A breast pump
Patent Information
- Application Number
- CN202522348261.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-05
- Publication Date
- 2026-10-13
- Estimated Expiration
- 2035-11-05
AI Technical Summary
[0004]本实用新型针对上述提到的现有吸乳器在乳罩中设置按摩器,但因乳罩的频繁清洗消毒,容易造成按摩器短路失效的问题,提出一种更加安全稳定的吸乳器
1、相比于现有的振动按摩头安装在乳罩的方式,本实用新型通过将振动机构设置在机壳上,能够避免乳房罩频繁清洗消毒而导致振动机构容易短路失效,进而提升振动机构的稳定性和可靠性,延长吸乳器的使用寿命,而且,实际生产时可直接对机壳进行改造即可,降低了传统吸乳器的改造成本,提升了吸乳器主机对不同乳房罩的适配性。
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Figure CN224845636U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of breast pumps, and more particularly to a breast pump. Background Technology
[0002] A breast pump is a tool that helps breastfeeding women express milk by mimicking the natural sucking motion of an infant. Breast pumps are generally equipped with a bra to fit the breast. To enhance the efficiency of milk expression and relieve breast discomfort, some breast pumps on the market include a massager within the bra to reinforce the mimicking of an infant's sucking motion. However, in daily life, because the bra often needs to be removed for cleaning and sterilization, this can easily cause the massager to short-circuit and malfunction.
[0003] This utility model was proposed in response to the shortcomings of the existing technology. Utility Model Content
[0004] This invention addresses the problem mentioned above where existing breast pumps incorporate massagers within the bra, but frequent cleaning and disinfection of the bra can easily cause the massagers to short-circuit and fail. The invention proposes a safer and more stable breast pump.
[0005] The technical solution adopted by this utility model to solve its technical problem is: A breast pump includes a housing, a milk storage container, a breast shield disposed on one side of the housing, and a vibration mechanism disposed on the housing. The breast shield includes a milk suction channel and a fitting part that contacts the breast. The vibration mechanism includes at least one vibration part, which includes a massage head base disposed on the housing and a vibrator disposed on the massage head base. The massage head base is integrally formed with the housing and abuts against the fitting part, thereby transmitting the vibration energy output by the vibrator to the fitting part through the massage head base.
[0006] As described above, in a breast pump, the massage head base has a receiving cavity for accommodating the vibrator, and a first limiting part for fixing the vibrator is provided on one side of the receiving cavity. The first limiting part has an opening communicating with the receiving cavity.
[0007] As described above, the breast pump has a peripheral portion on the outer side of the massage head base that connects to the housing.
[0008] As described above, the peripheral portion of the breast pump includes a first connecting portion disposed on the outer periphery of the massage head base and a second connecting portion disposed on the outer periphery of the first connecting portion. The first connecting portion and the second connecting portion have a preset included angle, and the second connecting portion is connected to the housing.
[0009] As described above, in one type of breast pump, the massage head base is made of a soft material, and the housing is made of a hard material.
[0010] As described above, the vibrator is a miniature vibration motor, and the breast pump also includes a control board. The miniature vibration motor is electrically connected to the control board, and the control board is equipped with a power interface.
[0011] As described above, a breast pump has a plurality of vibrating parts, which are distributed circumferentially around the breast pumping channel.
[0012] As described above, in a breast pump, the housing is disposed between the breast shield and the milk storage container. The housing has a through hole for mounting. One end of the breast shield passes through the through hole and is connected to the milk storage container. The milk suction channel extends into the milk storage container and communicates with the inner cavity of the milk storage container. The housing is provided with a negative pressure mechanism that communicates with the milk suction channel, and the negative pressure mechanism generates negative pressure in the milk suction channel.
[0013] As described above, in a breast pump, the milk storage container has a first assembly portion for connecting the housing and the milk storage container. The first assembly portion at least partially protrudes outside the milk storage container and connects to the mounting through hole. The breast shield has a second assembly portion corresponding to and connected to the first assembly portion. The housing also has a second limiting portion extending radially into the mounting through hole, and a clamping cavity for clamping the second assembly portion is formed between the second limiting portion and the first assembly portion. The breast shield also has a first groove corresponding to the second limiting portion. A protrusion is provided between the first assembly portion and the second assembly portion.
[0014] As described above, the breast pump housing is further provided with at least one mounting cavity communicating with the mounting through hole. The mounting cavity is provided with a locking member, which has a retractable locking end. The first assembly part is provided with a second groove corresponding to the locking end.
[0015] Compared with the prior art, the beneficial effects of this utility model are: 1. Compared with the existing method of installing the vibration massage head on the bra, this utility model sets the vibration mechanism on the housing, which can avoid the vibration mechanism from being easily short-circuited and failing due to frequent cleaning and disinfection of the bra. This improves the stability and reliability of the vibration mechanism, extends the service life of the breast pump, and allows for direct modification of the housing during actual production, reducing the modification cost of traditional breast pumps and improving the compatibility of the breast pump main unit with different bras.
[0016] 2. The massage head base and the housing are integrally molded, which simplifies the assembly steps of the breast pump. During assembly, the vibrator can be directly installed on the massage head base, which helps to improve the production and assembly efficiency of the breast pump. Moreover, the integral molding process can avoid the assembly gap between the massage head base and the housing, which helps to enhance the sealing of the housing and thus protect the breast pump.
[0017] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Attached Figure Description
[0018] Figure 1 This is a perspective view of the breast pump of this utility model; Figure 2 Disassembly of the breast pump of this utility model Figure 1 ; Figure 3 Disassembly of the breast pump of this utility model Figure 2 ; Figure 4 Disassembly of the breast pump of this utility model Figure 3 ; Figure 5 Disassembly of the breast pump of this utility model Figure 4 ; Figure 6 This is a front view of the breast pump of this utility model (with the breast shield and milk storage container hidden). Figure 7 for Figure 6 Sectional view A-A in the middle; Figure 8 for Figure 7 Enlarged view of part B in the image; Figure 9 for Figure 6 The C-C section view in the image. Detailed Implementation
[0019] The embodiments of this utility model will now be described in detail with reference to the accompanying drawings. The described embodiments are merely some, not all, of the embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model.
[0020] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.
[0021] Furthermore, the use of terms such as "first" and "second" in this utility model is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this utility model.
[0022] like Figures 1 to 9 As shown, this utility model provides a breast pump, including a housing 1, a milk storage container 5, a breast shield 2 disposed on one side of the housing 1, and a vibration mechanism disposed on the housing 1. The breast shield 2 includes a milk suction channel 21 and a fitting part 22 that contacts the breast. The vibration mechanism includes at least one vibration part 31. The vibration part 31 includes a massage head base 312 disposed on the housing 1 and a vibrator 313 disposed on the massage head base 312. The massage head base 312 is integrally formed with the housing 1, and the massage head base 312 abuts against the fitting part 22. The vibration energy output by the vibrator 313 is transmitted to the fitting part 22 through the massage head base 312.
[0023] In this invention, the housing 1 can be used as the housing of the breast pump main unit. Compared with the existing method of mounting the vibrating massage head on the bra, this invention, by setting the vibration mechanism on the housing 1, can avoid the frequent cleaning and disinfection of the bra 2, which can easily cause the vibration mechanism to short-circuit and fail. This improves the stability and reliability of the vibration mechanism, extends the service life of the breast pump, and allows for direct modification of the housing 1 during actual production, reducing the modification cost of traditional breast pumps and improving the adaptability of the breast pump main unit to different bras 2. Secondly, the massage head base 312 is integrally formed with the housing 1, simplifying the assembly steps of the breast pump. During assembly, the vibrator 313 can be directly installed on the massage head base 312, which helps to improve the production and assembly efficiency of the breast pump. Moreover, the integral forming process can avoid the assembly gap between the massage head base 312 and the housing 1, which helps to enhance the sealing of the housing 1 and protect the electrical mechanism and other functional modules inside the housing 1, thereby achieving the purpose of protecting the breast pump.
[0024] In practical applications, the breast bra 2 is attached to the human breast through the fitting part 22. The vibration mechanism is set on the housing 1 and is in contact with the breast bra 2. The vibration mechanism drives the breast bra 2 to vibrate, so as to realize the vibration massage of the breast of the breastfeeding woman, promote the lactation reflex of the breastfeeding woman, improve the milk pumping efficiency, and at the same time relieve breast discomfort and pain, thus improving the breast pumping experience of the breastfeeding woman.
[0025] Further optionally, the breast bra 2 can be configured as a trumpet-shaped bra or a bowl-shaped bra, etc., without specific limitation here. The breast bra 2 can be made of soft materials such as silicone or rubber. The fitting part 22 at least partially abuts against the massage head base 312 so as to transmit the vibration force output by the vibrator 313 to the human body through the massage head base 312 and the fitting part 22.
[0026] Furthermore, as an optional embodiment of this solution, such as Figure 8 As shown, the massage head base 312 is further provided with a receiving cavity 3121 for accommodating the vibrator 313. A first limiting part 3122 for fixing the vibrator 313 is provided on one side of the receiving cavity 3121. The first limiting part 3122 is provided with an opening 3123 communicating with the receiving cavity 3121. Specifically, the housing 1 is provided with an inner cavity. The receiving cavity 3121 is provided on the side of the massage head base 312 facing the inner cavity of the housing 1. The receiving cavity 3121 communicates with the inner cavity of the housing 1 through the opening 3123. The receiving cavity 3121 is adapted to the vibrator 313. The vibrator 313 is clamped and fixed by the inner wall of the receiving cavity 3121 and the first limiting part 3122, so as to improve the connection tightness between the vibrator 313 and the massage head base 312, thereby improving the vibration transmission efficiency of the massage head base 312.
[0027] Furthermore, as an optional embodiment of this solution, such as Figure 8 As shown, the outer side of the massage head base 312 is also provided with a peripheral portion 3124 that connects to the housing 1. By adjusting the thickness of the peripheral portion 3124, the lightweight of the connection structure between the massage head base 312 and the housing 1 can be enhanced to a certain extent, thereby reducing the vibration resistance of the massage head base 312, improving the vibration transmission efficiency of the massage head base 312, and enhancing the vibration massage effect experienced by the user. At the same time, the peripheral portion 3124 can buffer the vibration impact force received by the housing 1, thereby protecting the housing 1.
[0028] Optional, such as Figure 8As shown, the peripheral portion 3124 includes a first connecting portion 3124a disposed on the outer periphery of the massage head base 312 and a second connecting portion 3124b disposed on the outer periphery of the first connecting portion 3124a. A preset angle is formed between the first connecting portion 3124a and the second connecting portion 3124b. The second connecting portion 3124b is connected to the housing 1. Optionally, the first connecting portion 3124a may extend approximately radially outward along the massage head base 312, and the second connecting portion 3124b extends from the first connecting portion 3124a. The edge of 124a extends along the axial direction of the massage head base 312. The first connecting part 3124a and the second connecting part 3124b can form an L-shaped peripheral part or a T-shaped peripheral part, which is not specifically limited here. By setting the peripheral part 3124, the connection strength and tightness between the massage head base 312 and the housing 1 can be improved, and the vibration transmission efficiency of the massage head base 312 can be improved. The peripheral part 3124 can be integrally formed with the massage head base 312. The peripheral part 3124 has a simple structure and is easy to form.
[0029] Furthermore, as an optional embodiment of this solution, the massage head base 312 is made of a soft material, and the housing 1 is made of a hard material; optionally, the massage head base 312 can be made of soft materials such as silicone, rubber, TPE, etc., and the housing 1 can be made of hard materials such as ABS plastic, PC plastic, or PP plastic; in actual production, the massage head base 312 and the housing 1 are integrally injection molded through a rubber coating process to simplify the production and assembly process of the breast pump. Moreover, since the massage head base 312 has a certain degree of elasticity, the vibrator 313 can be directly snapped into the receiving cavity 3121 during assembly, which facilitates the disassembly and assembly of the vibrator 313.
[0030] Furthermore, as an optional embodiment of this solution, such as Figure 4 and Figure 5 As shown, the vibrator 313 is a miniature vibration motor, and the breast pump also includes a control board 4. The miniature vibration motor is electrically connected to the control board 4, and the control board 4 is equipped with a power interface 41. By using a miniature vibration motor, the size and weight of the vibrator 313 can be reduced, thereby reducing the size and weight of the breast pump and optimizing the user experience. On the other hand, the control board 4 is used to supply power to the vibrator 313 and control its operation. The miniature vibration motor is snapped into the receiving cavity 3121 and electrically connected to the control board 4 through a wire. The opening 3123 not only provides an assembly port for the miniature vibration motor but also allows for wire routing to ensure the electrical connection between the vibrator 313 and the control board 4.
[0031] Alternatively, the control board 4 can be configured to be plugged in or recharged, and can be powered by an external power source connected to the power interface 41. The power interface 41 can be configured as a plug power cord, USB interface or Type interface, etc., without specific limitations.
[0032] Optionally, the breast pump also includes a battery that can be electrically connected to the control board 4 to enable the control board 4 to charge and supply power. Alternatively, the breast pump can also be equipped with a charging board that can be set to charge independently or in coordination with the control board 4, and the charging board is electrically connected to the battery. In practical applications, the breast pump can be used while rechargeable, which improves the flexibility and convenience of the breast pump, makes it easier for users to carry the breast pump when going out, and optimizes the user experience.
[0033] Furthermore, as an optional embodiment of this solution, such as Figure 7 As shown, there are several vibration parts 31, and each vibration part 31 is distributed circumferentially around the milk suction channel 21 to facilitate vibration massage of the breast from multiple directions and positions, further enhancing the vibration massage effect of the vibration mechanism on the human breast and improving milk suction efficiency; Optionally, in practical applications, each vibration part 31 can be fitted to the lower part of the human breast, that is, when milk is being sucked, each vibration part 31 is fitted to the base of the human breast.
[0034] On the other hand, to make it easier for users to assemble and disassemble the breast pump, Figure 9 Another optional embodiment of the breast pump is also shown, wherein the housing 1 is disposed between the breast shield 2 and the milk storage container 5, the housing 1 is provided with a mounting hole 12, one end of the breast shield 2 passes through the mounting hole 12 and is connected to the milk storage container 5, the housing 1 is disposed between the breast shield 2 and the milk storage container 5, and the breast shield 2 and the milk storage container 5 clamp the housing 1, the milk suction channel 21 extends into the milk storage container 5 and communicates with the inner cavity 51 of the milk storage container, the housing 1 is provided with a negative pressure mechanism 6 communicating with the milk suction channel 21, the control board 4 is electrically connected to the negative pressure mechanism 6, the control board 4 controls the operation of the negative pressure mechanism 6, and the negative pressure mechanism 6 directly or indirectly generates negative pressure in the milk suction channel 21, so that the breast shield 2 can realize the simulated breastfeeding action to promote the output of breast milk, and guide the breast milk to the inner cavity 51 of the milk storage container through the milk suction channel 21.
[0035] Further optional, such as Figure 9As shown, the milk storage container 5 is provided with a first assembly part 53 for connecting the housing 1 and the milk storage container 5. The first assembly part 53 at least partially protrudes to the outside of the milk storage container 5 and connects to the mounting through hole 12. The breast bra 2 is provided with a second assembly part 23 corresponding to and connected to the first assembly part 53. The housing 1 is also provided with a second limiting part 13 extending radially into the mounting through hole 12. A clamping cavity 7 is formed between the second limiting part 13 and the first assembly part 53 to clamp the second assembly part 23. The breast bra 2 is also provided with a first groove 231 corresponding to the second limiting part 13. Specifically, The first assembly part 53 is disposed in the milk storage container 5 and is used to connect the breast shield 2 and the housing 1. The first assembly part 53 protrudes at least partially toward the outer side of the milk storage container 5 in the direction of the housing 1, and the protruding part of the first assembly part 53 is adapted to and engaged with the second assembly part 23 and the inner wall of the mounting through hole 12, so as to facilitate the user to disassemble and assemble the breast pump. At the same time, the second limiting part 13 is engaged in the first groove 231 to improve the connection stability and sealing of the housing 1 and the breast shield 2, prevent the breast shield 2 from easily falling off due to changes in the internal pressure of the milk pumping channel 21, and prevent the breast pump from leaking air, thereby ensuring the normal milk pumping of the user.
[0036] Optionally, the second limiting part 13 and the inner wall of the mounting through hole 12 combine to form an L-shaped end face, through which the first assembly part 53 is fixed. The inner side of the first assembly part 53 is also provided with a positioning step, which is opposite to the second limiting part 13, so that the clamping cavity 7 is formed between the positioning step and the second limiting part 13. When the second assembly part 23 is engaged in the first assembly part 53, the second assembly part 23 can be clamped by the second limiting part 13 and the positioning step, so as to improve the structural stability and reliability of the breast pump. The breast pumping channel 21 extends through the first assembly part 53 into the milk storage container 5 and communicates with the inner cavity 51 of the milk storage container.
[0037] Furthermore, such as Figure 9 As shown, the second assembly part 23 extends at least partially into the clamping cavity 7 to form a reinforcing part 232, such that the first groove 231 is formed between the reinforcing part 232 and the fitting part 22. The reinforcing part 232 is located outside the second assembly part 23 and is fixed by the second limiting part 13 and the positioning step, so as to increase the snap-fit area between the first assembly part 53 and the second assembly part 23, and further improve the connection stability and sealing between the breast bra 2 and the milk storage container 5.
[0038] Optionally, to further enhance the connection stability and sealing between the breast bra 2 and the milk storage container 5, a protrusion 233 is provided between the first assembly part 53 and the second assembly part 23; the protrusion 233 can be provided on the inner wall of the first assembly 53 or on the outer wall of the second assembly part 23, without specific limitation here; the protrusion 233 can close the assembly gap between the first assembly part 53 and the second assembly part 23, thereby enhancing the assembly pre-tightening force and connection sealing between the first assembly part 53 and the second assembly part 23; preferably, the second assembly part 23, the protrusion 233 and the breast bra 2 are integrally formed.
[0039] Alternatively, the protrusion 233 may be disposed between the first mounting portion 53 and the reinforcing portion 232.
[0040] During assembly, the housing 1 can be first fitted onto the outside of the breast bra 2, and the second limiting part 13 can be engaged in the first groove 231. At the same time, a clamping space for clamping the first assembly part 53 is formed between the second assembly part 23 and the housing 1. This clamping space is part of the mounting through hole 12. Subsequently, the milk storage container 5 can be engaged in the clamping space through the first assembly part 53 to achieve the snap-fit assembly of the breast bra 2, the housing 1 and the milk storage container 5. The structure is simple and easy to disassemble and assemble.
[0041] To further improve the connection stability of the breast pump Figure 9 Another optional embodiment of the breast pump is also shown, wherein the housing 1 is further provided with at least one mounting cavity 14 communicating with the mounting through hole 12, and a locking member 15 is provided in the mounting cavity 14. The locking member 15 is fixedly installed in the mounting cavity 14, and the locking member 15 has a retractable locking end 151. The first assembly part 53 is provided with a second groove 531 corresponding to the locking end 151. Optionally, the locking member 15 can be configured as an elastic positioning bead assembly, a bead assembly, etc., with elastic elements, and is not specifically limited here. The outer wall of the protruding part of the first assembly part 53 is provided with the second groove 531. The locking element 15 is correspondingly provided with the second groove 531. When the milk storage container 5 is connected to the housing 1, the locking end 151 can be retracted into the main body of the locking element 15 under external force to improve the smoothness of the first assembly part 53 in the mounting through hole 12 and avoid jamming. When the locking end 151 is opposite to the second groove 531, the locking end 151 automatically extends to the outside of the locking element 15 under elastic force and is locked in the second groove 531 to further improve the connection stability between the milk storage container 5 and the housing 1, thereby improving the connection stability of the breast pump and making the breast pumping process safer and more reliable.
[0042] Optionally, at least two locking members 15 are provided, and the two locking members 15 are distributed circumferentially along the mounting through hole 12, and the second groove 531 is adjusted according to the locking members 15. Preferably, the two locking members 15 are symmetrically arranged in the housing 1.
[0043] The above examples are merely illustrative of the technical content of this utility model to facilitate reader understanding, but do not imply that the implementation of this utility model is limited to these embodiments. Any technical extensions or re-creations made based on this utility model are protected by this utility model. The scope of protection of this utility model is defined by the claims.
Claims
1. A breast pump, characterized in that, It includes a housing (1), a milk storage container (5), a breast shield (2) disposed on one side of the housing (1), and a vibration mechanism disposed on the housing (1). The breast shield (2) includes a milk suction channel (21) and a fitting part (22) that contacts the breast. The vibration mechanism includes at least one vibration part (31), the vibration part (31) includes a massage head base (312) disposed on the housing (1) and a vibrator (313) disposed on the massage head base (312). The massage head base (312) is integrally formed with the housing (1), and the massage head base (312) abuts against the fitting part (22). The vibration energy output by the vibrator (313) is transmitted to the fitting part (22) through the massage head base (312).
2. A breast pump as described in claim 1, characterized in that, The massage head base (312) is provided with a receiving cavity (3121) for accommodating the vibrator (313). A first limiting part (3122) for fixing the vibrator (313) is provided on one side of the receiving cavity (3121). An opening (3123) communicating with the receiving cavity (3121) is provided in the first limiting part (3122).
3. A breast pump as described in claim 1, characterized in that, The outer side of the massage head base (312) is also provided with a peripheral part (3124) that connects to the housing (1).
4. A breast pump as described in claim 3, characterized in that, The peripheral portion (3124) includes a first connecting portion (3124a) disposed on the outer periphery of the massage head base (312) and a second connecting portion (3124b) disposed on the outer periphery of the first connecting portion (3124a). The first connecting portion (3124a) and the second connecting portion (3124b) have a preset included angle, and are connected to the housing (1) through the second connecting portion (3124b).
5. A breast pump as described in claim 1, characterized in that, The massage head base (312) is made of soft material, and the housing (1) is made of hard material.
6. A breast pump as described in claim 1, characterized in that, The vibrator (313) is a miniature vibration motor. The breast pump also includes a control board (4). The miniature vibration motor is electrically connected to the control board (4). The control board (4) is equipped with a power interface (41).
7. A breast pump as described in claim 1, characterized in that, The vibrating part (31) is provided in a plurality of units, and each of the vibrating parts (31) is distributed circumferentially around the milk suction channel (21).
8. A breast pump as described in any one of claims 1 to 7, characterized in that, The housing (1) is located between the breast bra (2) and the milk storage container (5). The housing (1) has a through hole (12). One end of the breast bra (2) passes through the through hole (12) and is connected to the milk storage container (5). The milk suction channel (21) extends into the milk storage container (5) and communicates with the inner cavity (51) of the milk storage container. The housing (1) is provided with a negative pressure mechanism (6) that communicates with the milk suction channel (21). The negative pressure mechanism (6) generates negative pressure in the milk suction channel (21).
9. A breast pump as described in claim 8, characterized in that, The milk storage container (5) is provided with a first assembly part (53) for connecting the housing (1) and the milk storage container (5). The first assembly part (53) protrudes at least partially to the outside of the milk storage container (5) and is connected to the mounting through hole (12). The breast shield (2) is provided with a second assembly part (23) corresponding to and connected to the first assembly part (53). The housing (1) is also provided with a second limiting part (13) extending radially into the mounting through hole (12). A clamping cavity (7) is formed between the second limiting part (13) and the first assembly part (53) to clamp the second assembly part (23). The bra (2) is also provided with a first groove (231) corresponding to the second limiting part (13); A protrusion (233) is provided between the first assembly part (53) and the second assembly part (23).
10. A breast pump as described in claim 9, characterized in that, The housing (1) is also provided with at least one mounting cavity (14) communicating with the mounting through hole (12). The mounting cavity (14) is provided with a locking member (15). The locking member (15) has a retractable locking end (151). The first assembly part (53) is provided with a second groove (531) corresponding to the locking end (151).