122), the air chamber and the guide pipe (170); the inner cylinder (180) is rotatably connected with the outer cylinder based on the bearing (150), wherein,

the bearing (150) is arranged in a way that the outer wall of the bearing (150) is connected with the outer cylinder (160) and the inner wall of the bearing (150) is connected with the inner cylinder (180),

with the membrane in contact with the membrane capture assembly (120), the inner barrel (180) is arranged in such a way that more membrane access means can be rotated based on the bearings (150);

under the condition that the air pump (140) works, negative pressure is generated inside the outer cylinder (160), the fetal membrane is contacted with the fetal membrane capturing component (120) based on the negative pressure generated inside the outer cylinder (160), wherein the fetal membrane is contacted with the bulge (121) arranged on the fetal membrane capturing component (120) based on the action of the negative pressure at the air passage (122), the fetal membrane capturing component (120) is rotated to capture the fetal membrane, and the fetal membrane is contacted and ruptured with the rupture blade (110) in the rotation process.

2. The membrane rupturing device according to claim 1, wherein the number of the membrane rupturing blades (110) is plural, and the plurality of membrane rupturing blades (110) are circumferentially arranged on the inner wall of the outer cylinder (160) in a manner of being spaced apart and close to the membrane capturing assembly (120).

3. A membrane rupturing device according to claim 2, wherein the outer wall of the outer cylinder (160) is provided with a membrane sucking port (130), wherein,

the side wall of the film sucking opening (130) is provided with an arc, and the film sucking opening (130) is close to the upper end of the outer barrel (160) and wraps the port of the outer barrel (160) inside.

4. A membrane rupturing device according to claim 3, wherein the inner cylinder (180) is arranged in a manner of being partially wrapped with the inner cylinder (160), and a surface of the inner cylinder (180) located outside the outer cylinder (160) is provided with a score for increasing friction force when the inner cylinder (180) is rotated.

5. A rupture disc device according to claim 4, wherein said outer cylinder (160) defines a membrane-receiving space in such a manner that a step is provided at an end of the inner wall adjacent to said rupture blade (110).

6. A membrane rupturing device according to claim 5, wherein the air pump (140) is connected to the second end of the inner cylinder (180), the air pump (140) being arranged in such a way that it follows the rotation of the inner cylinder (180) and remains in normal operation when the inner cylinder (180) is rotated.