Obstetric delivery device

Abstract

The application belongs to the technical field of medical devices, and particularly discloses a delivery device for obstetrics, which comprises a fetal head sucking disc, a traction pipe arranged at the rear end of the fetal head sucking disc, a force relieving and buffering protection mechanism arranged at the rear end of the traction pipe, and a gas exchange cylinder arranged at the rear of the force relieving and buffering protection mechanism, wherein the outer wall of the gas exchange cylinder is cross-shaped and is connected with a first lifting pipe, a second lifting pipe, a suction hose and a sliding pipe; the end of the first lifting pipe is connected with a first negative pressure cylinder; the end of the second lifting pipe is connected with a second negative pressure cylinder; the end of the suction hose is connected with a hand pump; and the sliding pipe is connected with the force relieving and buffering protection mechanism. The delivery device adopts a double-negative-pressure-source alternate standby mechanism, and once the sucking disc falls off, the standby negative pressure source can be switched to in an instant, so that rapid re-suction is realized. Meanwhile, the delivery device has a traction force feedback buffering function, and when the traction force exceeds a threshold value, the transmission connection is automatically changed from rigidity to elasticity, so that effective force relieving is realized, and damage to the fetus and the puerpera caused by excessive traction is prevented.

Description

Technical Field

[0001] This invention belongs to the field of medical device technology, specifically referring to an obstetric delivery device. Background Technology

[0002] In obstetric clinical practice, when a mother experiences uterine atony, prolonged labor, or fetal distress during the second stage of labor, obstetric instruments are often needed to assist in the delivery of the fetus. Among these, the vacuum extractor has become one of the most widely used obstetric tools in clinical practice because it causes less damage to the birth canal compared to forceps and is relatively easier to operate. Its basic working principle is to use negative pressure suction to firmly attach the suction cup to the fetal head, and apply pulling force through the traction handle, in conjunction with the mother's uterine contractions, to pull the fetus out of the birth canal.

[0003] In existing negative pressure generation technologies, some electromechanical vacuum pumps such as piston pumps and diaphragm pumps are used as continuous negative pressure sources. Because the sealed cavity between the suction cup and the fetal head is extremely small (a tiny space), the vacuum level increases exponentially during evacuation. Limited by mechanical inertia and sensor response lag, the system struggles to achieve millisecond-level precise cutoff after reaching the preset negative pressure value. This "overshoot" phenomenon can easily lead to excessively high instantaneous negative pressure, causing fetal scalp hematoma or even intracranial injury. Another common method of negative pressure generation is the Venturi tube device designed using Bernoulli's principle. This type of device generates continuous and relatively stable negative pressure through changes in fluid flow rate. Although it is safer than electromechanical pumps and less prone to causing instantaneous extremely high negative pressure damage, in actual clinical operation, it is often difficult to establish and maintain sufficient suction force in a short time, leading to frequent occurrences of insufficient suction.

[0004] Given the shortcomings of the two methods mentioned above, the most effective and widely used method in clinical practice remains the manual vacuum pump. However, it has revealed deficiencies in actual operation: during assisted delivery, the suction cup is prone to accidental detachment due to factors such as pressure from the birth canal, changes in fetal head angle, or deviations in traction direction. Once detached, existing manual devices require multiple manual reciprocating suction operations to rebuild negative pressure. In obstetric emergencies where time is of the essence, this tedious and repetitive process wastes precious time and increases the risks to both the mother and fetus.

[0005] Meanwhile, existing manual delivery devices typically employ a rigid connection, meaning the operator applies force directly to the suction cup via a handle and traction rod. This structure lacks a mechanical feedback loop or a passive safety release mechanism. The magnitude of the traction force relies entirely on the subjective feel and experience of the medical staff. The operator is highly susceptible to applying excessive force, exceeding the tolerance limits of the fetal cervical spine or the mother's birth canal, thereby causing fetal nerve damage, fractures, or severe soft tissue lacerations in the mother. Summary of the Invention

[0006] To address the above issues, this invention provides an obstetric delivery device that employs a dual negative pressure source alternating backup mechanism. While the first negative pressure source is adsorbing, the second negative pressure source is pre-evacuated for backup. If the suction cup detaches, it can instantly switch to the backup negative pressure source for rapid re-adsorption, greatly shortening emergency response time. Simultaneously, the device has a traction force feedback buffer function. When the traction force exceeds a threshold, the transmission connection automatically changes from rigid to elastic buffer to effectively unload the force, preventing excessive traction from causing mechanical damage to the fetus and the mother.

[0007] The technical solution adopted by the present invention is as follows: The present invention proposes an obstetric delivery device, including a fetal head suction cup, a traction tube located at the rear end of the fetal head suction cup, a force relief buffer protection mechanism located at the rear end of the traction tube, and a ventilation cylinder located behind the force relief buffer protection mechanism.

[0008] Furthermore, the outer wall of the ventilation cylinder is provided with a first lifting pipe, a second lifting pipe, an air extraction hose, and a sliding pipe in a cross shape. The end of the first lifting pipe is connected to a first negative pressure cylinder, the end of the second lifting pipe is connected to a second negative pressure cylinder, the end of the air extraction hose is connected to a manual pump, and the sliding pipe is connected to a force relief buffer protection mechanism.

[0009] Furthermore, the air exchange cylinder is equipped with a directional valve; the directional valve is used to switch the internal flow channel during rotation, so that when the slide tube is connected to one of the first negative pressure cylinder and the second negative pressure cylinder to provide negative pressure to the tire head suction cup, the manual pump is operated to pre-evacuate the other connection of the first negative pressure cylinder and the second negative pressure cylinder.

[0010] Furthermore, the slide tube and the suction hose are arranged opposite each other, the second lifting tube and the first lifting tube are arranged opposite each other, the diverting valve is arranged at the same height as the inner cavity of the air exchange cylinder, the diverting valve has a rectangular plate structure, the two ends of the diverting valve are tightly fitted to the inner wall of the air exchange cylinder, and the arc surface size of the end of the diverting valve used to block the flow channel is larger than the inner diameter of the first lifting tube, the second lifting tube, the suction hose and the slide tube at the connection with the air exchange cylinder, so as to prevent crossflow when switching the flow channel.

[0011] Furthermore, the upper middle part of the directional valve is provided with a rotating shaft, which rotates coaxially through the upper wall of the air exchange cylinder. The rotating shaft is provided with a handle, which is arranged parallel to the directional valve. The surface of the air exchange cylinder is symmetrically provided with two positioning heads, which are located at the two extreme positions of the rotating stroke of the handle, respectively, to limit the movement of the directional valve.

[0012] Furthermore, when the handle is rotated to the point where it is limited by one of the positioning heads, the directional valve blocks the slide tube, which is connected only to the first lifting tube, and at the same time the second lifting tube is connected only to the suction hose; when the handle is rotated in the opposite direction to the point where it is limited by the other positioning head, the directional valve blocks the slide tube, which is connected only to the second lifting tube, and at the same time the first lifting tube is connected only to the suction hose, thereby achieving the switching of the flow channels.

[0013] Furthermore, the force-relieving buffer protection mechanism includes an expansion tube coaxially connected to the rear end of the traction tube and an extension tube coaxially connected to the rear end of the expansion tube. The front end of the slide tube is slidably sealed inside the extension tube. An electromagnet is symmetrically fixed inside the expansion tube near the end of the tire head suction cup. A drive power supply electrically connected to the electromagnet is provided outside the expansion tube.

[0014] Furthermore, a sliding shaft is symmetrically fixed at the end of the expansion tube away from the tire head suction cup. A slider is slidably sleeved on the sliding shaft. The slider is symmetrically fixed at the front end of the sliding tube. A return spring is sleeved on the sliding shaft. The return spring is located on the side of the slider away from the electromagnet. In the initial state, the slider is attracted and fixed by the electromagnet.

[0015] Furthermore, when the tension on the traction tube exceeds the attraction force threshold set by the electromagnet, the slider disengages from the electromagnet and slides backward along the sliding axis to compress the return spring; when the tension is released, the slider resets under the action of the return spring and is re-attracted by the electromagnet.

[0016] Furthermore, the manual pump is equipped with a pressure gauge, and both the first negative pressure cylinder and the second negative pressure cylinder are made of lightweight materials.

[0017] The beneficial effects achieved by the present invention using the above structure are as follows: (1) In view of the problem that existing manual pump delivery devices require repeated evacuation after the suction cup falls off, which wastes emergency time, the present invention designs a dual negative pressure source alternating backup mechanism. By switching the flow channel of the diverting valve inside the air exchange cylinder, the device can use one negative pressure cylinder to provide negative pressure adsorption for the fetal head suction cup while using the manual pump to pre-evacuate the other idle negative pressure cylinder for backup. In the event of accidental fall off, there is no need to perform the tedious manual evacuation operation again. Simply turn the handle in the opposite direction to instantly connect to the backup high vacuum negative pressure cylinder, which greatly shortens the rescue time.

[0018] (2) The present invention achieves the buffer protection function of negative pressure establishment by cooperating with the flow channel of the air exchange cylinder. When switching the negative pressure source, the end arc surface of the steering valve will slowly move away from the blockage, so that the connection area between the negative pressure cylinder and the slide tube gradually increases from small to large. This structural design makes the negative pressure not act on the fetal head instantly, but produces a gradual adsorption process, which improves the safety of the operation.

[0019] (3) This invention solves the problem of lack of mechanical feedback in the rigid connection of traditional midwifery devices. It sets up a force-relieving buffer protection mechanism based on the principle of electromagnetic adsorption. When the traction force exceeds the safety threshold set by the electromagnet, the slider will instantly break away from the electromagnet's restraint, so that the transmission connection automatically changes from rigid to elastic buffer state. At this time, the slider slides backward along the sliding axis and compresses the reset spring. The physical force relief of the mechanical structure prevents mechanical strain on the fetus and the birth canal caused by the operator's excessive force.

[0020] (4) This invention has the advantage of conforming to human biomechanics, which can ensure that the operator is not distracted during emergency treatment. When overload relief occurs, the operator's hand will move backward due to inertia and instinctively relieve the force. At this time, with the elastic force of the reset spring, the slider will be automatically pushed back to its original position and re-attached and locked by the electromagnet. The whole process does not require medical staff to take their eyes off the surgical area, nor does it require complex mechanical reset operations, thus ensuring the continuity and focus of the delivery process. Attached Figure Description

[0021] Figure 1 This is a first three-dimensional structural schematic diagram of an obstetric delivery device proposed in this invention.

[0022] Figure 2 This is a second three-dimensional structural diagram of an obstetric delivery device proposed in this invention.

[0023] Figure 3 This is a schematic diagram showing the positional relationship between the handle and the positioning head of a midwifery device for obstetric use proposed in this invention.

[0024] Figure 4 This is a schematic diagram showing the positional relationship between the steering valve and the air exchange cylinder of an obstetric delivery device proposed in this invention.

[0025] Figure 5 for Figure 2 Enlarged view of section A in the middle.

[0026] Figure 6 This is a schematic diagram of the structure of an electromagnet and a slider in an obstetric delivery device proposed in this invention.

[0027] Figure 7 This is a schematic diagram of the structure of an obstetric delivery device proposed in this invention when the electromagnet and slider are separated.

[0028] Among them, 1. Tire head suction cup, 2. Traction tube, 3. Air pump, 31. First lifting tube, 32. Second lifting tube, 33. Air extraction hose, 34. Sliding tube, 4. Force relief buffer protection mechanism, 41. Expansion tube, 42. Extension tube, 43. Electromagnet, 44. Drive power supply, 45. Slider, 46. Sliding shaft, 47. Return spring, 5. Manual pump, 51. Air pressure gauge, 6. First negative pressure cylinder, 7. Second negative pressure cylinder, 8. Steering valve, 81. Rotary shaft, 82. Handle, 83. Positioning head.

[0029] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof. Detailed Implementation

[0030] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0031] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0032] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 As shown, the present invention proposes an obstetric delivery device, the specific structure of which includes a fetal head suction cup 1, a traction tube 2 located at the rear end of the fetal head suction cup 1, a force relief buffer protection mechanism 4 located at the rear end of the traction tube 2, and an air exchange cylinder 3 located behind the force relief buffer protection mechanism 4.

[0033] As the core component of negative pressure distribution, the ventilation cylinder 3 has four interface pipes arranged in a cross-shaped circumferential array on its outer wall: a first lifting pipe 31, a second lifting pipe 32, an air extraction hose 33, and a sliding pipe 34. The sliding pipe 34 is positioned opposite to the air extraction hose 33, and the second lifting pipe 32 is positioned opposite to the first lifting pipe 31. The end of the first lifting pipe 31 is connected to the first negative pressure cylinder 6, and the end of the second lifting pipe 32 is connected to the second negative pressure cylinder 7. To reduce the operational burden on medical staff, both the first negative pressure cylinder 6 and the second negative pressure cylinder 7 are preferably made of high-strength lightweight materials (such as engineering plastics). The end of the air extraction hose 33 is connected to a manual pump 5, and a pressure gauge 51 is installed on the manual pump 5 to monitor the negative pressure value in the current circuit in real time. The sliding pipe 34 is connected to the front unloading buffer protection mechanism 4.

[0034] A diverting valve 8 is located at the center of the air exchange cylinder 3. The diverting valve 8 has a rectangular plate structure, and its height is the same as that of the inner cavity of the air exchange cylinder 3. The two ends of the diverting valve 8 are designed as arc surfaces that fit tightly against the inner wall of the air exchange cylinder 3. The size of the arc surface is larger than the inner diameter of the first lifting pipe 31, the second lifting pipe 32, the air extraction hose 33, and the slide pipe 34 at the connection with the air exchange cylinder 3. This ensures that the diverting valve 8 can completely block the corresponding pipe openings during rotation to prevent airflow. A rotating shaft 81 is fixedly connected to the middle of the upper end of the diverting valve 8. The rotating shaft 81 rotates coaxially through the upper wall of the air exchange cylinder 3 and extends to the outside. At the end, there is a handle 82 for the operator to rotate. In order to accurately control the position of the valve body, two positioning heads 83 are symmetrically provided on the surface of the air exchange cylinder 3. These two positioning heads 83 are located at the two extreme positions of the rotation stroke of the handle 82, and the rotation angle of the handle 82 can be set to 90 degrees.

[0035] The force relief buffer protection mechanism 4 is designed to provide overload protection. It includes an expansion tube 41 coaxially connected to the rear end of the traction tube 2, and an extension tube 42 coaxially connected to the rear end of the expansion tube 41. The front end of the slide tube 34 is slidably sealed inside the extension tube 42 and can be relatively displaced along the axial direction. Inside the expansion tube 41, an electromagnet 43 is symmetrically fixed at one end near the tire head suction cup 1. A drive power supply 44 (which can be a built-in battery or an external power supply) electrically connected to the electromagnet 43 is provided outside the expansion tube 41. A slide shaft 46 is symmetrically fixed at one end of the expansion tube 41 away from the tire head suction cup 1. A slider 45 is slidably sleeved on the slide shaft 46. The slider 45 is symmetrically fixed at the front end of the slide tube 34. In addition, a return spring 47 is sleeved on the slide shaft 46. The return spring 47 is located on the side of the slider 45 away from the electromagnet 43.

[0036] In the initial state, the attraction force threshold of the electromagnet 43 is set by adjusting the current of the drive power supply 44. The slider 45 is firmly attracted and fixed by the electromagnet 43. At this time, the device presents a rigid connection state and can effectively transmit traction force.

[0037] The specific work process is as follows: Pre-evacuation stage: The operator holds the air exchange cylinder 3 with one hand in a "forked grip" manner, with fingers gripping the first lifting tube 31 and the second lifting tube 32 respectively. The slide tube 34 extends out from between the fingers. The drive power supply 44 is turned on, and the attraction threshold of the electromagnet 43 is adjusted so that the slider 45 is attracted and fixed by the electromagnet 43. Then the operator rotates the handle 82 until it is limited by one of the positioning heads 83. At this time, the diverting valve 8 divides two independent flow channels inside the air exchange cylinder 3: the slide tube 34 is only connected to the first lifting tube 31 (forming the first circuit), while the second lifting tube 32 is only connected to the suction hose 33 (forming the second circuit). Another operator operates the manual pump 5 and observes the pressure gauge 51. At this time, the manual pump 5 is actually evacuating the second negative pressure cylinder 7. When the preset negative pressure value is reached, the second negative pressure cylinder 7 is in a "standby" state, storing enough vacuum energy.

[0038] During the suction-assisted delivery stage: The fetal head suction cup 1 is accurately placed over the fetal head. At this time, the first negative pressure cylinder 6 is connected to the fetal head suction cup 1 through the first lifting tube 31, the sliding tube 34, the force relief buffer protection mechanism 4, and the traction tube 2. The operator slowly rotates the handle 82 in the opposite direction. In the initial stage of rotation, the end of the steering valve 8 gradually blocks the ports of the second lifting tube 32 and the first lifting tube 31. As the rotation continues, the steering valve 8 gradually opens the passage between the first negative pressure cylinder 6 and the manual pump 5, and at the same time gradually opens the passage between the second negative pressure cylinder 7 (which has been pre-emptively depressurized) and the sliding tube 34. This process utilizes the change in the port connection area when the steering valve 8 is rotated. The process achieves a "gradual" adsorption effect. The high negative pressure in the second negative pressure cylinder 7 is not applied to the fetal head instantly, but rather a small air pressure is generated through tiny gaps for adsorption. As the handle 82 continues to rotate until it is limited by another positioning head 83, the flow channel is completely switched, and the second negative pressure cylinder 7 is fully connected to the slide tube 34, achieving stable adsorption of the fetal head. During the process of pulling the fetus outward, another medical staff member (or assistant) can operate the manual pump 5. At this time, the manual pump 5 is connected to the first lifting tube 31 and begins to pump air from the first negative pressure cylinder 6 to reach the preset negative pressure value, thereby completing the alternation of the dual negative pressure sources.

[0039] Rapid re-adsorption after accidental detachment: If the tire head suction cup 1 accidentally detaches during traction, the operator does not need to perform tedious repeated air extraction operations. Simply cover the tire head with the tire head suction cup 1 again, and then rotate the handle 82 in the opposite direction to another extreme position. At this time, the flow channel is switched again, and the first negative pressure cylinder 6, which has just been pre-evacuated, is connected to the slide tube 34 to achieve rapid re-adsorption, which greatly shortens the emergency rescue time.

[0040] Overload relief protection mechanism: During assisted delivery traction, if the operator exerts too much force, causing the tension on the traction tube 2 to exceed the attraction force threshold set by the electromagnet 43, the slider 45 will instantly break free from the electromagnet 43. According to the principle of human force exertion, when the rigid connection is suddenly broken, the operator's hand will move backward due to inertia and relieve force at this moment (i.e., involuntarily reduce the force exertion). At this time, the slider 45 slides backward along the sliding shaft 46 and compresses the return spring 47. The compression of the return spring 47 further buffers the excess kinetic energy, avoiding mechanical strain on the fetus or birth canal. When the operator senses the force relief feedback, they will instinctively stop exerting force. At this time, under the elastic force of the return spring 47, the slider 45 is pushed back to its original position and is attracted by the electromagnet 43 again. The device automatically returns to the working state for the next traction operation.

[0041] It should be noted that, in this document, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0042] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention.

[0043] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention; the actual structure is not limited thereto. In conclusion, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the spirit of the invention, such designs should fall within the protection scope of the present invention.

Claims

1. An obstetric delivery device, comprising a fetal head suction cup (1), characterized in that: It also includes a traction tube (2) located at the rear end of the tire head suction cup (1), a force relief buffer protection mechanism (4) located at the rear end of the traction tube (2), and an air exchange cylinder (3) located behind the force relief buffer protection mechanism (4). The outer wall of the air exchange cylinder (3) is provided with a first lifting pipe (31), a second lifting pipe (32), an air extraction hose (33), and a sliding pipe (34) in a cross shape. The end of the first lifting pipe (31) is connected to a first negative pressure cylinder (6), the end of the second lifting pipe (32) is connected to a second negative pressure cylinder (7), the end of the air extraction hose (33) is connected to a manual pump (5), and the sliding pipe (34) is connected to a force relief buffer protection mechanism (4). The air exchange cylinder (3) is equipped with a directional valve (8); the directional valve (8) is used to switch the internal flow channel during rotation, so that when the slide tube (34) is connected to one of the first negative pressure cylinder (6) and the second negative pressure cylinder (7) to provide negative pressure to the tire head suction cup (1), the manual pump (5) is operated to pre-evacuate the other connection of the first negative pressure cylinder (6) and the second negative pressure cylinder (7); The slide tube (34) is arranged opposite to the suction hose (33), the second lifting tube (32) is arranged opposite to the first lifting tube (31), the diverting valve (8) is arranged at the same height as the inner cavity of the air exchange cylinder (3), the diverting valve (8) has a rectangular plate structure, the two end faces of the diverting valve (8) are tightly fitted with the inner wall of the air exchange cylinder (3), and the arc surface size of the end of the diverting valve (8) used to block the flow channel is larger than the inner diameter of the first lifting tube (31), the second lifting tube (32), the suction hose (33) and the slide tube (34) at the connection with the air exchange cylinder (3); The unloading buffer protection mechanism (4) includes an expansion tube (41) coaxially connected to the rear end of the traction tube (2) and an extension tube (42) coaxially connected to the rear end of the expansion tube (41). The front end of the slide tube (34) is slidably sealed inside the extension tube (42). An electromagnet (43) is symmetrically fixed inside the expansion tube (41) at one end near the tire head suction cup (1). A drive power supply (44) electrically connected to the electromagnet (43) is provided outside the expansion tube (41). The expansion tube (41) has a sliding shaft (46) symmetrically fixed at one end away from the tire head suction cup (1). A slider (45) is slidably sleeved on the sliding shaft (46). The slider (45) is symmetrically fixed at the front end of the slide tube (34). A return spring (47) is sleeved on the sliding shaft (46). The return spring (47) is located on the side of the slider (45) away from the electromagnet (43). In the initial state, the slider (45) is attracted and fixed by the electromagnet (43).

2. The obstetric delivery device according to claim 1, characterized in that: The upper middle part of the steering valve (8) is provided with a rotating shaft (81). The rotating shaft (81) rotates coaxially through the upper wall of the air exchange cylinder (3). The rotating shaft (81) is provided with a handle (82). The handle (82) is arranged parallel to the steering valve (8). The surface of the air exchange cylinder (3) is symmetrically provided with two positioning heads (83). The two positioning heads (83) are located at the two extreme positions of the rotation stroke of the handle (82).

3. The obstetric delivery device according to claim 2, characterized in that: When the handle (82) is rotated to the point where it is limited by one of the positioning heads (83), the slide tube (34) is connected to the first lifting tube (31) only through the obstruction of the directional valve (8), and at the same time the second lifting tube (32) is connected to the suction hose (33) only. When the handle (82) is rotated in the opposite direction to the point where it is limited by the other positioning head (83), the slide tube (34) is connected to the second lifting tube (32) only through the obstruction of the directional valve (8), and at the same time the first lifting tube (31) is connected to the suction hose (33) only.

4. The obstetric delivery device according to claim 3, characterized in that: When the pulling force on the traction tube (2) exceeds the adsorption force threshold set by the electromagnet (43), the slider (45) disengages from the electromagnet (43) and slides backward along the sliding shaft (46) to compress the reset spring (47); when the pulling force is released, the slider (45) resets under the action of the reset spring (47) and is re-adsorbed by the electromagnet (43).

5. The obstetric delivery device according to claim 4, characterized in that: The manual pump (5) is equipped with a pressure gauge (51), and the first negative pressure cylinder (6) and the second negative pressure cylinder (7) are both made of lightweight materials.

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