A sealed rotor lead assembly structure

Abstract

This invention belongs to the field of motor manufacturing technology and provides a closed-end rotor lead assembly structure, including a rotor, an insulating bushing, insulating lead screws, connecting screws, lead slot wedges, a closed end, and lead wires. The closed end is screwed into a closed end mounting slot. The lead slot wedge includes multiple slot wedge units. The rotor has lead mounting slots and receiving slots adapted to the lead wires. The insulating bushing is placed in the receiving slot, and the closed end abuts against the insulating bushing. The insulating bushing has an opening on its side wall and a connecting port at its bottom end, with the opening communicating with the connecting port. The connecting screw is placed inside the rotor. One end of the lead wire is connected to the connecting screw through the insulating lead screw, and the other end of the lead wire extends to the outside of the rotor by passing through the opening, the lead mounting slot, and the slot wedge mounting slot in sequence. This rotor lead assembly structure not only reduces the amount of rotor machining and enhances the rotor's rigidity, but the multi-segment lead slot wedge structure also facilitates future unit maintenance and inspection of faulty contact points.

Description

Technical Field

[0001] This invention belongs to the field of motor manufacturing technology, specifically relating to a closed-cover rotor lead assembly structure. Background Technology

[0002] In the lead wire and connection structure of the motor rotor, the lead screw lacks an effective anti-displacement structure. When the rotor rotates at high speed, the lead screw is prone to displacement, which affects the normal operation of the motor.

[0003] Secondly, traditional slot wedges are integral pieces. Due to their large volume, a large groove needs to be excavated, typically from the installation point all the way to the rotor end, and then the slot wedge is slid in from the end. This results in a large amount of rotor machining, and excessive excavation can easily affect rotor balance, reduce stiffness, and make assembly and maintenance more complicated, hindering the inspection of poor contact points during unit maintenance. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a sealed rotor lead assembly structure that can solve the aforementioned problems.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a sealed rotor lead assembly structure, comprising a rotor, an insulating bushing, an insulating lead screw, a connecting screw, a lead slot wedge, a sealed end, and a lead; The end cap has threads on its side wall, and the rotor has an end cap mounting groove on its side wall. The end cap has threads on the inner side wall of the end cap mounting groove, and the end cap is screwed into the end cap mounting groove. The lead wire slot wedge includes multiple slot wedge units. A slider is provided on the side wall of the slot wedge unit. A slot wedge mounting groove is opened on the side wall of the rotor. A sliding groove is opened on the inner side wall of the slot wedge mounting groove. The slot wedge mounting groove and the sliding groove are both connected to the end cap mounting groove. The slot wedge unit is slidably disposed in the slot wedge mounting groove. The slider is embedded in the sliding groove. Multiple slot wedge units abut against each other in sequence. One end of the slot wedge unit abuts against the end cap. The rotor is provided with a lead wire mounting groove that is adapted to the lead wire, and the lead wire mounting groove is connected to the slot wedge mounting groove; The rotor is provided with a receiving groove. The lead wire mounting groove, the slot wedge mounting groove, and the end cap mounting groove are all connected to the receiving groove. The insulating bushing is disposed in the receiving groove. The end cap abuts against the insulating bushing. The insulating bushing has an opening on its side wall and a connecting port at its bottom end. The opening is connected to the connecting port. The connecting screw is disposed inside the rotor, with one end of the connecting screw extending into the communication port. One end of the lead wire is connected to the connecting screw via the insulated lead wire screw, and the other end of the lead wire extends to the outside of the rotor by passing through the opening, the lead wire mounting groove, and the slot wedge mounting groove in sequence.

[0006] Preferably, a steel plate is held between the lead wire and the slot wedge unit.

[0007] Preferably, an insulating gasket is sandwiched between the steel plate and the lead wire.

[0008] Preferably, the slotted wedge unit is provided with positioning holes.

[0009] Preferably, the slotted wedge unit that abuts against the end cap has a curved surface structure adapted to the end cap, and the curved surface structure has threads.

[0010] Preferably, the thickness of the slotted wedge unit gradually increases in the direction away from the end cap.

[0011] Preferably, the slotted wedge unit at the end furthest from the end of the end is provided with a chamfered structure.

[0012] Preferably, the end cap is provided with two control holes.

[0013] Preferably, one end of the lead wire is provided with a connecting ring, the insulating lead wire screw is screwed to the connecting screw, the connecting ring is sleeved on the outside of the insulating lead wire screw, and the connecting ring is clamped between the end cap of the insulating lead wire screw and the connecting screw.

[0014] Preferably, a washer is held between the end cap of the insulated lead screw and the connecting ring.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention provides a closed-type rotor lead assembly structure, which replaces the insulated lead screw with a closed-type structure. The closed end can be installed and removed at any time, and also serves to fix the insulated lead screw, preventing it from shifting during high-speed rotor rotation. This ensures the stability of the structure during high-speed operation.

[0016] Meanwhile, the slot wedge was changed to a multi-segment design, allowing the slot wedge unit to enter and exit from the end-mounted slot and then slide into the slot wedge mounting slot, eliminating the need to excavate the slot wedge mounting slot to the rotor end, significantly reducing the amount of rotor machining. Moreover, the multi-segment slot wedge can be installed and removed segment by segment from the end-mounted slot, which not only reduces the amount of rotor machining and enhances the rotor's rigidity but also facilitates assembly and maintenance. Attached Figure Description

[0017] Figure 1This is a cross-sectional view of a sealed rotor lead assembly structure provided in an embodiment of the present invention. Figure 2 A cross-sectional view of the blind mounting groove and related parts of a blind-cover type rotor lead assembly structure provided in an embodiment of the present invention; Figure 3 A top view of a slot wedge unit and related parts of a closed-type rotor lead assembly structure provided in an embodiment of the present invention; Figure 4 One of the top view schematic diagrams of a slot wedge mounting groove and related parts of a closed-type rotor lead assembly structure provided in an embodiment of the present invention; Figure 5 A second top view of the slot wedge mounting groove and related parts of a closed-type rotor lead assembly structure provided in an embodiment of the present invention; Figure 6 One of the cross-sectional structural schematic diagrams of a slot wedge mounting groove and related parts of a covered rotor lead assembly structure provided in an embodiment of the present invention; Figure 7 A second cross-sectional view of a slot wedge mounting groove and related parts of a sealed rotor lead assembly structure provided in an embodiment of the present invention; Figure 8 A three-dimensional structural schematic diagram of an insulating bushing for a sealed rotor lead assembly structure provided in an embodiment of the present invention; Figure 9 A three-dimensional structural schematic diagram of a lead slot wedge of a sealed rotor lead assembly structure provided in an embodiment of the present invention; Figure 10 A top view of the blind-type rotor lead assembly structure provided in an embodiment of the present invention; Figure 11 This is a side view of the lead wire structure of a sealed rotor lead wire assembly structure provided in an embodiment of the present invention; Figure 12 This is a top view of a lead wire in a sealed rotor lead wire assembly structure provided in an embodiment of the present invention. Figure 13 This is a cross-sectional view of a washer and related parts of a sealed rotor lead assembly structure provided in an embodiment of the present invention.

[0018] The attached diagram lists the components represented by each number as follows: 1. Rotor; 2. Insulating bushing; 201. Upper insulating bushing; 202. Lower insulating bushing; 3. Insulated lead screw; 4. Connecting screws; 5. Lead wire slot wedge; 501. Slot wedge unit; 502. Slider; 503. Positioning hole; 504. Curved surface structure; 505. Chamfer structure; 6. Blind spot; 601. Control hole; 7. Lead wire; 8. Slotted wedge installation groove; 9. Slide groove; 10. Lead wire mounting slot; 11. Receiving tank; 12. Opening; 13. Connecting port; 14. Concealed mounting slot; 15. Steel plate; 16. Insulating gaskets; 17. Connecting ring; 18. Washers. Detailed Implementation

[0019] To make the technical solutions and advantages of the embodiments of this application clearer, the exemplary embodiments of this application will be described in further detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not an exhaustive list of all embodiments. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0020] This embodiment provides a sealed rotor lead assembly structure, including a rotor 1, an insulating bushing 2, an insulating lead screw 3, a connecting screw 4, a lead slot wedge 5, a sealed end 6, and a lead 7.

[0021] The side wall of the plug 6 is provided with threads, and the side wall of the rotor 1 is provided with a plug mounting groove 14. The inner side wall of the plug mounting groove 14 is provided with threads, and the plug 6 is screwed into the plug mounting groove 14. For example, see Figure 1-4 The end cap 6 has a columnar structure. The end cap mounting groove 14 is compatible with the end cap 6, so that the end cap 6 can be screwed into the end cap mounting groove 14 and the end cap 6 can be completely screwed into the end cap mounting groove 14 to prevent the top part from being exposed.

[0022] For example, see Figure 10 The top of the plug 6 can be provided with two control holes 601. During installation or disassembly, the plug 6 can be rotated by inserting the two control rods into the two control holes 601 respectively and then rotating the two control rods. The operation is simple and convenient.

[0023] The lead wire slot wedge 5 includes multiple slot wedge units 501. A slider 502 is provided on the side wall of the slot wedge unit 501. A slot wedge mounting groove 8 is provided on the side wall of the rotor 1. A sliding groove 9 is provided on the inner side wall of the slot wedge mounting groove 8. The slot wedge mounting groove 8 and the sliding groove 9 are both connected to the end cap mounting groove 14. The slot wedge unit 501 is slidably disposed in the slot wedge mounting groove 8. The slider 502 is embedded in the sliding groove 9. Multiple slot wedge units 501 abut against each other in sequence. One end of the slot wedge unit 501 abuts against the end cap 6. For example, see Figure 3 , Figure 9 The lead wire slot wedge 5 includes eleven slot wedge units 501. Each slot wedge unit 501 has a slider 502 on both its left and right side walls. The slot wedge unit 501 and the slider 502 can be an integral structure. The slot wedge unit 501 is relatively small and can be directly placed into the end-mounting slot 14. The actual number of slot wedge units 501 can be determined based on the actual size of the rotor 1 and usage requirements.

[0024] For example, see Figure 6 The rotor 1 has a wedge mounting groove 8 on its side wall, and sliding grooves 9 are formed on the left and right inner side walls of the wedge mounting groove 8. (See also...) Figure 2 , Figure 4 The right end of the slot wedge mounting groove 8 and the right end of the sliding groove 9 are both connected to the end plate mounting groove 14. At the same time, the length of the slot wedge mounting groove 8 is longer than that of the sliding groove 9, that is, the left end of the slot wedge mounting groove 8 extends to the left side of the left end of the sliding groove 9.

[0025] For example, see Figure 1 , Figure 2 , Figure 7 The slot wedge unit 501 can enter the slot wedge mounting groove 8 through the blind mounting groove 14, while the slider 502 is embedded in the sliding groove 9 on the same side, allowing the slot wedge unit 501 to slide along the slot wedge mounting groove 8. In this way, all eleven slot wedge units 501 can be placed into the slot wedge mounting groove 8 segment by segment until the slider 502 of the first inserted slot wedge unit 501 abuts against the inner wall of the left end of the sliding groove 9. At this point, all eleven slot wedge units 501 abut in sequence and cannot move further to the left. See also... Figure 3 , Figure 9 The last inserted slotted wedge unit 501 has a curved surface structure 504 on its right end that is adapted to the end cap 6, and the curved surface structure 504 is threaded. It should be noted that after all eleven slotted wedge units 501 are inserted into the slotted wedge mounting slot 8 and abut against each other, the end cap 6 is screwed into the end cap mounting slot 14. At this time, the curved surface structure 504 of the last inserted slotted wedge unit 501 can be screwed into the end cap 6, so that the slotted wedge unit 501 and the end cap 6 are in contact, thereby ensuring that all eleven slotted wedge units 501 remain stable and preventing the slotted wedge units 501 from sliding back and forth.

[0026] The rotor 1 is provided with a lead wire mounting groove 10 that is compatible with the lead wire 7. The lead wire mounting groove 10 is connected to the slot wedge mounting groove 8. The rotor 1 is provided with a receiving groove 11. The lead wire mounting groove 10, the slot wedge mounting groove 8, and the end cap mounting groove 14 are all connected to the receiving groove 11. The insulating bushing 2 is placed in the receiving groove 11. The end cap 6 abuts against the insulating bushing 2. The side wall of the insulating bushing 2 is provided with an opening 12. The bottom end of the insulating bushing 2 is provided with a connecting port 13. The opening 12 is connected to the connecting port 13. For example, see Figure 2 , Figure 6 The lead wire mounting groove 10 is located inside the slot wedge mounting groove 8. The left end of the lead wire mounting groove 10 can be flush with the slot wedge mounting groove 8, and the right end of the lead wire mounting groove 10 is connected to the receiving groove 11.

[0027] For example, see Figure 2 The receiving groove 11 is located inside the end cap mounting groove 14, and the left end of the receiving groove 11 extends to the left side of the left end of the end cap mounting groove 14. See also Figure 5 The insulating bushing 2 is adapted to the receiving groove 11, and the width of the receiving groove 11 is the same as the width of the slot wedge mounting groove 8, allowing the insulating bushing 2 to enter from the end mounting groove 14 and the slot wedge mounting groove 8 and be placed into the receiving groove 11. At this time, the insulating bushing 2 can only move upward and cannot move in all directions. See also Figure 1 After the plug 6 is screwed into the plug mounting groove 14, the bottom end of the plug 6 abuts against the top end of the insulating bushing 2, thereby making the insulating bushing 2 stable.

[0028] For example, see Figure 8 The insulating bushing 2 may include an upper insulating bushing 201 and a lower insulating bushing 202, with the upper insulating bushing 201 and the lower insulating bushing 202 being connected in a mating manner.

[0029] The connecting screw 4 is installed inside the rotor 1. One end of the connecting screw 4 extends into the communication port 13. One end of the lead wire 7 is connected to the connecting screw 4 through the insulated lead wire screw 3. The other end of the lead wire 7 passes through the opening 12, the lead wire mounting groove 10, and the slot wedge mounting groove 8 in sequence and extends to the outside of the rotor 1. For example, see Figure 2 The connecting screw 4 is fixedly disposed inside the rotor 1, with its tip extending into the receiving groove 11 and further into the connecting port 13. (See also...) Figure 1 The insulating lead screw 3 is screwed into the connecting screw 4, thus connecting the right end of the lead 7 to the connecting screw 4. At the same time, the top of the insulating lead screw 3 abuts against the upper insulating bushing 201. It can be understood that when the end cap 6 is screwed into the end cap mounting groove 14, it can press the upper insulating bushing 201, and then press the lower insulating bushing 202 and the insulating lead screw 3, preventing the insulating lead screw 3 from radially displacing during the high-speed rotation of the rotor 1, making the entire lead structure more compact, safe and reliable.

[0030] For example, see Figure 1 The left end of the lead wire 7 passes through the opening 12 into the lead wire mounting groove 10, and then extends to the left end of the lead wire mounting groove 10. It then extends upward through the slot wedge mounting groove 8 to the outside of the rotor 1. It should be noted that there is a gap between the leftmost slot wedge unit 501 and the inner wall of the left end of the slot wedge mounting groove 8.

[0031] In summary, the sealed rotor lead assembly structure provided in this embodiment is as follows: During installation, the lower insulating bushing 202 is placed in the receiving groove 11, and then the insulating lead screw 3 is screwed into the connecting screw 4, so that the right end of the lead 7 is connected to the connecting screw 4. Then, the upper insulating bushing 201 is placed on top, so that the left end of the lead 7 passes through the opening 12, the lead mounting groove 10, and the slot wedge mounting groove 8 in sequence to extend to the outside of the rotor 1. Then, it slides into the slot wedge unit 501 section by section through the end cap mounting groove 14, and finally tightens the end cap 6, so that the end cap 6 presses against the insulating bushing 2, which can prevent the insulating lead screw 3 from radially displacing during the high-speed rotation of the rotor 1.

[0032] When maintenance is required, simply unscrew the plug 6 and then remove the slotted wedge unit 501 piece by piece in sequence. The operation is simple and safe.

[0033] The design incorporates a closed-end structure above the insulating lead screw 3. This closed-end 6 allows for easy installation and removal, while also securing the insulating lead screw 3 and preventing displacement during the high-speed rotation of the rotor 1. This ensures a compact, safe, reliable, and easy-to-disassemble lead structure with high practicality.

[0034] Meanwhile, the lead wire slot wedge 5 is changed to a multi-segment design, allowing the slot wedge unit 501 to enter and exit from the blind mounting slot 14 and then slide into the slot wedge mounting slot 8. This eliminates the need to excavate the slot wedge mounting slot 8 to the end of the rotor 1, significantly reducing the machining workload of the rotor 1. Furthermore, the multi-segment slot wedge can be installed and removed segment by segment from the blind mounting slot 14, which not only reduces the machining workload of the rotor and enhances the rigidity of the rotor 1, but also facilitates assembly and maintenance.

[0035] Based on the above technical solution, in the technical solution provided in this embodiment, a steel plate 15 is clamped between the lead wire 7 and the slot wedge unit 501; An insulating pad 16 is sandwiched between the steel plate 15 and the lead wire 7; For example, see Figure 7 The steel plate 15 provides support, effectively ensuring the stability and uniformity of the lead wire 7 and preventing it from bending, deforming, or even arching. The insulating pad 16 enhances the insulation of the lead wire 7 and also protects it.

[0036] In the technical solution provided in this embodiment, the slotted wedge unit 501 is provided with a positioning hole 503; For example, see Figure 9 The top of the slot wedge unit 501 is provided with a positioning hole 503. By inserting the positioning rod into the positioning hole 503, the slot wedge unit 501 can be moved left and right quickly, which is simple and convenient to operate.

[0037] The thickness of the slot wedge element 501 gradually increases in the direction away from the head 6; For example, see Figure 9 From right to left, the thickness of the slot wedge unit 501 gradually increases, with the leftmost slot wedge unit 501 having the greatest thickness. Furthermore, the lower left corner of the leftmost slot wedge unit 501 has a chamfer structure 505, which serves as a guide to prevent the tip of the slot wedge unit 501 from contacting the lead wire 7. The gradual increase in thickness from right to left among the slot wedge units 501 ensures smooth force transmission in the lateral direction among the eleven slot wedge units 501. Additionally, the varying thickness of the slot wedge units 501 facilitates identification of units at different positions, aiding in their sequential placement. It should be noted that the thickness of the slider 502 remains unaffected.

[0038] In the technical solution provided in this embodiment, one end of the lead wire 7 is provided with a connecting ring 17, the insulating lead wire screw 3 is screwed to the connecting screw 4, the connecting ring 17 is sleeved on the outside of the insulating lead wire screw 3, and the connecting ring 17 is clamped between the end cap of the insulating lead wire screw 3 and the connecting screw 4. A washer 18 is clamped between the end cap of the insulating lead screw 3 and the connecting ring 17; For example, see Figure 11-12 A connecting ring 17 is provided at the right end of lead 7. See also Figure 13 The connecting screw 4 has a step with a screw hole at its top. The bottom end of the insulated lead screw 3 passes through the washer 18 and the connecting ring 17 in sequence and is screwed onto the step, thus pressing the washer 18 and the connecting ring 17 onto the connecting screw 4. The washer 18 can protect the connecting ring 17. The structure is simple and easy to operate.

[0039] The insulating lead screw 3 can be a bidirectional screw with a nut screwed to its top, which is the end cap mentioned above. By rotating the nut, the height of the nut can be finely adjusted so that the upper insulating bushing 201 abuts against the nut, thus fully clamping the insulating lead screw 3. At the same time, the nut can clamp the washer 18 and the connecting ring 17 below.

[0040] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application 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, and therefore should not be construed as a limitation of this application.

[0041] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0042] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0043] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A cover-plug type rotor lead assembly structure characterized by comprising: Includes rotor (1), insulating bushing (2), insulating lead screw (3), connecting screw (4), lead slot wedge (5), end cap (6), and lead wire (7); The end cap (6) has threads on its side wall, and the rotor (1) has an end cap mounting groove (14) on its side wall. The end cap mounting groove (14) has threads on its inner side wall, and the end cap (6) is screwed into the end cap mounting groove (14). The lead wire slot wedge (5) includes multiple slot wedge units (501). A slider (502) is provided on the side wall of the slot wedge unit (501). A slot wedge mounting groove (8) is provided on the side wall of the rotor (1). A sliding groove (9) is provided on the inner side wall of the slot wedge mounting groove (8). The slot wedge mounting groove (8) and the sliding groove (9) are both connected to the end cap mounting groove (14). The slot wedge unit (501) is slidably disposed in the slot wedge mounting groove (8). The slider (502) is embedded in the sliding groove (9). Multiple slot wedge units (501) abut against each other in sequence. One end of the slot wedge unit (501) abuts against the end cap (6). The rotor (1) is provided with a lead wire mounting groove (10) adapted to the lead wire (7), and the lead wire mounting groove (10) is connected to the slot wedge mounting groove (8); The rotor (1) is provided with a receiving groove (11). The lead wire mounting groove (10), the slot wedge mounting groove (8), and the end cap mounting groove (14) are all connected to the receiving groove (11). The insulating bushing (2) is disposed in the receiving groove (11). The end cap (6) abuts against the insulating bushing (2). The insulating bushing (2) has an opening (12) on its side wall and a connecting port (13) at its bottom end. The opening (12) is connected to the connecting port (13). The connecting screw (4) is disposed inside the rotor (1). One end of the connecting screw (4) extends into the communication port (13). One end of the lead wire (7) is connected to the connecting screw (4) through the insulating lead wire screw (3). The other end of the lead wire (7) passes through the opening (12), the lead wire mounting groove (10), and the slot wedge mounting groove (8) in sequence and extends to the outside of the rotor (1).

2. The sealed rotor lead assembly structure according to claim 1, characterized in that, The steel plate (15) is held between the lead wire (7) and the slot wedge unit (501).

3. The sealed rotor lead assembly structure according to claim 2, characterized in that, An insulating pad (16) is sandwiched between the steel plate (15) and the lead wire (7).

4. The sealed rotor lead assembly structure according to claim 1, characterized in that, The slotted wedge unit (501) is provided with a positioning hole (503).

5. The sealed rotor lead assembly structure according to claim 1, characterized in that, The slotted wedge unit (501) that abuts against the end cap (6) is provided with a curved surface structure (504) adapted to the end cap (6), and the curved surface structure (504) is provided with threads.

6. The sealed rotor lead assembly structure according to claim 1, characterized in that, The thickness of the slot wedge unit (501) gradually increases in the direction away from the head (6).

7. The sealed rotor lead assembly structure according to claim 6, characterized in that, The slot wedge unit (501) at the end away from the end of the end cap (6) is provided with a chamfer structure (505).

8. The sealed rotor lead assembly structure according to claim 1, characterized in that, The plug (6) is provided with two control holes (601).

9. The sealed rotor lead assembly structure according to claim 1, characterized in that, One end of the lead wire (7) is provided with a connecting ring (17), the insulating lead wire screw (3) is screwed to the connecting screw (4), the connecting ring (17) is sleeved on the outside of the insulating lead wire screw (3), and the connecting ring (17) is clamped between the end cap of the insulating lead wire screw (3) and the connecting screw (4).

10. The sealed rotor lead assembly structure according to claim 9, characterized in that, A washer (18) is held between the end cap of the insulating lead screw (3) and the connecting ring (17).

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