Self-operated double-layer contact and removable conductive arm assembly
By adopting a self-forced double-layer contact design in the circuit breaker, the optimized layout of the inner and outer contact fingers achieves double-layer flow diversion, which solves the heating problem caused by excessive current density of the contact and improves the stability and safety of the equipment.
Patent Information
- Application Number
- CN202411716127.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-27
- Publication Date
- 2025-03-25
AI Technical Summary
When existing contacts are too large to load or sudden current, they are prone to heat up due to the large current density of single-electric contacts and the tunneling effect of electrical contacts, resulting in an increase in temperature and may cause equipment failure or safety accidents.
The self-reliable double-layer contact design is adopted, in which the outer contact and the inner contact are electrically connected to the conductive base, and the conductive area and length of the inner and outer contact fingers are optimized respectively to achieve double-layer flow diversion in the inner and outer contact fingers and reduce the current density of a single contact finger.
Through the internal and external double-layer flow diversion design, the conductivity and current carrying capacity are improved, local overheating and current concentration are reduced, and the operating stability and safety of the circuit breaker are improved.
Smart Images
Figure CN119694816A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the field of circuit breakers, and in particular to a self-powered double-layer contact and a removable conductive arm assembly. Background Art
[0002] At present, when the contact commonly used in industry is inserted into the static contact, each contact point on the contact point contacts the contact point of the static contact to form an electrical connection. At the same time of contact, the spring device provides a stable contact force to ensure the stability and reliability of the electrical connection. Even when the external environment changes (such as temperature, humidity, etc.), a stable electrical connection can be maintained. However, when the load is too large or the current changes suddenly, the contact may generate heat due to the large current density of a single electrical contact and the tunnel effect of the electrical contact, which cannot withstand excessive current. In addition, the contact temperature will rise in the state of long-term heating, which may cause equipment failure or safety accidents when it exceeds the specified value. In addition, high temperature will also aggravate the ablation and oxidation of the contact, further increasing the contact resistance and heat generation. Summary of the invention
[0003] The technical problem to be solved by the present invention is to provide a self-supporting double-layer contact and a removable conductive arm assembly to achieve shunting and heat reduction when the contact is working.
[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is: A self-powered double-layer contact, comprising an outer contact, an inner contact and a conductive base; The outer contact and the inner contact are electrically connected to the conductive base respectively; the outer contact includes a plurality of outer contact fingers arranged in a ring array, the inner contact includes a plurality of inner contact fingers arranged in a ring array, and the inner contact is concentrically arranged inside the outer contact; the conductive area of the inner contact finger is larger than that of the outer contact finger.
[0005] In order to solve the above technical problems, another technical solution adopted by the present invention is: A removable conductive arm assembly comprises the self-powered double-layer contact and a tubular static contact, wherein the tubular static contact is meshedly connected with the self-powered double-layer contact, and the tubular static contact is electrically connected with the outer contact finger and the inner contact finger respectively.
[0006] The beneficial effects of the present invention are: providing a self-powered double-layer contact and a removable conductive arm assembly, by setting inner and outer double-layer contacts and electrically connecting both to the conductive base, so that when the double-layer contact is engaged with the tubular static contact, the inner and outer double-layer current conduction is realized, and the number of electrical contacts is increased by more than 50%, which not only improves the conductive efficiency, but also enhances the current carrying capacity; in addition, due to the skin effect of the tubular (rod) static contact in the AC system, the conductive area of the inner contact finger is larger than that of the outer contact finger, and the length is shorter than that of the outer contact finger (which is essentially the same as the arcing contact finger). The difference is that when working in the normal closing position, the inner arcing contact fingers basically do not participate in the current conduction. When opening, the inner arcing contact fingers start to conduct the current, so that the current conduction resistance of a single inner contact finger is lower than the current conduction resistance of a single outer contact finger, and the current between the inner and outer contact fingers is re-matched, the current density of the outer contact fingers is reduced, the influence of the skin effect is solved, and the current density of the inner contact fingers is increased, thereby greatly reducing the current density of a single contact finger by more than 33%, and reducing the heat generated by a single electrical contact by more than 50%, solving the problems of current concentration and local overheating, and improving the operation stability of the circuit breaker. BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Figure 1 It is a schematic diagram of the assembly of a self-supporting double-layer contact in an embodiment of the present invention; Figure 2 A top view of a self-supporting double-layer contact in an embodiment of the present invention; Figure 3 is a schematic diagram of a threaded connection type outer contact in an embodiment of the present invention; Figure 4 is a schematic diagram of a threaded connection type inner contact in an embodiment of the present invention; Figure 5 is a schematic diagram of a bolt-connected outer contact in an embodiment of the present invention; Figure 6 is a schematic diagram of a bolt-connected inner contact in an embodiment of the present invention; Figure 7 It is a schematic diagram of the assembly of a self-supporting double-layer contact and a static contact in an embodiment of the present invention; Figure 8 It is an axial cross-sectional view of a self-powered double-layer contact and a stationary contact after being assembled in an embodiment of the present invention; Description of labels: 1. Outer contact; 11. Outer contact finger; 2. Inner contact; 21. Inner contact finger; 22. Connecting part; 23. Bolt hole; 3. Conductive base; 4. Static contact. DETAILED DESCRIPTION
[0008] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following is an explanation in combination with the implementation modes and the accompanying drawings.
[0009] Please refer to Figures 1 to 8, a self-supporting double-layer contact, comprising an outer contact 1, an inner contact 2 and a conductive base 3; The outer contact 1 and the inner contact 2 are electrically connected to the conductive base 3 respectively; the outer contact 1 includes a plurality of outer contact fingers 11 arranged in a ring array, the inner contact 2 includes a plurality of inner contact fingers 21 arranged in a ring array, and the inner contact 2 is concentrically arranged inside the outer contact 1; the conductive area of the inner contact finger 21 is larger than that of the outer contact finger 11.
[0010] A removable conductive arm assembly includes the self-powered double-layer contact and a tubular static contact 4, wherein the tubular static contact 4 is meshedly connected with the self-powered double-layer contact, and the tubular static contact 4 is electrically connected with the outer contact finger 11 and the inner contact finger 21 respectively.
[0011] It is understandable that the skin effect will occur in the process of conducting electricity in tubular conductors. The skin effect refers to the fact that when alternating current flows in a conductor, it tends to flow to the surface of the conductor due to the effect of the electromagnetic field, and the current is mainly concentrated on the outer layer of the conductor. For tubular conductors (i.e. hollow tubular conductors), the skin effect is more obvious because this type of conductor itself has no solid internal conductive material, and the current will be further concentrated on the outer layer of the conductor. In order to solve the current conduction influence caused by the skin effect of the tubular conductor, the present invention sets inner and outer double-layer contacts and electrically connects them to the conductive base 3, so that the double-layer contacts can realize inner and outer double-layer current conduction when they are engaged with the tubular static contact 4, which not only improves the conductive efficiency but also enhances the current carrying capacity; in addition, due to the skin effect of the tubular static contact 4, the conductive area of the inner contact finger 21 is set to be larger than the outer contact finger 11, so that the current conduction resistance of a single inner contact finger 21 is lower than the current conduction resistance of a single outer contact finger 11, and the current between the inner and outer contact fingers 11 is re-matched to solve the influence of the skin effect on the current density of the inner contact finger 21, thereby reducing the phenomenon of local overheating and current concentration, and improving the operating stability of the circuit breaker.
[0012] The removable conductive arm is a common conductive component in high-voltage electrical equipment (such as circuit breakers, disconnectors, etc.), which is mainly used to realize the detachable connection of the equipment in the electrical circuit. It usually uses a mechanical structure to enable it to be separated or contacted with the corresponding contact component when needed to achieve the circuit conduction or disconnection function. When the conductive arm contacts other parts of the equipment (such as the static contact 4 and the plum blossom contact), an electrical circuit is formed to ensure efficient transmission of current. Originally, the conductive arm and the plum blossom contact adopted a separate structural design, but this design limits the effective utilization rate of the conduction cross section to a certain extent. In order to further improve the conduction performance and structural integrity of the circuit breaker, the present invention combines the contact arm and the plum blossom contact into an integrated structure.
[0013] Specifically, the outer contact 1 and the inner contact 2 both include M-type self-reliant plum blossom contact fingers. By designing that both the inner and outer contacts 1 include M-type self-reliant plum blossom contact fingers, each contact finger is evenly distributed and the contact area is increased, thereby generating a more uniform current distribution when current passes through, further reducing the influence of the skin effect. This plum blossom structure increases the contact surface of the contact, reduces the contact resistance, and makes the current more evenly distributed between the contact points, thereby reducing local overheating and improving the conductive stability and wear resistance of the contact.
[0014] In the embodiment of the present invention, the outer contact 1 is integrated with the conductive base 3 , and the inner contact 2 is assembled and connected with the conductive base 3 .
[0015] From the above description, it can be seen that the outer contact 1 and the conductive base 3 are designed as an integrated whole, and the inner contact 2 is connected to the conductive base 3 by assembly. This configuration optimizes the manufacturing process, so that the outer contact 1 has better stability and reduces the additional connection resistance. At the same time, it ensures that the inner contact 2 has convenient disassembly and assembly characteristics, making the installation and maintenance of the contact more flexible. The replacement or repair of the inner contact 2 can be quickly adjusted according to specific usage requirements, thereby ensuring the long-term reliability and ease of operation of the equipment.
[0016] In the embodiment of the present invention, the length of the inner contact finger 21 is smaller than the length of the outer contact finger 11 .
[0017] From the above description, it can be seen that the length of the inner contact finger 21 is shorter than that of the outer contact finger 11, which effectively reduces the loop resistance of the inner contact finger 21, making the conductive path of the inner contact finger 21 shorter and easier for current to pass through. This not only increases the current conduction capacity of the inner contact finger 21, and compensates for the phenomenon that the current tends to the outer contact finger 11 due to the skin effect, but also further balances the current distribution between the inner and outer contact fingers, making the conductive performance of the double-layer contact more uniform, effectively reducing the temperature rise of the circuit breaker when working under high load, and improving the safety and reliability of the equipment.
[0018] In an embodiment of the present invention, the width of the inner contact finger 21 is greater than the width of the outer contact finger 11 .
[0019] From the above description, it can be seen that by designing the width of the inner contact finger 21 to be greater than the width of the outer contact finger 11, the inner contact finger 21 has a larger conductive cross-sectional area, thereby reducing its current conduction resistance and improving the conductivity of the inner contact finger 21. The current distribution between the inner and outer contact fingers 11 is effectively improved, the influence of the skin effect on the current conduction of the inner contact finger 21 is reduced, and the current between the inner and outer contact fingers is evenly distributed, which reduces the local heating phenomenon of the equipment, thereby improving the stability and conductive efficiency of the circuit breaker under high load.
[0020] In the embodiment of the present invention, the inner contact 2 further comprises a connecting portion 22 , the inner contact finger 21 is disposed on the connecting portion 22 , and the connecting portion 22 is threadedly connected to the conductive base 3 .
[0021] As can be seen from the above description, by providing the connection portion 22, the inner contact finger 21 can be connected to the conductive base 3 through a thread, thereby increasing the mechanical stability and electrical reliability between the contact finger and the conductive base 3. This structure makes the connection of the inner contact 2 more stable, reducing the increase in resistance and current instability caused by looseness or poor contact. At the same time, the threaded connection is easy to disassemble and maintain, and can be quickly replaced or repaired when the contact is worn or other faults occur, thereby improving the maintenance efficiency and service life of the equipment.
[0022] In the embodiment of the present invention, the contact recess of the outer contact finger 11 is arranged opposite to the contact recess of the inner contact finger 21 .
[0023] As can be seen from the above description, by arranging the contact recesses of the outer contact finger 11 and the inner contact finger 21 relatively, the two contact fingers can form a stable multi-point contact when in contact, thereby increasing the stability of the contact surface and the uniformity of the contact pressure. This design improves the contact quality of the contact, reduces the contact resistance, makes the current conduction smoother, and reduces the local overheating phenomenon that may be generated when the current flows through a single point, thereby improving the conductive performance of the contact and the safety of the equipment.
[0024] In an embodiment of the present invention, fixed contact rings are provided on two opposite surfaces of the outer contact finger 11 and the inner contact finger 21 .
[0025] From the above description, it can be known that, in the above-mentioned contact fixed contact ring, when the circuit breaker is slowly shaken in to the position where the static contact 4 just contacts, a mark will be left on the fixed contact ring. After the circuit breaker is shaken out, the mark on the contact ring is observed. The shape and position of the mark can be used to determine whether the circuit breaker contact and the static contact 4 are coaxial. If the situation of misalignment is found, the position of the static contact 4 can be adjusted until it meets the operating requirements, thereby improving the accuracy of the above-mentioned contact alignment, avoiding local overcurrent overload, causing overheating, and further improving the operating stability. Preferably, a conductive paste is provided on the static contact 4, and the conductive paste makes it easier to capture the mark of the fixed contact ring. In an embodiment of the present invention, the ratio of the diameter of the annular array of the inner contact 2 to the diameter of the annular array of the outer contact 1 is in the range of 80-90%. By designing the diameter of the annular array of the inner contact 2 to be 80-90% of the diameter of the annular array of the outer contact 1, the arrangement of the inner contact 2 is optimized, so that the inner and outer contacts 1 produce a more uniform current distribution when current passes through. This design reduces the potential difference between the inner and outer contacts, reduces the phenomenon of current concentrated flow in the outer layer, thereby reducing the influence of the skin effect on the conductive path, and improving the overall conductive efficiency and current uniformity of the contact.
[0026] The present invention provides a self-supporting double-layer contact and a removable conductive arm assembly, which is mainly used to realize the shunting and heat reduction of a circuit breaker, and is specifically described below in conjunction with an embodiment.
[0027] Please refer to Figures 1 to 8 , Embodiment 1 of the present invention is: A self-powered double-layer contact comprises an outer contact 1, an inner contact 2 and a conductive base 3; the outer contact 1 and the inner contact 2 are electrically connected to the conductive base 3 respectively; the outer contact 1 comprises a plurality of outer contact fingers 11 arranged in a ring array, the inner contact 2 comprises a plurality of inner contact fingers 21 arranged in a ring array, and the inner contact 2 is concentrically arranged inside the outer contact 1; the conductive area of the inner contact finger 21 is larger than that of the outer contact finger 11. Specifically, the outer contact 1 and the inner contact 2 are both M-type self-powered plum blossom contact fingers, and the contact notch of the outer contact finger 11 is arranged opposite to the contact notch of the inner contact finger 21.
[0028] A removable conductive arm assembly includes a self-powered double-layer contact and a tubular static contact 4, wherein the tubular static contact 4 is meshedly connected with the self-powered double-layer contact, and the tubular static contact 4 is electrically connected with an outer contact finger 11 and an inner contact finger 21 respectively.
[0029] At the same time, the diameter of the annular array of the inner contact 2 is 90% of the diameter of the annular array of the outer contact 1. By designing the diameter of the annular array of the inner contact 2 to be 90% of the diameter of the annular array of the outer contact 1, the arrangement of the inner contact 2 is optimized, so that the inner and outer contacts 1 produce a more uniform current distribution when current passes through. This design reduces the potential difference between the inner and outer contacts, reduces the phenomenon of concentrated current flow in the outer layer, thereby reducing the impact of the skin effect on the conductive path, and improving the overall conductive efficiency and current uniformity of the contact.
[0030] That is, in this embodiment, in order to solve the skin effect of the tubular conductor and realize heat reduction and current diversion at the same time, inner and outer double-layer contacts are set and are electrically connected to the conductive base 3, so that when the double-layer contact is engaged with the tubular static contact 4, inner and outer double-layer current conduction is realized, which not only improves the conductive efficiency, but also enhances the current carrying capacity; in addition, the conductive area of the inner contact finger 21 is set to be larger than the outer contact finger 11, so that the current conduction resistance of a single inner contact finger 21 is lower than the current conduction resistance of a single outer contact finger 11, and the current between the inner and outer contact fingers 11 is re-matched, so as to solve the influence of the skin effect on the current density of the inner contact finger 21, thereby reducing the phenomenon of local overheating and current concentration, and improving the operating stability of the circuit breaker.
[0031] Embodiment 2 of the present invention is: On the basis of the first embodiment, the outer contact 1 is integrated with the conductive base 3 , and the inner contact 2 is assembled and connected with the conductive base 3 .
[0032] Specifically, the inner contact 2 also includes a connecting portion 22, and the inner contact finger 21 is arranged on the connecting portion 22, and the connecting portion 22 is threadedly connected to the conductive base 3. Alternatively, the connecting portion 22 and the conductive base 3 are locked by bolts, and the conductive base 3 and the connecting portion 22 are both provided with matching bolt holes 23. The inner contact finger 21 can be connected to the conductive base 3 by threads or bolts, thereby increasing the mechanical stability and electrical reliability between the contact finger and the conductive base 3. This structure makes the connection of the inner contact 2 more stable, reducing the increase in resistance and current instability caused by looseness or poor contact. At the same time, the threaded or bolted connection is easy to disassemble and maintain, and can be quickly replaced or repaired when the contact is worn or other faults occur, thereby improving the maintenance efficiency and service life of the equipment.
[0033] The length of the inner contact finger 21 is less than the length of the outer contact finger 11, and the width of the inner contact finger 21 is greater than the width of the outer contact finger 11. By designing the width of the inner contact finger 21 to be greater than the width of the outer contact finger 11, the inner contact finger 21 has a larger conductive cross-sectional area, and the length of the inner contact finger 21 is less than the length of the outer contact finger 11, which effectively reduces the loop resistance of the inner contact finger 21 and makes it easier for current to pass. Not only does it increase the current conduction capacity of the inner contact finger 21, and compensate for the phenomenon that the current tends to the outer contact finger 11 due to the skin effect, it also further balances the current distribution between the inner and outer contact fingers, making the conductive performance of the double-layer contact more uniform, effectively reducing the temperature rise of the circuit breaker when working under high load, and improving the safety and reliability of the equipment.
[0034] Embodiment 3 of the present invention is: On the basis of the first embodiment, fixed contact rings are provided on the opposite sides of the outer contact finger 11 and the inner contact finger 21. That is, on the above-mentioned contact fixed contact ring, when the circuit breaker is slowly shaken in to the position where the static contact 4 just contacts, a mark will be left on the fixed contact ring. After the circuit breaker is shaken out, the mark on the contact ring is observed. By observing the shape and position of the mark, it can be determined whether the circuit breaker contact and the static contact 4 are coaxial. If the situation of misalignment is found, the position of the static contact 4 can be adjusted until it meets the operating requirements, thereby improving the accuracy of the above-mentioned contact alignment, avoiding local overcurrent overload, resulting in overheating, and further improving the operating stability. Preferably, a conductive paste is provided on the static contact 4, and the conductive paste makes it easier to capture the mark of the fixed contact ring. In summary, the present invention provides a self-powered double-layer contact and a removable conductive arm assembly. The self-powered double-layer contact realizes inner and outer double-layer current diversion during the conduction process through the innovatively designed inner and outer double-layer contact structure, so that the current is effectively distributed between the inner contact fingers and the outer contact fingers, greatly improving the conduction efficiency and current carrying capacity. This double-layer current guide design not only effectively addresses the current density concentration problem caused by the skin effect of the tubular static contact, but also balances the uniform distribution of the current and reduces the phenomenon of local overheating, thereby significantly improving the stability and reliability of the circuit breaker operation. In addition, by setting the conductive area of the inner contact finger to be larger than the outer contact finger, the current conduction capacity of the inner contact finger is optimized, the current conduction resistance of the inner contact finger is reduced, and the current distribution between the inner and outer contact fingers is more uniform, thereby further reducing the temperature rise of the equipment under high load conditions; At the same time, the design of integrating the outer contact with the conductive base further increases the structural stability of the contact. The inner contact is connected to the conductive base through threads or bolts, which enhances the mechanical stability and electrical reliability of the contact and reduces the increase in resistance and current instability caused by looseness or poor contact. This structure facilitates the assembly and maintenance of the equipment. When the contact is worn or fails, it can be quickly replaced or repaired, which improves the maintenance efficiency and service life of the equipment.
[0035] In addition, a fixed contact ring is set on the contact finger, so that the contact position and contact condition can be observed more accurately during the debugging process. Through the mark on the fixed contact ring, technicians can determine whether the circuit breaker contact and the static contact are coaxial, and then make necessary adjustments to avoid local overcurrent and temperature abnormalities of the contact. In addition, conductive paste is applied to the static contact to make the mark of the fixed contact ring clearer, further improving the accuracy of the contact alignment, thereby ensuring the stability of the equipment in actual operation.
[0036] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention's specification and drawings, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.
Claims
1. A self-supporting double-layer contact, characterized in that: It includes an outer contact, an inner contact and a conductive base; The outer contact and the inner contact are electrically connected to the conductive base respectively; the outer contact includes a plurality of outer contact fingers arranged in a ring array, the inner contact includes a plurality of inner contact fingers arranged in a ring array, and the inner contact is concentrically arranged inside the outer contact; the conductive area of the inner contact finger is larger than that of the outer contact finger.
2. A self-supporting double-layer contact according to claim 1, characterized in that: The outer contact is integrated with the conductive base, and the inner contact is assembled and connected with the conductive base.
3. A self-supporting double-layer contact according to claim 2, characterized in that: The length of the inner contact finger is smaller than the length of the outer contact finger.
4. A self-supporting double-layer contact according to claim 2, characterized in that: The width of the inner contact finger is greater than the width of the outer contact finger.
5. A self-powered double-layer contact according to claim 2, characterized in that: The inner contact also includes a connecting portion, the inner contact finger is arranged on the connecting portion, and the connecting portion is threadedly connected to the conductive base.
6. A self-powered double-layer contact according to claim 1, characterized in that: The contact recess of the outer contact finger is arranged opposite to the contact recess of the inner contact finger.
7. A self-powered double-layer contact according to claim 6, characterized in that: Two opposite surfaces of the outer contact finger and the inner contact finger are provided with fixed contact rings.
8. The self-supporting double-layer contact according to claim 1, characterized in that: The ratio of the diameter of the annular array of the inner layer contacts to the diameter of the annular array of the outer layer contacts is in the range of 80-90%.
9. A self-supporting double-layer contact according to claim 1, characterized in that: The outer contact and the inner contact both include M-shaped self-supporting plum blossom contact fingers.
10. A removable conductive arm assembly, characterized in that: It comprises the self-powered double-layer contact and the tubular static contact as described in any one of claims 1 to 9, wherein the tubular static contact is meshedly connected with the self-powered double-layer contact, and the tubular static contact is electrically connected with the outer contact finger and the inner contact finger respectively.