Direct-acting three-position switch
By using the combination of insulating sleeve structure and fastening screw slots in the direct-acting three-station switch, the problem of poor coaxiality of the static contact is solved, the sliding smoothness of the movable contact and the stability of the overall structure are improved, and the installation space is saved.
Patent Information
- Application Number
- CN202421370256.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-17
- Publication Date
- 2025-04-25
- Estimated Expiration
- 2034-06-17
AI Technical Summary
During the installation process, the existing direct-acting three-station switches are prone to poor coaxiality of grounding static contacts, intermediate static contacts, and static contacts, resulting in poor sliding of the moving contacts, large wear and severe heat generation, and at the same time, the installation takes up a lot of space.
The insulated sleeve structure is adopted to fix the grounded static contact, intermediate static contact, and on-static contact in the insulated sleeve, tightening is achieved through external threads and annular hoops, and tightening screws are used to combine with the movable contact slot to ensure smooth positioning and movement of the movable contacts.
It effectively ensures the coaxiality of the static contacts, improves the sliding smoothness of the movable contacts, reduces wear and heat generation, and saves installation space, improves the stability and heat dissipation effect of the overall structure.
Smart Images
Figure CN222801680U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of electrical equipment, in particular to a direct-acting three-position switch. Background Art
[0002] The switchgear in the power system needs to be equipped with isolating switches and grounding switches. Closing the isolating switch is for the next step of power transmission operation, and closing the grounding switch is for the next step of safety maintenance operation. Therefore, the isolating switch and the grounding switch must form the following interlocking relationship: the grounding switch cannot be closed when the isolating switch is closed, and the isolating switch cannot be closed when the grounding switch is closed. The isolating switches and grounding switches of traditional switchgear are set separately. In order to achieve the above interlocking relationship, electrical interlocking is generally required for control, but the electrical interlocking has the problem of low reliability.
[0003] Later, people designed a direct-acting three-position switch. The direct-acting three-position switch has three fixed static contacts and one moving contact 30. The three static contacts are the grounding static contact 31, the middle static contact 32, and the connection static contact 33 (also called the conductive static contact). Figure 1 , Figure 2 As shown, the main bodies of the three stationary contacts are arranged on the same straight line and are all cylindrical structures. The moving contact 30 is in the shape of a round rod. The moving contact 30 is driven by the screw mechanism 21 to move linearly inside the cylindrical cavity of the three stationary contacts to switch the switch state. When the moving contact 30 is between the grounding stationary contact 31 and the middle stationary contact 32, the grounding stationary contact 31 and the middle stationary contact 32 are connected, which is equivalent to the grounding switch being closed and the isolating switch being opened. Figure 2 When the moving contact 30 is between the middle static contact 32 and the static contact 33, it is equivalent to the disconnector closing and the grounding switch opening. Figure 1 When the moving contact 30 is located in the center of its moving track, the moving contact 30 only contacts the middle static contact 32 but not the grounding static contact 31 or the connected static contact 33, which is equivalent to the disconnector and the grounding switch being in the open state. It can be seen that the direct-acting three-position switch actually integrates the functions of the disconnector and the grounding switch, and the position of the moving contact is unique at a specific moment, so it is absolutely impossible for the grounding switch and the disconnector to be closed at the same time.
[0004] Figure 3As shown, the direct-acting three-position switch is installed in the gas box 4 above the circuit breaker chamber 8, and a camera probe for observing the position of the moving contact 30 is also provided in the gas box. The grounding static contact 31, the middle static contact 32, and the connection static contact 33 need to be connected to the copper busbar respectively, wherein the connection static contact 33 needs to be connected to the branch busbar 36, the middle static contact 32 needs to be connected to the circuit breaker busbar 35 in the circuit breaker chamber, and the grounding static contact 31 needs to be connected to the grounding busbar. Since the moving contact 30 needs to pass through the front and rear faces of the intermediate static contact 32, the circuit breaker busbar 35 cannot be directly connected to the front and rear faces of the moving contact 30, that is, the intermediate static contact 32 also needs to be formed with an intermediate contact boss 321 protruding downward, and a through-wall conductive column 37 is connected below the intermediate contact boss 321. The lower end of the through-wall conductive column 37 is connected to the circuit breaker busbar 35 in the circuit breaker chamber, and the through-wall conductive column 37 is wrapped with a through-wall bushing seat 38. The installation method of the existing direct-acting three-position switch is as follows Figure 3 As shown: the grounding static contact 31 is attached to the front wall 41 of the gas box by using the first insulating bracket 81, the middle static contact 32 is supported above the bottom wall 43 of the gas box by using the wall bushing seat 38, and the closing static contact 33 is attached to the rear wall 42 of the gas box by using the second insulating bracket 82. The above installation method has the following problems:
[0005] 1. The grounding static contact 31, the connection static contact 33, and the middle static contact 32 are independently installed and positioned, so it is not easy to control the coaxiality. Poor coaxiality is not conducive to the smooth sliding of the moving contact 30 along the longitudinal straight line, resulting in large wear and serious heat generation of the moving contact;
[0006] Second, due to the longitudinal distance between the air box front wall 41 and the air box rear wall 42 ( Figure 3 EF distance) is longer than the overall longitudinal length of the three-position switch ( Figure 3 The GH distance is much larger, so the longitudinal dimension of the second insulating bracket 82 is larger, which further means that the second insulating bracket 82 will occupy more valuable space in the air box 4, making the arrangement of other electrical components inside the air box appear crowded;
[0007] 3. Since the front end of the connecting static contact 33 needs to be passed by the moving contact 30, and the rear side of the connecting static contact 33 needs to be connected to the second insulating bracket 82, the connecting static contact 33 can only be connected to the branch bus 36 through the side, that is, the connecting static contact 33 needs to be integrally formed with a protruding conductive plate 330 on the side. Utility Model Content
[0008] The utility model aims to overcome the above-mentioned disadvantages and provide a direct-acting three-position switch, which can easily ensure the coaxiality of the grounding static contact, the middle static contact and the connection static contact.
[0009] The purpose can be achieved according to the following scheme: a direct-acting three-position switch, comprising three fixed static contacts and one moving contact, the three static contacts are, from front to back, a grounding static contact, an intermediate static contact, and a connection static contact, the grounding static contact comprises a grounding contact body and a grounding contact boss protruding upward, the intermediate static contact comprises an intermediate contact body and an intermediate contact boss protruding downward, the cross sections of the grounding contact boss and the intermediate contact boss are both circular; the connection static contact, the intermediate contact body, and the grounding contact body are cylindrical, the moving contact is a round rod, and the moving contact is driven by a screw mechanism to move between the inner cavities of the grounding contact body, the intermediate contact body, and the connection static contact;
[0010] The invention is characterized in that an insulating sleeve is also provided, and the insulating sleeve is composed of two semicircular sleeve assemblies which are symmetrical on both sides; the said static contact, the middle contact body and the grounding contact body are tightly sleeved in the insulating sleeve; the rear end of the insulating sleeve is formed with an external thread, and a circular hoop is screwed with the external thread; the front end of each sleeve assembly is also integrally formed with an end panel, the front surface of the end panel is perpendicular to the central axis of the insulating sleeve, and the end panel is provided with a lock hole;
[0011] Each semicircular sleeve assembly is respectively provided with a first square notch, a second square notch, a first semicircular notch, and a second semicircular notch; when the two semicircular sleeve assemblies are assembled, the two first square notches are assembled to form a first observation window, the two second square notches are assembled to form a second observation window, the two first semicircular notches are assembled to form a first circular hollow hole, and the two second semicircular notches are assembled to form a second circular hollow hole, the diameter of the first circular hollow hole is the same as the diameter of the middle contact boss, the diameter of the second circular hollow hole is the same as the diameter of the grounding contact boss, the middle contact boss passes through the first circular hollow hole and is exposed outside the insulating sleeve, and the grounding contact boss passes through the second circular hollow hole and is exposed outside the insulating sleeve; the rear end face of the connecting static contact is exposed at the rear end of the insulating sleeve; the longitudinal position of the first observation window is located between the connecting static contact and the middle static contact, and the longitudinal position of the second observation window is located between the middle static contact and the grounding static contact.
[0012] The outer surface of the moving contact is provided with a slot extending in the longitudinal direction; the middle stationary contact is provided with screw holes arranged symmetrically on the left and right, and each sleeve assembly is provided with a mounting hole at a position corresponding to the screw hole; a fastening screw is also provided, and the fastening screw includes a nut, a threaded section, and a smooth section which are connected as one body in sequence, the surface of the threaded section is provided with threads, the surface of the smooth section is not provided with threads, and the diameter of the smooth section is smaller than the diameter of the threaded section; the fastening screw passes through the mounting hole of the insulating sleeve, the nut of the fastening screw is pressed on the insulating sleeve, the threaded section of the fastening screw is screwed into the screw hole of the middle stationary contact, and the smooth section of the fastening screw is embedded in the slot on the outer surface of the moving contact.
[0013] The outer surface of the insulating sleeve is formed with corrugated heat dissipation ribs.
[0014] An annular convex rib for limiting the longitudinal position of the stationary contact is formed on the inner surface of the insulating sleeve.
[0015] The insulating sleeve is made of epoxy resin material.
[0016] The utility model has the following advantages and effects:
[0017] 1. The grounding static contact, the middle static contact and the connection static contact are fixed and constrained in the insulating sleeve to form a whole, and then the whole is installed on the air box. Therefore, it is easy to ensure the coaxiality of the grounding static contact, the middle static contact and the connection static contact, and then make the coaxiality of the three high, which is conducive to the smooth movement of the moving contact.
[0018] 2. The connecting static contact does not need to be attached to the rear wall of the gas box by an insulating bracket, so the insulating bracket used to install the connecting static contact can be omitted, avoiding the insulating bracket from occupying valuable space in the cabinet; in addition, the branch bus can be directly connected to the rear end face of the connecting static contact, so the connecting static contact does not need to be integrally formed with a conductive plate protruding upward, and the connecting static contact can be made into a standard cylindrical shape, making its structure simpler.
[0019] 3. The circular hoop tightens the rear end of the insulating sleeve, so that the rear sections of the left and right sleeve assemblies are spliced and tightened; the front end of the insulating sleeve can be locked with the front wall of the air box by means of bolts passing through the lock holes of the end panel, so that the front end positions of the left and right insulating sleeves are stable, thereby achieving a stable splicing of the front ends of the insulating sleeves; and the middle sections of the two sleeve assemblies can be locked with the middle static contacts respectively with fastening screws, so that the middle sections of the left and right sleeve assemblies are indirectly spliced and tightened through the middle static contacts, thus achieving the left and right splicing and tightening of the entire insulating sleeve as a whole.
[0020] Fourth, the smooth section of the fastening screw can also be embedded in the groove on the outer surface of the moving contact, which can avoid unnecessary rotation of the moving contact during the rotation of the screw mechanism, that is, the fastening screw can play a role in circumferential positioning of the moving contact. Therefore, the fastening screw plays a dual purpose effect.
[0021] 5. The insulating sleeve is provided with a first observation window and a second observation window, which are convenient for visually observing the position of the moving contact. At the same time, the first observation window and the second observation window are also beneficial to the heat dissipation of the moving contact and the static contact, avoiding the high temperature of the moving contact and the static contact due to the existence of the insulating sleeve. Similarly, the outer surface of the insulating sleeve is formed with corrugated heat dissipation ribs, which is also beneficial to the heat dissipation of the three-position switch. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 It is a three-dimensional structural diagram of a direct-acting three-position switch.
[0023] Figure 2 It is a cross-sectional schematic diagram when the moving contact of the direct-acting three-position switch is in the grounding position.
[0024] Figure 3 This is a schematic diagram of the installation method of a traditional direct-acting three-position switch.
[0025] Figure 4 It is a three-dimensional structural schematic diagram of a specific embodiment of the utility model.
[0026] Figure 5 yes Figure 4 Schematic top view of the structure shown.
[0027] Figure 6 yes Figure 4 Schematic diagram of the structure shown.
[0028] Figure 7 yes Figure 5 Schematic diagram of the AA section structure.
[0029] Figure 8 yes Figure 6 Schematic diagram of the CC cross-section structure.
[0030] Fig. 9 yes Figure 8 Middle B is a partial enlarged schematic diagram.
[0031] Fig.10 It is a schematic diagram of the three-dimensional structure of the fastening screw.
[0032] Fig.11 It is a schematic diagram of the structure of an insulating sleeve.
[0033] Fig.12 yes Figure 4 Schematic diagram of the three-dimensional exploded view of the structure shown.
[0034] Fig.13 It is a schematic diagram of the exploded assembly relationship of the grounding static contact, the middle static contact, the connecting static contact and the screw rod.
[0035] Fig.14 It is a schematic diagram of the installation method of a specific embodiment of the utility model. DETAILED DESCRIPTION
[0036] Figure 4 , Figure 7 , Fig.12 , Fig.13As shown, a direct-acting three-position switch of this embodiment includes three fixed static contacts and one moving contact 30, and the three static contacts are, from front to back, a grounding static contact 31, an intermediate static contact 32, and a connection static contact 33. The grounding static contact 31 includes a grounding contact body 310 and a grounding contact boss 311 protruding upward, and the intermediate static contact 32 includes an intermediate contact body 320 and an intermediate contact boss 321 protruding downward, and the cross-sections of the grounding contact boss 311 and the intermediate contact boss 321 are both circular; the connection static contact 33, the intermediate contact body 320, and the grounding contact body 310 are cylindrical, and the moving contact 30 is a round rod. The moving contact 30 is driven by the screw mechanism 21 to move between the inner cavities of the grounding contact body 310, the intermediate contact body 320, and the connection static contact 33.
[0037] Figure 4 , Figure 5 , Figure 6 , Figure 7 , Fig.12 , Figure 8 As shown, an insulating sleeve 1 made of high-strength epoxy resin material is also provided. The insulating sleeve 1 is composed of two left-right symmetrical semicircular sleeve assemblies 10. The rear end of the insulating sleeve 1 is formed with an external thread 11, and a circular hoop 2 is screwed onto the external thread 11; the front end of each sleeve assembly 10 is also integrally formed with an end panel 13, the front surface of the end panel 13 is perpendicular to the central axis of the insulating sleeve 1, and the end panel is provided with a lock hole 130; the static contact 33, the intermediate contact body 320, and the grounding contact body 310 are tightly sleeved in the insulating sleeve 1.
[0038] Figure 4 , Figure 5 , Figure 6 , Figure 7 , Fig.12As shown, each semicircular sleeve assembly 10 is respectively provided with a first square notch 51, a second square notch 52, a first semicircular notch 53, and a second semicircular notch 54; when the two semicircular sleeve assemblies 10 are assembled, the two first square notches 51 are assembled to form a first observation window 61, the two second square notches 52 are assembled to form a second observation window 62, the two first semicircular notches 53 are assembled to form a first circular hollow hole 63, and the two second semicircular notches 54 are assembled to form a second circular hollow hole 64. The diameter of the first circular hollow hole 63 is the same as that of the intermediate contact boss 3. 21, the diameter of the second circular hollow hole 64 is the same as the diameter of the grounding contact boss 311, the middle contact boss 321 passes downward through the first circular hollow hole 63 and is exposed outside the insulating sleeve 1, and the grounding contact boss 311 passes upward through the second circular hollow hole 64 and is exposed outside the insulating sleeve 1; the rear end face of the connecting static contact 33 is exposed at the rear end of the insulating sleeve 1; the longitudinal position of the first observation window 61 is located between the connecting static contact 33 and the middle static contact 32, and the longitudinal position of the second observation window 62 is located between the middle static contact 32 and the grounding static contact 31.
[0039] Fig.13 , Fig.12 As shown, the outer surface of the moving contact 30 is provided with a slot 301 extending in the longitudinal direction, the middle static contact 32 is provided with screw holes 322 arranged symmetrically on the left and right, and each sleeve assembly 10 is provided with a mounting hole 12 at a position corresponding to the screw hole 322; a fastening screw 7 is also provided, and the fastening screw 7 includes a nut 71, a threaded section 72, and a smooth section 73 connected together in sequence, the surface of the threaded section 72 is provided with threads, and the surface of the smooth section 73 is not provided with threads, and the diameter of the smooth section 73 is smaller than the diameter of the threaded section 72, as shown in FIG. Fig. 9 , Fig.10 As shown; the fastening screw 7 passes through the mounting hole 12 of the insulating sleeve 1, the nut 71 of the fastening screw is pressed on the insulating sleeve 1, the threaded section 72 of the fastening screw is screwed into the screw hole 322 of the intermediate static contact 32, and the smooth section 73 of the fastening screw is embedded in the groove 301 on the outer surface of the moving contact, as shown Fig. 9 , Fig.10 shown.
[0040] Figure 4 , Fig.11 , Fig.12 As shown, the outer surface of the insulating sleeve 1 is formed with corrugated heat dissipation ribs 14, which is conducive to the heat dissipation of the three-position switch. The inner surface of the insulating sleeve 1 is formed with an annular convex rib 15 for limiting the longitudinal position of the static contact, which can limit the longitudinal position of each static contact in the longitudinal direction.
[0041] The installation method of the direct-acting three-position switch of the above embodiment is as follows: first, the grounding static contact 31, the intermediate static contact 32, and the closing static contact 33 are fixed and constrained in the insulating sleeve 1 to form a whole, the annular hoop 2 is tightened on the rear end of the insulating sleeve, and the fastening screw 7 is inserted into the mounting hole 12 of the insulating sleeve 1 and screwed into the screw hole 322 of the intermediate contact boss 321 to form an assembly of the direct-acting three-position switch; then, the entire assembly of the direct-acting three-position switch is placed in the air box 4, as shown in FIG. Fig.14 As shown, the front end of the insulating sleeve 1 is locked with the front wall 41 of the gas box by means of a bolt passing through the lock hole 130 of the end panel, so that the front end position of the two semicircular sleeve assemblies 10 is stable, thereby achieving the front end assembly and stability of the two semicircular sleeve assemblies 10; and the middle contact convex column 321 is connected to the through-wall conductive column, the through-wall conductive column passes through the bottom wall 43 of the gas box and enters the circuit breaker chamber, the lower end of the through-wall conductive column is connected to the circuit breaker busbar 35, the through-wall conductive column is wrapped with a through-wall sleeve seat 38, and the middle static contact 32 is supported on the bottom wall 43 of the gas box by means of the through-wall sleeve seat 38; and the branch busbar 36 inside the gas box can be directly connected to the rear end face of the static contact 33, and no insulating bracket is required between the static contact 33 and the rear wall 42 of the gas box. In addition, the static contact 33 does not need to be formed as a convex plate in one piece, and the static contact 33 can be a standard circular ring for easy processing. A camera for observing the position of the moving contact is arranged inside the air box 4 , and the camera is aimed at the first observation window 61 and the second observation window 62 .
Claims
1. A direct-acting three-position switch, comprising three fixed static contacts and one moving contact, wherein the three static contacts are, from front to back, a grounding static contact, an intermediate static contact, and a connection static contact, wherein the grounding static contact comprises a grounding contact body and a grounding contact boss protruding upward, and the intermediate static contact comprises an intermediate contact body and an intermediate contact boss protruding downward, wherein the cross sections of the grounding contact boss and the intermediate contact boss are both circular; the connection static contact, the intermediate contact body, and the grounding contact body are cylindrical, and the moving contact is a round rod, and the moving contact is driven by a screw mechanism to move between the inner cavities of the grounding contact body, the intermediate contact body, and the connection static contact; Features: An insulating sleeve is also provided, which is composed of two semicircular sleeve assemblies that are symmetrical on both sides; the said static contact, the middle contact body and the grounding contact body are tightly sleeved in the insulating sleeve; the rear end of the insulating sleeve is formed with an external thread, and a circular hoop is screwed with the external thread; the front end of each sleeve assembly is also integrally formed with an end panel, the front surface of the end panel is perpendicular to the central axis of the insulating sleeve, and the end panel is provided with a lock hole; Each semicircular sleeve assembly is respectively provided with a first square notch, a second square notch, a first semicircular notch, and a second semicircular notch; when the two semicircular sleeve assemblies are assembled, the two first square notches are assembled to form a first observation window, the two second square notches are assembled to form a second observation window, the two first semicircular notches are assembled to form a first circular hollow hole, and the two second semicircular notches are assembled to form a second circular hollow hole, the diameter of the first circular hollow hole is the same as the diameter of the middle contact boss, the diameter of the second circular hollow hole is the same as the diameter of the grounding contact boss, the middle contact boss passes through the first circular hollow hole and is exposed outside the insulating sleeve, and the grounding contact boss passes through the second circular hollow hole and is exposed outside the insulating sleeve; the rear end face of the connecting static contact is exposed at the rear end of the insulating sleeve; the longitudinal position of the first observation window is located between the connecting static contact and the middle static contact, and the longitudinal position of the second observation window is located between the middle static contact and the grounding static contact.
2. The direct-acting three-position switch according to claim 1, characterized in that: The outer surface of the moving contact is provided with a slot extending in the longitudinal direction; the middle stationary contact is provided with screw holes arranged symmetrically on the left and right, and each sleeve assembly is provided with a mounting hole at a position corresponding to the screw hole; a fastening screw is also provided, and the fastening screw includes a nut, a threaded section, and a smooth section which are connected as one body in sequence, the surface of the threaded section is provided with threads, the surface of the smooth section is not provided with threads, and the diameter of the smooth section is smaller than the diameter of the threaded section; the fastening screw passes through the mounting hole of the insulating sleeve, the nut of the fastening screw is pressed on the insulating sleeve, the threaded section of the fastening screw is screwed into the screw hole of the middle stationary contact, and the smooth section of the fastening screw is embedded in the slot on the outer surface of the moving contact.
3. The direct-acting three-position switch according to claim 1 or 2, characterized in that: The outer surface of the insulating sleeve is formed with corrugated heat dissipation ribs.
4. The direct-acting three-position switch according to claim 1 or 2, characterized in that: An annular convex rib for limiting the longitudinal position of the stationary contact is formed on the inner surface of the insulating sleeve.
5. The direct-acting three-position switch according to claim 1 or 2, characterized in that: The insulating sleeve is made of epoxy resin material.