A circuit breaker with a three-in-one composite spring structure

Abstract

The present invention discloses a circuit breaker with a three-in-one composite spring structure, wherein a mechanical linkage for opening and closing the switch and a moving contact bracket are coaxially arranged through a common axis in the circuit breaker housing, and a three-in-one composite spring structure is arranged between the mechanical linkage for opening and closing the switch and the moving contact bracket, and the three-in-one composite spring structure comprises a first force arm, a first torsion spring, a second force arm, a second torsion spring, a third force arm, a third torsion spring and a fourth force arm connected in sequence; the first torsion spring is installed on a rotating sleeve of the moving contact bracket with the common axis as the center of a circle, the first force arm extends out of the moving contact bracket and is pressed at point P on the circuit breaker housing, the second force arm extends out of the moving contact bracket and is pressed together with the mechanical linkage, the contact point is point Q, and the fourth force arm contacts the moving contact bracket at point R. The present invention utilizes a three-in-one composite spring structure to have both mechanical opening and closing and contact pressure holding functions, has a simple structure, is easy to manufacture, and creates favorable conditions for the simple structure and efficient production of the circuit breaker.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical switches, and in particular to a circuit breaker with a three-in-one composite spring structure. Background Art

[0002] A circuit breaker is an electrical protection component that can quickly cut off the power supply when an abnormality occurs. Ordinary current-limiting circuit breakers have a mechanical opening and closing mechanism and a contact pressure holding mechanism, and the entire mechanism is usually equipped with more than two springs. Due to their different functions, the two springs are generally called opening and closing mechanism springs and contact pressure springs. However, such a spring structure design is no longer suitable for the development requirements of modern industry, because the two spring components require two spring making machines to produce, and after different heat treatment processes, two sets of processing lines are required to assemble the two components, which creates difficulties for unmanned automatic assembly production lines and has high production costs. Therefore, strengthening the research and development and improvement of spring components inside circuit breakers has become an important research topic for technicians in the field of circuit breakers. Summary of the invention

[0003] The purpose of the present invention is to provide a circuit breaker with a three-in-one composite spring structure. A three-in-one composite spring structure is designed, which has both mechanical opening and closing functions and contact pressure holding functions. It has a simple structure and is easy to manufacture, creating favorable conditions for the simple structure and efficient production of small circuit breakers.

[0004] To achieve the above object, the present invention provides the following solutions:

[0005] A circuit breaker with a three-in-one composite spring structure, comprising a circuit breaker housing and a switch opening and closing mechanical linkage and a moving contact bracket arranged in the circuit breaker housing, wherein the switch opening and closing mechanical linkage and the moving contact bracket are coaxially arranged through a common axis, a three-in-one composite spring structure is arranged between the switch opening and closing mechanical linkage and the moving contact bracket, the three-in-one composite spring structure comprises a first torsion spring, a second torsion spring and a third torsion spring connected in sequence, one end of the first torsion spring is a first force arm, and the other end is connected to the second torsion spring through the second force arm, the second torsion spring is connected to one end of the third torsion spring through the third force arm, and the other end of the third torsion spring is a fourth force arm;

[0006] The first torsion spring is installed on the rotating sleeve of the moving contact bracket with the common axis as the center of the circle. The first force arm extends out of the moving contact bracket and is pressed against point P on the circuit breaker housing. The second force arm extends out of the moving contact bracket and is pressed together with the opening and closing mechanical linkage. The contact point is point Q. The two centers of the second torsion spring and the third torsion spring are floating and change their positions as the circuit breaker opening and closing mechanism rotates around the common axis. The fourth force arm contacts the moving contact bracket at point R. The torque between point P and point Q hinders the clockwise rotational displacement of the circuit breaker opening and closing mechanism around the common axis. The torque between point Q and point R is the combined torque generated by the floating second torsion spring and the third torsion spring, which hinders point R on the moving contact bracket and point Q on the opening and closing mechanical linkage from approaching each other for angular displacement.

[0007] Furthermore, the three-in-one composite spring structure is composed of three torsion springs connected in sequence wound from a steel wire.

[0008] Furthermore, the first force arm is pressed to the bottom of the circuit breaker housing along the inclined surface.

[0009] According to the specific embodiment provided by the present invention, the present invention discloses the following technical effects: the circuit breaker with a three-in-one composite spring structure provided by the present invention, a three-in-one composite spring structure is arranged between the opening and closing mechanical linkage and the moving contact bracket, and has the following technical advantages:

[0010] First, three torsion springs are wound simultaneously using one steel wire, which improves the efficiency of the spring manufacturing process. The opening and closing force of the circuit breaker, the frequency of mechanical life, and the holding force of the contact pressure are completely achieved through the design of the diameter size, force arm length, force arm angle, and steel wire diameter of the three springs. The structure is simple and the manufacturing is convenient.

[0011] Second, it is only necessary to determine the installation positions of the first torsion spring, the first force arm, the second force arm and the fourth force arm. The entire composite spring can be easily installed through multi-point positioning, thereby improving the efficiency of circuit breaker assembly and facilitating production line management. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0013] Figure 1 It is a structural schematic diagram of a circuit breaker with a three-in-one composite spring structure according to the present invention;

[0014] Figure 2It is a structural schematic diagram of the three-in-one composite spring structure of the present invention;

[0015] Figure 3 It is a perspective view of the assembly of the three-in-one composite spring structure of the present invention in a circuit breaker;

[0016] Figure 4 A schematic diagram of the working state of the circuit breaker of the three-in-one composite spring structure of the present invention;

[0017] Reference numerals: 1. static contact; 2. moving contact; 3. moving contact bracket; 4. three-in-one composite spring structure; 5. opening and closing mechanical linkage; 6. handle; 7. U-shaped connecting rod; 8. shift block; 9. trip lever; 10. circuit breaker housing; 11. common shaft;

[0018] 4-1, first force arm; 4-2, first torsion spring; 4-3, second force arm; 4-4, second torsion spring; 4-5, third force arm; 4-6, third torsion spring; 4-7, fourth force arm. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] The purpose of the present invention is to provide a circuit breaker with a three-in-one composite spring structure. A three-in-one composite spring structure is designed, which has both mechanical opening and closing functions and contact pressure holding functions. It has a simple structure and is easy to manufacture, creating favorable conditions for the simple structure and efficient production of small circuit breakers.

[0021] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] like Figures 1 to 4 As shown, a circuit breaker with a three-in-one composite spring structure provided by the present invention comprises a circuit breaker housing 10 and a switch opening and closing mechanical linkage 5 and a moving contact bracket 3 arranged in the circuit breaker housing 10, wherein the switch opening and closing mechanical linkage 5 and the moving contact bracket 3 are coaxially arranged through a common shaft 11, and the circuit breaker housing 10 is further provided with common structures such as a static contact 1, a moving contact 2, a handle 6, a U-shaped connecting rod 7, a shifting block 8 and a tripping lever 9, wherein the switch opening and closing mechanical linkage 5, the shifting block 8 and the tripping lever 9 are regarded as a whole when there is no tripping action (known in the industry), and the moving contact 2 and the moving contact bracket 3 are a co-cast assembly;

[0023] A three-in-one composite spring structure 4 is provided between the opening and closing mechanical linkage 5 and the moving contact bracket 3, and the three-in-one composite spring structure 4 includes a first torsion spring 4-2, a second torsion spring 4-4 ​​and a third torsion spring 4-6 connected in sequence, one end of the first torsion spring 4-2 is a first force arm 4-1, and the other end is connected to the second torsion spring 4-4 ​​through a second force arm 4-3, the second torsion spring 4-4 ​​is connected to one end of the third torsion spring 4-6 through a third force arm 4-5, and the other end of the third torsion spring 4-6 is a fourth force arm 4-7;

[0024] The first torsion spring 4-2 is installed on the rotating sleeve of the moving contact bracket 3 with the common axis as the center of the circle. The first force arm 4-1 extends out of the moving contact bracket 3 and is pushed at point P on the circuit breaker housing 10. The second force arm 4-3 extends out of the moving contact bracket 3 and is pushed together with the opening and closing mechanical linkage 5. The contact point is point Q. The two centers of the second torsion spring 4-4 ​​and the third torsion spring 4-6 are floating and change positions as the circuit breaker opening and closing mechanism rotates around the common axis. The fourth force arm 4-7 contacts the moving contact bracket 3 at point R. The torque between point P and point Q hinders the clockwise rotational displacement of the circuit breaker opening and closing mechanism around the common axis 11. The torque between point Q and point R is the combined torque generated by the floating second torsion spring 4-4 ​​and the third torsion spring 4-6, which hinders point R on the moving contact bracket 3 and point Q on the opening and closing mechanical linkage 5 from approaching each other for angular displacement.

[0025] The three-in-one composite spring structure 4 is composed of three torsion springs connected in sequence wound from a steel wire. The first force arm 4-1 is pressed to the bottom of the circuit breaker housing 10 along the inclined surface. Below the inclined surface is a vertical rib of the circuit breaker housing, which is also the fulcrum of the force arm when the first force arm 4-1 is installed in the housing. The function of the inclined surface is to ensure that when the first force arm is pressed into the vertical rib fulcrum of the housing, it slides along the inclined surface, so that the first force arm 4-1 automatically generates a pre-torque, which is the known initial torque of the circuit breaker handle. Due to the action of the inclined surface, the opening and closing mechanism has the initial torque of the static contact 1 and the moving contact 2 in the disconnected state.

[0026] The length of the first force arm 4-1 is approximately the distance from the center of the first torsion spring 4-2 to point P. The torque between point P and point Q on the first force arm 4-1 and the second force arm 4-3 of the first torsion spring 4-2 hinders the clockwise rotational displacement of the circuit breaker opening and closing mechanism around the common axis 11, or in other words, this torque hinders the moving contact 2 from rotating in the direction of contacting the static contact 1. The second torsion spring 4-4 ​​and the third torsion spring 4-6 continuously change their positions as the circuit breaker opening and closing mechanism rotates around the common axis 11, and the length of the fourth force arm 4-7 is the distance from the center of the third torsion spring 4-6 to point R.

[0027] The torque between the Q point and the R point is the combined torque generated by the two floating second torsion springs 4-4 and the third torsion spring 4-6, which hinders the R point on the moving contact bracket 3 and the Q point on the opening and closing mechanical linkage 5 from approaching each other in angular displacement; since the closing push action of the handle 6 generates a closing torque, the closing torque is transmitted to the opening and closing mechanical linkage 5 through the U-shaped connecting rod 7, the shift block 8, and the tripping lever 9. The closing torque is an active torque. In the three-in-one composite spring structure 4, the hindering torque between the P point and the Q point is the reaction torque; the opening and closing mechanical linkage 5 transmits the received closing torque to the second torsion spring 4-4 ​​and the third torsion spring 4-6 through its own Q point. The third torsion spring 4-6 pushes the moving contact bracket 3 to make a clockwise closing rotation at the R point. When the moving contact 2 touches the static contact 1, the moving contact 2 and the moving contact bracket 3 cast therewith enter a stationary state. However, at this time, the opening and closing mechanical linkage 5 continues to rotate under the closing torque of the handle 6. The rotation causes the second torsion spring 4-4 ​​and the third torsion spring 4-6 to twist and deform, and the combined torque is generated between the Q point and the R point. The combined torque is an active torque, which generates a contact contact pressure between the static contact 1 and the moving contact 2. The torque obtained by multiplying the contact pressure by the distance between the contact point and the common axis 11 is the reaction torque of the combined torque.

[0028] The conduction and disconnection of the circuit breaker, or the contact and separation of the static contact 1 and the moving contact 2, are all driven by a set of tripping mechanisms through the U-shaped connecting rod 7 on the circuit breaker handle 6. The tripping mechanism is installed on the opening and closing mechanical linkage 5. Therefore, the closing torque is transmitted from the handle 6 to the opening and closing mechanical linkage 5. The opening and closing mechanical linkage 5 then transmits this closing torque to the second force arm 4-3, causing it to rotate clockwise. At this time, the first force arm 4-1 is stationary on the circuit breaker housing 10, so a resisting torque is generated between the two force arms of the first torsion spring 4-2. When the handle force is released, or the circuit breaker is protectively tripped, the resisting torque will immediately cause the moving contact 2 to be out of contact with the static contact 1. The above situation will not occur under normal circumstances. The torsion angle between the first force arm 4-1 and the second force arm 4-3 will continue to increase as the handle 6 has not completed the closing action. For conventional circuit breaker design, even if the static contact 1 and the moving contact 2 have begun to contact, the moving contact bracket 3 co-cast with the moving contact 2 has also entered a static state, that is, point R thereon is stationary. As the torsion angle between the first force arm 4-1 and the second force arm 4-3 continues to increase, point Q gets closer and closer to point R, indicating that the second torsion spring 4-4 ​​and the third torsion spring 4-6 have been twisted and deformed, and a compressive torque has been generated between point Q and point R, which is the "combined torque". This combined torque is very important because it determines the contact pressure between the static contact 1 and the moving contact 2, contact overtravel and other important switching parameters.

[0029] The circuit breaker with a three-in-one composite spring structure provided by the present invention uses one steel wire to simultaneously wind three torsion springs, thereby improving the efficiency of the spring manufacturing process. The opening and closing force of the circuit breaker, the frequency of the mechanical life, and the maintaining force of the contact pressure are completely achieved by designing the diameters of the three springs, the lengths of the force arms, the angles of the force arms, and the diameters of the steel wires. The structure is simple and the manufacturing is convenient. It only needs to determine the installation positions of the first torsion spring, the first force arm, the second force arm, and the fourth force arm. The entire composite spring can be easily installed through multi-point positioning, thereby improving the assembly work efficiency of the circuit breaker, facilitating the management of the production line, and creating favorable conditions for the simple structure and efficient production of small circuit breakers.

[0030] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A circuit breaker with a three-in-one composite spring structure, comprising a circuit breaker housing (10) and a switch opening and closing mechanical linkage member (5) and a moving contact bracket (3) arranged in the circuit breaker housing (10), wherein the switch opening and closing mechanical linkage member (5) and the moving contact bracket (3) are coaxially arranged via a common shaft (11), It is characterized in that A three-in-one composite spring structure (4) is provided between the opening and closing mechanical linkage (5) and the moving contact bracket (3), the three-in-one composite spring structure (4) comprising a first torsion spring (4-2), a second torsion spring (4-4) and a third torsion spring (4-6) connected in sequence, one end of the first torsion spring (4-2) being a first force arm (4-1), and the other end being connected to the second torsion spring (4-4) via a second force arm (4-3), the second torsion spring (4-4) being connected to one end of the third torsion spring (4-6) via a third force arm (4-5), and the other end of the third torsion spring (4-6) being a fourth force arm (4-7); The first torsion spring (4-2) is mounted on a rotating shaft sleeve of the moving contact bracket (3) with the common axis as the center of the circle. The first force arm (4-1) extends out of the moving contact bracket (3) and is pressed against point P on the circuit breaker housing (10). The second force arm (4-3) extends out of the moving contact bracket (3) and is pressed together with the opening and closing mechanical linkage (5), with the contact point being point Q. The centers of the two circles of the second torsion spring (4-4) and the third torsion spring (4-6) are floating. As the circuit breaker opens and closes, the first force arm (4-1) extends out of the moving contact bracket (3) and is pressed against point P on the circuit breaker housing (10). The structure changes position by rotating around the common axis, the fourth force arm (4-7) contacts the moving contact bracket (3) at point R, the torque between point P and point Q hinders the clockwise rotation displacement of the circuit breaker opening and closing mechanism around the common axis (11), and the torque between point Q and point R is the combined torque generated by the floating second torsion spring (4-4) and the third torsion spring (4-6), which hinders the angular displacement of point R on the moving contact bracket (3) and point Q on the opening and closing mechanical linkage (5) from approaching each other.

2. The circuit breaker with a three-in-one composite spring structure according to claim 1, It is characterized in that The three-in-one composite spring structure (4) is composed of three torsion springs connected in sequence wound from a steel wire.

3. The circuit breaker with a three-in-one composite spring structure according to claim 1, It is characterized in that The first force arm (4-1) is pressed to the bottom of the circuit breaker housing (10) along the inclined surface.

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