Frequency converter

Abstract

The utility model provides a frequency converter, which comprises a main body part, the main body part comprises a lower shell and a control circuit board, the control circuit board is arranged on the lower shell, the control circuit board is integrated with an electronic component and a wiring terminal, and the wiring terminal is provided with a wiring part; the upper shell comprises a cover body and a wiring cover, the cover body is connected to the lower shell, the electronic component is packaged in a first packaging part formed by the lower shell and the cover body, the cover body is provided with an avoiding opening, at least the wiring part of the wiring terminal penetrates out of the avoiding opening and is exposed out of the cover body, and the wiring cover is connected to the cover body. And the wiring terminal is packaged in a second packaging part formed by the wiring cover and the cover body, and the second packaging part is provided with a wire passing port through which a connecting wire harness passes. According to the utility model, the upper shell is arranged as a split structure of the cover body and the wiring cover, during assembly, the cover body is firstly connected to the lower shell, then wiring operation is carried out, finally the wiring cover is connected, and a wiring part is exposed out of the cover body during wiring, so that the visual performance is strong, the operation space is not limited, wiring is convenient and rapid, and the wiring accuracy and efficiency are improved.

Description

Technical Field

[0001] The present application relates to the technical field of frequency converters, and in particular to a frequency converter. Background Art

[0002] The inverter has the characteristics of saving energy, improving system efficiency, and fast switching speed. It usually includes a shell and a control circuit board arranged inside the shell. The control circuit board is integrated with wiring terminals. The shell is provided with a wire hole at a position corresponding to the wiring terminal. The connecting wire harness passes through the wire hole from the outside to the inside and is fastened to the wiring terminal by bolts to realize the external output of the inverter. However, the existing traditional solution is not convenient for wiring personnel to connect quickly and accurately because the operation space is limited during wiring.

[0003] Therefore, how to provide a frequency converter with convenient and fast wiring and improve wiring accuracy and efficiency is a technical problem that technical personnel in this field urgently need to solve. Utility Model Content

[0004] The purpose of this application is to provide a frequency converter with convenient and fast wiring, and to improve wiring accuracy and efficiency.

[0005] In order to solve the above technical problems, the present application provides a frequency converter, comprising:

[0006] A main body, the main body comprising a lower shell and a control circuit board, the control circuit board is mounted on the lower shell, the control circuit board is integrated with electronic components and wiring terminals, and the wiring terminals have wiring parts;

[0007] The upper housing comprises a cover and a wiring cover, the cover is connected to the lower housing, the cover and the lower housing form a first packaging part, the electronic components are packaged inside the first packaging part, the cover has a avoidance opening, at least the wiring part of the wiring terminal passes through the avoidance opening and is exposed on the cover,

[0008] The wiring cover is connected to the cover body, and the wiring cover and the cover body form a second packaging part. The wiring terminals are packaged inside the second packaging part. The second packaging part is provided with a wire passing port, and the wire passing port is configured for connecting a wire harness to pass through.

[0009] The utility model frequency converter changes the shell structure of the traditional frequency converter. The upper shell is set as a split structure of a cover body and a wiring cover. When assembling, the cover body is first connected to the lower shell, and the electronic components are encapsulated in the first encapsulation part formed by the lower shell and the cover body, so that the protection of the electronic components is reliable and meets the required grade requirements; and at least the wiring part of the wiring terminal passes through the avoidance port and is exposed to the cover body. At this time, the wiring operation can be carried out. Since the wiring part of the wiring terminal is exposed to the cover body, the wiring personnel can observe the position of the wiring part without any obstacles, and the cover body will not interfere with the wiring operation. The wiring personnel do not need to blindly connect, the visuality is strong, the operating space is not limited, the operability is strong, the wiring is convenient and fast, and the wiring accuracy and efficiency of the wiring personnel are improved. After completing the wiring operation, the wiring cover is connected to the cover body, and the wiring terminal is encapsulated in the second encapsulation part formed by the wiring cover and the cover body, so that the protection of the electronic components is reliable and meets the required grade requirements. At the same time, the second encapsulation part is also provided with a wire passing port to avoid the connection harness, so that the wiring cover and the connection harness do not interfere with each other, and the wiring cover is reliably installed.

[0010] Optionally, the wiring terminals pass through the avoidance opening one by one, and the wiring portion faces the upper end.

[0011] The outer wall of the cover body has a baffle portion arranged along the circumference corresponding to the avoidance opening, the baffle portion is provided with a first notch portion, the first notch portion penetrates the upper end wall of the baffle portion, the baffle portion forms a partial structure of the second packaging portion, and the first notch portion participates in forming the wire passing opening.

[0012] Optionally, the wiring cover includes an upper cover portion, the upper cover portion is connected above the barrier portion, the lower side wall of the upper cover portion is in contact with or has a spacing with the corresponding upper side wall of the barrier portion, and the upper cover portion forms a partial structure of the second packaging portion.

[0013] Optionally, the wiring cover also includes a folding portion, which is connected to the upper cover portion and extends downward, and the folding portion is provided with a second notch portion, the second notch portion is connected to the corresponding first notch portion, and the second notch portion participates in forming the avoidance opening.

[0014] Optionally, the wiring cover further includes a reinforcing plate, and the reinforcing plate is connected between the upper cover portion and the folding portion.

[0015] Optionally, the cover body is provided with a supporting portion, and when the upper cover portion is connected to the cover body, the lower side wall of the upper cover portion is supported on the upper side wall of the supporting portion.

[0016] Optionally, the inverter has at least one wiring area, and the wiring terminals located in the same wiring area are distributed in sequence to form a row, and the wiring terminals in the same wiring area are located inside the second packaging part formed by the same wiring cover and the cover body.

[0017] Optionally, one of the wiring cover and the cover body is provided with a buckle, and the other is provided with a snap-fit ​​hole, and the snap-fit ​​portion of the buckle is snap-fitted into the corresponding snap-fit ​​hole.

[0018] Optionally, the frequency converter has at least one wiring area, and the wiring terminals located in the same wiring area are sequentially distributed to form a row, and the wiring terminals in the same wiring area are located inside the second packaging portion formed by the same wiring cover and the cover body;

[0019] The two ends of the wiring cover are connected with the clips, the outer wall of the cover body has two extension parts extending upward, the extension parts are located at the two ends of the same wiring area, the extension parts are provided with the clip holes, and the clip parts of the clips at the same end are clipped into the corresponding clip holes.

[0020] Optionally, the buckle includes a connecting portion extending downward, the clamping portion is located at a lower end of the connecting portion and extends in a direction close to the extending portion, and there is a distance between the connecting portion and the extending portion. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic structural diagram of a specific embodiment of the frequency converter provided by the utility model;

[0022] Figure 2 for Figure 1 Schematic diagram of the structure of the main part of the inverter;

[0023] Figure 3 for Figure 1 Schematic diagram of the structure of the cover in the inverter;

[0024] Figure 4 for Figure 1 Split diagram of the inverter;

[0025] Figure 5 for Figure 1 One of the state diagrams of the inverter during wiring;

[0026] Figure 6 for Figure 1 The schematic diagram of the structure of the inverter from the second angle;

[0027] Figure 7 for Figure 1 Schematic diagram of the structure of the wiring cover in the inverter;

[0028] Figure 8 for Figure 1 The third perspective structural diagram of the inverter;

[0029] in, Figure 1-Figure 8 The reference numerals in the figures are as follows:

[0030] 1-lower housing;

[0031] 2-control circuit board; 21-electronic components; 22-connection terminals; 22a-connection part;

[0032] 3-cover body; a-avoidance opening; 31-blocking portion; 31a-first notch portion; 3A-cover body; A-first side wall; 3B-flat portion; 3C-blocking member; 32-supporting portion; 33-extending portion; 3a-clamping hole;

[0033] 4-wiring cover; 41-upper cover; 42-folding portion; 42a-second notch portion; 43-reinforcement plate; 4a-buckle; 4a1-clamping portion; 4a2-connecting portion;

[0034] b-line crossing;

[0035] 01- Connect the wiring harness. DETAILED DESCRIPTION

[0036] In order to enable those skilled in the art to better understand the technical solution of the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0037] In this article, the direction toward the middle of the inverter is "inside" and the direction away from the middle of the inverter is "outside".

[0038] Please refer to Figure 1-Figure 5 , Figure 1 A schematic diagram of the structure of a specific embodiment of the frequency converter provided by the utility model; Figure 2 for Figure 1 Schematic diagram of the structure of the main part of the inverter; Figure 3 for Figure 1 Schematic diagram of the structure of the cover in the inverter; Figure 4 for Figure 1 Split diagram of the inverter; Figure 5 for Figure 1 One of the status diagrams of the inverter during wiring.

[0039] The utility model provides a frequency converter, comprising:

[0040] The main body includes a lower shell 1 and a control circuit board 2. The control circuit board 2 is installed on the lower shell 1. The control circuit board 2 is integrated with electronic components 21 and a connection terminal 22. The connection terminal 22 has a connection portion 22a.

[0041] The upper housing comprises a cover 3 and a wiring cover 4. The cover 3 is connected to the lower housing 1. The cover 3 and the lower housing 1 form a first packaging part. The electronic components 21 are packaged inside the first packaging part. The cover 3 has an escape opening a. At least the wiring part 22a of the wiring terminal 22 passes through the escape opening a and is exposed on the cover 3.

[0042] The wiring cover 4 is connected to the outer wall of the cover body 3, and the wiring cover 4 and the cover body 3 form a second packaging part. The wiring terminal 22 is packaged inside the second packaging part. The second packaging part is provided with a wire passing port b, which is configured to connect the wiring harness 01 through the connecting terminal 22.

[0043] The utility model frequency converter improves the shell structure of the traditional frequency converter, and sets the upper shell as a split structure of the cover body 3 and the wiring cover 4. When assembling, the cover body 3 is first connected to the lower shell 1, and the electronic components 21 are encapsulated inside the first encapsulation part formed by the lower shell 1 and the cover body 3, so as to ensure that the protection of the electronic components 21 is reliable and meets the required level requirements, such as meeting the IP20 level requirements; and at least the wiring part 22a of the wiring terminal 22 passes through the avoidance opening a and is exposed to the cover body 3. At this time, the wiring operation can be carried out, such as Figure 5 As shown, the wiring portion 22a of the terminal block 22 is exposed on the cover 3, and the wiring personnel can observe the position of the wiring portion 22a without any obstacles, and the cover 3 will not interfere with the wiring operation. The wiring personnel do not need to make blind connections, the visibility is strong, the operating space is not limited, the operability is strong, the wiring is convenient and fast, and the wiring accuracy and efficiency of the wiring personnel are improved.

[0044] After the wiring operation is completed, the wiring cover 4 is connected to the cover body 3, and the wiring terminals 22 are encapsulated inside the second encapsulation part formed by the wiring cover 4 and the cover body 3, ensuring that the protection of the electronic components 21 is reliable and meets the required level requirements, such as meeting the IP20 level requirements. At the same time, the second encapsulation part is also provided with a wire passing port b to avoid the connection harness 01, ensuring that the wiring cover 4 and the connection harness 01 do not interfere with each other, and ensuring that the wiring cover 4 is installed reliably.

[0045] Please refer to Figure 3 , Figure 5 and Figure 6 , Figure 6 for Figure 1 Schematic diagram of the structure of the inverter from the second angle.

[0046] like Figure 3As shown, in this embodiment, the inverter has a first wiring area S1 and a second wiring area S2, the wiring terminals 22 located in the first wiring area S1 are distributed in sequence to form a row, and the wiring terminals 22 located in the second wiring area S2 are distributed in sequence to form a row, the number of wiring covers 4 is two, and the wiring terminals 22 in the same wiring area are located inside the second packaging part formed by the same wiring cover 4 and the cover body 3.

[0047] In practice, the wiring cover 4 is not limited to the above arrangement, for example, each wiring terminal 22 is enclosed by a wiring cover 4; or, in the second wiring area S2, the two wiring terminals 22 at the left end are enclosed by one wiring cover 4, and the three wiring terminals 22 at the right end are enclosed by another wiring cover 4. In other words, each wiring cover 4 can enclose at least one wiring terminal 22.

[0048] Of course, in this embodiment, each wiring terminal 22 in the same wiring area is encapsulated by a wiring cover 4. The wiring cover 4 is a long strip structure with higher structural strength. Each wiring area only requires one installation action, and the installation is convenient and fast.

[0049] Since the structures of the wiring cover 4 and the connection method between the wiring cover 4 and the cover body 3 in the first wiring area S1 and the second wiring area S2 are the same, the second wiring area S2 is taken as an example below.

[0050] like Figure 2 As shown, in this embodiment, the connection portion 22a of the connection terminal 22 faces the upper end, and when connecting, the connecting harness 01 is fixed to the upper side wall of the connection portion 22a.

[0051] Based on the structure of the above-mentioned terminal block 22, as Figure 3 As shown, in this embodiment, the number of avoidance openings a provided on the cover body 3 is consistent with the number of wiring terminals 22, and the wiring terminals 22 pass through the avoidance openings a one-to-one; at the same time, the outer wall of the cover body 3 has a barrier portion 31 arranged along the circumference of the corresponding avoidance opening a, and the barrier portion 31 is provided with a first notch portion 31a, and the first notch portion 31a passes through the upper end wall of the barrier portion 31, and the barrier portion 31 forms a partial structure of the second packaging portion, and the first notch portion 31a participates in the formation of the wire passing opening b.

[0052] As set above, in this embodiment, a barrier portion 31 is set in the circumferential direction of each avoidance opening a, and the barrier portion 31 participates in forming the second packaging portion, thereby playing a protective role for the corresponding terminal 22; when wiring, the connecting harness 01 passes through the first notch portion 31a from top to bottom until the wiring end of the connecting harness 01 fits with the wiring portion 22a of the terminal 22 and is fixed together by bolts.

[0053] It can be seen that, since the wiring portion 22a of the wiring terminal 22 faces the upper end, the barrier portion 31 provided in the circumferential direction of the avoidance opening a will not interfere with the wiring operation, thus ensuring the convenience of the wiring operation.

[0054] Please continue to refer to Figure 3 and Figure 5 In this embodiment, the cover body 3 specifically includes a cover body 3A and a flat portion 3B. The electronic components 21 are encapsulated in the space where the cover body 3A is located. The flat portion 3B is connected to the cover body 3A. The side wall of the cover body 3A connecting the platform portion 3B is defined as the first side wall A. The avoidance opening a is set on the flat portion 3B. The flat portion 3B is provided with a barrier member 3C in the circumferential direction corresponding to the avoidance opening a. The inner end of the barrier member 3C is connected to the first side wall A. The circumferential wall of the barrier member 3C facing the outer end is provided with the aforementioned first notch portion 31a. The first side wall A and the barrier member 3C together form the aforementioned barrier portion 31.

[0055] Please refer to Figure 1 , Figure 4 and Figure 7 , Figure 7 for Figure 1 Schematic diagram of the structure of the wiring cover in the inverter.

[0056] In this embodiment, the wiring cover 4 includes an upper cover portion 41, which is connected to the top of the partition portion 31, and the lower side wall of the upper cover portion 41 is in contact with or has a spacing with the upper side wall of the corresponding partition portion 31, and the upper cover portion 41 forms a partial structure of the second packaging portion.

[0057] As set above, the upper cover portion 41 actually forms the top wall of the second packaging portion, and the upper cover portion 41 and the barrier portion 31 jointly form the second packaging portion to ensure reliable protection of the electronic components 21. In practice, the distance between the lower side wall of the upper cover portion 41 and the upper side wall of the barrier portion 31 can be adaptively set according to the creepage distance requirements.

[0058] In this embodiment, the barrier portion 31 is disposed on the cover body 3 . In practice, it is also feasible to dispose the barrier portion 31 on the wiring cover 4 .

[0059] Furthermore, in this embodiment, the wiring cover 4 also includes a folding portion 42, which is connected to the upper cover portion 41 and extends downward. The folding portion 42 is provided with a second notch portion 42a, and the second notch portion 42a is connected to the corresponding first notch portion 31a. The second notch portion 42a participates in forming the avoidance opening a.

[0060] As set above, the wiring cover 4 is a right-angle structure formed by the upper cover part 41 and the folding part 42. Compared with the flat plate structure in which the wiring cover 4 only includes the upper cover part 41, the structural strength is higher, ensuring the structural stability of the wiring cover 4. At the same time, the folding part 42 can also play a shielding role to prevent the various barrier parts 31 from being exposed, making the wiring area more neat and the user experience better. In practice, the lower end of the folding part 42 can extend to contact the wall surface of the flat part 3B. At this time, the folding part 42 can also play a supporting role to ensure the reliable installation of the wiring cover 4.

[0061] Please refer to Figure 8 , Figure 8 for Figure 1 Schematic diagram of the structure of the inverter from the second angle.

[0062] In this embodiment, the wiring cover 4 further includes a reinforcing plate 43 . The reinforcing plate 43 is connected between the upper cover portion 41 and the folded portion 42 to further improve the structural strength of the wiring cover 4 .

[0063] It can be seen that the wiring cover 4 of this embodiment is provided with a plurality of reinforcing plates 43, and the plurality of reinforcing plates 43 are spaced apart along the length direction of the wiring cover 4. In practice, the number of reinforcing plates 43 is not limited, and the number of reinforcing plates 43 may be at least one.

[0064] Please continue to refer to Figure 3-Figure 5 In this embodiment, the cover body 3 is provided with a support portion 32. When the upper cover portion 41 is connected to the cover body 3, the lower side wall of the upper cover portion 41 is supported on the upper side wall of the support portion 32. In this way, the support portion 32 plays a supporting role for the wiring cover 4, thereby improving the installation reliability of the wiring cover 4.

[0065] Depend on Figure 3 It can be seen that in this embodiment, the support portion 32 is higher than the barrier portion 31. Therefore, when the wiring cover 4 is installed on the cover body 3, there is a gap between the lower side wall of the upper cover portion 41 and the upper side wall of the corresponding barrier portion 31. In practice, there is no restriction on the relative position of the support portion 32 and the barrier portion 31. For example, the support portion 32 and the barrier portion 31 can also be flush, the lower side wall of the upper cover portion 41 is in contact with the upper side wall of the corresponding barrier portion 31, and the support portion 32 and the barrier portion 31 simultaneously play a supporting role for the wiring cover 4. Of course, it is also feasible not to set the support portion 32 at this time, and the barrier portion 31 plays a supporting role for the wiring cover 4.

[0066] In this embodiment, the second wiring area S2 is provided with two support portions 32. In practice, the number of the support portions 32 is not limited, for example, the number of the support portion 32 may be at least one.

[0067] Furthermore, in this embodiment, the wiring cover 4 and the cover body 3 are fixed by snapping. Figure 1 , Figure 3 and Figure 7It is understood that the two ends of the wiring cover 4 are connected with buckles 4a, the outer wall of the cover body 3 has two extension parts 33 extending upward, the extension parts 33 are located at the two ends of the same wiring area, the extension parts 33 are provided with snap holes 3a, and the snap parts 4a1 of the buckles 4a at the same end are snapped into the corresponding snap holes 3a.

[0068] As above, the wiring cover 4 and the cover body 3 are fixed by snap connection, that is, a detachable connection mode is adopted, the connection is reliable, and it is convenient to disassemble and assemble. In practice, the buckle 4a is set on the cover body 3, and the snap hole 3a is set on the wiring cover 4, which is also feasible.

[0069] In addition, in this embodiment, the buckles 4a are arranged at both ends in the length direction of the wiring cover 4. In practice, there is no restriction on the arrangement position of the buckles 4a. For example, if the support portion 32 has a hole portion, the lower side wall of the upper cover portion 41 may be provided with a corresponding protrusion portion. In the installed state, the protrusion portion is fixedly inserted into the corresponding hole portion to realize the clamping and fixing of the wiring cover 4. The hole portion forms a clamping hole, and the protrusion forms a buckle.

[0070] In addition, in practice, the connection cover 4 and the cover body 3 are not limited to the snap-fit ​​fixing method. For example, the connection cover 4 and the cover body 3 can also be fixed by a connecting piece.

[0071] Please continue to refer to Figure 7 In this embodiment, the buckle 4a includes a connecting portion 4a2 extending downward, the clamping portion 4a1 is located at the lower end of the connecting portion 4a2 and extends toward the direction close to the extending portion 33, and there is a distance between the connecting portion 4a2 and the extending portion 33, such as Figure 6 As shown, a gap h is formed between the upper cover portion 41 and the extending portion 33 .

[0072] As configured above, when the wiring cover 4 needs to be disassembled, the disassembly component can extend from the notch h into between the connecting portion 4a2 and the extending portion 33 to pry the clamping portion 4a1 out from the inside of the clamping hole 3a, thereby improving the disassembly efficiency of the wiring cover 4.

[0073] The above are only preferred implementations of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A frequency converter, characterized in that: include: A main body, the main body comprising a lower shell (1) and a control circuit board (2), the control circuit board (2) being mounted on the lower shell (1), the control circuit board (2) being integrated with electronic components (21) and connection terminals (22), the connection terminals (22) having a connection portion (22a); An upper shell, the upper shell comprising a cover body (3) and a wiring cover (4), the cover body (3) being connected to the lower shell (1), the cover body (3) and the lower shell (1) forming a first packaging portion, the electronic component (21) being packaged inside the first packaging portion, the cover body (3) having a avoidance opening (a), at least the wiring portion (22a) of the wiring terminal (22) passing through the avoidance opening (a) and exposed outside the cover body (3), The wiring cover (4) is connected to the cover body (3), the wiring cover (4) and the cover body (3) form a second packaging part, the wiring terminal (22) is packaged inside the second packaging part, and the second packaging part is provided with a wire passing opening (b), and the wire passing opening (b) is configured to be used for the connection harness (01) to pass through.

2. The frequency converter according to claim 1, characterized in that: The connection terminals (22) pass through the inside of the avoidance opening (a) in a one-to-one correspondence, and the connection portion (22a) faces the upper end. The outer wall of the cover body (3) has a baffle portion (31) arranged along the circumferential direction corresponding to the avoidance opening (a), the baffle portion (31) is provided with a first notch portion (31a), the first notch portion (31a) penetrates the upper end wall of the baffle portion (31), the baffle portion (31) forms a partial structure of the second packaging portion, and the first notch portion (31a) participates in forming the wire passing opening (b).

3. The frequency converter according to claim 2, characterized in that: The wiring cover (4) comprises an upper cover portion (41), the upper cover portion (41) being connected above the baffle portion (31), the lower side wall of the upper cover portion (41) being in contact with or spaced apart from the upper side wall of the corresponding baffle portion (31), and the upper cover portion (41) forming a partial structure of the second packaging portion.

4. The frequency converter according to claim 3, characterized in that: The wiring cover (4) further comprises a folding portion (42), the folding portion (42) being connected to the upper cover portion (41) and extending downwards, the folding portion (42) being provided with a second notch portion (42a), the second notch portion (42a) being connected to the corresponding first notch portion (31a), and the second notch portion (42a) participating in forming the avoidance opening (a).

5. The frequency converter according to claim 4, characterized in that: The wiring cover (4) further comprises a reinforcing plate (43), wherein the reinforcing plate (43) is connected between the upper cover portion (41) and the folding portion (42).

6. The frequency converter according to claim 3, characterized in that: The cover body (3) is provided with a support portion (32), and when the upper cover portion (41) is connected to the cover body (3), the lower side wall of the upper cover portion (41) is supported on the upper side wall of the support portion (32).

7. The frequency converter according to any one of claims 1 to 6, characterized in that: The frequency converter has at least one wiring area, and the wiring terminals (22) located in the same wiring area are arranged in sequence to form a row, and the wiring terminals (22) in the same wiring area are located inside the second packaging portion formed by the same wiring cover (4) and the cover body (3).

8. The frequency converter according to any one of claims 1 to 6, characterized in that: One of the wiring cover (4) and the cover body (3) is provided with a buckle (4a), and the other is provided with a clamping hole (3a), and a clamping portion of the buckle (4a) is clamped into the corresponding clamping hole (3a).

9. The frequency converter according to claim 8, characterized in that: The frequency converter has at least one wiring area, the wiring terminals (22) located in the same wiring area are arranged in sequence to form a row, and the wiring terminals (22) in the same wiring area are located inside the second packaging portion formed by the same wiring cover (4) and the cover body (3); The two ends of the wiring cover (4) are connected to the buckles (4a), the outer wall of the cover body (3) has two extending portions (33) extending upwards, the extending portions (33) are located at the two ends of the same wiring area, the extending portions (33) are provided with the clamping holes (3a), and the clamping portions (4a1) of the buckles (4a) at the same end are clamped in the corresponding clamping holes (3a).

10. The frequency converter according to claim 9, characterized in that: The buckle (4a) comprises a connecting portion (4a2) extending downwards, the clamping portion (4a1) is located at the lower end of the connecting portion (4a2) and extends in a direction close to the extending portion (33), and there is a distance between the connecting portion (4a2) and the extending portion (33).

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