Metallized film capacitor for AC motor

Abstract

The invention discloses a metallized film capacitor for an alternating current motor, and relates to the technical field of metallized film capacitors, the metallized film capacitor comprises a capacitor aluminum shell, a capacitor end cover, a threading part and a wire harness, the threading part is used for fixedly connecting the wire harness through crimping, and the metallized film capacitor also comprises a protection mechanism used for reducing the oxidation degree of the threading part. The protection mechanism comprises a sealing cover with the top provided with a circular sleeving hole, the threading part is located in the inner side of the sealing cover, the sealing cover slidably sleeves a wire body of the wire harness through the circular sleeving hole, an attaching sealing part is arranged between the wire harness and the inner wall of the circular sleeving hole, and the sealing cover is detachably connected with the top end face of the capacitor end cover. Through the arrangement of the sealing cover, after the threading part and the wire harness are fixedly connected through crimping, only the sealing cover needs to slide down to cover the threading part, so that the threading part can be effectively sealed and protected, the oxidation influence of the external environment on the threading part is reduced, and the service life of the threading part is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of metallized film capacitors, and in particular to a metallized film capacitor for an AC motor. Background Art

[0002] In modern electronic equipment and power systems, metallized film capacitors are widely used in many fields due to their excellent performance, such as high energy density, low loss, and good self-healing properties. Among them, energy storage capacitors in power systems and backup power capacitors for communication base stations are typical application scenarios of metallized film capacitors.

[0003] In actual operation, the connection between the wiring harness and the end cap of the metallized film capacitor is the key link to ensure the normal operation of the capacitor. At present, the common connection method is crimping, which can provide a certain connection strength in the initial stage and meet the basic electrical connection requirements of the capacitor.

[0004] However, as time goes by, problems gradually emerge. When the capacitor is in working condition for a long time, the crimping part will inevitably be affected by various factors, among which oxidation is particularly prominent. The metal material of the crimping part will react chemically with the oxygen in the air and gradually form an oxide layer. The existence of the oxide layer will increase the contact resistance and hinder the smooth transmission of current, which will cause the connection part to heat up. Long-term heating will further accelerate the oxidation process, forming a vicious circle. Summary of the invention

[0005] In order to solve the above technical problems, a metallized film capacitor for an AC motor is provided, which solves the problems raised in the background technology.

[0006] To achieve the above purpose, the technical solution adopted by the present invention is: a metallized film capacitor for an AC motor, comprising an aluminum capacitor shell, a capacitor end cover arranged on the top of the aluminum capacitor shell, a threading portion fixedly connected to the capacitor end cover, and a wire harness threaded in the threading portion, wherein the threading portion fixedly connects the wire harness by crimping, and further comprising a protective mechanism for reducing the degree of oxidation of the threading portion;

[0007] The protection mechanism includes a closing cover with a circular sleeve hole on the top, the threading portion is located on the inner side of the closing cover, and the closing cover is slidably sleeved on the wire body of the wiring harness through the circular sleeve hole, a close sealing portion is provided between the wiring harness and the inner wall of the circular sleeve hole, and the closing cover is detachably connected to the top end surface of the capacitor end cover.

[0008] Preferably, the fitting closing portion is mainly composed of an airbag and a pressure regulating assembly, the airbag is sleeved on the wiring harness body and fixedly connected to the inner wall of the circular sleeve hole, and a shrinkage groove connected to the interior of the airbag is also provided in the inner wall of the top of the closing cover, and the pressure regulating assembly is located in the shrinkage groove.

[0009] Preferably, the pressure regulating assembly includes a piston sliding in the shrinkage groove, and an internal threaded tube is vertically fixed to the side of the piston facing away from the airbag. The internal thread of the internal threaded tube is connected to an external threaded rod, and one end of the external threaded rod is rotated to pass through the closing cover and fixed with a control block.

[0010] Preferably, a limiting ring is sleeved on the outer wall of the internal threaded tube, a sliding groove is opened on the inner wall of the limiting ring, a limiting strip fixedly connected to the outer wall of the internal threaded tube is slidably arranged in the sliding groove, and the limiting ring is fixedly connected to the inner wall of the shrinkage groove through a bracket.

[0011] Preferably, an annular mounting groove is formed at the bottom end of the closing cover, and a positioning screw sleeve fixedly connected to the top end of the capacitor end cover is threadedly connected in the annular mounting groove.

[0012] Compared with the prior art, the advantages of the present invention are:

[0013] (1) By setting the closing cover, after the threading part and the wire harness are fixedly connected by crimping, the closing cover only needs to be slid down to cover the threading part, so that the threading part can be effectively sealed and protected, the oxidation effect of the external environment on the threading part can be reduced, and the service life of the threading part can be increased.

[0014] (2) By setting the close-fitting sealing part, when it is necessary to slide the closing cover down and set the threading part on the sealing cover, the gas in the airbag cavity is sucked in advance by using the pressure regulating component to separate the inner wall of the airbag from the wire harness body, so as to prevent the airbag from excessively contacting the outer wall of the wire harness during the sliding process of the closing cover, thereby causing movement obstruction. After the threading part is set on the closing cover, the pressure regulating component is used to inject gas into the airbag cavity, so that the inner wall of the airbag is in close contact with the wire harness body, thereby closing the circular set hole and improving the sealing of the inner cavity of the closing cover.

[0015] (3) By setting the positioning screw sleeve, when the sliding closing cover contacts the threading part, the closing cover is then manually turned with the knob to screw the positioning screw sleeve into the annular mounting groove under the threaded structure. In this way, the tightening characteristics of the threaded structure and the positioning function of the annular mounting groove are utilized to achieve a tight and stable connection between the closing cover and the threading part, and to ensure the sealing and reliability of the closing cover during actual operation, thereby greatly reducing the possibility of problems such as oxidation of the threading part due to loose connection. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0017] Figure 2 It is a schematic diagram of the local structure of the present invention;

[0018] Figure 3 This is a schematic diagram of the internal structure of the capacitor end cover of the present invention;

[0019] Figure 4 For the present invention Figure 3 Schematic diagram of the structure at A in the middle;

[0020] Figure 5 For the present invention Figure 4 Schematic diagram of the structure at point B in the middle.

[0021] The numbers in the figure are:

[0022] 1. Capacitor aluminum shell; 2. Capacitor end cover; 3. Threading part; 4. Wire harness; 5. Closing cover; 6. Positioning screw sleeve; 7. Air bag; 8. Shrinkage groove; 9. Piston; 10. Internal threaded cylinder; 11. External threaded rod; 12. Control block; 13. Limiting ring; 14. Limiting strip. DETAILED DESCRIPTION

[0023] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art may think of other obvious variations.

[0024] Reference Figure 1-5 As shown, a metallized film capacitor for an AC motor comprises an aluminum capacitor shell 1, a capacitor end cover 2 disposed on the top of the aluminum capacitor shell 1, a threading portion 3 fixedly connected to the capacitor end cover 2, and a wire harness 4 threaded in the threading portion 3, wherein the threading portion 3 is used to fix the wire harness 4 by crimping, and further comprises a protective mechanism for reducing the degree of oxidation of the threading portion 3;

[0025] The protection mechanism comprises a closing cover 5 with a circular sleeve hole on the top, the threading portion 3 is located inside the closing cover 5, and the closing cover 5 is slidably sleeved on the wire body of the wire harness 4 through the circular sleeve hole;

[0026] By setting the closing cover 5, after the threading part 3 and the wiring harness 4 are fixedly connected by crimping, it is only necessary to slide the closing cover 5 down to cover the threading part 3, so that the threading part 3 can be effectively sealed and protected, the oxidation effect of the external environment on the threading part 3 can be reduced, and the service life of the threading part 3 can be increased.

[0027] Further, refer to Figure 3-5 As shown, it is worth noting that a close-fitting closing portion is provided between the wiring harness 4 and the inner wall of the circular set hole;

[0028] The close fitting part is mainly composed of an airbag 7 and a pressure regulating assembly. The airbag 7 is sleeved on the wire body of the wire harness 4 and fixedly connected to the inner wall of the circular sleeve hole. A shrinkage groove 8 connected to the inside of the airbag 7 is also provided in the inner wall of the top of the closing cover 5. The pressure regulating assembly is located in the shrinkage groove 8.

[0029] By setting the close-fitting sealing part, when the closing cover 5 needs to be lowered and its sealing cover is set to the threading part 3, the gas in the inner cavity of the airbag 7 is sucked in advance by the pressure regulating component, so that the airbag 7 shrinks due to the reduction of air pressure, and its inner diameter is expanded, so that the inner wall of the airbag 7 is separated from the wire body of the wire harness 4, so as to prevent the airbag 7 from excessively contacting the outer wall of the wire harness 4 during the process of sliding down with the closing cover 5, causing movement obstruction;

[0030] On the contrary, after the closing cover 5 is covered with the threading part 3, the pressure regulating component is used to inject air into the inner cavity of the airbag 7. The airbag 7 is expanded by the air, and its inner diameter is reduced, so that the inner wall of the airbag 7 is closely attached to the wire body of the wiring harness 4, thereby closing the circular set hole and improving the sealing of the inner cavity of the closing cover 5.

[0031] Further, refer to Figure 4 and Figure 5 As shown, it is worth noting that the pressure regulating assembly includes a piston 9 sliding in the contraction groove 8, and an internal threaded tube 10 is vertically fixed on the side of the piston 9 facing away from the airbag 7. The internal threaded tube 10 is internally threadedly connected to an external threaded rod 11, and one end of the external threaded rod 11 rotates to pass through the closing cover 5 and is fixed with a control block 12;

[0032] The knob control block 12 makes the external threaded rod 11 rotate inside the contraction groove 8, and the internal threaded tube 10 can slide along the rod of the external threaded rod 11 under the threaded structure, pulling the piston 9 to move deep inside the contraction groove 8, sucking the gas inside the airbag 7, so that the air pressure inside the airbag 7 is reduced;

[0033] On the contrary, the control block 12 is reversed to cause the piston 9 to slide in the opposite direction, so that the piston 9 can squeeze the suction gas into the airbag 7 to increase the air pressure inside the airbag 7.

[0034] Further, refer to Figure 4 and Figure 5 As shown, it is worth noting that a limiting ring 13 is sleeved on the outer wall of the internal threaded tube 10, a sliding groove is opened on the inner wall of the limiting ring 13, a limiting strip 14 fixedly connected to the outer wall of the internal threaded tube 10 is slidably arranged in the sliding groove, and the limiting ring 13 is fixedly connected to the inner wall of the shrinkage groove 8 through a bracket;

[0035] By setting the limiting ring 13 and the limiting bar 14, when the external threaded rod 11 rotates, the limiting ring 13 cooperates with the limiting bar 14 to effectively limit the trajectory of the internal threaded tube 10, so that the internal threaded tube 10 can only slide linearly along the rod body of the external threaded rod 11 to prevent the internal threaded tube 10 from rotating together with the external threaded rod 11.

[0036] Further, refer to Figure 3 As shown, it is worth noting that the closing cover 5 is detachably connected to the top surface of the capacitor end cover 2;

[0037] The bottom end of the closing cover 5 is provided with an annular mounting groove, and a positioning screw sleeve 6 fixedly connected to the top end of the capacitor end cover 2 is threadedly connected in the annular mounting groove;

[0038] By setting the positioning screw sleeve 6, when the sliding closing cover 5 contacts the threading part 3, the closing cover 5 is then manually turned with the knob to make the positioning screw sleeve 6 screwed into the annular mounting groove under the threaded structure. In this way, the tightening characteristics of the threaded structure and the positioning function of the annular mounting groove can be used to achieve a tight and stable connection between the closing cover 5 and the threading part 3, and to ensure the sealing and reliability of the closing cover 5 during actual operation, thereby greatly reducing the possibility of problems such as oxidation of the threading part 3 due to loose connection.

[0039] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions only describe the principles of the present invention. The present invention may be subject to various changes and improvements without departing from the spirit and scope of the present invention. These changes and improvements fall within the scope of the present invention. The scope of protection claimed by the present invention is defined by the attached claims and their equivalents.

Claims

1. A metallized film capacitor for an AC motor, comprising an aluminum capacitor shell (1), a capacitor end cover (2) disposed on the top of the aluminum capacitor shell (1), a threading portion (3) fixedly connected to the capacitor end cover (2), and a wire harness (4) threaded in the threading portion (3), wherein the threading portion (3) fixedly connects the wire harness (4) by crimping, and is characterized in that: It also includes a protection mechanism for reducing the degree of oxidation of the threading portion (3); The protection mechanism comprises a closing cover (5) with a circular sleeve hole at the top, the threading portion (3) is located on the inner side of the closing cover (5), and the closing cover (5) is slidably sleeved on the wire body of the wire harness (4) through the circular sleeve hole, a close sealing portion is provided between the wire harness (4) and the inner wall of the circular sleeve hole, and the closing cover (5) is detachably connected to the top end surface of the capacitor end cover (2).

2. The metallized film capacitor for an AC motor according to claim 1, characterized in that: The close-fitting closing part is mainly composed of an airbag (7) and a pressure regulating assembly. The airbag (7) is sleeved on the wire body of the wire harness (4) and fixedly connected to the inner wall of the circular sleeve hole. The inner wall of the top of the closing cover (5) is also provided with a shrinkage groove (8) connected to the inside of the airbag (7). The pressure regulating assembly is located in the shrinkage groove (8).

3. The metallized film capacitor for an AC motor according to claim 2, characterized in that: The pressure regulating assembly comprises a piston (9) sliding in the contraction groove (8); an internal threaded tube (10) is vertically fixed to a side of the piston (9) facing away from the airbag (7); an external threaded rod (11) is internally threadedly connected to the internal threaded tube (10); one end of the external threaded rod (11) is rotated to pass through the closing cover (5) and is fixed with a control block (12).

4. The metallized film capacitor for an AC motor according to claim 3, characterized in that: The outer wall of the internally threaded tube (10) is sleeved with a limiting ring (13), the inner wall of the limiting ring (13) is provided with a sliding groove, a limiting strip (14) is slidably arranged in the sliding groove and is fixedly connected to the outer wall of the internally threaded tube (10), and the limiting ring (13) is fixedly connected to the inner wall of the shrinkage groove (8) through a bracket.

5. The metallized film capacitor for AC motor according to claim 1, characterized in that: An annular mounting groove is formed at the bottom end of the closing cover (5), and a positioning screw sleeve (6) is threadedly connected to the top end of the capacitor end cover (2).

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